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results from my VR6 dry / wet compression tests

paceo

By paceo,
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paceo

paceo 22

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as you know my vr6 golf is quiet smokey (blue) from cold and when it reaches temperature its still smoking blue! if i take it for a drive the smoke will clear and when i leave it on idle from a drive the smoke is almost gone, maybe a little bit of blue smoke you can see!

 

here are my results - i put about a teaspoon of oil in it, ive already spoke to vince at stealth racing about this, just want to see your views, compression seems ok, but surely it would be down if i have blue smoke??

 

piston 1 - spark wet with oil - dry test 188, wet test 203

 

piston 2 - mildly moist spark - dry test 188, wet test 203

 

piston 3 - moist spark - dry test 180, wet test 200

 

piston 4 - moist spark - dry test 179, wet test 208

 

piston 5 - moist spark - dry test 170, wet test 195

 

piston 6 - moist spark - dry test 180, wet test 198

 

vr6_zps95cb82ee.jpg

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paceo

paceo 22

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They don't seem bad. Could it not be the valve stem oil seals that are shot?

 

but surely that would cause a loss of compression? 

 

when you start it up from cold and let it idle up to temperature it will kick out blue smoke, not excessive but its there. drive it and it clears.

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Bealieboy

Bealieboy 1,625

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I thought smoke on start up was valve stem oil seals, smoke on overrun is rings, perhaps it could be valve guides? Would They make the engine Smoke when cold and stop as it warms up? Possibly its just cooking off oil from your leaking stem seals. I'm pretty certain they wouldn't affect your compression.

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MK4motionVR6

MK4motionVR6 41

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Hey bud... Sounds like the typical symptoms of worn valve seals. The valve seals get hard over time especially if different oils have been used i.e. Semi synthetic/fully synthetic or mineral oil... Lack of use & long periods of an engine being idle can also contribute to internal engine seals wearing out sooner than that of a well used engine. Eventually the oil in the head seeps it's way down the valve stem & into the cylinders where it'll pool in the seat of the closed valves & drip into the cylinder of the open valves, so on initial start up you'll see blue smoke as the bypassed oil is burning off during combustion. As the oil/engine warms along with the valves, the seals become more pliable thus creating a tighter seal around the valve stems..

During shut down the engine cools, everything contracts & so the oil seeps past the seals again..

Once the valve seals start to perish, it'll only get worse! If you had any trouble with piston rings, you'd notice a considerable difference in compression & the blue smoke would be continuous. As would any problems contributed from a faulty head gasket!!

Mk4motionVR6

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paceo

paceo 22

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Hey bud... Sounds like the typical symptoms of worn valve seals. The valve seals get hard over time especially if different oils have been used i.e. Semi synthetic/fully synthetic or mineral oil... Lack of use & long periods of an engine being idle can also contribute to internal engine seals wearing out sooner than that of a well used engine. Eventually the oil in the head seeps it's way down the valve stem & into the cylinders where it'll pool in the seat of the closed valves & drip into the cylinder of the open valves, so on initial start up you'll see blue smoke as the bypassed oil is burning off during combustion. As the oil/engine warms along with the valves, the seals become more pliable thus creating a tighter seal around the valve stems..

During shut down the engine cools, everything contracts & so the oil seeps past the seals again..

Once the valve seals start to perish, it'll only get worse! If you had any trouble with piston rings, you'd notice a considerable difference in compression & the blue smoke would be continuous. As would any problems contributed from a faulty head gasket!!

Mk4motionVR6

 

if you read above it is continuous from cold up until hot on idle if i leave it. if i then drive it, then leave it on idle you cant see much blue smoke!

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paceo

paceo 22

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I have read above buddy & as I've tried to explain to you.. Your symptoms are that of worn valve stems/seals, because the blue smoke becomes less as the engine warms up!! When cold everything is contracted thus causing oil to bypass the valve seals.... ("Worn valve seals").

Mk4motionVR6

 

if i dont drive the car,  start it from cold and leave it idling untill the fans kick in, it will continuously kick out blue smoke when hot and no matter how long i leave it idling for when hot.

