15 replies to this topic

[Jazz9]

Hello,

I have a weird one.

My vr4 does about 50-60kms a day. I don't give it much stick ( only 9-10psi currently ) while my secondary car is off the road.

I cruise for about 10 kms from work and then when I give it a WOT 3rd gear pull there is smokes enough to see it in the rear view mirror.

If I slow down and do the same pull again - it doesn't smoke. It doesn't do it again for the rest of the trip ( out of town boosting )

i had some oil in the intake so I put inlarged breather on the rocker and 12mm id line to a catch can. It got rid of the mess in the intake. Left the PCV stock.

The turbo ( gt pumps 20G ) is less then 10,000kms old and the motor is less then 20,000kms old,

I guess there is oil pooling in the intake somewhere - PCV maybe? and on hard accel it goes through the motor.

I have repeated this for about 3 days in a row and its the same each day.

Glen

Edited by Jazz9, 09 November 2012 - 01:58 PM.

[jack be nimble]

dry and wet compression test?

[Jazz9]

i'll check Sunday. U reckon rings or valves?

[jack be nimble]

rings. with 20000k on it, it should have bedded in by now. But i dont know much about leaky turbos.

but the compression test will give you a baseline, and a state of the engine.

what was done to the bottom end? oversize pistons and bore, or std pistons and hone with new rings?

[Jazz9]

20 thou over with wiseco forged pistons, eagle rods. cometic, arp studs and bc 272's.

It is a bit noisy on startup - gets better when warm, I suspect a leaky exhaust gasket.

i'll swap the pcv over as well on Sunday.

[Jazz9]

swapped the PCV over and the compression test came back good ( less then 10 psi variance and hot - wet was 165 1-2-3 and 155-160 number 4. dry was about 7-10psi less)

still no good

Did a long run today and found that it only smokes when i've been idling for a while and then take off and boot it. But it doesn't smoke while idling.

Don't valve stem leaks smoke at cold start? I don't get that at all! Only when hot idling then booting it.

Ideas?

Edited by Jazz9, 20 November 2012 - 01:49 PM.

[jack be nimble]

Sounding like stem seals to me.

Good on you for doing the wet and dry test.
Cold oil may be too thick to be drawn into engine.

Does it burn oil? What about water?

[Rockabilly]

+1^ Typical the hotest #4 ext valve guides have slop & maybe more ext guides.
Plus maybe the valve stems weren't cleaned further for the 272s travel.
Cheers !

[Jazz9]

im going to change to 15-50 from 10-40 and see how it goes. I drove 185 kms today and then idled for 5 min and boosted away with no issues .... sooooo strange!!!

I'll order some stem seals. I'll make a leakdown tester too.

Reckon that pouring out smoke while beating a new SS would make the SS driver a bit sad?

Glen

[jack be nimble]

They are on eBay for less than $100, but I made mine ages ago, pretty easy to do

[Jazz9]

you wouldn't want to give me a hand swapping them over? I've never done stem seals before. Happy to throw in some coin or beer !

[jack be nimble]

im flat out between now and xmas.
I dont have the tool to compress the valves while the head is on either. I would have to custom make one.

sorry

[Jazz9]

After a lot of stuffing around today, I reckon its prob valve guides too. There is more blow by at idle then when free reving the motor. The blow by is very even - not like when it is a piston ring.

I'm going to pull the head and rebuild it.

Reckon I should replace valves, guides and stem seals? Anything else while there?

Glen

[jack be nimble]

compression test dry and wet before you pull the head. this will give you a general indication of engine health.

i personally would chuck some stem seals on it first and see how it goes with them. stuff pulling the head if you dont have too.

if you do pull head, put some kero in the ports to show the valves that are leaking. relap the valves that leak till they seal.

[jack be nimble]

you wouldn't want to give me a hand swapping them over? I've never done stem seals before. Happy to throw in some coin or beer !

you have a PM...

[Jazz9]

yeah - I found somthing else this morning. I pulled the spark plug and there is oil leaking from the rocker cover down around the spark plugs. I noticed it when I did the compression test and I thought it was from some previous work - obviously not!

I'll pull the rocker cover tonight and have a look at the seals.

Glen