I'm going to pull my diesel for a little "maintenance."

[Beefcake]

Casey, Thanks for the work you've done to keep us informed. I was wondering if you could share your rebuild costs with us? machining, and what kit you come up with... Thanks much- joe

[67_C-30]

[arveetek]

I talked to the shop yesterday and found out they had to bore it .030" over to get the cylinders cleaned up. They also decked it, and are ready to install the cam bearings. Should have it ready to pick up on Monday.

Right now, I'm going to have about $1400 invested in this rebuild. Luckily, I've been buying parts for it over the past few months, so that helps spread the cost out a little bit.

For $1400, I get new timing gear drive set, stud girdle kit, new lifters, new custom pistons and rings (the biggest expense), gasket set, machine work (block borned, honed, decked, and new cam bearings installed), and new motor mounts. I have yet to touch the heads, but I need to inspect them to see what kind of attention they need.

I didn't buy one master overhaul kit, because I wasn't intending on this big of a project. I've simply bought all the parts I needed separately and a little at a time.

Whatever you do, don't use anything but Fel-Pro headgaskets. I did some research into other manufacturers, including Detroit Gaskets and Corteco, and discovered that they are junk, at least for the diesels. Only Fel-Pro has done the research to make gaskets that will withstand the miles and miles of high diesel head pressures.

Now I have to decide whether to have the rotating assembly balanced. It will cost another $150, and they'll balance the crank, rods, flexplate, etc. I'm rapidly running out of funds on a project I didn't actually intend to do. Whaddya think? Is balancing worth the money?

Casey

[RockHQ]

Balancing the rotating assembly is always a good thing, like you must know. However, the effect of having an unbalanced rotating assembly is an equation of revolutions per minute times the weight bias of the rotating assembly, to put it simply. The higher the RPM, the more energy the weight bias will create. In reality it only really becomes critical at high rpms in an Otto engine. A typical diesel engine must first survive the torsional stresses created by the combination of high compression ratio and compression ignition. In case you didn't know, nothing can be done to a typical 90-degree V8 engine to achieve a perfect balance due to the geometry of the rotating assembly and cylinder banks. Almost all of traditional V8 engine balancing is done according to a single formula that's been been proven time and time again by experience to be the most effective compromise. A properly working 6.2 diesel engine has its injection pump rev. limiter set at 4100rpm. Spinning a 6.2 that high is insane.

Balancing a reciprocating piston engine has another point that's often overlooked. When a piston is on the compression stroke the compression of air creates pressure against the piston which is felt by the crankshaft as increased weight of the piston-rod assembly. Accordingly, during the combustion stroke the piston/rod assembly suddenly has no mass to speak of as it is being accelerated by the combustion gases.¨

Should you balance your engine internals? Yes, if you're going to RR your engine thoroughly.

[arveetek]

I ordered my pistons this morning. The Diesel Depot said they'll offset the wrist pin location by .010" to compensate for having the block decked, and then they'll shave another .010" off the top of the piston to lower the compression, and then they'll ceramic-coat 'em to top it all off. They had to order the .030" over pistons, but should have them by Wednesday, and then hopefully have them ready to ship by the end of the week.

Compression ratio should be somewhere between 19.75:1 to 20:1.

Casey

[Beefcake]

arveetek

Im glad you responded about your "custom pistons" I didnt know what you ment at first. I hope you take rock hq's advice and balance everything... Just not worth throwing all that money in and not spending the extra $150 for security.

I was wondering about your machine shop. Im very happy with the guys here that I deal with, they've been around forever. They just built an awesome 383 for me... But I was surprised when I asked about working on diesels- they said they havent worked on many!?!?!....

[67_C-30]

How's the rebuild coming Casey? I got my 6.2 pulled out, and I'm getting ready to turbo it. I got the manifolds today (pics below) that I got off Ebay. I also got a Nintendo cover today. I've also been looking at several different intercoolers that I may try to fit in my truck.

[arveetek]

Originally Posted by 67_C-30

How's the rebuild coming Casey?

Sorry I haven't responded until now....been really busy lately. Plus, my wife and I went skiing in Colorado last week over Spring Break. I just got back to work yesterday, and I'm swamped!!

I'm still waiting for the pistons to come in. Should be here any time now. I've ran into problems with the heads, though. My original heads were really worn out, and had trashed exhaust valves. It was going to cost about $650 to repair them, plus they had a lot of "questionable" cracks. I had the shop check out the heads on my spare '83 engine, and they were much better, but one head had severe rust pits on the exhaust manifold side. They said I'd be better off not using them, for fear of having exhaust leaks.

So, I purchased a complete, but bad, 6.2L engine from my uncle for $50. It's an '86 model out of a van that threw a rod several years ago. Heads look good, though. I'm waiting for the shop to give me the results of inspection of these heads, but I'm pretty confident we've got a good pair. Surely out of 3 engines I can build one good one!

The only problem with going to newer heads is that I'll need new injectors. My current injectors are coarse-thread, and won't screw into the '83 and newer heads. I don't want to install the used fine-thread injectors on a new engine, either. So now I'm looking at buying new 6.5L turbo injectors that have a higher pop pressure. I may have the pump refreshed as well.

So, now I'm looking at about $2500 for my rebuild. I think I'm about at the end of the spending, though.

I can't wait to get all my parts and get it back together!

Casey

[67_C-30]

I think I'm going to have to go with 6.5L injectors. I read on a Diesel forum that that some of the long 6.2L injectors interfere the RH manifold. I don't know if mine are considered long or short. Do you know what the lengths are?

[grape]

tell your injection shop to put "311" nozzles in your short 6.5 injectors.........you'll like it. I've got some extra cores if you need them, and some prechambers for the straight angle turbo heads. Actually have a whole set of heads, they have the cracks between valves but i haven't disassembled them to see if the seats are cracked like the other set's I've dug through.

[86dieselburb]

$2,500 isnt bad for a rebuild if ya ask me. I've got a 310k mile 6.2 thats getting close to rebuild time. Thanks for posting this info. The more info available the better.

[Beefcake]

Thanks for keeping us informed casey!