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Hey guys.
My mom has a 89 dodge dakota with a lower end knock.She had the engine rebuilt a few years ago.The man who built it told her to bring it back after 500miles so he could go back threw it and check everything.
Well she didn – She drove it 800miles and it started kocking and had no oil psi so she parked it. (She tryed to get back in contact with the man who rebuilt it but she could find him)
Well she parked it for 3 years. she was gona junk it but i offered her what she had in it 1800 for the rebuild.
I was gona rebuild it for my self but now im just gona rebuild it and give it to my brother for competing school.Its got a 3.9 v6.
I pulled the engine today and coulden get the torque convertor bolts off soo i pulled the engine with the torque convertor steal on the engine… When i got the motor out i was checking everything and found the torque convertor and a 1 to 1 1/2 play to it (The bolts wear lose) I literally unscrewed them by hand.
I started thinking this could have been the knocking.
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You mean if you rebuilt the engine again? If the oil was contaminated for too long with the assembly lube or whatever caused it to fail and somehow cause a no oil pressure condition, the cylinder walls are likely to have been damaged as well. Here’s Eric’s newest vid, conveniently on new/rebuilt engine break in. It’s like he read yer mind!
http://www.youtube.com/watch?v=tBD-rFP7 … AAAAAAAaAA
If you gave $1800 for it, I feel for you man. But I’m pretty sure we’ve been down this road before. It would be seriously hard to replace a crank without pulling the pistons, because the likelihood of having a connecting rod nick or otherwise damage the crank is pretty high as you are trying to fish it in there. Good luck.
I did a compression check on it before i pulled it. 125 per cylender.
The truck did start right up today. with the same problems.
just tell me what to look for when replace the rod bearings and mainbearings plz. If i did see anything bad, Im putting a crank kit in it.
My brother has to have a truck in 3 weaks. He starts a job in north Dakota as a weld.
Well, if it’s a definite knock from the bottom end, it should be pretty evident when you pull the main/rod caps. There will be damage to the bearings and/or the crank journals. Look for obvious heat marks/discoloration, etc. I would also add again to check for oil pressure with a mechanical oil pressure gauge, but I’m guessing if you had none, the thing wouldn’t run long. Did you already change the oil?
Also, if the engine was rebuilt, there is a good chance the crank was turned, and there are oversized bearings in the thing. That’s alot of work to consider without having the original rebuilder from 3 years ago to pick his brain. Are you sure it’s a bottom end knock? It just seems odd that going a few hundred miles over on the rebuilt oil-change interval would cause a serious knock. Did you tighten the torque converter bolts? The fact that they were finger tight leads me to believe the job wasn’t done terribly well in the first place, and you might be in for more than ‘swapping in a crank’.
Ill post a video tomarrow of the lower end with the pan off.
I did drop the oil – it was really black and kinda looked like it had flacks of metal in it.
Beefy thanks for your advise bro. God if it wasnt raining id go pull the pan now!!!I think if you had no oil pressure and developed a knock, you now have a really really big paperweight man. I suppose you could reassemble it and change the oil, and then put a mechanical oil pressure guage on it, but start by draining the oil and seeing what’s in it.
Start with the bottom end removal and inspection.A no oil condition is a no good condition. keep us posted on what you find. C8-)
If you decide to strip it down, i would look for FSM specifications and invest in some plasti-gauge to start checking clearances.
Good luck with your decision.
You mean your oil looked like this?
http://www.youtube.com/watch?v=ien1V1qG1yc
Not a good sign for the bearings. But at least you know going into it. Let us know what you find – maybe post up some pics.
Quoted From johnzcarz:
You mean your oil looked like this?
http://www.youtube.com/watch?v=ien1V1qG1yc
Not a good sign for the bearings. But at least you know going into it. Let us know what you find – maybe post up some pics.
I have seen this before too on a newly rebuilt motor on a 302 Mustang. Almost made me cry. I felt so bad for the owner.
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