Straub Bushing Trunion Kits?
05-13-2016, 02:25 PM
#224
TECH Senior Member
The OE rockers are a different arrangement... the needles/rollers do not run on the trunion, they run in between inner/outer hardened sleeve pair (i.e. inner sleeve is pressed on trunion, outer sleeve is pressed in rocker body)...
so if you're looking for trunion damage, it would show up on the running surfaces of the inner/outer sleeves, these are made from hardened steel stampings, so they will not show any wear.
so if you're looking for trunion damage, it would show up on the running surfaces of the inner/outer sleeves, these are made from hardened steel stampings, so they will not show any wear.
05-13-2016, 02:26 PM
#225
TECH Senior Member
I surmise that the Comp trunions are not heat treated properly, I will test this when I get home (see if a file cuts the running surface, if the heat treatment is correct then it should not).
Also note that the OE needle/rollers are bigger than those in the Comp kit (bigger radius roller spreads load out a bit more).
Also note that the OE needle/rollers are bigger than those in the Comp kit (bigger radius roller spreads load out a bit more).
05-13-2016, 04:50 PM
#226
I never liked the comp style trunion. Why I am still rocking the stockers. I liked the CME or something bronzed bushing upgraded ones but were to much money and mite as well go aftermarket. These look great and should be installing a set in my buddy's rockers this weekend.
05-14-2016, 08:22 AM
#227
I surmise that the Comp trunions are not heat treated properly, I will test this when I get home (see if a file cuts the running surface, if the heat treatment is correct then it should not).
Also note that the OE needle/rollers are bigger than those in the Comp kit (bigger radius roller spreads load out a bit more).
Also note that the OE needle/rollers are bigger than those in the Comp kit (bigger radius roller spreads load out a bit more).
I can have the material checked for hardness and run a metal analyzer on the material next week. It will tell you everything. My guess is it is something close to 4140 and about 50 Rc. They should be 52100 bearing steel and about 60 Rc, but that would double the price.
05-14-2016, 08:36 AM
#228
Installed the Straub set lastnight, waited until this am to crank the Corvette.
Horrible squealing noise when it first fired off. The noise has now deminished. I will be changing oil and filter later today for safe sake.
As far as valve train noise goes, there's no noticeable difference.
Horrible squealing noise when it first fired off. The noise has now deminished. I will be changing oil and filter later today for safe sake.
As far as valve train noise goes, there's no noticeable difference.
05-14-2016, 09:19 AM
#229
I had a squealing when I first started mine also. And I had soaked it in oil prior,also cranked the engine over a few times to build oil pressure before having it fire up. The noise did go away after building some heat into the valvetrain. I plan on changing the oil after breaking in my clutch and going to a quality 10w30 and see if that helps. Valavetrain noise seems about the same otherwise imo...but then again my car is rather loud regardless.
05-14-2016, 12:15 PM
#230
Installed the Straub set lastnight, waited until this am to crank the Corvette.
Horrible squealing noise when it first fired off. The noise has now deminished. I will be changing oil and filter later today for safe sake.
As far as valve train noise goes, there's no noticeable difference.
Horrible squealing noise when it first fired off. The noise has now deminished. I will be changing oil and filter later today for safe sake.
As far as valve train noise goes, there's no noticeable difference.
My fears confirmed......changed the oil and found micron particulates in the oil and filter. Not sure if the pictures will show in detail.
Change your oil after start up.
I allowed the bushings and trunions to soak in zinc additive overnight on Thursday, assembled on Friday afternoon. Once the assembly was completed I placed all rockers and bolts in a tub of mobil 1 oil until around 8:00pm last night and then installed.
This morning I cranked the car.
Pictures attached after ten minutes of run time.
This was my primary concern and why I asked the question initially.
Just wanted to add this oil pictured had less than 550 miles of use. Mobil 1 10w30 Gold Cap synthetic. So the color of the oil should show why I'm concerned. This is a 2006 Corvette with 22k miles.
