Outer Limits 4x4 Board

OK I just finished rebuilding my 3L and I have a couple of problems and was wondering if any body here could tell me :
A if you can get oversize oil seals for the crank as the brand new ones I put in are leaking a fair bit.
B how long should it take for new rings to bed in? as my exhaust is a little smokey and it smells of burnt oil. I think this is why the seals are leaking so bad to because there seems to be blow by past the rings pressurising the crankcase. This has settled down a bit but it still is evedent when you remove the breather there is a fair amount of gas comin out of there.

Cheers Pete

Mate,
I think you should have at the very least put sleeves on the crank where the seals run, or put the seals in not so far, so they run on an unmarked part of the crank.
Sounds like a wear ring on the crank sealing surface where the seal runs is the problem. Did you lenish it with some scotchbrite pad to take the shine off it??, very lightly only to clean up the surface, dont put scratches in it.

Re bedding in, some say its a dark art, however to bed in rings, a run at open throttle thru the gears, without going over 4000rpm in the petrol race cars used to do the trick. however since its a diesel, after its first 10km run, it should be well and truly seated in the ring dept.
The rest of the engine however is going to take longer to "run in".
Dont stay at a constant rpm/ speed for extended periods, avoid high revs and labouring the engine at low rpm. Im sure others will happily chime in re breaking in an engine.

Re the blow by.
you did get the cyls honed/ machined for square, and round?
you did get matching pistons and rings to suit any oversize that was obtained in the machining?
You did put the ring gaps in the correct spot on the pistons ?

not trying to ask stupid questions, but there shouldnt be any real blowby in a new motor.

Smoke out the exhaust for a while is ok, say the first 10 min of running just depends on how much oil you put in the cyls and ring lands when assembling.

how many hrs/ kms have you put on this motor so far??

Trains

Hey trains,
yeah had the crank linished and put the seals in further then they where originally. I think I will have to drop the crank out and have the it sleeved
a friend suggested trying to fit a second set of seal but I am unsure if they will fit?

The engine has done 1500 km since rebuild already

The cylinders where bored and honed to match the pistons and yeah the ring gaps where in the correct positions according to the manual.

did put a fair amount of grease on the bores when I put the pistons in as per the instructions with engine rebuild kit I got. I would have thought that this should be gone by now but ??

Pete

I understood that you are meant to labour the engine at low revs while running it in. also for a pterol you should use run in oil and methods for first 1000K's then change oil.
-Calvin

not sure I just drove it normally I did do an oil change after 1000km but never uses any "special" run in oil just penrite 15w/40

hokey wrote:I understood that you are meant to labour the engine at low revs while running it in. also for a pterol you should use run in oil and methods for first 1000K's then change oil.
-Calvin

nah mate, dont labour it under low revs, specially if its a petrol, you will glaze up the bore. You can kill it with kindness.

Spud got it pretty much right.
General city driving, ie start stop, run thu the gears under light to med load, with the occasional venture to full throttle and a few more revs each time, is pretty much the go to run in an engine.

Some use run in oil, others dont, some use cheaper oils for the initial run in phase, some use expensive stuff, and change it at 500km or 1000kms.

Dont labour, or thrash it, and your well on your way.

Hmm, if you pushed the seals in further, that sounds a little strange.
They usually seat home when put in the correct position, ie where the seals were last.
Ive Not been able to push them in further.
Did you put rubber grease, or some oil on them, and inside the dust seal lip, and seal, there is a small valley there in the seal.
if you put them in dry, they could fail rather quickly.

Sorry to ask the question re the ring gaps, but ive come across engines that will suddenly start to use oil, and the reason is that the rings have moved, and the holes have lined up for a short period of time. They eventually moved so they didnt line up, and problem stopped.
Go figure.

re sleeving it, a speedy sleeve can be installed without removing the crank from the block. Both front and rear.

Re grease on the bores, ive never used grease before, just oil on the rings when installing them, and a good wipe of the bore with oil, then put the piston in.
hopefully others who have successfully used grease on the bores will add something to that. It is not what I would have done myself, thats all.
However im happy to learn new ways of doing things.

Spud76 wrote:Hey trains,
yeah had the crank linished and put the seals in further then they where originally. I think I will have to drop the crank out and have the it sleeved
a friend suggested trying to fit a second set of seal but I am unsure if they will fit?

The engine has done 1500 km since rebuild already

The cylinders where bored and honed to match the pistons and yeah the ring gaps where in the correct positions according to the manual.

did put a fair amount of grease on the bores when I put the pistons in as per the instructions with engine rebuild kit I got. I would have thought that this should be gone by now but ??

Pete

I never use grease in the rings +bore, the grease gets in the hone crosshatch and the rings can't bed in. I use assebly lube in the bearings only. I use mineral oil to run the engine in, put it under load for short periods of time and vary the engine speed all the time but try to keep at lower revs.

I just got a HM Gem remanufactured engine fitted to my Landcruiser and the run in instructions are to not be too easy but not too hard on it. Try and avoid prolonged periods of idle and highway running.
I've got to get the oil changed after 800km's and I can't run it on LPG until I've done 1000km's. It seems to be going pretty good so far. It's certainly got more grunt than the old donk had.

Thanks for the advice guys. It is pretty well run in now and I didn't thrash it or make it labour and i did vary the speeds but never really pushed it over 3000 at all in the first 1000 nor let it labor. still leakin but will have to look at sleeving the crank now i guess.
bugger!!!!
cheers pete