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TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: mjydrafter on May 12, 2013, 10:57:59 AM
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(http://i216.photobucket.com/albums/cc295/mjydrafter/20130509_164406_zps9a4c09cc.jpg)
I kind of knew that my fan was junk. I could spin the blade by hand, but it was really stiff. Further inspection revealed that the fan blade was just spinning on the shaft and the shaft was not turning.
I had the fan and radiator that the PO had replaced prior to me getting the bike. So I inspected that as well, FUBAR'd just like the current one. This one had done the popular number of drilling into the back side of the radiator and ruining it. Stupid design.
(http://i216.photobucket.com/albums/cc295/mjydrafter/20130509_061116_zpsfae69de9.jpg)
Both fan motors besides being stuck fast, had the at least one of the brush holders completely melted, and not operable.
I did a bit of research and decided that replacing the crap fan with the same crap fan was silly. I found a few posts here and there about what could be used in place of the original fan.
What I found was that the Spal 6.5" puller fan was a good option. Just fab up a bracket, soldier the BMW fan connector on and we should be good to go.
(http://i216.photobucket.com/albums/cc295/mjydrafter/20130509_164601_zps1feeba8b.jpg)
(http://i216.photobucket.com/albums/cc295/mjydrafter/20130509_165759_zps33cf870c.jpg)
(http://i216.photobucket.com/albums/cc295/mjydrafter/20130510_112152_zps34b33b35.jpg)
I made up the bracket, and attached the fan to it. I covered the screwheads and back of my bracket with some cork gasket material, so nothing should rub.
I decided that the K100 Radiator, although I can't use the stock K75 radiator surround, is the better bigger radiator. The 75 radiator must be a 2 or 3 core vs. the 100's 4 core, it is thicker.
Most of the documentation I found said that you must remove the radiator to remove the fan. Now I must admit, that my bike being pretty naked is already pretty easy to get to the radiator. I removed the tank (more on that later), I removed the air box top, and the intake that goes up to side of the rad. Then I removed the top rad. bolt and took out the 2 bolts holding the radiator fill and hose. With those removed I could move the rad. off of the bottom mounts.
(http://i216.photobucket.com/albums/cc295/mjydrafter/20130510_110910_zps82d2bfa9.jpg)
(http://i216.photobucket.com/albums/cc295/mjydrafter/20130510_110902_zps0ccb7c4e.jpg)
Now, the fan does need to be taken apart on order to remove it without removing the rad. So first free the fan bracket, then hopefully your fan blade will be easier to remove than mine. Remove the fan blade, then the back cover of the fan motor. Flick the fan mount spring clips off, and it will all come out in pieces. Your hands may not be the same for a while afterwords, but it'll come out. :yes
I would assume the K100 wider rad. afforded me extra room to remove the fan and bracket.
I was able get my new fan and bracket put back in without any additional drama. You must wiggle it a bit getting it into place but no worse than any other parts. Since I used the original fan bracket to make up mine the fan fits right into place pretty easily. I ripped the rubber cushion/bushing on the upper mount, but this was actually a blessing as it made reassembly much easier.
I also took this time to insulate the fuel return hose and I also added my version of the Johnny blanket. I used the foil lined bubble wrap insulation. I also made my fuel return hose insultaion tube out of the same stuff. I used a strip of the isulation about 1' wide by 4' long. I just laid it in with a small slit up near the steering bearings, and holes for the the fuel tank rear mounts. One extra hole for the fuel pump electrics and ran it back just past the tool box above the computer. It made a noticeable improvement in the under seat & tank heat issues.
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Great info! Thanks for taking the time to educate us on our options.
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... I did a bit of research and decided that replacing the crap fan with the same crap fan was silly. ...
I don't necessarily think that the modular OEM fans are crap. They are simple devices subject to extremely high temperatures plus all the wind and rain that makes it through the radiator every minute that your bike is in motion. That's a lot to ask. I do wish the bike had some smart circuitry to run the fan for a minute every time the bike was started or shut off.
