Engine/Transmission (1994 - 1998) Need turbo suggestions for my Cummins HMMWV

[CStansbury]

Hi All,

I have a swap project going on at the house right now. I know we have a conversions forum, but thought this would be a better place to post since it is 12v engine specific.

I have a 1995 190hp 12v from a Ford bus sitting where the 6. 2L used to reside in my 1985 M998 humvee. It only has around 95k miles on it and was clean as a whistle on the inside when I swapped out the front sump pan.

I was planning to use it 100% stock initially and then start tinkering with the power later on after some drivetrain upgrades. My plan ran off track when I noticed that the H1C turbo compressor wheel had a small chunk broken out of the center section right by the shaft hole. I have no idea how long it has been broken or where the piece went. The engine ran great when I bought it, so hopefully the chunk got hung up in the bus' intercooler.

So, here's a background on the humvee: It will end up weighing around 6500 lbs, it will run the stock TH400 trans initially and a built 4L80E or 47RH later on, and it will be riding on 37" tires initially and 39-40" tires later on. I don't plan on towing more than 1500 lbs in the form of a small military trailer and that won't happen very often. The truck will see most of its use during the week on paved roads driving around the mountains of West Virginia and then running trails on the weekend.

Any thoughts on whether I should replace the H1C with another H1C, rebuild the H1C or swap it out for another turbo like the HX35? Thanks for any advice!

 

[Joseph Donnelly]

You should replace the turbocharger with a quality rebuilt unit because the damaged wheel causes the rotating assembly to be out of balance. If you add a substantial amount of fueling, you will want a somewhat bigger turbocharger, such as the BD Super B (which would work even with stock fueling). You need to "contain" the Killer Dowel Pin and check the stock exhaust manifold closely; it has probably shrunk and is putting a side load on the end mounting bolts. Eventually it will break bolts or ears on the heads if you don't replace it. Space permitting, use an aftermarket 3-piece exhaust manifold.

 

[1972JohnBoy]

You are the man joe

You should replace the turbocharger with a quality rebuilt unit because the damaged wheel causes the rotating assembly to be out of balance. If you add a substantial amount of fueling, you will want a somewhat bigger turbocharger, such as the BD Super B (which would work even with stock fueling). You need to "contain" the Killer Dowel Pin and check the stock exhaust manifold closely; it has probably shrunk and is putting a side load on the end mounting bolts. Eventually it will break bolts or ears on the heads if you don't replace it. Space permitting, use an aftermarket 3-piece exhaust manifold.

I can't help but say how much I appreciate the experience and wisdom Joe brings to us here. I have not had the chance to meet him but hope to in the future. This goes out also to all the writers and staff of the TDR. I had the pleasure of meeting some of you at Columbus this summer. This is worth much more than the yearly cost of subscription ! John

 

[Simplysmn]

The Hummer Network Forums :: Log in your best bet is go here an contact member TODD he has a cummin's powered humvee he might beable to help you out . And if you need tires n wheel's send me a PM I can get the new style 24 bolt wheel's n New baja ta tires for the Humvee

 

[CStansbury]

You should replace the turbocharger with a quality rebuilt unit because the damaged wheel causes the rotating assembly to be out of balance. If you add a substantial amount of fueling, you will want a somewhat bigger turbocharger, such as the BD Super B (which would work even with stock fueling). You need to "contain" the Killer Dowel Pin and check the stock exhaust manifold closely; it has probably shrunk and is putting a side load on the end mounting bolts. Eventually it will break bolts or ears on the heads if you don't replace it. Space permitting, use an aftermarket 3-piece exhaust manifold.

Thanks Joe. I will look for a rebuilt H1C or a good deal on a Super B. I tabbed the KDP while it was on the engine stand. I looked at the manifold and it seems like the bolts are all still straight. I like the packaging of the Ford manifold because it positions the turbo to the rear and helps with clearance issues. Do any of the aftermarket manifolds have that setup?

I can't help but say how much I appreciate the experience and wisdom Joe brings to us here. I have not had the chance to meet him but hope to in the future. This goes out also to all the writers and staff of the TDR. I had the pleasure of meeting some of you at Columbus this summer. This is worth much more than the yearly cost of subscription ! John

I agree!

The Hummer Network Forums :: Log in your best bet is go here an contact member TODD he has a cummin's powered humvee he might beable to help you out . And if you need tires n wheel's send me a PM I can get the new style 24 bolt wheel's n New baja ta tires for the Humvee

Thanks for the offer on the wheels, but I already have a set of 24-bolt's sitting in the garage. I'll be running 39-40" tires once it is all said and done. There are some good folks on the HNF. I will look TODD up.

 

[Joseph Donnelly]

Dodge type aftermarket exhaust manifolds have center outlet (if for first and second gen) or rear outlet similar to yours (if for Third Gen). Let me know if you need help in finding a deal on the turbo, etc.

 

[CStansbury]

Dodge type aftermarket exhaust manifolds have center outlet (if for first and second gen) or rear outlet similar to yours (if for Third Gen). Let me know if you need help in finding a deal on the turbo, etc.

Thanks Joe. I forgot about the 3rd gen trucks using the rear outlet manifolds. I haven't looked under the hood of one since I sold my '04. 5.



I will certainly accept your help finding a deal on a turbo. I really just need the turbo, not the kit, since I will have to fab my own down-pipe, oil drain, intake, etc... Depending on the price, I may have to go the used/take-off route.

 

[CStansbury]

Another option that just occurred to me is running a HX40. I have one left over from one of my military truck projects. It's off of a Cummins 8. 3L. Maybe that would work well with the right fueling and timing combination?

 

[CStansbury]

OK, well now I feel relieved and a little stupid. :{



I was talking to a guy at the local diesel shop about rebuilt H1C turbos and he told me that the cracked area that I was seeing on my compressor wheel may actually be a machined area that was used to balance the turbo. I got a flashlight this morning and checked it out. Turns out he was right. Some oily residue made it look cracked, but I cleaned it up and it turns out that it was machined in that spot. Sorry to lead y'all on a wild goose chase. At least now I know better and don't have to swap out my turbo right away.