GZE smoke problem

[AEE86]

Have a 4agze conversion in my sprinter, haven't been doing a lot of driving but have recently fixed my major gearbox/diff driveline problems so was keen to get out and about more.

Now I've started driving it I've suddenly got new issues. When I start the car I get clouds of blueish smoke out the exhaust, would seem like oil burning. The smoke decreases a fair bit when the engine warms up to full temp, but there is still evidence of some smoke, particularly when I give it some throttle. If I start up the next day or even a few hours later smoke is back again.

I would normally think things like rings or valve stem seals etc, however when I bought the car it wasn't doing it and had apparently done less than 10,000km after a rebuild of the motor. It should be all fine.

I don't remember it happening in the limited driving I've done, in fact I've only done another 1000km since, and it seems to have only just started happening.

For a bit of background, I run a microtech ECU which may run a little rich at times, but I wouldn't think this would cause blue smoke. I also have a front mount cooler. Have also noticed the plugs look blackish and have become fouled at times.

I don't know if the oil is getting in another way, perhaps its the oil I'm using (Magnatech 10W40) I don't know what oil the original owner used though. Maybe supercharger related? I'm really not keen to pull the head off so would like to try all other possibilities first.

Any Ideas?

Thanks

paul

[superbmobile]

maybe the rings or stem seals could be faulty? that oil seams pretty thin in my opinion maybe its passing through the rings change the oil to something with a thicker viscosity that may help.

[riojin]

if you rev it over 6000rpm it will smoke initially. if its continual then you have a problem. high revs and a gze don't go very well together.

a bit of smoke on start-up is normal also. its usually just because at startup it will run a little rich

[biggo]

do a compression test? may help decide if its the rings (dry then wet test)

[AEE86]

Yeah as I mentioned its not long since it was rebuilt so I wouldn't have thought rings would go yet. But can't hurt to test I suppose.

Will firstly change out the oil to see if that helps.

[terryo]

oil brand/quality is highly unlikely to be your problem
blue smoke is always oil and you need to figure out how its getting into the combustion chamber. It is highly unlikely to be the blower, but you can tell by removing the boost pipe and seeing if its oily inside
If the plugs are black and dry, then thats mixture (too rich), if however they are black and damp/greasy, then thats oil.
Once the engine has been warmed up, give it a good rev and turn the key off whilst it is still revving (about 4000rpm is OK). remove the plugs and look carefully
If you don't have the microtech tuned properly, and it was rich when the engine rebuild was done, then it could have washed out the bores and the rings have not bedded in properly. This will definiently cause your problem.
The quality of the rebuild will also play a role, valve stem polished??, new stem seals fitted??, type of hone finish , type of rings etc etc.
once you do the tests, let me know and I can then look at it for you if you want. it generally easy to work out your problem. . PM or email is easiest

[DavisJD]

<div class='quotetop'>QUOTE </div>
blue smoke is always oil and you need to figure out how its getting into the combustion chamber. It is highly unlikely to be the blower, but you can tell by removing the boost pipe and seeing if its oily inside[/b]

I'll save you pulling off your supercharger outlet and tell you that it will be covered in an oily like substance, don't know what it is, but all GZE's seem to get it. There a filthy little motor!

[Gunner]

pull ur cooler off and clean the oil out of it

[AEE86]

Thanks for all the info, all makes sense except would this account for it starting all of sudden? I would have thought if the rings were failing it would have been a gradual process?

I get literally CLOUDS of smoke on startup, then after 15 mins of driving its only mildly noticeable. A few days earlier it was ok.

[biggo]

obviosly you had oil leaking in to the CC from somewhere, which so happens to still be doing it.

its a trial process, be prepared to remove/refit alot of things before you find the problem. And make sure you are certian its the prbloem too :P

Oh yair, cooler pipes will be oily hehe