Straub Trunnion Upgrade - some tight?
#1
Straub Trunnion Upgrade - some tight?
I installed the straub trunion upgrade in my 04 rockers yesterday. About half are loose enough that I can rotate the shaft with my fingers. The other half are so tight that I have to stick a screwdriver or awl in the bolt hole to rotate them.
Anybody else experience this? Are the ones that I can move with my fingers too loose or are the ones I need a tool to move too tight? I'm kind of concerned the clearances on the tight ones that might be so tight it messes up lubrication. I did use the included break-in lube during installation.
I found on another forum that there were some suspected inconsistencies with GM's (or their vendor) manufacturing of the rocker arm and they should be honed true but haven't seen that mentioned here (and there seems to be a lot of install experience here)
I'm tempted to call Straub and buy some more bushings to redo the tight ones but wanted to get some opinions here.
Anybody else experience this? Are the ones that I can move with my fingers too loose or are the ones I need a tool to move too tight? I'm kind of concerned the clearances on the tight ones that might be so tight it messes up lubrication. I did use the included break-in lube during installation.
I found on another forum that there were some suspected inconsistencies with GM's (or their vendor) manufacturing of the rocker arm and they should be honed true but haven't seen that mentioned here (and there seems to be a lot of install experience here)
I'm tempted to call Straub and buy some more bushings to redo the tight ones but wanted to get some opinions here.
Last edited by NC_John; 03-20-2017 at 07:47 AM.
#2
TECH Junkie
I had the same thing with comp trunnions. I just gave the tight bearing rockers a very slight tap as you would to push the bearing out of the rocker and they spun freely
#3
Super Hulk Smash
iTrader: (7)
They are pushed in too far. They should rotate freely if you hold it by the trunnion. What I mean is, if you rotate the rocker up holding it by only the trunnion, the weight of the nose of the rocker should always point down. It should be that easy to rotate. If not, it'll clearance itself over time...
#4
Thanks guys - that makes sense. I pressed the bronze bushings in a tad too far and they are too tight on the shoulders of the trunnion. I might see if I can give one a gentle tap to clearance it. I have got so much money going into this engine I want to make sure everything is right on it.
#6
Never countersink them... They should be flush with the sides of the rocker arm body and use plenty of assembly lube on the trunnions/bearings and also on the push-rod tips/rocker arm cups and valve tips.