We just purchased an '82 244, non-turbo with 121k miles on it. It has had various repairs done in the past. Some appear to be well done, some appear to be done by Yabboes that shouldn't be allowed near tools.

On of the first thing to address was the intermittent stalling. After some research on the board I went to check out the 25 amp fuse by the battery. Fuse? What fuse? Instead somebody had cut it out and done a really crappy butt splice using pliers to crimp with. There was lots of corrosion and the butt connector showed serious signs of overheating. Ahhh, this will be easy. So I cut things back, put a nice marine waterproof fuse hold in, and used heatshrink butt connectors. (I'm a marine electrician so I figured I'd treat it like a boat.) Took it for a 20 mile test drive and no problems. Great.

Fast forward to this evening with my wife in the car. About 1/2 mile from home, bam, no power to anything, leaving us dead, in the dark, at a busy intersection. The main 25 amp fuse was blown.

So obviously I have a short circuit somewhere. I know that there are a lot of places it could be. I'm hoping that maybe the collected wisdom of the board may have some suggestions as to the most likely spots to check first. Obviously it must be upstream of the main fuse block as nothing else blew. It is also clearly intermittent and for the most part is fine. It does not seem to be related to bumps. It has, in the past, cut out on perfectly smooth road.

Thoughts would be greatly appreciated.

Thanks,
Jim

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Jim McCorison - '82 244 121k

Doh!

It appears that I went and happily jump off the cliff of assumption.

I kept reading about the infamous 25 amp fuse that is located just behind the battery. One thing that I never clicked on is that this is only on LH Jet cars. Mine is a K Jet. There isn't supposed to be a fuse. A previous owner had the battery cable replaced with a local auto parts special which just has a main high amperage lead and a secondary low amperage lead. When it was installed it was butt spliced to the wire from the junction block next to the battery. I _assumed_ that somebody had removed the fuse because of various problems. So installed one. Big oops. 100% of the current, except for starting, for a K Jet car flows through that lead. Peak loads are 35-40 amps, or possibly more. Clearly a 25 amp fuse isn't going to have a chance.

Further examination of the wiring diagrams show that there is no fuse protecting the headlight and ignition circuit and a couple of others. My thought is to remove the fuse block I put in and replace it with a 50 or 60 amp fuse block. There are nice marine ones which take a Maxi-ATC. Any opinions on that? I hate the idea of un-fused wires running around the engine compartment.

Cheers,

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Jim McCorison - '92 740 Wagon 156k

Fuel Pump Relay and Fuel pumps would be the next place to go.

That corroded butt splice was like a huge 150 amp fuse and quite possibly that hid the current draw issue the new fuse did not.

Stick another fuse and measure the current would be my next step.

Good Luck,

Paul

It turns out I have two problems. Well, actually, I probably have lots more than that. But two problems that I'm trying to deal with.

What started this whole process was trying to figure why the car would periodically cut-out, or die and easily restart. Upon further investigation I've found that part of the engine wiring harness was replace. Unfortunately by somebody without proper tools. The splice at the passenger side firewall had 5 loose crimps, one that just fell out of the connector when I moved it, the other four came out with only the slightest of tugs. I recrimped everything and the cutting-out problem seems to be fixed.

The "short" appears to be more one of excessive load that a short. I replaced the 25 amp ATC fuse with a resettable 30 amp ATC circuit breaker and went for a test drive. Half a mile down the road it popped. I had the headlights w/highs on and the rear window defogger. I turned off the lights and defogger and went for a drive and all else proved ok. So back home for some testing.

I clamped a current probe over the fused line from the battery. What I found is that the car draws 12-14 amps when the engine is running and everything else is turned off. That number jumped right out at me as being way to high. Does anybody know what a B21 non-turbo engine should draw?

It sounds like Paul's suggestion to check into the fuel pumps is the next place to go.

Cheers,
Jim
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Jim McCorison - '82 244 121k