The $80 fan motor (http://www.euromotoelectrics.com/BMW-Motor-Radiator-Fan-K-models-1983-1995-p/fan-k427m.htm) is all that is necessary to replace to resolve a dead fan. The OEM fix is less complicated too since it does not require any customizing.
I suspect that your bike's previous owner may not have fully set the plastic blades onto the motor he replaced, hence the damaged radiator fins. I just replaced my fan motor and I know it took considerable force to push the blades back on to the motor, so much that I was worried about damaging the new motor. On a properly mounted assembly, the motor spindle should be flush with the front of the fan blade mount. Or maybe the two metal clips were on backwards which would create enough free play that the fan could touch the radiator fins.
How expensive was your Spal fan? Does it spin as fast as OEM?
I hope it works well for you.
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The Spal was ~$63 shipped with sales tax... nothing really complicated or custom about it, other than the simple bracket.
The original fan motor is less than robust. I was not impressed by the brush holders and the overall construction of the original fan. The Spal impresses me in every way, including being waterproof. Even if the Spal motor fails, the blades won't come forward drilling into the radiator. The blade is held on with a circlip.
The PO gave me the old radiator that he replaced due to it leaking. I suspect he didn't even remove the fan from the radiator (I did it last week, the screws were stuck pretty good). I believe he got the current radiator with the fan and never tested the fan motor. That fan blade had also drilled into the old radiator. I had taken it apart to see if I had an extra fan I could use without buying a new one.
When I disassembled the current working radiator, the 2nd junk fan had, drilled a bit into this one as well. It just hadn't gone into it far enough to cause a leak.
Even if my 2 fans and radiators are anecdotal, I've seen enough to know this modification is a less expensive, better alternative, than the OEM fan motor.
Obviously YMMV. :riding:
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thanks for the info. Saved me the trouble of finding a good alternative fan. The OE fan is one of the few weak points in old K's.
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I also made up a template for the bracket if anyone is interested. I will have to scan it at work on Monday, and it will be bigger than a 8.5" x 11", probably need to be able to print 11x17 or legal size.
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Add me to the template list, please. When time comes, I think I like your solution better than manual rewire (at least at my current skill level).
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I also made up a template for the bracket if anyone is interested. I will have to scan it at work on Monday, and it will be bigger than a 8.5" x 11", probably need to be able to print 11x17 or legal size.
Put me on that template list, as well please. Solid mod.
Thanks!
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I have scanned and attached a .pdf of the bracket I made up. I will see about making a better one, since I am a drafter after all. I will make up a new one as soon as I have a few free minutes. This one will work for now.
I traced my bracket in pencil, and then had to go back over the pencil with a sharpie so it could be seen. So, you may want to adjust it a bit.
I thought about adding holes around the edge, but I don't think that the bracket will block too much airflow.
I had to scan it in on an 11x17 sheet, so if you print it without scaling it "should" be to scale. I also added a CM mark and an inch mark so you can check it after you print it.
:2thumbup:
*Edit to add: I got the fan here, no affiliation, just happy with them and their service. Not to mention they are locals, so I even had to pay sales tax...http://www.universalpartsinc.com/HP_Parts.asp?CAT=SPAL%20FANS%20AND%20ACCESSORIES&SUB=6.5%20INCH%20ELECTRIC%20FANS (http://www.universalpartsinc.com/HP_Parts.asp?CAT=SPAL%20FANS%20AND%20ACCESSORIES&SUB=6.5%20INCH%20ELECTRIC%20FANS)
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OK. Potentially dumb question. What gauge/thickness/type of metal did you use for your fabricated mount? Looks like a great fix and is next on my list (the Herko fuel pump is chugging along like a champ!)
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Good question! I will measure it at lunch for sure, but IIRC, it was 3/16"
It was a cut up Handicapped Parking place sign... Now, look back at the pic with the cork gasket... :hehehe
And no, I didn't steal it. :neener:
:yes
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Any chance of a long-term report (now that you've been riding through the heat?). Any additional mods you would make in hindsight? Still debating this mod vs. replacement Bosch motor and a toggle. Having to get the mount fabricated puts them neck and neck $$$ wise in my case. Interested in what you've learned. Thanks.
