Rebuild or Long Block?

[67_Valiant]

I bought my truck at auction with about 76k on it (salvage = no warranty). Since it was salvaged for an engine fire, I repaired as needed (intake manifold, wire harness, fuel injection return lines, and one cylinder head due to breaking off a glow plug) and got it running. It is totally stock (I live in California), and passed safety inspections, brake and lamp, smog, etc with no problems.

It was running great, and I had about 2k miles on it (since repairs) when suddenly it lost oil pressure on a drive with my wife. I had it towed home, and upon pulling the pan, found metal shavings. I am convinced the main bearings are done, but hoping i shut it down quickly enough to minimize the damage.

I really like the truck and have decided to keep it, but I can't decide if I should tear down the engine and rebuild it (where I have complete control of the build), or opt for a factory long block. The cost to do it myself is about 2k cheaper.

I'd love to hear from anyone who has done either.

 

[Tremper126]

If you can find a rebuild master kit please share! I enjoy having spare motors laying around lol the only thing I would worry is if the crank is damaged that would add some cost to the rebuild as I doubt new bearings would resolve the potential scarring on the crank.

 

[TC Diesel]

I have never seen or heard of the crank survive the puking....its likely the cam bearings and other rotating surfaces did not survive either. Once that worthless by-pass opened when the filter became plugged the debris was pump thru-out the engine.

 

[67_Valiant]

That makes sense TC.

I will be pulling the engine this weekend and start tearing it down. I have not been able to find a master rebuild kit from Mopar, but I will keep looking. With a lot of these trucks starting to come out of warranty now, you'd think someone would start putting a master kit together...

 

[TC Diesel]

No, the engine is manufactured in Cento Italy, With all the reliability problems connected to QC and the facts theirs's only about 160K made from 2014-19 Plus the AEM extension it just not worth the hassle to equal $$$$

 

[67_Valiant]

Just following up on this. The engine is apart, and the #2 and 3 mains are spun. These cranks have a very small service range (2.9110"-2.9117"- that's less than 0.001"), so spun bearings are definitely going ruin it unless it's caught and shut off immediately. Mine measured 2.9092" on the #3 main, so it's toast. The rest of the engine looked fine with very little shrapnel making it outside the pan.

I'm used to cranks that can be ground up to 0.02" undersize, so <0.001" service range makes it seem like this piece is a disposable item, or designed to be rebuilt at a certain service interval.

Since a new crank is over $1k, and it would probably also require a line bore to clean up the block, it's going to make more sense to buy a new long block and replace it. If I find a burned engine with a good crank for cheap, I might rebuild the old one as a backup though.

I have tons of pictures of the disassembly process including removing the engine if anyone needs it for reference...

 

[billetecodiesel]

i know im a little late to the post but im actually in the process of rebuilding my engine aswell, i snapped my #5 connecting rod in half from boost. i sourced billet rods from Wagler Diesel and decided to have billet pistons and crank made from a company in missouri. all bearings are from king. block is currently at the machine shop. so now i wait for the machine shop to see how bad the damage is and how far i can bore. now this isnt not cheap any means but i plan on keeping the truck and didnt want another crate with junk rotating assembly that wont take the power im putting to it. oh as far as prices go Rods $1,800, Pistons $2,500, and crankshaft was $3,000. im shooting for 500-550 range power wise so thats my reasoning behind the overbuild and decison to have billet parts made. hows your build coming or how did it go 67_Valiant?

 

[67_Valiant]

Hey @billetecodiesel - I ended up having to junk that engine. Several machine shops told me they could not save it once the bearings spun.

I have since rebuilt 3 other engines, but have been unable to find any oversized pistons (unless I ordered custom). I talked to Mahle and Hastings, and both told me the same thing- they typically wait 8-10 years after a new diesel engine has released before they will make a decision to make pistons for it which has to do with the cost/benefit of creating a new casting, how many pistons they think they can sell, etc. Mahle said I could order custom forged pistons; they would be less resistant to wear than an OEM piston, but fine for racing applications where long life is less of a consideration. Although this makes sense, personal experience with gas engines tells me that racing pistons can last a long time in certain applications.

Of the 3 engines I did rebuild, all ran fine afterward. The first engine already has ~7k miles on it. I have had a few problems with oil leaks between the pan and the bedplate, so I'm trying to be more diligent about getting the right amount of RTV on the pan during assembly, and making sure the pan does not brush against anything before or during installation. One other issue was with blow-by which was a result of installing new rings in a pitted cylinder (a chance I took since I couldn't get oversized pistons).

As far as the crankshaft, I had several machine shops tell me they couldn't save the block once the bearings had spun. Since oversized bearings make up for lost material on the crank side, they had no way of fixing the block. If there was a bearing that would make up for lost material on the block side, then a line bore and crank polish would do it.

One last point... because there are currently no OEM (or aftermarket) oversized pistons available, I have been investigating other pistons that might work. I found one, and ordered a set at 83.5mm with pins, clips and rings (~$900), and have everything in the machine shop at the moment. The small end of the rod will need to be opened up about 0.001", and the pin land area (under the piston) needs to be opened up to accept the VM Motori rod. This piston is about 30g heavier, but it is well-constructed and has a pressed in steel ring supporting the 1st compression ring for durability. It uses chrome rings rather than moly, so it will require a little more break in time. The machine shop is backed up right now, so I probably won't find out anything else for a month or 2, but I will update once I have everything back.

Let us know how your build goes- sounds pretty awesome. Are you getting a custom tune?

 

[billetecodiesel]

I had also talked to Mahle and they said they wouldn’t be able to build my piston with the top steel ring. 50-60k and i would have blow by. To have the top steel ring made they wanted a minimum order of 1000 yeah i ended up going to a tractor pulling machine shop that said they would make my pistons and crank out of billet. Pricey but worth it in the end. Yes i use Ecodiesel USA custom tuning with a 5 position switch. Love the tunes and works well with my goals. 30mpg hand calculated with leveling kit and oversized rims and tires. Pistons and crank are about 10 months out because they are so busy but I’m building the trans, rearend, and chassis.

 

[67_Valiant]

Out of curiosity, what piston clearance are you running? The pistons I bought spec. 0.0015" piston to wall, which seems really tight, but they are also designed at 16:1 compression ratio, so I guess they need to be as tight as possible.

 

[billetecodiesel]

Piston spec i believe will stay the same unless my builder thinks it needs to change. But they will be thermally coated completely

 

[67_Valiant]

Piston spec i believe will stay the same unless my builder thinks it needs to change. But they will be thermally coated completely

OK. The VM Motori spec uses tolerance classes which makes it a little harder to follow unless you are using their pistons. I'm just going with what the mfr. for my new pistons recommends(0.0015") which is about in the middle of the range for the VM Motori tolerance classes (0.0009"-0.0031"). Since your machinist builds tractor pull engines, I'm sure they have a good idea of what it should be, which is why I was curious.

 

[JTJT]

Piston spec i believe will stay the same unless my builder thinks it needs to change. But they will be thermally coated completely

How did you build go.
I love the power of diesels and I have an ecodiesel I want to rebuild right now with tighter specs and better parts than Motori did.
Do you rebuild Ecodiesels for a living or do you just use the name billetecodiesel?
Have you found bearings that will make up for line boring the block?