51 replies to this topic

[OGGMAN]

I think you're chasing your tail with the compression test. The pistons have oil control rings and compression rings, so it is theoretically possible the oil control rings are shot, allowing oil up the bores, while the compression rings are doing their job.

Another thought, there must be some compression, as the car works, so unless you have a benchmark engine, you will end up with four readings that don't mean a great deal.

If you are burning oil it has to be from the bores or the valve seals (assuming N/A). It is rare for a specific 'fault' to develop, it is usually general mileage related wear. Not what you wanted to hear, but I would save your money on the comp tester.

Bearing in mind that the car only smokes just before the redline and at no other time would I be likely to cause loads more damage if I just continue to drive the car for the next few months and keep the revs under 5500 rpm??

The car would still work with a shot piston ring, so that shouldnt deter you from testing, albeit not very efficiently or smoothly.

For a simple £12 on a guage to test and eliminate any possible reasons for the problem, it isnt much. Do the test, get the results and sell the guage again on ebay.

[NA Jimbo]

I'm concerned as to whether I can drive it like it is and keep the revs under 5500 or will this cause more damage like scoring a cylinder?

Edited by NA Jimbo, 22 July 2009 - 12:29 PM.

[techieboy]

If it's damaged, the damage is already done. Keep an eye on the oil level and drive it. I've just done a trackday with whatever is wrong with my rebuilt engine and had it up at the redline on numerous occasions with no apparent effect- other than the already increased oil consumption.

[John Faulkner]

If it's damaged, the damage is already done. Keep an eye on the oil level and drive it. I've just done a trackday with whatever is wrong with my rebuilt engine and had it up at the redline on numerous occasions with no apparent effect- other than the already increased oil consumption.

Not sure that's the best advice i've ever heard TBH, especially as the problem is still unknown.

[NA Jimbo]

Compression tester had now been ordered. In the meantime I've tried a couple more tests to no avail as it's still smoking. I've blanked the egr off and disconnected the breather and been for a spin with kitchen towel taped over the breather to see if anything is being blown out but the paper stayed pretty clean. I am now thinking that it must be piston rings but am confused as to how they can suddenly have deteriorated at 50k right after a service. I'm gonna tackle this myself and am trying to mentally prepare myself for any issues but am hoping to just change the rings with the engine in situ (can't face taking the clam off again after engine swap). Is there a high likelihood that I'll be met with further problems such as cylinders needing reboring or is it common to just change the rings and it be that simple?

[slindborg]

rehone as a minimum

[NA Jimbo]

rehone as a minimum

i've had a quick read up on this, block can stay in car so easy enough. What is the likelihood of the bores not being scored? Is it common to just change the rings with no further damage?

[theolodian]

rehone as a minimum

i've had a quick read up on this, block can stay in car so easy enough. What is the likelihood of the bores not being scored? Is it common to just change the rings with no further damage?

If it is just burning oil and not low on compression then a rehone should be enough. The only way you are going to know for sure is a scope or pulling the head.

If you have somewhere to store it I highly suggest taking the clam off for major engine work.

[Zoobeef]

Compression tester had now been ordered. In the meantime I've tried a couple more tests to no avail as it's still smoking. I've blanked the egr off and disconnected the breather and been for a spin with kitchen towel taped over the breather to see if anything is being blown out but the paper stayed pretty clean. I am now thinking that it must be piston rings but am confused as to how they can suddenly have deteriorated at 50k right after a service.

I'm gonna tackle this myself and am trying to mentally prepare myself for any issues but am hoping to just change the rings with the engine in situ (can't face taking the clam off again after engine swap).
Is there a high likelihood that I'll be met with further problems such as cylinders needing reboring or is it common to just change the rings and it be that simple?

Are you talking about the breather between the rocker cover and the inlet pipe? im working on a 2.2 vectra at the min thats smoking and i think the oils getting in from this, excessivly for some reason. If you disconnected it then put the kitchen towel over the hole your losing the vacuum of the inlet pipe to suck the oil through. Have you looked in your inlet manifold to see how oily it is in there?

[NA Jimbo]

Compression tester had now been ordered. In the meantime I've tried a couple more tests to no avail as it's still smoking. I've blanked the egr off and disconnected the breather and been for a spin with kitchen towel taped over the breather to see if anything is being blown out but the paper stayed pretty clean. I am now thinking that it must be piston rings but am confused as to how they can suddenly have deteriorated at 50k right after a service.

I'm gonna tackle this myself and am trying to mentally prepare myself for any issues but am hoping to just change the rings with the engine in situ (can't face taking the clam off again after engine swap).
Is there a high likelihood that I'll be met with further problems such as cylinders needing reboring or is it common to just change the rings and it be that simple?