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The fan is working fine, (I don't know that it's ever run in battle though) :dunno2:
I will test it one of these days, but I have no doubt it will work just fine.
I'm pretty sure the stock fans die from disuse just as much as anything. Although, the melted brush holders seem to be a common theme.
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+1 that the stock fans are crap, same radiator damage from the same "time to spool off the shaft and into something easily damaged"
My fan is JB Welded back onto the shaft, and the radiator is mended thanks to my local shop, but I think this upgrade is due this Winter once riding season ends and deferred maintenance season begins. Thanks for the template and the documentation!
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So I'm happy to report that I have completed MJYDrafter's mod pretty much step by step as outlined including using the bracket he drew up. I live in the Verde Valley of AZ. Surrounded by mountains on all sides. So lots of opportunities to overheat a fanless Brick. :curvy-road Over this summer, there are several drives where the bike would just hit red light on heat. So after the mod yesterday, I spend 4 hours riding all the runs that would cause the bike to get hot. It was 101 hear yesterday. And muggy. So at the end of the day, my Legendary Flying Brick never got to red light. I thought I could feel a little extra heat on my legs once or twice, though. So at the end of the run, I parked and kept the bike running. That fan is deadly silent! Standing w/no helmet I could not tell for sure by sound if the fan was on. I put my gloved hand down by the engine, and let me tell you, that Spal can really push some air! Extremely happy with the mod. Plus just a little happy with myself for doing the swap without having to take the radiator off. :bmwsmile
Excellent excellent mod by MJYDrafter. I would like to suggest that it should be written up and submitted to the Lieberry. It really is that good a deal. Just my two bits.
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so 18 months later, I've bought a K75 and its lunched the fan. How unsurprising. Was about to write up about an alternative fan and lo behold… its been done.
A second hand fan over here is 175 clams. found the above unit on flea bay for 50 clams. It should be here by the end of the week.
Then I can go for a ride early new year and post some pics of the country around this way.
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Well, after reading this thread, I'm taking mine apart to check it, then possibly trying one of the suggested fixes here. My bike has about 85,000 Km on it and likely needs this item to be addressed...
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:2thumbup:
Mate would have been a easier option...... Where were you ?????
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So I bought the same fan as appears in the first pictures in this thread.
I decided not to make a bracket to fit it up but rather take all the mounting tabs off with a flapper disc on an angle grinder.
I figured that the whole fan unit would go close to fitting inside the original shroud. Almost.
I removed the original motor mount and split one side of the BMW shroud to allow the new fan unit in.
Decided that things weren't quite lining up properly so split the other side after marking locations etc.
A small bead of silicone was run around the inside of the BMW shroud then the new fan unit pop riveted in place.
I also had to elongate the top hole about 4mm to account for a slightly stretched out shroud
The whole operation took about an hour…. not bad for a $50 fix as opposed to BMW wanting $400 for a new unit.
(http://i1250.photobucket.com/albums/hh522/OzRoadbandit/The%20Brick/IMAG3053_zps4b468c0f.jpg) (http://s1250.photobucket.com/user/OzRoadbandit/media/The%20Brick/IMAG3053_zps4b468c0f.jpg.html)
(http://i1250.photobucket.com/albums/hh522/OzRoadbandit/The%20Brick/IMAG3054_zpse6f06de6.jpg) (http://s1250.photobucket.com/user/OzRoadbandit/media/The%20Brick/IMAG3054_zpse6f06de6.jpg.html)
(http://i1250.photobucket.com/albums/hh522/OzRoadbandit/The%20Brick/IMAG3055_zps08e51d64.jpg) (http://s1250.photobucket.com/user/OzRoadbandit/media/The%20Brick/IMAG3055_zps08e51d64.jpg.html)
(http://i1250.photobucket.com/albums/hh522/OzRoadbandit/The%20Brick/IMAG3056_zps3a521e8d.jpg) (http://s1250.photobucket.com/user/OzRoadbandit/media/The%20Brick/IMAG3056_zps3a521e8d.jpg.html)
(http://i1250.photobucket.com/albums/hh522/OzRoadbandit/The%20Brick/IMAG3057_zps8123ba07.jpg) (http://s1250.photobucket.com/user/OzRoadbandit/media/The%20Brick/IMAG3057_zps8123ba07.jpg.html)
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^^^^^Hey, that's pretty clever! :clap:
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Even easier, Google "Radiator Fan Zip Ties"
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my fan came with those zip ties and I did consider using them.
