This Is The EPIC Soggs 92K75 MAGA Thread

[daveson]

Also soggs look at the colour codes on the four pin on both sides of the plug to to verify to others. 

[Soggz]

There are some great suggestions here.  Gryphon is right,  the gear indicator's connector is exactly like the tank one,  so it is easy to mix up and that would explain your no crank situation.  Also do the easy stuff first,  dry the plugs and charge the battery,  a new battery does not mean a fully charged one.  If you still have the trouble persisting,  DO NOT disconnect the fuel pump by it's connector but removing the corresponding fuse.  If still no luck,  you can try everything else suggested.

the plugs are the same granted, but this one is plugged into a plug with the same colour wires so it can’t be a mistake.

[Soggz]

Ok guys,had a spare half hour in the garage.
Here's where we're at...
First of all,I confess,I'm an idiot.
Bike cranks with the tank plug disconnect.
Ok.
Plugs have been out all night,put them back in.
Cranked bike,bike tried to start,or rather,coughed a bit.
Pulled the tps off while cranking,and it tried to start again,smelt fuel.
Took the plugs out and dried them off,then replaced them.
Cranked it over and it tried starting again,only this time it did for another 4 seconds,then stalled.
Again,stank of fuel.
Too much fuel?
Took plugs out and dried them with a blow torch,disconnected fuel tank pump.
Bike started easier,as plugs were hot, then died again,( I thought it may have been due to lack of fuel as pump disconnected ).
So I'm thinking...
Too much fuel?
Could it be the fuel pump thing on the back of the throttle bodies has given up?
Not sure how it works. I just know that the po had stored this bike away as a working bike,and I guess everything just sort of deteriorated on it over time. The pump in the tank was pretty mushy,could the little pump on the bodies be in a bad state too? Is it a mechanical thing that needs replacing time to time?
Thanks for your patience,guys,on this ever growing,epic long thread due to my ability to not understand 80's German fuel injection systems!

[Soggz]

I think a lot of people here are struggling to believe that your bike cranks but if you disconnect power to the fuel pump it won't crank,  is that truly the case,  will you say it categorically.

Then post some photos, then you might get help. While waiting look at the diagrams.

I'm not good with electrickery, this one's beyond me.

my mistake...it does crank...

[Soggz]

Sidestand, neutral, clutch...  What cha got.

still don't run.

[szabgab]

Ok guys,had a spare half hour in the garage.
Here's where we're at..
Took plugs out and dried them with a blow torch,disconnected fuel tank pump.
Bike started easier,as plugs were hot, then died again,( I thought it may have been due to lack of fuel as pump disconnected ).
So I'm thinking...
Too much fuel?
Could it be the fuel pump thing on the back of the throttle bodies has given up?
Not sure how it works.
Thanks for your patience,guys,on this ever growing,epic long thread due to my ability to not understand 80's German fuel injection systems!

It runs,  even if it does for a short period,  that is the main thing. Running too rich could be I guess many things,  however what you think is a secondary fuel pump is the pressure regulator.  Read through the excellent pdf again that was posted here a while back and that explains the operation of the whole system ina great and understandable way.  Also try to think through,  what exactly has been done to the bike,  since it run,  if I remember correctly,  you had the MAF off,  hopefully the temp sensor was unmolested? Also whilst doing the compression test,  did you do any leak down tests too?  If so,  you could have oil in the cylinders too. Whilst cranking with pump connected look inside the tank,  if all is well,  eg pump buzzing and a steady stream of fuel is being pumped back.

Try to start the bike with no. 6 fuse removed and plug it back quickly,  once the bike started.  Try to run it for a bit,  probably revving it, and so on to see,  if the system clears...  Apart from that I'm clueless,  but others will have some better idea,  if still the same happens

[Soggz]

It runs,  even if it does for a short period,  that is the main thing. Running too rich could be I guess many things,  however what you think is a secondary fuel pump is the pressure regulator.  Read through the excellent pdf again that was posted here a while back and that explains the operation of the whole system ina great and understandable way.  Also try to think through,  what exactly has been done to the bike,  since it run,  if I remember correctly,  you had the MAF off,  hopefully the temp sensor was unmolested? Also whilst doing the compression test,  did you do any leak down tests too?  If so,  you could have oil in the cylinders too.

