Break in after valve job?

[rafterman191]

I just installed my heads after getting them back from the machine shp. I drove it around town a couple days, maybe 50 miles and kept it under 46 mph. Yesterday coming back from my grandmas house, I was going between 50-55 mph for abut 10 miles. When I finally slowed down,there is a loud knock coming from the block. Sounds bad. Did I not give it enough time to get broke in, or could wrongly adjusted valves be to blame?

 

[beater_k20]

did you change the cam? that's the only "break in" required. your rockers may just be out of adjustment.

 

[Hogback Fabrication]

Did you replace the rocker nuts? A loose rocker could be pretty loud. They need to be replaced every time the rockers are removed (they are jam nuts).

 

[rafterman191]

Did you replace the rocker nuts? A loose rocker could be pretty loud. They need to be replaced every time the rockers are removed (they are jam nuts).

No, I just reused the nuts. They aren't the type w/ locks, they are off of a '86. Very good points though that it could be rocker adjustment. Giving me hope.

 

[Hogback Fabrication]

The lock nuts wear out. They are only designed to be used once.

 

[4xcrazy]

The lock nuts wear out. They are only designed to be used once.

wow, i wonder why all the motors i have worked on are still running then

 

[Hogback Fabrication]

Its not so much that they are really one time use, they just become less effective after each removal/install. I reused mine and after having to pull the rockers a couple times (broken valve springs) the nuts started coming loose.

It could be his problem and it could be something worse.

 

[4xcrazy]

Well, yeah, i can understand if you remove them several times, alot of components wear out like that, but to say they are only meant to be used "once" It's not a bad idea at all to replace them, but you can use them again. Just don't get crazy with using them again and again and again and again,,,,,,,,

 

[rafterman191]

did you change the cam? that's the only "break in" required. your rockers may just be out of adjustment.

Update:

I readjusted the rocker arms. Didn't help. I am believing it is unrelated now (kinda unrelated). The noise almost souns like an exhaust leak, just to give you a noise to relate it to. It gets alot louder with the tranny engaged and during acceleration. Like combining the sound of an exhaust leak with a loud engine knock. Sucks whatever it is. Could it be a bell housing problem?

 

[Mad-Dog]

Sounds like your flexplate is cracked bro.....RnR

 

[rafterman191]

Sounds like your flexplate is cracked bro.....RnR

Interesting. Will do some digging.

 

[rafterman191]

Sounds like your flexplate is cracked bro.....RnR

Could this possibly accompany some tranny fluid leakage? As it seems I have suddenly found a good amount of it on the bottom of the tranny, pan etc.