The CUCV Build-1986 M1031 Mobile Field Maintenance Assault Vehicle
- Thread starter PlethoraOfGuns
- Start date
chilliwak
Expedition Leader
I am really sorry to hear about your engine breaking down Plethora, but then again now you get a new engine. I have read a lot about those optimiser motors and have only heard good things. Just curious what you payed for that motor. At some point in time I will need to be replacing my 6.5 TD in my Yukon and am interested to know if an optimiser will work in my rig. Does the intake off a GM 6.5 work on an optimiser? Can you use exhaust manifolds off a GM 6.5 on the optimiser? I will be following your build and look forward to seeing what you do. Cheers, Chilli...
PlethoraOfGuns
Adventurer
Yea, these engines are supposed to be pretty awesome. Still not expecting a powerhouse, but just fine with the workhorse that they are. I've always wanted to take blown up engines and done some kind of coffee table thing, but that's a lot of cleaning! I got the engine from Ted's Trucks down in Alabama. Talk to Margeret, she's awesome and full of that nice southern hospitality.
I think they have a contract with the government so when the military gets bored and repowers the HMMWV's with new engines for no reason and throws the almost brand new engines into the dumpster, Ted's gets them. They run through them, bench test them, and sell off the good ones. Their prices always vary. I don't like to promote or demote peoples prices on the interwebs, so you guys can go look it up on your own. Margaret has all the answers for you.
For twice the price, I could have bought a new one, but with the fact that I could have gotten a used 6.2L for $600, I didn't want to spend way too much money. If I was gonna spend $6000 on an engine or something, it would be a Cummins or something, if we had the time. But this will work, and I'll feel better knowing I'm helping the environment by using a recycled engine!
The 6.5L Optimizer shares the same exterior specs as any old regular 6.5L. So yes, any intake manifolds, exhaust manifolds, and turbo stuff will bolt right up to it.
I think they have a contract with the government so when the military gets bored and repowers the HMMWV's with new engines for no reason and throws the almost brand new engines into the dumpster, Ted's gets them. They run through them, bench test them, and sell off the good ones. Their prices always vary. I don't like to promote or demote peoples prices on the interwebs, so you guys can go look it up on your own. Margaret has all the answers for you.
For twice the price, I could have bought a new one, but with the fact that I could have gotten a used 6.2L for $600, I didn't want to spend way too much money. If I was gonna spend $6000 on an engine or something, it would be a Cummins or something, if we had the time. But this will work, and I'll feel better knowing I'm helping the environment by using a recycled engine!
The 6.5L Optimizer shares the same exterior specs as any old regular 6.5L. So yes, any intake manifolds, exhaust manifolds, and turbo stuff will bolt right up to it.
KE7JFF
Adventurer
I think these 6.5 motors were from the HMMMV Recapitalization program; as I understood, there were some rebuilds they put in crates for quick exchanges at the inventory level; send back the bad engine as a core, a fresh engine gets sent out.
I would love to get a 6.2 though in my 89 Suburban....as I understand, they bolt right up to my TH400 as it was a option.
I would love to get a 6.2 though in my 89 Suburban....as I understand, they bolt right up to my TH400 as it was a option.
XJSuperman
OhIOWAn
I believe so. 6.2s were in all the m1009s with th400s. Though the overdrive 700r4 is really nice, so I hear
The Grinch
Member
Most will agree the 6.2 was no great engine. It was a fuel saver and comperable to a 305/350 v8 depending on trim and IP. They are far from a junk engine everyone thinks them to be. Which is fine by me keeps them cheap.
Fact is this is not a gas converted diesel. Do the research man , that was the OLDS 350 based diesel that came out before the 6.2. Its funny how so many people hate these yet the government used them, The postal used them, Many towns school bus fleet use 6.5's.
A cummins 5.9 is hands down a better engine but the 6.2/6.5 is a decent engine.
Sick build man I think the optimizer will be good to you. hear nothing but great things.
Fact is this is not a gas converted diesel. Do the research man , that was the OLDS 350 based diesel that came out before the 6.2. Its funny how so many people hate these yet the government used them, The postal used them, Many towns school bus fleet use 6.5's.
A cummins 5.9 is hands down a better engine but the 6.2/6.5 is a decent engine.
Sick build man I think the optimizer will be good to you. hear nothing but great things.
PlethoraOfGuns
Adventurer
The 6.2L is nowhere in the same league as the 5.9L but it has it's place. The military uses the 6.2L/6.5L because they are inexpensive, reliable, all mechanical, and more or less fuel efficient. Something about the 6.5L is good because when GM stopped comercial production, the government had somebody else keep making them for their own equipment. I learned the hard way that these old 6.2L's shouldn't be driven 20k miles humming away at 4000rpm. Wish I had that overdrive unit earlier... And yes, we all wish we had Cummins' in all of our vehicles, but sometimes we just have to deal with life as it is. Could use a Cummins in this truck, a Jeep, a 1974 AMC Gremlin, or even mom's old minivan. It's just an engine, we're not building racecars, just trying to get lost out in the world...
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Anyway, back to the good stuff...
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So the HMMWV 6.5L oil pan wasn't going to work with the solid front axle setup.
The stock 6.2L oil pan has a different curvature around the rear main seal. So found a stock civilian 6.5L oil pan from the junkyard that will work well.
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But the stock civilian 6.5L oil pan won't fit on the block with the HMMWV oil pump. So we had to convert the oil pump over to a civilian 6.5L pump.