Last edited by brobinson216; 05-14-2016 at 12:34 PM.
05-14-2016, 12:48 PM
#233
Thats quite a color change in oil though which leads me to believe alot more is at play there. Judging from the oil on my dipstick its still perfect and no shinybits that i can see. But I think you just convinced me to doing a quick change anyways!
05-14-2016, 12:54 PM
#234
Nothing else is going on here, it's a 20k mile garage queen with a cam, converter, intake, exhaust.
Matter of fact just for reference here are the rockers removed from the motor lastnight
05-14-2016, 02:19 PM
#235
TECH Senior Member
Straub Bushing Trunion Kits? I surmise that the Comp trunions are not heat treated properly, I will test this when I get home (see if a file cuts the running surface, if the heat treatment is correct then it should not).
Also note that the OE needle/rollers are bigger than those in the Comp kit (bigger radius roller spreads load out a bit more).
Also note that the OE needle/rollers are bigger than those in the Comp kit (bigger radius roller spreads load out a bit more).
There is a lot more to this than just the heat treating. I bought a set from Summit and the surface finish where the bearing rides was pathetic. We checked it on a Profilometer and in was around 20 Ra. It should be around 8-10 Ra. With that bad of a finish (it was not even ground), it will not take long for the rollers to pick up material and destroy the rollers, which looks like the issue with the pictures above.
I can have the material checked for hardness and run a metal analyzer on the material next week. It will tell you everything. My guess is it is something close to 4140 and about 50 Rc. They should be 52100 bearing steel and about 60 Rc, but that would double the price.
I can have the material checked for hardness and run a metal analyzer on the material next week. It will tell you everything. My guess is it is something close to 4140 and about 50 Rc. They should be 52100 bearing steel and about 60 Rc, but that would double the price.
Last edited by joecar; 05-14-2016 at 05:11 PM.
05-14-2016, 02:44 PM
#236
Teching In
iTrader: (2)
Join Date: Nov 2015
Location: Albuquerque NM
Posts: 43
Likes: 0
Received 0 Likes
on
0 Posts
Just happen to have a ME for a son that is a automotive ME at NMSU. He is going to look over this thread, and asked me if anyone would be willing to donate a few faded examples to run through his lab.
05-14-2016, 02:59 PM
#237
ME here. Like I stated earlier I sent 2 trunions from a low mile previous project to a well known lab for analysis. As far as RA finish of 20 goes on the bearing surface, one must remember RA shows average peaks and valley's.
I had .0006" - .00085" press between used rocker bores and bushing OD. Which is sufficient for this application.
These were measured on a microview cnc vision system, backed up with a master calibration set of disc micrometers.
I had .0006" - .00085" press between used rocker bores and bushing OD. Which is sufficient for this application.
These were measured on a microview cnc vision system, backed up with a master calibration set of disc micrometers.
05-14-2016, 03:25 PM
#238
Jon
This is the oil that was drained from my engine this morning after installing the Straub bushing trunions. Ten minutes of runtime. The sun makes the oil appear worse than what it is. But if you can zoom in on the photos the small particles can be seen throughout the drained oil.
This is the oil that was drained from my engine this morning after installing the Straub bushing trunions. Ten minutes of runtime. The sun makes the oil appear worse than what it is. But if you can zoom in on the photos the small particles can be seen throughout the drained oil.
05-14-2016, 04:40 PM
#239
Jon
This is the oil that was drained from my engine this morning after installing the Straub bushing trunions. Ten minutes of runtime. The sun makes the oil appear worse than what it is. But if you can zoom in on the photos the small particles can be seen throughout the drained oil.
This is the oil that was drained from my engine this morning after installing the Straub bushing trunions. Ten minutes of runtime. The sun makes the oil appear worse than what it is. But if you can zoom in on the photos the small particles can be seen throughout the drained oil.