My concern is they'll damage the radiator in a short space of time so went the other way.
Keen to hear if others have used them and if there have been any issues over the long term
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I used some of those on a radiator fan in a Jeep. I was not impressed with them. I think 2 of them broke.
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after just returning from a 2000km trip over the last few days, I can happily report the new thermofan does its job nicely.
Moves plenty of air. The bike had to cope with temps as high as 44deg… thats Celsius gentlemen or just over 110deg F in american speak.
It was a bit warm at times.
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It sure beats sitting in traffic, 2-up, watching the VDO temperature gauge slowly go up past 240 degrees...(I was slow to replace my fan)
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Pondering on the question of the fan on my K75 at the moment - I just checked with a long screwdriver and sure enough the blades do turn - but with the resistance described elsewhere (ie feels like the fan blade is just spinning on a seized shaft). This is the first time I've even checked the fan since owning the bike (although did not do that many miles over in the UK) and have never seen the over-temp (red?) light come on - even on longer rides. Perhaps the fan simply does not kick-in frequently enough to keep it healthy?
So I'm wondering if, in a generally cooler maritime climate such as mine (we do get the odd very hot day in summer - but typically 20 to 30c) there is enough cooling capacity in the radiator, without the fan? Of course in an ideal world it should be replaced and working ... but up to my elbows in other projects ie looking for an excuse to put this one off for a while ... probably not the first to have this thought!
Comments?
Gio
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So I'm wondering if, in a generally cooler maritime climate such as mine (we do get the odd very hot day in summer - but typically 20 to 30c) there is enough cooling capacity in the radiator, without the fan?
Under these circumstances the fan will kick in only standing still and slow moving traffic.
Turn the bike off at stand still, and avoid slow moving traffic when possible.
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Exactly - something I'm used to with the air/oil-cooled MG! I don't commute and live in a rural area so most (if not all) of my miles have and likely will be either highway or country roads - so as you say, if the fan never kicks in under these circumstances it may not be a surprise that eventually it seizes up through lack of activity?
Having said that, it would be nice to know that is was working if required ... hmmm.
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Let the bike idle until warms up and fan kicks in. Give it a shot of lube every so often. It will last if given care. Just another personality quirk of the Kbike.
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I think that would work if the fan was in working order, but from what others describe think mine has gone due to lack of activity, crud build-up etc. I know there are some jumper tests to confirm this but not got around to that yet. Yes - we all have our quirks - just need to recognise and accept them in return for the more numerous good points, right?
I'm thinking it would be nice to have a temperature gauge of some sort rather than just the red light - haven't researched that yet.
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Yup, the fan will only kick in if sitting in traffic. My fan wasn't working for most of last summer and I ended up running the bike pretty hot a few times. I have a VDO temperature gauge and got it around 235f. If the bike stays moving it likely won't get over 180f or so
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Interesting - (and apologies if covered elsewhere) - at what temp does the red light come on? I'll confess my ignorance in matters of liquid cooling as the K is the first such bike I've owned ... air is way easier to maintain!
Gio
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at what temp does the red light come on?
Fan kicks in at 103oC, warning light comes on at 111oC.
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Thanks Inge. So F14 - without your fan running on those hot days, at 235f you were only just above the temp at which the red light should show (111c = 232f) ... interested to know if it did or not?
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Red light came on a bit before then
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Mine was seized. I hammered back the 'tabs' to get it apart, polished the shaft, reassembled.
