Update on 315 exploding engines.

I did my apprenticeship in 1996 and at that time I still don't think there was much torque to yield stuff around then. Since my last post the supplier for the big end bolt has cancelled my order as there are no bolts in the country. I contacted the dealership and they have only some of the bolts I needed at $15 each out of Melbourne. They even wanted $208 for a rear main oil seal (with housing). According to the WIS, the bolts for the mains and big ends can be used if they do not exceed 63.8mm for mains (Big ends I would need to look up again) My bolts are around 63.2mm on average but Im not going to risk using them again. Now I am likely to have my bearings delivered tomorrow and no bolts. The search continues
 

Midwestdrifter

Engineer In Residence
I cannot understand why they fixed something that was not broken with the introduction of torque to yield bolts
Because they are superior in every way. But if you enjoy a head gasket job every 5 years, go for it. The other method is too inconsistent for engines that make 100hp per liter.
 

blackjackmac

New member
There is a place in Taree with mountains of fixings. If you dont find it on Google i will find it for you. Cubic inches is the safe way for performance, with every part built to take the load.
 

blackjackmac

New member
Head bolts yes where there is compression of gasket and aluminium head. I would rather high tensile self locking bolts of same diameter where cap and block are solid. As you point out these engines are delivering sledge hammer blows on either side of intermediate brgs. I dont think bolts designed to yield can take that punishment without going up in diameter.
 
I did manage to get the bolts that I needed but had to go genuine. I got new main cap bolts and conrod bolts which cost me around $180. Although the crank measured OK I had it ground undersize by. 25mm due to pitting on the bearing surfaces. I have since put the engine back together ready to go back into the van. I ended up changing the front crank seal, oil pressure relief valve, rear main, and timing case seals along with the oil cooler seals. The pistons were all replaced which was the due to original issue. Hopefully with only 160k on the original build I should have lots of life left in it yet.
 

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blackjackmac

New member
I bet you miss working on those steam engines
Steam???. that was just coming into vogue after my retirement. I can offer you my understanding of the Carnot principle. My tribe could not come to grips with turning reciprocating motion into rotary motion. that lead us to inventing the wheel.
 

blackjackmac

New member
I did manage to get the bolts that I needed but had to go genuine. I got new main cap bolts and conrod bolts which cost me around $180. Although the crank measured OK I had it ground undersize by. 25mm due to pitting on the bearing surfaces. I have since put the engine back together ready to go back into the van. I ended up changing the front crank seal, oil pressure relief valve, rear main, and timing case seals along with the oil cooler seals. The pistons were all replaced which was the due to original issue. Hopefully with only 160k on the original build I should have lots of life left in it yet.
 

chris02

Member
Hi Eric, just a question.. I have the 2009 sister 315 and thought I was clear on the 646 engine problem, but I was reading another note saying all 646 engines had the problem.. So not sure if I again need to treat the 315 like a baby or its Ok to use the power when needed.. say in sand..

thanks again. Chris
 

Eric Experience

Well-known member
Chris.
I have not heard of any 09 models failing, I think you are OK to drive it in sand, the damage is more likely to show up at full power at very low revs, normal revs are OK. Eric.
 

chris02

Member
ok phew... I'm about to tackle "Googs track" here in Sth Aust - to learn more of the dark art of sand driving. thanks for the reply.
 

owner

Oz '03 316CDI LWB ex-Ambo Patient Transport
I stumbled upon this on my youtube feed. Use google translate if you can't read Russian. The upshot is they have found the same issue as us, crank elasticity under high torque versions eventually spins bearings. They even say it happens in Sprinters around 200km, and cars around 300k.

The Russians use the OM646 to this day in their "Sprinter Classic", so I doubt '09 is any different. They say you can still buy cranks from them (I guess because they are still manufacturing this engine behind the iron curtain). But they note that the crank can damage the block and caps go elliptical, as we have found.

They have tons of engine teardown videos on youtube and go through the problems with each engine type.
 
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Chris.
I have not heard of any 09 models failing, I think you are OK to drive it in sand, the damage is more likely to show up at full power at very low revs, normal revs are OK. Eric.
Hi Eric and friends
A friend is looking at an ex ambo camper conversion to buy.
Dont know the kIlometres, at this stage I just have...

VIN WD8906633281S186864
DATE STAMP 08/07

Am i right this a pariah model?
Ta
Wayne Poulsen
Fremantle
 

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