Are you talking about the breather between the rocker cover and the inlet pipe? im working on a 2.2 vectra at the min thats smoking and i think the oils getting in from this, excessivly for some reason. If you disconnected it then put the kitchen towel over the hole your losing the vacuum of the inlet pipe to suck the oil through. Have you looked in your inlet manifold to see how oily it is in there?

yeah the breather from the rocker cover. I cleaned the manifold out with petrol the other day (it seemed quite wet and gunky) and there wasn't really anything in the inlet pipe. I think I saw your post last week, was this the vectra you thought might need new stem seals?
The problem was that the car still smoked on a long drive out with the breather detached.

[theolodian]

Compression tester had now been ordered. In the meantime I've tried a couple more tests to no avail as it's still smoking. I've blanked the egr off and disconnected the breather and been for a spin with kitchen towel taped over the breather to see if anything is being blown out but the paper stayed pretty clean. I am now thinking that it must be piston rings but am confused as to how they can suddenly have deteriorated at 50k right after a service.

I'm gonna tackle this myself and am trying to mentally prepare myself for any issues but am hoping to just change the rings with the engine in situ (can't face taking the clam off again after engine swap).
Is there a high likelihood that I'll be met with further problems such as cylinders needing reboring or is it common to just change the rings and it be that simple?

Are you talking about the breather between the rocker cover and the inlet pipe? im working on a 2.2 vectra at the min thats smoking and i think the oils getting in from this, excessivly for some reason. If you disconnected it then put the kitchen towel over the hole your losing the vacuum of the inlet pipe to suck the oil through. Have you looked in your inlet manifold to see how oily it is in there?

I also vote with both hands that you should absolutely rule out other possibilities before deciding that it is rings or even valve seals.

[Zoobeef]

Yeah did the stem seals yesterday and turned out it wasnt them, then noticed the breather pipe was oily and the inlet manifold had little pools of oil in it. My next thort is that the crank case breather is blocked so ive got higher pressure which is pushing more stuff through the rocker breather. Can anyone comfirm that the crank breather runs into the inlet manifold? Sorry for highjacking your thread

[NA Jimbo]

Theo, I'm not sure if you posted at the same time as my last post. I'm really struggling to find ways to isolate the cause beyond ruling out the egr and the breather pipe is there any other way I can narrow the cause down?

[davep24]

EGR is not connected with the oil circuit so that can be rules out. Have you checked the crankcase breather between inlet ports 2 and 3 and on th inlet manifold, There should be a small brass/copper orifice plate about the size of your thumb

Edited by davep24, 23 July 2009 - 08:47 PM.

[NA Jimbo]

EGR is not connected with the oil circuit so that can be rules out.

Have you checked the crankcase breather between inlet ports 2 and 3 and on th inlet manifold, There should be a small brass/copper orifice plate about the size of your thumb

I actually changed the inlet manifold yesterday as I cracked the brake servo pipe off mine whilst I was messing

edit: what I mean by this is that the problem has persisted with two manifolds

Edited by NA Jimbo, 23 July 2009 - 08:53 PM.

[theolodian]

Theo, I'm not sure if you posted at the same time as my last post. I'm really struggling to find ways to isolate the cause beyond ruling out the egr and the breather pipe is there any other way I can narrow the cause down?

I'm afraid that I'm not familiar with the details of these engines or I would be giving you more specific advice. Even if the engine had over 100K miles I wouldn't jump to think it was the rings or the valve seals. Breather systems on the other hand are always suspect. I've seen engines where a rubber hose goes soft and droops and it is enough to cause bad oil smoke, even though the hose has no leaks in it. I doubt that the specifics are relevant to your case, it is just an example of how weird breather problems can be.

[NA Jimbo]

I'm now more confused with this than before. If the compression test doesn't show anything then I'm stumped. I've bought some more oil to top up with if I need it. I've gone for 5w50 to see if this helps, should this viscosity be safe to use?

[slindborg]

I'm now more confused with this than before. If the compression test doesn't show anything then I'm stumped. I've bought some more oil to top up with if I need it. I've gone for 5w50 to see if this helps, should this viscosity be safe to use?

ohh where did you get 5/50 from? (please dont say dopeyoils)

[NA Jimbo]

I'm now more confused with this than before. If the compression test doesn't show anything then I'm stumped. I've bought some more oil to top up with if I need it. I've gone for 5w50 to see if this helps, should this viscosity be safe to use?

ohh where did you get 5/50 from? (please dont say dopeyoils)

it's halfords own trackday oil. Is this gonna be ok with oil jet etc?

[Zoobeef]

Should be no thicker than any other oil thats 5w, it'll just stay thicker when it warms up