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i donts know nothing abouts motobricko fans and being in the red... unless if you are talking abouts the tach... butts i think i can make a positive contribution to the cause...
1st fan failure was beyond a hundert thou on the odo... the blade had come off the shaft butts was still turning broaching away my radiator finns... replaced it before it caused radiator whack... butts we were 2 up from sea lever to 10 thou feet of nearly all switchbacks... abouts 5 thou feet it went to the red... i pulled off... figger the problem and had to decide what to do...
we went until i thought the engine was gonna explode... the radiator cap never blew... butts we were pegged in the red for quite a while... replace the fan with a used oem with documented 33 thou on it... retired the moto at 150 thou on the odo without another fan failure...
so... 150 thou on the odo... 1 oem fan replacement...
2nd fan failure was near 95 thou on the odo... it was locked up... once again an hour minimum from civilization... had to navigate 30 miles of up hill switchbacks to getts outta there... was not as simple as being at 5 thou on the other moto where we just reversed direction and basically coasted down the mountain...
this was different... we were at the lost coast... no way out except over the hill... we would ride until it pegged red... pull off and let it cool down... once we made it out of there we had 400 miles of freeway... it was abouts 110 degrees out that day... i locked it down at 80mph and it hovered below the red all the way...
replace the fan with a used oem with documented 60 thou on it... this motor failed at 110 thou with no drama... one day at a light it went red... could not hear the fan... was locked up... replaced it with a used oem with 10 thous documented on it...
so... 2 oem fans and now 120 thou on the odo...
all together abouts 300k on motobricks... replaced 3 original fans with used oem fans at a cost of approx $120...
i gotts 2 used oem replacements that are like new low miles in the basement... figger should score a couple goods ones when i donts need them...
now to the matter at hand... i will idle them till that fan comes on on a regular basis... especially after riding in the rain or after a wash... im not worried abouts riding in the red... i thinks it will be ok when you can getts some air flowing...
j o
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That's not a bad record Johnny ... 300k / 3 fans = 100k per fan - that sounds like a reasonable average to me. I've yet to pull / test what I suspect is a bad fan from my K75s - and may get lucky (as bocutter sounds like he did) and get it running again - if not I may take the same route as yourself and see if I can find a working oem with low miles - PM me if you feel that one of those low-mileage in your basement is taking up too much room.
Ah yes - to get some air flowing would be nice - we are hunkering down for another expected snow storm tonight ... but spring will soon be here ..?
Gio
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I would've gone s/hand fan IF the price had've been reasonable
but at $175 ….. :yow
I politely declined and went had a bex, beer and a lay down
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I have a wiring question about this.
I'm at the point where I need to solder the old connector onto the Spal fan. Can anyone speak from experience which is positive and which is negative? The wiring on my bike has a brown wire, and a yellow/purple wire. I was going to assume that the latter is positive, but I really don't want to have to do it twice.
Thanks.
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In my manual If i'm reading this correctly br is neg and vg (violet green) pos. I'd probably put my volt meter on it to verify though or test light. Then i'd put the fan on a battery too to verify the direction. When I don't test everything before I complete something I always ends up doing it again :(
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*Edit to add: I got the fan here, no affiliation, just happy with them and their service. Not to mention they are locals, so I even had to pay sales tax...http://www.universalpartsinc.com/HP_Parts.asp?CAT=SPAL%20FANS%20AND%20ACCESSORIES&SUB=6.5%20INCH%20ELECTRIC%20FANS (http://www.universalpartsinc.com/HP_Parts.asp?CAT=SPAL%20FANS%20AND%20ACCESSORIES&SUB=6.5%20INCH%20ELECTRIC%20FANS)
Updated link to the fan:
http://www.universalpartsinc.com/shopping/productDetails.aspx?i=749937&c=10506
i think i'm sold on mjydrafter's mod.
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i had the mod done 2 weeks ago, using mjdrafter's mount that he sent to me from the US. The dealer did it for me as i had other time commitments to keep . There's no way to do the job without taking the fairing totally off. The fan is almost too quiet, but really sucks in the air. The dealer setup the low setting of my heated grips switch (at my request) as a manual switch for the fan, and it's proven useful once. So far, i like it a lot. But have only ridden the bike once since i got it back, but was on it for a while. When i ride it more and if i notice anything goofy, i will report back.
