Hi, I've purchased a 91 pickup to be my Daughters first ride,I got it cheap because the engine has a knocking noise that presents itself around 2800 rpm ,looking through some forums I've read a good trouble shooting technique is to pull a plug wire one at a time with engine running ,when I remove the #3 wire the noise stops. I'm thinking it's the rod bearing??? the motor has 150,000 miles on it runs strong and has passed California smog test. I would like to try and get some more miles out of it before complete motor overhaul. So my questions for you 22re experts is #1 Do you believe it's the rod bearing?#2 Should I try to change it without pulling motor? It is 2 Wd I believe I can drop the oil pan fairly easily , thanks for any input Darren

 

1. Yes its either the rod bearing or the wrist pin on the piston, more likly the rod bearing though.

2. As a temp fix you can replace the bearing depending on how bad the crank surface is. This will only hold up for 5-to 10 k miles or so.

 

Ok thank you one last question it's going to be a pain to do this bearing in place it being only a temp. Solution should I bother changing all the rod bearings if the #3 crank looks ok and new bearing tests ok with plastic gauge?

 

Very little more work to change them all.
Might improve oil pressure a bit too.

 

Okay thanks for your help. My daughter and I are going to take this on this saturday in the driveway. Although im worried I asked her to call the parts store and order the rod bearings, oil pan gasket, and check to see if they kept plastie gauge in stock. The lady asked Heather if she wanted either blue, red, green, or yellow plastie gauges and Heather said, "Well my truck is blue, im sure we want blue."

 

l0hn.

 

I have the same rod bearing issue on my pickup, why do you say it's a temporary fix to replace rod bearings?

 

Replacing the bearings without getting the crankshaft and connecting rod machined is a crap shoot may work fine for a bunch of mile or could go out really fast.