1995 M1097 A1 Issue LEO Vehicle

[krazyk]

Hello everyone. I picked up our Department HMMWV from Fort Polk (LESO program) a few days ago and need some help. I'm a Lt. and our SRT Commander with extensive mechanics background but have limited knowledge on the GM 6.5 diesel and no experience with the M1097 A1. I have all the Army manuals that came with it and downloaded the others from your site but still need some clarification.
Our vehicle info is: 1995 NSN# 2320-01-371-9583 Ser#162416. It has a few issues. I replaced the batteries with new 6TL's, checked fluids, and saw that the oil pressure gauge shows zero. We verified there is oil pressure so we next pulled the sending unit. Its a Stewart Warner. According to what I could find, the replacement is 6620-00-993-5546? Is there a new or better part number or source for these? Also does a faulty sensor shut down the electric pump (transfer pump) like on the civilian versions of the 6.5?
Sorry for the dumb questions but the Military makes it tough to track down parts for these. The good news is they are nice enough to give us anything we ask for through LESO free of charge.

 

[simp5782]

Hello everyone. I picked up our Department HMMWV from Fort Polk (LESO program) a few days ago and need some help. I'm a Lt. and our SRT Commander with extensive mechanics background but have limited knowledge on the GM 6.5 diesel and no experience with the M1097 A1. I have all the Army manuals that came with it and downloaded the others from your site but still need some clarification.
Our vehicle info is: 1995 NSN# 2320-01-371-9583 Ser#162416. It has a few issues. I replaced the batteries with new 6TL's, checked fluids, and saw that the oil pressure gauge shows zero. We verified there is oil pressure so we next pulled the sending unit. Its a Stewart Warner. According to what I could find, the replacement is 6620-00-993-5546? Is there a new or better part number or source for these? Also does a faulty sensor shut down the electric pump (transfer pump) like on the civilian versions of the 6.5?
Sorry for the dumb questions but the Military makes it tough to track down parts for these. The good news is they are nice enough to give us anything we ask for through LESO free of charge.

That is a standard oil pressure transmitter that goes on a deuce, 5ton, etc. Just swap over to a mechanical gauge if you want accurate and no issues. a standard mechanical gauge will replace what is in the instrument cluster. I would do the same for the coolant temp as well. Plus they are 1/3 the price for the whole setup over just the sender.

 

[krazyk]

So the sending unit has nothing to do with the transfer pump like the 6.5 civilian version? There's no electric transfer pump just the mechanical one?

 

[simp5782]

So the sending unit has nothing to do with the transfer pump like the 6.5 civilian version? There's no electric transfer pump just the mechanical one?

All mechanical. The wire from the sender goes right to the gauge.

 

[ken]

The fuel pump is located at the front bottom passenger side of the engine block. Just like a 350 chevy. Also check the sticky at the top of this forum for the LEO checklist. We have added some civi part numbers for various items.

 

[krazyk]

Also check the sticky at the top of this forum for the LEO checklist.

Sorry about that, I did some searching but didn't see that part. I imagine you guys get tired of us LEO's guys asking about our free HMMWV's. The really sad part is that while we were picking up our M1097 we saw an up-armored variant that was about to be cut up for scrap because no LE Department wanted it or didn't show to pick it up. It had an @$200,000 cost tag on it. Still had the turret. What a waste.

 

[86humv]

No electric fuel pump.
Hmmwv oil sender is a 0-120- psi
There are some that look identical, but are 0-60 psi.
MS24539-1
I have some...pm me

 

[krazyk]

Tragic end to this story. Got the engine running just to hear plenty of bad engine noises. Drained the engine oil to check and saw plenty of metal shards on the drain plug magnet. Not tiny metal grains but actual shards of shredded, peeled ferrous metal. Just a guess but I would assume camshaft or cam follower failure. This M1097 will have to wait for awhile. Our choices are cannibalize, return, or get new engine from armory. Cant really complain when it was free anyway. Odd thing is the vehicle log book had plenty of entries about parts replaced, etc. but didn't say anything about engine being "fragged". Maybe the Spc/driver quietly turned this one in before Sgt. noticed.