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I did the RoadBandit version of the mod to my K100RS back in August. After I got the fairings off it took about two hours to modify the fan bracket, mount the fan, clean out the radiator fins, and do a flush of the radiator.
With the manual override, I can sit in traffic and not have the temperature get scary. Going to do my K75RT this winter. Fan still works, but has a lot of miles on it. Doing it more as a preemptive fix before I have a hot weather problem.
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Having been shouted down by Gryph and Laitch, replaced near-dead fan with Spal 6.5”
Followed Roadbandit's approach above. Initially planned to use the plate but wanted it to appear original.
Suggestion: Plastic weld the original fan shroud with off cuts and large soldering iron. Pics should be self explanatory.
Notes:
When cutting the plastic or both old fan and new Spal, the solid masonry disc worked perfectly.
Keep the off cuts for welding.
Final cleaning up done with drum sander (cheapie from Harbour Freight etc) on hand drill. The larger drum gives a higher surface speed and easier removal of material. Smaller drums and final hand sand as needed.
The two gaps created after cutting / expanding the fan shroud can be quite easily filled with the two smaller fan supports. I reduced mine on a belt sander and heated to create curve. Shroud is clipped around new fan to eliminate play later.
Plastic welding: using a large soldering iron, I tried to create a vee between the joints and then fill with off-cuts melted into the space. I guess the idea is to create a vee from both sides that almost touch for proper penetration (mine could have been deeper). Leave some excess and remove with drum sander. This process is very easy with thick plastic – especially one that is really out of sight and wont get seen. Strength of the joints was surprisingly good – I twisted it a few times and had no issues.
Silicone: I had to throw two old silicone tubes away and using some grey crap. A final coat of black spray hid it satisfactorily.
Will follow wiring diagram on this forum and will use second-hand original BMW switch for impact pad.
Hope this is of some use
Regards
Guy
Question: How to lubricate the front bush on the BMW fan? Back one is easy to get at. The fan blade seems stuck on the shaft daring me to break it free.
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Wow, nice job VNM!
I wish I had the patience to do such a detailed retrofit. From what I have heard about the Spal fans, this is the last you'll have to screw with the fan on that bike.
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I virtually did the same mod on mine with the exception I used a Davies Craig fan ( fully sealed) with OEM blades. After cutting off the excess outer rings from the new housing and the mounting arms of the OEM. I found that the outer ring on the new housing lined up with the OEM housing, so I just made some tight "U" clips and riveted it on. I also added a bypass switch and it has not missed a beat in 18years.
Regards Martin.
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Here's an easy fix for the fan motor ....
http://www.ebay.com/itm/FIT-FOR-Bosch-Mercedes-Benz-blower-motor-0130007027-0130007305-NEW-1-PS-KIT-/152209925212?hash=item23706b245c:g:by8AAOSwZVlXtRy2&vxp=mtr
Don in Nipomo
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The problem is that the Bosch motor is crap with melting brush holders and replacing with another Bosch motor is a bunch of work to guarantee the same problems down the road. The Spal is a superior fan and can be had for only 15 bucks more than the Bosch motor alone.
The Spal is so easy to retrofit that it doesn't make sense to go with the OEM or Bosch fans.
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It's a replica of the Bosch produced in some Asian country. They did make some subtle changes and improvements.
I carefully examined both when they were on the bench.
The fit is simple enough even I could do it. It's a legitimate option.
We'll see if it lasts, mine was $40 including shipping. Came out of Latvia when I purchased it last April.
Don in Nipomo
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If you really want to keep your machine original and decide to use the Latvian fan, be very careful when you are pressing the fan blades onto the shaft. One of the problems seen with the OEM fan is that the blades slide on the shaft moving forward enough to damage the radiator causing coolant leaks.
