engine and drivetrain Loud and smoky M10

[bltom]

Hello everyone

 

so the thing is I have put my 02 back on ther road after a full restoration and after one month/aprox. 2000km later there have been some issues that popped out.

 

Despite engine had a full rebuild with all new bearings, been honed, new piston rings, new valve steam seals, im having a major issue with smoke coming out of exhaust, its blue so obviously its burning oil, but where? Most noticeable is when idling and when releasing a gas pedal (in that 2000km period he took 2 litres of oil)....  Im running out of ideas where to start fixing that problem

 

Some say use thicker oil (currently im running Castrol 10W-40 part synthetic), others says ignition/distributor have something to do with this...my major fear is that its actually something wrong inside the engine :/ 

And the other big problem is noise coming out of the engine after it comes to working temperature, valves has been set to 0.15mm clearance and the engine is running beautifully when its cold, but after a while it gets this noise ( trrrrrrr sound) only when Im on throttle.
I heard M10 was known for being extremely sensitive about worn out rocker arms, and mine are still original. Would you guess this is the reason for noise or there might be something else??

I appreciate all the help  thanks

[tups]

10W40 is too thin an oil - the correct oil to use is 20W50. "Some" are right

 

[LimeySteve]

Oil control rings are my guess, does it smoke on deceleration too ?if so I'd check the rings, my 1st build did the same , engine guy rebuilt with different oil scraper rings , problem gone. 

[TobyB]

.15mm is less than .006"- that's awfully tight.  Conventionally, we say .007"- .008".

 

Usually, tho, that would make it quieter, not louder...

 

As to oil, were your pistons measured carefully?  The M10 seems to wear pistons- I find few in used engines that are reusable..

 

Beyond that, thicker oil, and drive it hard.

 

t

 

[Conserv]

It sounds as if you have more going on than simply an oil issue but Korman believes you should not use a synthetic oil during the break-in period or even during the first 5,000-10,000 miles: it's lubricating properties are so good that it will excessively prolong or even prevent break-in from occurring.  They put in a watery straight-weight oil (20W?) for the first 2,000 miles.

 

Steve

 

[bltom]

thanks for answers guys  i will definitely try 20w50 oil and we will se how it goes from there.  before that i will also measure compression if there are maybe some leaks in the cylinder..does anyone have a info what the compression should be on 2002?

 

even if this oil change is gonna partially solve smoking problem there is still that strange sound coming out of the engine,   @TobyB yeah is should be quieter after setting the clearance ..it is until its cold, but the 0.15mmm measurement was found in service manual so thats why i went for this at the beginning 

[KFunk]

Has it been driven hard at all, or just babied for the first 2000km?

 

the rings need seated well, and I'm of the opinion that it needs to be driven hard right after the rebuild to put some pressure on them and seat them well.  Get on the gas hard and engine brake a few times, if you haven't already.  I ran the piss out of my engine right after the rebuild, immediately after getting to operating temp.  Never any oil usage from it, and no sign of smoke.

 

however, yours does sound real bad like some rings weren't installed right.  Were the gaps staggered like they should be, instead of all lined up?

Edited May 9, 2016 by KFunk

[OriginalOwner]

Le was telling me just the other day that Ring Quality is a possible culprit.  HIs machine shop guy has seen "kwality" problems with rings, and believes that they aren't as well made as in the "old days."

 

Cheers,

 

Carl

 

[bltom]

@KFunk it wasnt driven to the maximum but it wasnt babied as well..twisty roads aprox. 400km (250 miles) per weekend for the last three weekends, average speed around 90-110 km/h (50-70 miles per hour) at 3000-4000 rpm

 

New piston rings are from Goetze..
As said all the noise is gone in the same second i remove my foot from the gas pedal when driving...also at this time smoke from the exhaust is usually  at maximum

Edited May 9, 2016 by bltom

[Preyupy]

Any chance they used Standard size rings on an overbored cylinder (they would fit on the pistons but would not seal worth a damn.  Did anyone check the ring end gap (I know you said they were installed at 180 deg from each other)?  Sounds like a ring problem.  The noise might be a loose timing or oil pump chain.  There are many possibilities it is very hard to diagnose without actually being there to hear what is going on. 

[bltom]

yeah I have considered that option of to small rings as well...eventually if nothing will work i can try replacing them..

 

Ring gap was definitely checked, its true i typed 180 degrees but i wasn't sure i said it right haha before i checked it..the were done according to shop service manual  as well as goetze ring instructions.

 

I do my best to record that sound today

[bltom]

so i changed the oil today to mineral 20w-50..so far so good, just have to get one of my friends to drive behind me and see how it goes.

 

regarding engine noise, this is the video that was shoot today, engine at this point was relatively cold and you can already hear the sound...sounds like an old diesel :/ 
 

 

Edited May 10, 2016 by bltom

[TobyB]

Buy a stethoscope.

To me, that sounds ugly, but I can't

tell where it's coming from.

 

It could be rod knock, but it could very well be a manifold gasket leak

fwiw

t

[NickVyse]

well that doesn't sound good - surely your first point of call is the engine builder? I had an engine rebuilt years ago and chose the cheapest shop based on my Fathers advice. Learnt two lessons - Dads aren't always right and not all engine rebuilds are equal. The cowboys had thrown in different sized bottom end shells - sounded a lot worse than yours.

Edited May 11, 2016 by NickVyse

[vinntagejoe]

Hey bltom (from Europe) that's a bitchin stance in your profile pic!

 

(by any chance, are you lucky enough to be going to the CL final in Basel? going to any Euro games this summer?)