 

its as soon as i drive it and leave it to idle when hot most of the smoke is clear

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MK4motionVR6

MK4motionVR6 41

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Then it's sounds as though the seals are quite badly worn mate... When you take it for a run the higher revolutions of the engine are burning the oil off quicker than its bypassing the seals... And upon idling after a run, it may take quite a while to reappear however, leave it idle long enough & I'm sure it'll reappear!!

Mk4motionVR6

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dox

dox 3

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If the oil stem seals are the originals (20 years old) then they will be hard, cracked and worn.

 

There are three piston rings, compression, oil control and a scraper, you can have good compression and burn oil too if the oil control rings are worn, broken or gummed up with carbon.

 

The compressions are quite good suggesting the bores aren't oval.

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paceo

paceo 22

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Have you run any diagnostics?

Mk4motionVR6

 

not anything else dude, wouldn't mind doing a leak test, well don't trust garages so ideally need someone who is local that has one! The car is not excessive on oil but does use some, when i boot it i dont see clouds of smoke in the rear window!

 

dox - yes its original and she is a J-reg 1992 so an old bird, head has never been off the car by the looks of it! any ideas how to possibly free them up?

Edited by paceo
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MK4motionVR6

MK4motionVR6 41

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To be honest mate if you want a 20 year old car to run perfectly & not use any oil at all, then you may as well get that lump out strip it down & give her some TLC... At the very least get the head off & change the seals.. It just depends on what it's worth to you.

Its most defiantly possible to own an older car with extremely high mileage and have it running like a watch without any major work needed at all, but that would mean it's been used properly & maintained to a good standard throughout its life.. I've had cars with nearly 200k on the clock & run perfectly with hardly any power loss.

People also seem to be under the misapprehension that older cars with low mileage motors are a good thing, that's not necessarily true, especially if it's been sat idle for long periods of time without regular oil changes.

Oil should always be changed irrelevant of mileage as it absorbs moisture & with lack of use, internals components can rust & seals can perish, bearings can seize etc..

I maybe waffling on a bit here, but all of these factors need to be taken into account when buying older cars.

Anyway I hope you get it sorted soon buddy.

Mk4motionVR6

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MK4motionVR6

MK4motionVR6 41

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Can I just point out something here to y'all...

You can't expect to own n run an old motor without there being any problems! Fact of the matter is.. Things that get old wear out & don't work as well as they once did (bit like me lol).

So here's your choices... You can either try patch things up with the hope of keeping it going so it'll last a little longer & put up with things as they are...

Or you can quite your jibber jabber do the job right, get your fecking wallet out & put some money into it, which generally means striping things down & rebuilding stuff properly!!

Yes things can quite easily turn into a money pit, but in my opinion that's what real enthusiasm is all about..

If you can't do it right, don't won't to do it right, then sell up n go buy either a brand new motor with manufactures warranty, or go get something cheap n cheerful that fits the budget..

Of course there is the last option as Dox has stated above; and I quote 'if it drives ok and passes the MOT emissions why bother' unquote!

Mk4motionVR6

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dox

dox 3

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Can I just point out something here to y'all...

You can't expect to own n run an old motor without there being any problems! Fact of the matter is.. Things that get old wear out & don't work as well as they once did (bit like me lol).

So here's your choices... You can either try patch things up with the hope of keeping it going so it'll last a little longer & put up with things as they are...

Or you can quite your jibber jabber do the job right, get your fecking wallet out & put some money into it, which generally means striping things down & rebuilding stuff properly!!

Yes things can quite easily turn into a money pit, but in my opinion that's what real enthusiasm is all about..

If you can't do it right, don't won't to do it right, then sell up n go buy either a brand new motor with manufactures warranty, or go get something cheap n cheerful that fits the budget..

Of course there is the last option as Dox has stated above; and I quote 'if it drives ok and passes the MOT emissions why bother' unquote!

Mk4motionVR6

 

My point being its just using some oil, otherwise the engine appears to be in good working order, you could rebuild it and it still uses oil. VW wont entertain a warranty claim on a new car if its using 1L of oil or less per 1000 miles.

 

When it starts oiling its plugs or the bottom end starts knocking then its decision time.

 

 

Edited by dox
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paceo

paceo 22

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reason is ive got a stage 2 vortec charger to go on the car! no point in putting it on a sickly engine!

 

is just under a teaspoon enough oil? i did put two teaspoons in piston two in the bottom left which sent it up to 260psi, but i thought i put too much oil in!

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