Oil Usage!

[G60 Bob 0]

Ive got a '92 G60 that uses about half a litre of oil every 4 weeks or so. There are no leaks and i dont notice toomuch in the way of blue smoke from the exhaust and never go above 3000 rpm until the oil temp gets above 90 degrees. I do however have a short commute to work about 3-4 miles so the car doesnt even really warm up by the time i get there.

I know this means i could probably do with getting the oil valve stem seals done (how much should this cost?), could it be anything else? Does this usage seem very bad or is it just the nature of the beast?

 

Thanks in advance guys

 

R

[stevemac 0]

Your car use water as well ??

[G60 Bob 0]

No not at all, and its only done 89k from new!! Everything else is fine eg power, drivability, no funny noises etc

 

Any ideas?

[stevemac 0]

Very likely to be valve oil seals which have gone brittle with age - mine need replacing as well :(

[G60 Bob 0]

thanks for your replies Steve.

Whats involved in replacing the seals and would this be a good time to do anything else while it was in the workshop?

I know it will vary widely from place to place but do you have a ball park figure of what it would cost?

[kvwloon 0]

Very likely to be valve oil seals which have gone brittle with age - mine need replacing as well :(

 

Reckon mine are going the same way now (140+ K), but not sure if I can trust any garages round here to do it properly :roll:

[coolrado 0]

i dont think the head needs to come off but the the camshaft and hydraulic tappets do need to be removed to change the stem seals(might be worth getting the tappets replaced at the same time) also i have heard some people have had problems with some oils going through the engine like a dose of salts. what oil are you using?

[Kevin Bacon 5]

89K is a bit low for needing guides on the 8V? Although it's approaching the 100K milestone where most VW heads of that era would benefit from a head rebuild. My VR's needed doing at 93K, well, not *needed* as such but having done them the oil consumption has reduced drastically, so there was obviously some slack in the guides.

 

As mentioned already it is possible to replace the seals without lifting the head but that merely defers the inevitable to a later date as the slack guides cause the valve stems to eat your nice new seals away.

The few hours labour involved doing just the seals would be better put towards a proper rebuild, which doesn't cost the earth for an 8V head.

 

None of the Corrado engines like overly thin oil either, so try a flush and refill with Quantum silver first.

[Roger Blassberg 0]

A sure sign of valve stem oil seal failure is blue smoke immediately after a period of running down hill on a closed throttle - the high manifold depression sucks the oil past the seals to the inlet valves and into the cylinder. Then it burns off once you go back on the power.

 

I would have thought that the valve springs need to come off to get at the seals which are hidden inside them, in which case the head needs to come off so that the springs can be compressed to release the collets and caps. That's a good opportunity to change the springs.

 

Also, if the seals have been leaking, there is bound to be lots of carbon deposited on the backs of the valves and this can be scraped off at the same time.

 

Check the guides for lateral movement and replace if they are too far gone. Regrind the valve seats if they are in reasonable condition, recut them if they are either badly pitted or if the guides have been renewed. Inevitably, original valve seats will not be absolutely concentric with the new guides. The exhaust valves will leak and burn out if this is not done because they do not get a chance to give up their heat to the valve seat.

 

This based on my experience with other vehicles - maybe the VW 4 cylinder is different.

 

Best wishes

 

RB

[Kevin Bacon 5]

Yeah you can do the seals without lifting the head.... you can get a special tool that pushes the valve caps down without having to clamp to the valve face from underneath. Then you put compressed air in the cylinder which holds the valves up whilst you slide new seals over the valve stems.

 

This is an old trick done by garages to shift a car that's burning oil, but still has relatively good power and running smoothness.

[Roger Blassberg 0]

I can't believe that the proud artisans of the garage trade would even consider such a thing.......

 

Thanks again Kev,

 

Best wishes

 

RB

[coolrado 0]

ive even heard of garages moving the pistons to tdc and resting each valve on top of the piston and changing four seals at a time instead of using a compressor to hold the valves up.

but they still used the special tool to remove the valve collets and spring

[G60 Bob 0]

been using Synta Silver since i got the car about 6000 miles ago and was about to change the oil but now i havent got enough left as i keep having to top the level up every couple of weeks!

 

I dont mind doing this as the oil is cheap enough but wanted to make sure that i wasnt doing any further damage.

 

Can anyone recommend any specialists in Northern Ireland or Belfast to be exact?

[stevemac 0]

ive even heard of garages moving the pistons to tdc and resting each valve on top of the piston

:oops: :oops:

 

 

Far better, as Kev says, to remove the head & do a proper rebuild. Should be good for another 100k then 8)