belt broke causing issues including low oil pressure

[1997 6.5 turbo diesel]

hello I am new to this forum and sorry if this has been asked before.

I recently bought a 1997 gmc 3500 2wd dually with the 6.5 turbo diesel. truck has 153,000 miles on it and ran and drove perfect the only issue i had was the belt was squealing. I had some belt conditioner and used that instead of replacing the belt, was planning on replacing the belt but have only had the truck for about 3 weeks now. anyways the belt broke and now I am having all kinds of issues

ok so the belt broke on the way to work the other morning. I heard it flopping around and pulled over. the belt pretty much split in 2 and still had about half of the belt still operating everything. i was only about 2 miles from my house so i drove slowly back to my driveway. when i pulled into my parking spot before i could get the truck into park it died.

I took another vehicle to work and when i came home to check out the damage i found that when the serpentine belt split, it tore the oil line in half that goes to the cooler draining all of my oil.

I replaced the oil cooler line and serpentine belt and filled it back up with oil.
I had to jump the batteries to get it to start, im assuming the reason it died was because the little bit of belt that was still connected wasnt turning the alternator enough and drained the batteries. It took a few tries but then the truck fired up and idled a little rough for about a minute and then seamed fine. I took it on a test drive and after a mile or so when it was warmed up it started losing oil pressure and dropped to zero and started knocking slightly. i got back to the house and shut it off.

I ended up changing the oil pressure switch/sender, found it to be almost broke in half once i got to it, had to pull the intake manifold off to get to it.
Also the intake manifold had oil in it.

after putting it all back together the truck still has like zero pressure on the gauge and is idleing rough and smoking, I did not take it on a test drive this time because i dont want to break something else.

do you think that the oil pump is bad. do i need to drop the transmition and rip open the oil pan and change out the pump or could it be something else that i should try first.

I changed the oil and oil filter about a week before this all happened, and had to fill it with fresh oil again after the oil hose broke. do i need to change the oil filter again? i have read that a clogged oil filter could cause these low pressure issues. also with oil in the intake does that mean the cdr valve needs to be replaced?

not real sure where to go from here

[arveetek]

I took another vehicle to work and when i came home to check out the damage i found that when the serpentine belt split, it tore the oil line in half that goes to the cooler draining all of my oil.

Unfortunately, it sounds like you ran the engine with no oil for a period of time. This has probably caused significant internal engine damage. Sorry to be the bearer of bad news, but your symptoms point to damaged bearings and possibly scored cylinder walls. :(

I would venture to say at this point that dropping the oil pan and inspecting the bearings would be the next step.

Casey

[DmaxMaverick]

Welcome aboard!

I concur with Casey. No good news here.

The oil pump and filter may be bad, but replacing them now won't fix what's broke. Running with low/no oil will kill the engine very quickly. While I doubt you'll find cylinder scoring, the main, rod and cam bearings have likely suffered permanent damage. If it wasn't ran much and not overheated, the engine is likely rebuildable, but you'll have to get inside for a look. The engine needs to be out and on a stand for a close inspection. If you're doing the work yourself, it's not likely to be too costly to bring it back to health.

[Robyn]

Yank it out..

That's about 3-4 hours to get it on a stand....

Do not waste your time trying to get into it in the truck....

I agree with Maverick....

[1997 6.5 turbo diesel]

thanks for the help guys. I talked with my father inlaw and he came and listened/looked at it and he thinks its rod bearing as well. he said to drop the oil pan and you would be able to see if that is the problem. is that right will i be able to tell if it is that by removing the oil pan

[DmaxMaverick]

Sometimes. Most of the time you'll have to remove some rod and/or main caps to see it. Start at the front. Either way, they all have to come off, sooner or later. You'll likely also have some cam bearing damage. If it's a 4x4, it's just as easy to pull the engine as dropping the pan.

[Robyn]

I agree.

Getting the pan off is a pain in the GMT400 trucks

The engine is going to need to come out anyway, so might as well get it out and then you can see whats going on much easier.

You can't fix it in the truck regardless...

[1997 6.5 turbo diesel]

I pulled the pan and changed the rod bearings but still alot of knocking and low oil pressure think the crank is bad it had some pretty good grooves in it where two of the bearings were pretty bad. so im looking for a new engine. what years will have compatible parts/engines. google isnt very helpful. I found a 94 with a bad transmission can i just swap my tranny into the 94 and then have my 97 for a parts truck for the 94?

[a5150nut]

If you didn't get it hot why not rebuild the one you have instead of taking a chance on an unknown motor?

[1997 6.5 turbo diesel]

If you didn't get it hot why not rebuild the one you have instead of taking a chance on an unknown motor?

thats what I initially wanted to do but after looking up parts and then talking to my father in-law i thought it would make sense to swap. where would you buy a rebuild kit. everything im seeing online is between 700-900 for a full rebuild kit and then cranks are looking to be 400-500 or so so i figured low end with those numbers is 1100. and the 94 i was thinking of buying the guys initially asking 1500. I was thinking if its a good running motor then for the same price of rebuilding i could have a whole other parts truck. not real sure what i should do