replacement 6.2

LT67 said:

Good morning,

Not that I need a replacement engine, but I want to be clear in case I have to any time soon..

A HMMWV 6.2 and a 6.5 Optimizer long block will drop right into my M1008 with no problems correct? And all I would basically have to do is transfer the accessories from my current 6.2 over to another long block correct? An Optimizer will need a difference oil pan correct?

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The oil pan for the optimizer you would need is from a 1993 and newer civi 6.5. This is because there is a bigger one piece rear main seal. Other than that you can use your 6.2 parts. You will need the water pump backing plate to use your V-Belts and dual alts. Also the optimizer has 1/2-14 threads for the oil cooler lines. While the 6.2 uses 3/8-18 threads. But you can get bushings from almost any hardware store to reduce them. This will allow you to use the stock oil cooler lines. The 90 deg oil filter housing it the same one used in the 1990's four wheel drive trucks. Simply remove it. Then remove the steel threaded part that the filter threads on. Use this part to screw into the block. Now the filter will mount on the block just like the 6.2

I believe the first thing you must do is to establish your goals for your truck. If you plan to keep the truck, and want to simply stop the leaks, have the tools and can follow the instructions in he TM, a head job is not that difficult. There will be plenty of free advice help here on SS. But if you don't plan on keeping the truck or think that a head job is to involved or too expensive, heck just get rid of the thing and move on. If you solicit 10 replies on this forum regarding what you should do, you will probably get 10 different opinions. I learned 50 years ago to quit listening to others and instead, listen to my heart. Sometimes it takes me years to put a plan into action. I've been restoring/rebuilding/modifying my M1028 since 2010, and I am just now getting to the juicy part of installing a new engine and transmission. Settle on a course of action, then sleep on it for a while and see if you change your mind. Second-guess yourself and play devil's advocate. Learn to deny yourself. Imagine a course of action completed, and then imagine how it feels. Once you work through all these processes, then you can take the next step, regardless what that may be.

Hope this helps.

cucvrus said:

the leak at the rea of the head could be a vacuum pump leaking, an oil pressure sending unit, valve cover or something else..

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I have checked out the leak from every possible angle, dry up top where the vacuum pump sits, even my mechanic agrees..its the L head outside rear corner. If only it was the valve cover. Here's a pic I took.

Any downside to an engine that's been sitting around for a number of years? I'll assume its under cover and not full of water.

Why would someone sell an engine full of water? And did you remove the steel clamp on the oil cooler lines. That is where my plow truck Voodoo M1009 broke off and lost all the oil and locked up the engine. That steel against aluminum reaction. But I have my engine in the dry and exercised every few months. Not sure who you were directing that at. If it were not so far. Good Luck.

I haven't removed any clamp from the lines, there is a clamp in the pic, are you referring to another one?

The water remark wasn't directed at anyone, a guy up here is selling a 6.2 thats been sitting around for a number of years. Just wondering if there's any detrimental effects like rusting of the cylinder walls etc. The water remark was in case it was sitting outside and not properly covered..just conjecture.

Questions regarding a 6.2 out of a Humvee, that I might have a deal on. Its low-mileage and in a running vehicle, guy will check for blow by. I know brackets and pulleys need to be swapped from mine. Oil pan needs changing, how about oil pickup? Water crossover pipe is different with 2 outlets? Is the intake manifold the same, with CDR plumbing etc? Can I use the IP with just a 12V solenoid swap, is it the same , will the transmission Vacuum Regulator Valve etc swap on? There are some sensors that also need to be changed? Are the exhaust manifolds the same? Anything else?

I know from experience that the intake is totally different. Scrap aluminum if you have a CUCV. If your injection pump is good and you know it use yours. The oil pump pick up I am NOT sure is different but just get a new oil pump and use yours. The water coolant cross over manifold has only one outlet/inlet. The sending units in it can be pipe plugged. But once again use the CUCV one. I would use the bare long block from the HMMWV and use everything off of your engine. The water pump may need replaced. get a new one for the CUCV. Good luck. Replace all the seals and gaskets while you have it out and do it right. Drive on.

Matt5 said:

Tranny no good for cucv
Everything on motor no good for cucv

You legit just linked a $3,250 block to someone... wow...

Even the injection pump is no good (24 volt vs 12 for cucvs)

6.2's higher end tend to be around $1000 for a cucv...

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On what are you basing your post ? a GM 6.2 is a GM 6.2 no matter what it's in. The "problem" is the accessories, not the engine itself. Eastern is a very good, reputable company. Just wondering where the info came from on your side.

I gotta start reading to the end before throwing in. Sorry y'all.

You can swap the top of the IP with the 24V shut off. The CUCV 12V will work on the Humvee pump.

Alright... so I will need to swap my intake manifold with all the CDR plumbing over. But I can use the IP, lines and injectors. This motor is low mileage so I would use its IP, as mine.. although still running good has 200,000 miles. And the water pump? I read that's its the same rotation as a CUCV.

Don't you have that engine in and running yet?

Heck after reading the thread for about the same money you could put a 1st gen 12v Cummins 5.9 in it and run it forever.

KamikazeKunze said:

Heck after reading the thread for about the same money you could put a 1st gen 12v Cummins 5.9 in it and run it forever.

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Yea that would be a great way to put it in a fix. But not fix any of the current issues he is experiencing. I think he wants a bolt in solution to the engine issue. He seems happy with the 6.2 and just wants to refresh it after 200K. I think so anyway. Simple 2-3 day fix and back on the road.

A cummins would be nice, but that presents many challenges. Dropping a 6.2 or 6.5 in is a direct replacement. No modifications necessary. Plus the p400 block he is getting will be putting out the same hp and tq numbers as a stock 2002 cummins.

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cucvrus said:

Don't you have that engine in and running yet?

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Its a guy who works in the movie industry, Humvee was rolled, he needs to peel parts off to run it and check it out. Then pull it. Yeah, its been a couple of weeks, he's busy. don't want to pester him. So it will happen when it does, nothing I can do about it.