1995 K75 Rehab after 32K miles

[Laitch]

Posts #10 and #11 in this 2015 thread are relevant to your plans. I'm supplying the link in case you, or anyone else, hasn't read them. Pin #45 in the text actually refers to pin #15 on the relay and is likely a typo in the diagram.

[Cinderedblock]

I haven't started jumping things but I encountered a mystery switch behind the temperature  sensor with two wires and 3 positions. It doesn't force the fan on so I'm about to chase it.

[Cinderedblock]

Mystery solved, that is an ignition switch bypass. It jumps out the key

[Laitch]

Good catch! That could be contributing to engine's bucking problem.

[Cinderedblock]

I probably should have listened to considering the engine, I found no issues in the cooling loop.

I'm going to replace the hall effect sensor. I understand they fail under heat and the forum post discussing it matches my description "Bucking Bronco". I also don't think anything I've tried so far would explain such a persisting intermittent issue.

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Please link any helpful resources for installation. All I know is to mark it and make sure I install it identically.



On another note I have found more things

The seal on my gas cap is gone, new on order.
 Tank was 1/8 water, this probably happened due to me hosing the tank off several times these past few days. The fuel pump is "functional" but missing a mounting clip and I don't think it's OEM, the terminals for the power wires look different. There is a hose clamp involved too. Interesting
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The power saver relay was super glued in it's socket. I cleaned the glue so it's a little loose but I'll put a ziptied on that like a professional.
 
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There may be more electrical tomfoolery

[Laitch]

The fuel pump is "functional" but missing a mounting clip and I don't think it's OEM, the terminals for the power wires look different. There is a hose clamp involved too.

That pump is a mess and could be part of the bucking problem because the fuel sock is partially clogged. Also, it probably doesn't have a low enough protrusion into fuel from its position in the holder. You can do better than that one without paying OEM price. The glue-spattered connector should be replaced if you can find one on ebay or in salvage.
I'm not convinced the Hall sensor is the problem because I'm uncertain this relic has been ridden long enough to get hot.  Have you done the static LED test on the sensor to determine if it's working at all?

[Cinderedblock]

The fuel pumps access to gas would be easy to troubleshoot. But now that you mention it I can't say I've tested. If that's all it was Ill loose my mind. I never had problems when the tank got low enough for the fuel light to come on several occasions.

Can you help me identify the orange relay, I've got conflicting information, I seen it labeled fuel pump relay and power saver relay.


I pulled the fuel filter and the sock. The sock didn't have anything in it, just discolored in the picture. The fuel filter didn't have much problem forcing gas through it so I put it back for now. I didn't have a replacement on hand.  I should probably check the pressure, haven't inspected the regulator.

I have not tested the hall sensor and I dont dare try. I'm not convinced either but my symptoms feel similar. I looked at my ground connection at the transmission and it was incredibly corroded at the bolt so I  cleaned it up.


I'm just waiting to take it for a ride and gather more information when it fails next.