Try to start the bike with no. 6 fuse removed and reconnect it quickly,  when the bike started.  Try to run it for a bit,  probably revving it, and so on to see,  if the system clears...  Apart from that I'm clueless,  but others will have some better idea,  if still the same happens

Hi.
Yes, tried the fuse 6 thing. Didn’t really make a lot of difference. I didn’t touch the sensor in the maf, just looked at it, confused.
Havnt done a leak Down on it, as I don’t think I have the tools. What do I need?

[Soggz]

greetings...

like a dog needs a bone...

j o

Thanks. That’s helpful.

[szabgab]

Hi.
Yes, tried the fuse 6 thing. Didn’t really make a lot of difference. I didn’t touch the sensor in the maf, just looked at it, confused.
Havnt done a leak Down on it, as I don’t think I have the tools. What do I need?

Soggz,  sorry,  also check for correct pump operation,  I have added info to my comment above...

Leak. down test is just an extension of the pressure test,  you have done earlier.

[szabgab]

I do not want to sound,  like a complete twat,  but be methodical and don't mess with random things at the same time,  otherwise you will never know,  what made matters better or much worse.  Try to. make  a list of things,  you have worked on,  so you can check for correct operation,  e.g your MAF might not be connected correctly,  the air bypass on the MAF has bren misadjusted,  your water temperature sensor -  although checked for fan operation,  you should also check for correct resistance at the computer,  etc.
This is for K100 bikes,  but the basics are all the same https://studyres.com/doc/23076605/k100-troubleshooting..---hrsbstaff.ednet.ns.ca

[Soggz]

Hi. The spark plugs are from Motorworks k75c service kit, so I’m guessing the right ones. They are tight to pull off and the tips are bare tips, not threaded or threaded with separate caps that screw on to them.

[daveson]

Have you got a workshop manual?

Horn,  load, swapped? Test them as well,  like the FI test

Light out while cranking?

Fuel returning to tank? - it,s easy to see with the cap off.

FI relay test?, if not sure can someone do it for you?

These are all quick easy tests.

Post photos (I don't know how to do that either) or get help with that, and I'm sure you will get more help.

[Soggz]

Have you got a workshop manual?

Horn,  load, swapped? Test them as well,  like the FI test

Light out while cranking?

Fuel returning to tank? - it,s easy to see with the cap off.

FI relay test?, if not sure can someone do it for you?

These are all quick easy tests.

Post photos (I don't know how to do that either) or get help with that, and I'm sure you will get more help.

Hi. I’ll look tomorrow, as it’s getting on. I have to help my middle son with homework.
Thanks again.

[daveson]

Fuel in the vacuum hose at cylinder three?

Are all three cylinders wet?

I had the same overfueling  problem once, I replaced the FI relay and it was problem solved.

[Soggz]

Fuel pump relay, do you mean? If so, which one, as there are 2. One like the horn relay, and a bigger one, according to this.

[Soggz]

Fuel in the vacuum hose at cylinder three?

Are all three cylinders wet?

I had the same overfueling  problem once, I replaced the FI relay and it was problem solved.

is the FI relay, the fuel pump relay?

[Soggz]

True dat.

How about the horn and load relays,  did you swap them? Does the headlight now go out while cranking?

Another quick test put bike in third,  roll back release clutch. Do it a few times. Now what cha got?

The FI relay is a quick test too.

whats a ‘load’ relay? Is it called something different?

[daveson]

First,  does fuel return to the tank,  its a two minute job,  you can see it dribbling from the top of the tank to the fuel level.

Sorry,  I should have said fuel pump relay.

The picture is labelled wrongly.

