replaced wiped cam now I think I have a rod knock

[87SFI]

I think I have a rod knock after a wiped cam nightmare and now I put a roller in it. The knock I hear is very slight. You have to listen closely to notice it. Also, it is only apparent when the car is running hot. Do I have to pull the motor and rebuild it again or can I just replace the main and rod bearings while the motor is still in the car. Any suggestions?

Thanks
George

 

[ITSAV6]

welcome

Same here. Rod knock showed up after wiped lobe. Replaced rod and mains but rod started again. Pulling engine now and doing billet caps,forged pistons and balancing.

 

[Rickracer]

The metal ground off the cam had to go somewhere....

....New rod and main bearings would be a band-aid on a bullet wound. It's likely that the cam bearings are hurt too.

 

[87SFI]

oh man this really sucks! ok then looks like I have to pull the motor again!


Thanks guys

 

[snodgrass]

Pull the pan and check out what things look like down there. Not to take away from the other guys that posted, but my friend's GN wiped the bearings after a head gasket failure, and we installed a set of rods and mains from under the car, and it's been running over 20,000 miles since with plenty off beating. If the crank measures within spec, there is no need to pull the motor. It depends on how bad it's hurt. If it only knocks when hot, chances are it's not hurt too bad. They also make .001 under bearings if needed. Good Luck, Jeff

 

[87SFI]

Thanks jeff, I'd rather pull the pan and check things out first before pulling the motor. sounds worth a try.

 

[NC87GN]

If you are pulling the motor and dissassembling, resize all the rods. I bought an 87 gn motor with 50K with all stock components and did a mistake by just doing a standard rebuild with no blueprint. Come to find out after 400 miles most of the rod bearings were chewed down to the brass. Come to find out after inspection all the rods were out of round causing the premature bearing failure.

Mike Banas
87 GN