Scat 1.25 problem

[damicotile]

I have a set of these rockers that I put on but they kept throwing off lash caps.
Someone said the valves were floating, so I took them off.
That was a year ago and I had went back to stock rockers.
I am putting new heads on, Tims stage 2's, and will be putting back on the Scat rockers.
Here's my problem. During the short time I had used those Scat's, about 500 miles, I noticed the side play shims would get eaten up.
I never noticed it until today that the rocker area where the shims ride is not a machined surface. It has the texture of the cast stippling you see on the rest of the rocker. Does that make sense?
So this surface is too rough for the shims to hold up too.

Can this surface be machined flat and smooth or do I just use a flat file and do my best?
What do you guys do?
_________________
'73 SB
82x94
W-120 w/ CB light weight lifters
Silicon bronze sleeves
Scat 1.25:1
CB H-Beams
Straight cuts
42x37 Steve Tims
44 IDF's
9.2:1
A-1 Sidewinder coated

__________________________________

[slalombuggy]

Looks like they missed machining the sides smooth. Yes you could file them flat yourself being VERY carefull to keep them square. Finish them on a piece of fine sandpaper on a sheet of glass to get a SMOOTH SHINEY finish and wassh them well. Make sure you have the rockers positioned correctly over the valve and shim them to .006 side play.

If the new heads have stainless valves, lash caps are NOT an option, they are needed or you'll mushroom the end of the valve, I have a buddies engine apart right now suffering from this are the "builder" never put them on.

brad

[vwracerdave]

I think I wuld be looking at getting another set of rockers. Maybe a different brand.
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK

[damicotile]

[jfats808]

Sell me the 1.25 set cheap. Everyone mentions problems with that particular set up. I have no problems with the sets I have. You need to properly set them up before use.
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2276 IDA's 86C 11-1 DD !
2017 48 Trijet DRLA's W125

[66brm]

You should be able to surface the rockers you have, using a piece of glass and a sheet of fine wet and dry (1000-1200) wet it down well and lap it till the casting/forging marks are gone. Have you got the rockers setup correctly, as in are the adjusters located on the valve tip correctly? Also what side play have you set them too? What pushrods are you running? Alloy needs 4-6 thou gap and chromoly should be set at a loose zero. If they are set right it should be impossible to have a lash cap fall out.
_________________
Aust. RHD 66 Type 1
Aust. RHD 57 Type 1 Oval

[modok]

[damicotile]

I contacted Brother Machine and they said that the rockers come that way, no side machining.
I may have been using too thin of a shim, .010 stacked.
Valve adjustment has always been done at TDC which I know now is not the way to do it as the lifter is already making contact with the ramp.
Knowing what I know now may just fix this problem I am having with these rockers.
I am having a hell of a time trying to locate .030" side shims.
Scats are .765" id, bigger than stock ones.
I am going to try to smooth out the side of the rockers a bit. I have a few different ways to do that.
I just gotta find the shims.
_________________
'73 SB
82x94
W-120 w/ CB light weight lifters
Silicon bronze sleeves
Scat 1.25:1
CB H-Beams
Straight cuts
42x37 Steve Tims
44 IDF's
9.2:1
A-1 Sidewinder coated

__________________________________

[mark tucker]

contact scat poop.see what they do do.make sure there set up corectly.all of my scat rockers are machined,but the rocker blocks wernt.
and the way you ajust the valves is why you were droping caps. do it corectly and there should be no problem and it might stop beating the shims also.

[slalombuggy]

" I contacted Brother Machine and they said that the rockers come that way, no side machining."

Are all the rockers rough or just that one, if it's just the one I'm thinking your being fed a load of horse pucks. My Scat ones are nice and shiny like they've been machined. they have to be it's a contact surface. hhhmmmmmm..................

Check CB's site for shims.

brad

[damicotile]

No, they're all that way. For the kind of money they cost you'd think they would be machined, right?
I'll just file them up a bit, block sand them.
At least they'll be smoother than the way they are now.
_________________
'73 SB
82x94
W-120 w/ CB light weight lifters
Silicon bronze sleeves
Scat 1.25:1
CB H-Beams
Straight cuts
42x37 Steve Tims
44 IDF's
9.2:1
A-1 Sidewinder coated

__________________________________

[mark tucker]

do they have the name scat on each rocker??

[damicotile]

[tencentlife]

[damicotile]

I've got that link to Dan's site too but the problem is the Scat rocker shafts are a bigger diameter than the stock ones @ .765" compared to the .708" for the stock shafts.
I've got Steve Tims getting me some shims and he will ship them with the new heads.
All I have been able to get were .015 and .030 and when I mic'd them they were .017 and .033 after a deburring.
I'm either too tight or too loose. Go too thin and they just get chewed up.
Maybe with the new heads those clearances will change and allow me to set them right on. As it stands now with the limited selection of shims out there I can only do what I can to get then as close as possible.
I've tried like hell to find shim like the ones that go under valve springs but have had no luck, even from machine shops who just look at me like I'm so kind of dweeb. Maybe it's the language barrier, IDK.
_________________
'73 SB
82x94
W-120 w/ CB light weight lifters
Silicon bronze sleeves
Scat 1.25:1
CB H-Beams
Straight cuts
42x37 Steve Tims
44 IDF's
9.2:1
A-1 Sidewinder coated

__________________________________

[mharney]

The whole shim pack thing is so stupid, and I will never understand why they don't come in smaller thicknesses. What I do is put thin ones BETWEEN thicker ones to behave like a torrington bearing, and the thin ones don't get damaged that way.

I order thin ones from McMaster Carr.. they are not the perfect ID, but they are close enough to do the job.

[modok]

I have a whole rack of VSI brand valve spring shims.
I will look to see which numbers are 3/4" ID if you want

[damicotile]

Well I "machined" my rockers with a mill file and got all the casting bumps, for lack of a better name, smoothed out and then wire wheel'ed them to remove all the file marks.
Put them back together with the best shims I could find in my tool box and started it up.
Quiet for now at least. I'll drive it all this week and then take it apart and check them out.
I'll check out McMasters. I keep forgetting about them.

The wife say's "You're laying under that car more than you're laying under me."
She's got a point there you know.
_________________
'73 SB
82x94
W-120 w/ CB light weight lifters
Silicon bronze sleeves
Scat 1.25:1
CB H-Beams
Straight cuts
42x37 Steve Tims
44 IDF's
9.2:1
A-1 Sidewinder coated

__________________________________

[mharney]

[slalombuggy]

Mine just says "At least I know where you are!" You got it GOOOODDD, quit laying under the car

You could always sand an extra .003 off the rockers

brad