Hi everyone
I'm starting to suspect the problem with my old Golf GTI is more serious than I thought. It has definitely got more rattly the last couple of times I drove it, and I have noticed the following:
At around 2000 rpm on a trailing throttle, the oil pressure shows 45psi. The moment I apply power, even a tiny amount, the oil pressure drops 8-10 psi, then recovers as the engine speed increases. If I accelerate then lift off the throttle, the oil pressure increases the moment I lift off. If I 'feather' the throttle, gently opening and closing it, I can get the oil pressure gauge to move up and down without any significant change in the engine speed.
It's a mechanical gauge: I reckon that under power the crankshaft is being forced downwards by the action of the conrods, away from the oil feed holes in the journals (hence the drop in pressure). And if there's enough slop in the main bearings to do that, I've got a major problem.
Unless anyone has a less expensive explanation?
Richard Hall
bangernomics.tripod.com
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Richard,
Been lucky enough not to go into the bottom end of one of these, so no expert but...
Oil pump? Is this on a splined drive...from a skew gear?
Could it be that the drive is slipping (remember the 2.8 V6 Ford?) when you apply revs due to...
a) The pump resistance causing a worn drive to slip when you increase revs and then "catch up" as you back off again...like a slipping clutch might.
b) Could wear in the engine cause movement of the intermediate shaft (or whatever) such that the correct engagement with the oil pump drive is pulled out under power...i.e excessive endfloat or something.
Or could the pressure relief valve be doing something odd?
Sean surely will *know* this one anyway.
In any case sump off this weekend before she blows???
M.M
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Unless anyone has a less expensive explanation?
You didn't specify 'sensible' so, it's actually a vacuum gauge?
(given the description, it behaves remarkably like one!)
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You didn't specify 'sensible' so, it's actually a vacuum gauge? (given the description, it behaves remarkably like one!)
I'd had that thought :)
Sad thing is, I bought the car specifically for track days - it's got Bilstein shocks, Tarox cross-drilled front discs and a few other useful bits. The engine was allegedly reconditioned 10,000 miles ago, but it looks as though something wasn't done properly. No way am I taking it onto a track until I've had the engine to pieces, and that will have to wait until I have evicted my old AX from the garage (it's been waiting for a new head gasket for two months, poor thing). Then there's a Dodge Charger awaiting new cam followers, my girlfriend's TVR needs all its front wishbone bushes changing, the Trooper is due an oil change in the next couple of weeks... I think I'll have to give up work, just so I have time to keep on top of the vehicle maintenance.
Richard Hall
bangernomics.tripod.com
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Hi Richard.
I had a good look at your website and was most impressed. I am a Yorkshireman.
You may be surprised at how few people here are still familiar with the Mk1 Golf.
The best person to get the advice from is currently horseriding in Boppard, somewhere along the Rhine.
I have looked in the Library, and a few manufacturers made the pump, including Febi and Bilstein. It's an ordinary gear pump.
People are saying that low pressure may mean good flow with large bearing gaps, or a u/s pump or clogged screen.
It may blow up, or run very well.
I just cannot help you for 17 days yet, sorry.
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Sean,
At last, a comprehensible reply.
Allow me to buy you a virtual pint of something.
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I'm having serious doubts about the origins of my engine. I haven't had a poke round inside it yet, but it's got a plastic cambelt tensioner, and if it doesn't have hydraulic tappets it's certainly doing a good impersonation of them. I reckon it's a late model 1.8 with the 1.6 manifolds and ancillaries bolted to it. The 1.6 revs to 6,700, the 1.8 doesn't (from memory, 6,250?) and I've been redlining the little car mercilessly since I bought it, just for fun. I thought it sounded a bit harsher than my previous 1600...
Anyway, I've tracked down a proper injected 1600 engine (non-hydraulic), condition unknown but it'll get a full strip down and overhaul before I fit it.
Thanks everyone who responded.
Richard Hall
bangernomics.tripod.com
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RH - I know zilch about old Golfs, but aren't the engines identifiable from their serial numbers?
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I have no recollection of us, ever, fitting a plastic cambelt tension roller.
My knowledgeable friend is on holiday in Boppard, horseriding. I think this question must come to my VERY knowledgeable friend DD.
Is this a Vauxhall-Opel, readily swappable swap, my friend?
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I think this question must come to my VERY knowledgeable friend DD. Is this a Vauxhall-Opel, readily swappable swap, my friend?
To be honest Sean, I haven't the foggiest. I'd be very surprised though.
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But you know everything about Vaux-Opel. I know.
I have read your posts and I bet you work for Adam Opel, but I cannot find you there.
Does anyone know another car that uses a plastic roller in this application, please?
Help us.
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But you know everything about Vaux-Opel. I know.
I'm flattered, but truly no. All that I know is down to experience of owning the things for the past 17 years, and having a couple of mates that have previously worked as Vaux mechanics, oops sorry, technicians.
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>>Does anyone know another car that uses a plastic roller in this application, please?
Yes...several.
M.M
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Oh good.
please list them.
There are many motor engineers here.
Yes, just what you want, motor manufacturing employees from blue-chip motor manufacturers and all that.
Help us, and my friends and I will help you.
Fair deal?
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