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Old 03-15-2010, 03:07 AM   #1
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Default Electric problem - need help

I think I managed to run 12V thru my clutch line.

First startup of the year, all was well. She started right up and I drove the car 1h to my parents place. As I was comming of the highway, I had no clutch. The steel spun clutch line was leaking. Car then wouldn't start (trying to crank the car on 1st gear to move it). Towed home by dad. Started with jumper cables. Later turned out battery actually was ok.

This weekend I was back to change the clutch line and some other things. Nothing electric. After repair, the car wont start. It is as if the battery is low (of course it isn't, we charged it AND tried with jumper cables) and the engine is turning over very veeery slowly. Electrics are stock, except a FIA-kill switch in the dash. We excluded this by grounding the battery in the trunk again, as stock.

- As I turn the key the stock oil pressure gauge moves to 2o'clock (past standard pressure)
- My newly installed clutch line got HOT, which is why I guess I lead power thru it

So I am I guess that I in both cases spilled brake fluid on the starter and managed to ground it with the clutch line, is some strange way. But there is a 2.5h drive to my parents place from my new place, so I need a todo-list for the next visit.

Advice please, from the electric gurus.
/T.

Last edited by Torkel; 03-15-2010 at 03:17 AM.
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Old 03-15-2010, 03:16 AM   #2
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yeah something is grounding out first bet is the starter after that i would geus a stray fraid wire.
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Old 03-16-2010, 06:35 AM   #3
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Thanks for the answer. Could someone that is more skilled in electronics then I am (which shouldn't be hard to find) give me some more pointers? Of course I plan on lifting the car and checking the starter connections, the wires in the area, all ground point and so on. But if I don't find anything obvious, then where do I start? Could the oil pressure gauge not be a clue to the problem area? All the fuses are intact, btw.

Thanks in advance,
/T.
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Old 03-16-2010, 01:49 PM   #4
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Well, current is free to pass from the engine, through the clutch line and to ground, regardless of whether or not any brake fluid was spilled on anything. The starter goes to ground through the engine block, which is connected to the transmission, which is connected to the slave cylinder, which is connected to the clutch line. Normally, clutch lines are rubber and, thus, non-conductive. Since yours is metal, it could very well continue up to the clutch master cyl, and from there to chassis ground. This would have the effect of making it very hot.

(Incidentally, brake fluid is not at all conductive- it's chemically very similar to transformer oil, which is an excellent insulator.)

Best bet here is that the ground strap which normally goes from the engine block (on the exhaust side) to the body is damaged or missing. There's also supposed to be another ground strap towards the rear, from the PPF to the body. If both of them are not doing their job, then things like the clutch line and the throttle cable will start being the least resistive path to ground. The symptoms you describe fit this theory.

Go to the auto parts store and buy a generic pre-made ground cable. They're on the pegboard with the battery cables. Attach one end to the engine block and the other to the body. Make sure you've got a good, clean surface on both sides, free of paint, dirt, etc.
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Old 03-17-2010, 08:45 AM   #5
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I see what you mean. Makes a lot of sense. I will shift my priority from the starter to the main ground-strap between engine and chassi when I get back to the car. I believe there is one strap in the rear to the Power Train Frame as well, right?

Thanks for the help, Joe.
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Old 03-17-2010, 01:27 PM   #6
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Quote:
Originally Posted by Torkel View Post
I believe there is one strap in the rear to the Power Train Frame as well, right?
Yes. There should be two ground straps. One bolted to the engine block (or perhaps the head) on the same side as the exhaust, near the back. The other attached to the Power Train Frame (PPF) on the same side of the car as the intake manifold, just forward of the differential.

My guess is that these two straps are either broken, damaged, missing, corroded, loose, or the spots they are connected to are dirty or corroded.
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Old 03-20-2010, 10:08 AM   #7
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It's alive!!

I found no problems with either of the straps. Removed, cleaned and put them back again to no result. But I was convinced that the problem was bad ground, so I tried adding a extra big bad grounding strap from the block to the chassi. Car fired right up.

I also noticed that there is a difference between the new and the old clutch line - the new one has an extra layer of plastic outside the steel. I think the old clutch line has worked as ground for quite some time.

Anyway - she is back up and running! Thank you for the help!
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