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Odyssey
20-10-2008, 05:29 PM
Hi all - had my 1990 1.8 passat GT (8v) for 14 years and never needed help before, only had niggling probs. However it's now done 160000 miles and is getting a bit tired, still runs quite well but burns oil, (engines's never been opened).

The problem is it suddenly won't start, it's been getting reluctant to turn over for a while, battery is OK, usually starts OK when cold (but cranks slowly sometimes) I can drive 20 miles with no electrical load, stop and then it won't hardly turn over at all.

Been having to use a booster pack or even bump start, when it fires and runs immediately.

Alternator produces 14v, belt's tight, battery showing 12.7 - 13.2v.

I thought it was probably starter motor brushes, took it off at the weekend, couldn't get the endplate off (does it come off?) but as far as I could see the brushes were OK. Cleaned and replaced and it seemed better.

Today however after starting 3 or 4 times, it suddenly refused to turn over, no solenoid click, nothing. All lights and other elec gear work.

Applied 12v to motor terminals and it runs, power to solenoid terminal and it clicks.

Question is:- Is there a relay for the solenoid and if so where/which one is it.

Before I start pulling the motor again I'll check to see if power is getting from the switch to the LT on the solenoid and if not then I'll know where the problem lies, (but not necessarliy how to fix it).

Any guidance or ideas will be appreciated.

TIA - Alastair

zollaf
20-10-2008, 05:35 PM
try placing a jump lead from the - on your battery to the engine block. if this solves the problem youve got a dodgy earth. the solonoid is part of the starter and not replacable on its own. if the jump lead trick doesnt help then it might be time for a new starter motor.but then after 14 years i think its served you well.

zollaf
20-10-2008, 05:38 PM
no relay for the solonoid is what i meant to say, the solonoid is connected straight to the battery..

Odyssey
20-10-2008, 06:22 PM
Thanks Zollaf - some progress, I've had the voltmeter on the LT feed to the solenoid and there's 12.25v when you turn the key.

There's also no resistance across either of the main battery leads (and they're both 'direct', no joins), so that rules out bad earths.

I've pulled the starter and taking it apart to see if I can find anything, but applying power, it runs and the solenoid works . . . It's weird - I feel I'm missing something . . .

I agree - the car doesn't owe me a penny, and it wouldn't really be a problem but my wife's Range Rover blew a head gasket (or cracked a bore) last week, so we are 'automotively challenged' to say the least!

Alastair

zollaf
20-10-2008, 06:30 PM
i would still try the jump lead from the neg to your engine block. it can show up no resistance at all , until you try and put 250 odd amps through it. bad luck on the range rover. a 4.6 litre i presume?

STEWY L
20-10-2008, 07:10 PM
has your battery got plugs on it to top water up with?
if it has,remove them and wearing goggles/safety glasses,observe the cells as someone is cranking it.if you see bubbles in any one of them it's a good guide that you need a new battery.
if the starter/wiring/relay were at fault,it wouldn't crank any better when you put the booster on it, but if it it cranks with the booster on then the starter system must be ok,
i would have thought.

Odyssey
20-10-2008, 07:36 PM
Zollaf - it's the 4.2 Classic LSE, short motor about 2000 . . ., I may try one of the gasket/block sealers, Steel Seal gets some good reviews, for 50 it might buy me some time.

Anyway I have the starter fully disassembled, cleaning and lubing, no obvious problems. I'll put it back together and replace it in the car tomorrow and see if it's any better. I'll try the jumplead trick, is there another earth strap for the engine block hidden away somewhere?

Stewy - I had a drop test on the battery done a couple of weeks ago, it's OK, not brilliant - but OK. There's no cranking happening at all so I can't do that test, but jumping it from the extra heavy duty batt in the Rangie made no difference, so in all probability it's a prob in the wiring/earths as zollaf suggested.

Thanks for the suggestions.

Alastair

Odyssey
21-10-2008, 12:39 PM
Update - it's sorted, amazing what a taking apart and a good clean will do, put it back together and it cranks perfectly well.

Thanks for the suggestions, maybe it'll be another 14 years before I need more advice (but somehow I doubt it . . .)

A