The top left is the fuel pump,  load shed in the middle, horn on the right.

Does your horn work? Does the light cut out while cranking?

Swap the horn and load shed, does the horn work? Does the light cut out while cranking?

I think your load shed is not working,  but clean the pins,  push them in and out five times and try again.

Push the fuel pump relay in and out five times, clean the pins. Try again... No go... Test the fuel pump relay.

[Soggz]

Hello All.


Ahem.
I'll keep this short.
I have a k75c.It was sat for 12 years,in a garage,in the dry.
I bought it,it wouldn't run.
I've put in a new fuel pump
New filter and mesh
Had the injectors cleaned
New crankcase pipe and vacuum pipes caps
Cleaned the throttle bodies out
New CHARGED fully battery
Cleaned all connections
New fan,too...

Now.
I had it running briefly,even went for a short ride on it,but it was really rough.
Limped home on it,did a compression test,all good.serviced it with new oil,filter,plugs,air filter.
Still rough,won't even idle now.
Plugs are wet,dried them out,reinstalled.
Starts,but only for a few seconds,then stalls.Plugs are wet again...
I've been told by a very helpful person on here,to maybe change the horn relay out with the fuel injection relay,as they are the same(?), just to see if that helps,as I know the horn relay works.
I will try this tommorow,as the battery is now discharged with my attempts to try and start it.
Thank you.
Photos to follow... ...

[Soggz]

It’s on charge now.

[Soggz]

Thanks.
Yes. Ignition on,no pump noise until starter is pressed,bike cranks. Finger off of the starter,and you can hear it whirring for about a second or so,then it stops making a noise. The pump works.I havnt tried with the front light on.I will try tomorrow,as its late in England now.


Thanks.

[Soggz]

It appears that you are dealing with a gross overfueling situation here. 

You have looked at almost everything on the engine with the exception of the engine control unit(ECU) and the signal to the injectors.  The fact that your engine is drowning in fuel indicates that the fuel pump is working.  If there is a problem with the fuel pump relay, it is that it is stuck ON and the pump is running all the time the ignition is on. 

Before you start trying to swap relays, open the tank, and while listening closely inside the tank, turn on the ignition.  There should be NO NOISE from the fuel pump.  With the transmission in neutral or while holding the clutch lever in, push the starter button briefly, just enough to bump the starter motor.  You should be able to hear the pump run for a second or so and then stop.  If this is the case, your fuel pump and relay are probably okay.  Don't mess with them anymore.

Next, make sure the headlight switch is turned on.  With the transmission in neutral, the clutch pulled in, and a fully charged battery, turn on the ignition and push the start button.  The headlight should go out while the starter motor is running.  If it doesn't, there is a problem with the load shed relay.  If it does go out, the relay is okay.  Don't fuck with it.

For now, these are the only tests you should be doing.  Focus on just these tests.  DO NOT BE DISTRACTED!

Hi.
Headlight goes off when cranked over with a fully charged battery. I’m pretty much guessing that the ecu in funked!
I found one on fleabay for £30.00, so I ordered it up.
Always a bit sceptical about 2nd hand electrical items, but if it runs with it, then great. I guess we will see. Should be here next week somewhen.




And thank you, again.

P.S...is there a pic anywhere of all the earths on a k75, please? I think I cleaned all of them, but I want to make sure I havnt Missed any out.

[Laitch]

is there a pic anywhere of all the earths on a k75, please? I think I cleaned all of them, but I want to make sure I havnt Missed any out.

Please tell us all the locations you have cleaned.

[Soggz]

Please tell us all the locations you have cleaned.

ok.
So far, electrical connections on loom.
Earth under tank, middle of frame.
Gearbox bolts to frame. (They are earths,I think I read). Is there more?

[Laitch]

That seems like good coverage. The starter cable connection and its mounting bolts should be in good condition. Inspect them.

After that return to the Mighty Gryphon's Reply #6 and inform us of the results of the tests in that post he suggested you try.