blue smoke after engine rebuild, advice please.

[Quattro Dan.]

I have recently rebuilt my ABY engine, honed, new rings, bearings, uprated rods, scimmed vac tested and pressure tested head. The only thing i did not do on the head was vale guides and valve stem oil seals.

I have run the engine in but i am getting blue smoke on over run, tickover and hot starting. The car still runs well. I have since replaced the VSOS in situ and the smoke went away for approx 100 miles but is now back just as bad!

I have clean PCV pipes and there is only minimal oil in the boost pipes, turbo has no oil either side of it.

Is the blue smoke just down to worn valve guides? help and advice greatly appreciated.

Thanks in advance, Dan.

[Tonks4x4]

What is the compression figures just out of interest?

And what grade of oil are you using?

[Quattro Dan.]

What is the compression figures just out of interest?

And what grade of oil are you using?

10w 40 quantum oil.

[europeanme]

I do remember Ian (Bazburn's car) smoking a little and that turned out to be a loose hose but I cannot for the life of me remember which one..

[Quattro Dan.]

What is the compression figures just out of interest?

And what grade of oil are you using?

A cold dry compression test all cyls were about 120 psi, roughly 700 miles after rebuild.

[docspeedtriple]

Smoke

I had the same problem on my 3b I also honed and fitted new rings and bearings but I also had. To fit 10 new guides on exhaust side and 20 valve oil seals no more nasty blue stuff.

[pasbogdan]

I have recently rebuilt my ABY engine, honed, new rings, bearings, uprated rods, scimmed vac tested and pressure tested head. The only thing i did not do on the head was vale guides and valve stem oil seals.

I have run the engine in but i am getting blue smoke on over run, tickover and hot starting. The car still runs well. I have since replaced the VSOS in situ and the smoke went away for approx 100 miles but is now back just as bad!

I have clean PCV pipes and there is only minimal oil in the boost pipes, turbo has no oil either side of it.

Is the blue smoke just down to worn valve guides? help and advice greatly appreciated.

Thanks in advance, Dan.

Valve seals do leak on over run.If the guides were fine,you could change seals with head on the car.If guides were not cecked do not change seals without guides.They will wear soon.Not good to rebuild an engine and not replace old valve seals.

[Tonks4x4]

He has already replaced the valve stem oil seals.

I take it the smoke clears when under load? so not the turbo.

It has got to be guides if everything else checks out ok.

[JP]

Yep symptons point at exhaust guides intakes rarely wear on these engines.

[Thuppu]

I had also a lot of blue smoke and high oil consumption soon after rebuild. Seems that the bores are glazed for some reason and needs a re-hone.

[Carfreak]

Have the same problem after a full wot run.. But i think mine sucked in oil threw the breather in the valve cover to turbo intake since I have alot of oil there.. Mounted a catch tank that vents to the atmosphere - well see how it works. Made a comp test and got 11bar at all 5. I will also do a leakdown test!

All my other crank breather things are new but when is it nessecary to upgrade to oil seperator and catch tank ? I´m running 2bar of boost with a Gt35 and regular pump gas..

[Rusty]

Run the breather to atmosphere and see if it still does it.

[Quattro Dan.]

UPDATE. Stripped the head off and i have driven out the old valve guides and pressed in 20 new Febi guides. The old exhaust guides had quite a bit of wear in them.

I previously stated i had cleaned the pcv pipes, must have missed one as the one with the copper gause was totally blocked with crusty old oil. I bet this was the problem or could the worn guides have contributed to the build up? Either way it should be cured now.

[Quattro Dan.]

Just got to lap the valves in, any advice on this is appreciated as i have never done it before, can i use the sucker tool on my cordless drill? also what paste should i use?

Cheers, Dan.

[Christophski]

How do you do the guides as i have been told its a case of heating anc cooling and lots of money to get it done...?