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Once the oil pan issue was figured out, everything else went smooth. Just bolt everything on and off we go.
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All ready to drop in! :sombrero: Bunch of new parts, Should be able to drop it in real quick and turn the key and back on the road.
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Anyway, back to the good stuff...
.
So the HMMWV 6.5L oil pan wasn't going to work with the solid front axle setup.
The stock 6.2L oil pan has a different curvature around the rear main seal. So found a stock civilian 6.5L oil pan from the junkyard that will work well. .
But the stock civilian 6.5L oil pan won't fit on the block with the HMMWV oil pump.
So we had to convert the oil pump over to a civilian 6.5L pump..
Once the oil pan issue was figured out, everything else went smooth. Just bolt everything on and off we go.
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All ready to drop in! :sombrero: Bunch of new parts, Should be able to drop it in real quick and turn the key and back on the road.
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KE7JFF
Adventurer
Werid it had a different oil pump....you would think they wouldn't change that...
And yeah, the the 6.2 after I talked to some real diesel shop guys here in Portland to get the straight dope told me its a decent engine as while it was meant for light trucks, Detroit Diesel did most of the engineering work on it so there is some expectations with that. The crankshaft issue that is common to the 6.2 and 6.5 as my contacts have told me from their experience is from pushing the engine to the extreme too often; for example towing a trailer uphill at 70 MPH with the AC on during a 100+ degree day...
And yeah, the the 6.2 after I talked to some real diesel shop guys here in Portland to get the straight dope told me its a decent engine as while it was meant for light trucks, Detroit Diesel did most of the engineering work on it so there is some expectations with that. The crankshaft issue that is common to the 6.2 and 6.5 as my contacts have told me from their experience is from pushing the engine to the extreme too often; for example towing a trailer uphill at 70 MPH with the AC on during a 100+ degree day...
XJSuperman
OhIOWAn
Or a turbo on it and run it hard. The predecessors to the 6.2 were the REALLY bad ones. They were literally gassers converted over. Somewhere on SteelSoldiers there is a thread on the "6.2L Dream Build" listing nearly every piece down to the detail and what years or serial numbers each piece was made in. It would be more work than the motor is worth, but a neat idea nevertheless.
6.5 looks good bud, can't wait to hear what you have to say once its in the truck.
6.5 looks good bud, can't wait to hear what you have to say once its in the truck.
chilliwak
Expedition Leader
Glad to see your motor ready to install mr Plethora. Your truck is too cool to be standing around without the ability to be driven. So did your new motor come with new exhaust, intake, and other things? Other than the oil pump isue did you have to do any major conversions? Cheers, Chilli...
KE7JFF
Adventurer
Well, some of the gasser conversion like the Olds Diesel was actually an almost genius design; the block was bulletproof but the weak point were the heads and the head bolts; if they didn't decide to maintain tooling capability with the Olds 10-bolt head pattern among other things, they could of had a stronger block. And as anyone who works diesel knows, bad head design is a great way to kill a engine...
PlethoraOfGuns
Adventurer
Yes, the oil pans on all 3 engines are different indeed, and so are the oil pumps. But good thing is that the civilian 6.5L and HMMWV pumps bolt up the same and are interchangeable. The real problem is the dimensions and where the pickup sits in the pan.
Got the engine in. Went in nice and smooth. New engine mounts lined up perfectly.
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Putting all the other componants together went ok. Fuel lines, vacuum line for transmission, starter, all good. The problems occured with engine oil stuff. The whole dipstick tube setup is different. The connections on the engine for the oil cooler lines are a different size. Little hiccups like that. The HMMWV dipstick tube just wouldn't work with the engine bay. I could not locate a civilian 6.5L dipstick tube. apparetly, junkyards break them off and throw them away and dealers no longer carry that part from more than 15 years ago. So I took the 6.2L dipstick tube, cut it down, bent it a bit, and remarked the dipstick to read a different oil height in the pan. To get the stock oil lines to hook up, I just got some adapters that threaded into the block and worked with the existing flare fittings.
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Even had a little helper for putting everything together.
Got the engine in. Went in nice and smooth. New engine mounts lined up perfectly.
.
Putting all the other componants together went ok. Fuel lines, vacuum line for transmission, starter, all good. The problems occured with engine oil stuff. The whole dipstick tube setup is different. The connections on the engine for the oil cooler lines are a different size. Little hiccups like that. The HMMWV dipstick tube just wouldn't work with the engine bay. I could not locate a civilian 6.5L dipstick tube. apparetly, junkyards break them off and throw them away and dealers no longer carry that part from more than 15 years ago. So I took the 6.2L dipstick tube, cut it down, bent it a bit, and remarked the dipstick to read a different oil height in the pan. To get the stock oil lines to hook up, I just got some adapters that threaded into the block and worked with the existing flare fittings.
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Even had a little helper for putting everything together.
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PlethoraOfGuns
Adventurer
Got everything all put back together, primed the fuel system, and who woulda thunk, she started!
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As an added plus, the whole swap was done with all the tools that are stored onboard the rig, excluding the engine hoist and stand.
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Dropping her temporary jail cell and leaving the driveway.
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Driven across town! Looks like we're back in business...
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As an added plus, the whole swap was done with all the tools that are stored onboard the rig, excluding the engine hoist and stand.
.
Dropping her temporary jail cell and leaving the driveway.
.
Driven across town! Looks like we're back in business...
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