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FEF
10-25-2007, 08:52
All,

I'm running into quite a few 6.2's, for my motorhome conversion. This is a great thing, but I've not owned one, so I have no first hand experiance with this engine. I need a bit of help.

The engine was made for ~10 years. I've seen a lot of '82-85's, but none (with the mechanical pump) from '90-'93. I undersatnd that the 93' is something like the holy grail of the type, but are the early years so bad?

I expect I'll need more power a bit later. Will the earlier models be well suited for a reasonable amount of boost from a turbo? I was thinking I might try the 6.5 turbo conversion in a few years.

I really don't think I can go horrably wrong, but I could use some advice if there's a year span that's not as desirable.

Thanks for the help

FEF
10-25-2007, 09:12
Sorry for replying to my own post :eek::cool:

I don't know why I didn't find this before (search engines can be tricky), but this thread lists a few nasty issues.
http://www.thedieselpageforums.com/tdpforum/showthread.php?t=27834

I understand all engines have their weak points, but what should I really be conserned about? Maybe a new balancer and flywheel, to help the crank issue?

I've seen a number of engines under 40,000 miles, some even crate engines. I really don't want to rebuild now, but should I be conserned?

I'm sure it sounds worse then it is. ;)

ccatlett1984
10-25-2007, 16:50
replace the balancer if it looks questionable at all, the flywheels arent known for causing issues. for a conversion you will want an engine with a mechanical injector pump (no computer to deal with) although any 6.2/6.5 can be run with a mechanical pump in place of the computer controlled pump.

WeaselWerks
10-26-2007, 23:57
The general consensus that keeps coming up time and time again is the balancer issue (replace if any doubt, get the FluidDampr if you've got the cash and want a 'lifetime' solution), as well as the issues with main-web cracks and snapped crankshafts.

The short is have your block inspected for the main-web cracks, if your good in that respect you might want to look into a stud-girdle kit, or something more exotic (search for Grapes' 6.2 full-girdle). As for the cranks, magneflux (or otherwise NDT) it at overhaul, and never have it ground (only polished). If the crank has survived several hundred thousand miles of service and the damper is maintained, it would seem the cranks will last forever (if you maintain your engine). I agree with ccatlett1984, that if your flex plate is in decent condition (nothing falling off), it won't contribute to a crank failure.

As for power upgrades, the engine will handle mild boost from the banks kit, but install an exhaust pyrometer, because excessive EGT's will kill even the best built 6.2's.... And make sure your cooling system is up to snuff...

I myself purchased a used 6.2 from eBay for a conversion, 1992 J-code, 660 block casting, with +137k miles... This engine had seen some tough service when I got it... I've sunk quite a bit of money into it since then, but since the engine had a puked head-gasket (it had been gone for so long there were cylinder pitting issues and cylinder head cracks around the valve seats) and I hate to half-ass a project, I decided to go with a complete overhaul.

With that said, it comes down to how the motor was run... Frequent overheating and inadequate maintenance, that motor could be near-dead after 40k. If you have something that hasn't been abused, and you should be good for hundreds of thousands of miles, if it's maintained.

It also depends what your planning on sticking this motor in (GVW wise).... If your thinking a 6.5 turbo setup is a necessity, it's better now to invest in the proper parts, like low-compression coated pistons, or just look for a mechanical 6.5L from the get-go.

Provide more details on what you've got in mind for your project, and you'll get tons of sage advice from the members here. ;)

FEF
10-28-2007, 09:22
Provide more details on what you've got in mind for your project, and you'll get tons of sage advice from the members here. ;)
As noted in the conversion forums, I'm trying to put a 6.2/6.5 in an early Revcon (motorhome) that uses the Toronado (front wheel drive) drive train. The issue at this point is the oil filter placement. The filter can not go there because that's where the tranny is, and I'm not sure I have the 1" clearance for the remote filter adapter.

I'm fidning a lot of trucks with newer 6.2L crate engines. I was hoping to buy one of those trucks, and swap engines (diesel in motorhome, Olds 455 in truck). These trucks mid 80's run very well, and actually show signs of new engines.

I just don't know if I should hold out for a '92-'93 6.5L, or if the newer 6.2 will do. It sound like I should hold out for the 6.5, becasue I can't inspect the webbing from the outside. Also, it sound like the 6.2 won't handel a conbined weight of 19,000 lbs.

Thanks for the help