From personal experience and as noted copiously in this thread and in other threads and forums the OEM fan is a piece of sh!t with seizing bearings, melting brush holders, and blades slipping. It doesn't make sense to me to stick with that design when the superior Spal fan is so cheap and easy to replace it with.
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..........When i ride it more and if i notice anything goofy, i will report back.
It's been 1 year since my last post about the Spal fan mod. i'm just reporting back that there have been no issues at all. Still going strong.
:2thumbup:
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so just fixed my k75 87 bad ground now its overheating, has enough fluid fan seems to run than seems to cut in and out overheating light comes on and off with how fast or how high the rpm is. so sensor relay fan what else could it be? only 65f here in Chicago area, will be a problem when it's 80f
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Can you start a thread in the workshop section. It will make it easier to follow, and won't clog up this older thread.
What is the history of the bike? How many miles? What is the general condition? Has it been neglected by a previous owner? How long have you had it? Has the cooling system been flushed? Is it actually overheating, or is the sensor confused? Is it a coffee racer?
You shouldn't need the fan this time of year. My first guess is that you may have a spot in the temperature sensor wiring where the insulation has worn through and the wire is shorting to the frame. A short to ground looks like a very high temperature and can turn on the fan. That it is intermittent makes me think of something rubbing and bouncing around.
It is also possible that your water pump is bad and not circulating consistently. I think this was a problem on earlier pumps, but I have no experience there.
Anyway, please post a new thread.
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what else could it be?
It could be you don't have as much coolant as you may believe. How did you check it? How old is the coolant. The radiator cap might be losing pressure. The thermostat might not be opening. Those are worth a check.
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I have scanned and attached a .pdf of the bracket I made up.
Thanks very much for the pdf, I finally have a good use for it...
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well thanks for all of the suggestions about my over heating. I tested the thermostat and it was good, very twisted gasket on the radiator cap, measured the fluid that I took out and it seemed to be at least only seventy percent full I can't test the overheating until I fix this yet another problem with a thirty year old bike 87 k75, but my battery lost it's charge, took it back to batteries plus they charged it over night and it was fine, BUT when I connected the battery terminals, with the ignition off the starter turned on and would just keep running, have no idea what to do, put in new starter relay but it was a bad ground cable from the battery to the motor wow, I have no ideas here, HELP
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Pull the starter relay and pop off the cover, you will find that the points have welded themselves together. Separate the points and file or sand them flat and reassemble. Bricks are known to have this problem which occurs when you have low battery voltage. In extreme cases the battery can actually blow out. You can install an isolator switch, installation is posted or sometimes rapping on the relay will free up the points.
Regards Martin.
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thanks Martin, I met a guy named Martin at work he was limping so I asked him if his foot was ok, he lifted up his pants leg and he had no foot. will try the relay and get back to you
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Wasn't me I've got two feet last time I looked. Keep us posted.
Regards a two footed Martin.
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Up date, thanks for the information about the brand new 120usd relay, checked continuity and it was on, taped on it and lost continuity, it fixed the problem. I was going to take a ride to watch some girls softball but it's a bit chilly north of Chicago today, will ride over the weekend it's going to be nice, will see if she overheats. Thanks again for all the help, will chime in later about the overheating fix.
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So with my relay fixed and my battery charged went on my quest started last summer to find the best Corn Dog I can find. Today Lefty's, and no problem with my overheating, at least no indicator light. It was very warm and windy here north of Chicago today. and I could feel a lot of heat on my right leg, never noticed that before, but I have only owned this bike for just over a year., I am thinking it is normal. Thanks for all the help. The Corn Dog was tied for the best yet, but I learned that Springfield Illinois is the home of the first Corn Dogs, actually Cozy Dog, about five hour drive south.
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(https://s3-media3.fl.yelpcdn.com/bphoto/-d_ASMvTimH_IjNT6hwz2A/ls.jpg)
Sorry, replaced fluid it was low new gaskets on cap fixed over heating.
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Thanks for the overheating fix followup and corndog facts!
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FYI only - 10 years have passed, and still NO ISSUES with the Spal fan.
icon_cheers