Hey everyone,

look the 6.2/6.5 has to be the largest piece of &^%$ gm has ever made ,
I have a 1987 1 ton on singles 6.2 rebuilt(EVRYTHING NEW 5K invested)
the problem with these engines is not anuff cooling , 7 & 8 get hot the piston grabs the walls and brakes rods mostly shoving through the block , mine broke a rod close to the crank , stoved 2 holes in the oil pan and blew the starter off on the ground , didnt hurt the block or crank , im not interested in rebuilding this engine again im going to use to for parts for my other 86 6.2 , my question is not how hard it is to replace the 6.2 with a cummins but does anyone make a bell housing convertion kit/out put shaft from the man 4 speed to a cummins?

the cummins is 1500 to rebuild and a way better engine .
the engine i want to put in is a norm asperated 12V cummins.
i know you have to do a 2" lift to get the engine to clear the fire wall

Thanks
Doug

i'd suggest not letting the same people rebuild the cummins that rebuilt your 6.2. GM bread wagon vans had the 4bt with a turbo 400 so the bellhousing adapter is available, just have to find one.

Biggest piece of (censored) that GM ever made? Nope, wrong answer here, think POS, think 5.7 diesel. Anyways, I think the problems you're having with your 6.2 and cooling are probably simple, maybe just using the correct thermostat. I've had problems with cooling in the past and they were all fixed by a properly rodded radiator, working fan clutch and a 180 degree ROBERTSHAW Hi-flow design thermostat. I know for sure that the 6.2 is one engine (in non turbo form) that can be worked HARD and stay together.

But for the cummins route, Grape is right in that a 4BT adaptor used in a lot of bread wagons will work behind the 6BT. Why are you going to be non turbo on a Cummins, that will be more gutless than a 6.2 for sure.

And... As stated, find yourself another builder..

Sorry to hear your troubles with the 6.2, but sounds to me that whoever machined your block didn't give you enough clearance on your pistons. Another problem with rebuilding 6.2's or 6.5's is the quality of pistons or should I say lack of quality. Your problem is not a common problem and needs to be blamed on too tight of piston to bore clearance.

As for your cummins swap, take a gander at the TDR website and do a search under chevy conversions and you will find a ton of info, including some pictures of my Burb.

Rather than going with the old 4spd, why don't you just use a New Venture 5 or 6spd trans? They bolt right up. Why no turbo?

I for one would love to know where you can get the parts to rebuild a 6bt cummins for $1500! even a 4b you can;t do it that cheap.
Unless you plan to just put in rings and gaskets and call that a rebuild, which may be the case after looking over your post and seeing the problems with your other engine.
please do let us know. i would have people standing in line to buy the parts for that price.
brian.

My mistake , the engine i want to be putting in is a turbo model , the 6.2 was rebuild with me standing right beside , the 6.2 engine was bored , aline bored the crank was a reman crank assembly , new pistons , new gm head's & gm injectors , new fuel pump , new ac glow plugs , new thermostat , brand new 4 core rad , it was timed at a gm dealer before ever starting , i always used fuel conditioner , the rod might have just had a flaw in it , but i was never happy with the power , I have a call into my parts supplier for my cost on a rebuild kit for the cummins sleeves , pistons , gaskets , bearings , water pump , oil pump and i will let you know . my price will reflect jobber less 10%

my reasoning behind using the gm 4 speed : as long as you dont run it out of oil you wont brake it or i wouldnt , the transfer case is bullet proff compared to the dodge transmission and transfer case , in 1997 dodge had over 50 diffrent transfer cases in these trucks .

By almeans im not saying that the truck will have a cummins in it , you guys and gals can talk me into something else as long as its not computer controled but i would really like to use the gm 4 speed and trasfer case .

thanks
Doug Gritner

Piece of XXXXX - NOT !! With 259,000 miles on one and 500,000 miles on another 6.2, I hardly could say either of mine were junk.

Good luck on your conversion .

What is the web address of the TDR web site?

Cougar John, try this http://www.turbodieselregister.com/;)

Petrols, when I said too tight of clearances it means that there might not have been enough room for expansion. #7 and #8 should be set up slightly looser than the rest of the pistons because they get hotter. Piston quality is also an issue. What brand of pistons were used in your 6.2 build up? Do you have an egt gauge? I have seen many instances of pistons welding themselves to the cylinder walls and they are all caused by heat, but usually too high egt's. The last couple that I saw were CUMMINS 6bt's, they are not immune. They just have bigger bearings so the rod usually isn't a problem. I question if your connecting rod actually broke, these rods are forged high quality parts. I think what probably happened is the piston expanded too much welding itself to the bore and failed the bearing and then the crank wore through the upper part of the rod until it failed. Am I close? All pistons are not created equal, just ask any racer. I have had similar experiences with a 6.5 with the pump turned up and towing very heavy with a post turbo pyro and that is why I will NEVER trust a post turbo pyro again!

The last 6.2 that I installed for a customer was a custom built engine that just didn't seem to run right. I suspected a bad injection pump and after much tearing things apart I was right. This engine was retarded over 6 degrees with the pump advanced as far as it would go. The egts would easily hit 1300 degrees with no load. Once the injection pump was replaced the egts wouldn't go over 600 degrees. By the way the engine had a new rebuilt pump as the engine was fully dressed. I will not mention the name of the rebuilder, lets just say that they build a lot of 6.2's and have a good reputation, but this fully dressed 6.2 didn't have the flex plate bolts tightened by them and cost me a lot of extra work to remove the trans and transfer case to put another flex plate in after 4 miles of driving. So if I dont have anything nice to say I won't say any more!-:t
Luckily for my customer, no damage was done and the fact that he invested in a pyro and Banks exhaust for his 6.2 probably saved his engine. Gauges are a good thing.:rolleyes:

D.C.: Thanks for the web address of TDC.