Torque specification

[GaryC]

My manuals do not state what the torque specification is for the steering box cover bolts on my '63. I have manual steering and its the three bolts above the worm gear. For the size and purpose of these bolts I would assume that I could just tighten them but, I would prefer to torque them to a spec.

Thanks!

[Duke W.]

Re: Torque specification

My '63 shop manual is silent on that too, but I have a side cover bolt torque spec from my '76 Vega/Monza supplement of 18 ft-lbs for the small Vega box and 30 ft-lbs for the Monza power steering box which is about the same size housing as our Corvettes. Noticed that the '63 shop manual and '63 AIM also fail to list a pitman nut torque. It's 165-185 ft-lbs for the Monza V-8 box. Maybe someone can come up with exact specs from a later shop manual or AIM.

Duke

[Tom B.]

Re: Torque specification

GaryC, and Duke,

If you're talking about the steering gear (box) mounting bolts, then the Service Manuals I have for 66, 67, and 68 show them to be 30 ft/lbs. Not sure if you're talking about the three bolts for the "lid" (Check Lube), which aren't shown but would think they would be no more than about 20 ft/lbs. Just checking the Pitman shaft nut, 67 and 68 show 140 ft/lbs. In the 66 it's the "sector shaft nut" at 120 ft./lbs. TBarr #24014

[Jerry Clark]

Re: Torque specification

I have an original 68 vintage Chiltons total service manual that specifies 26 ft. lbs. for the cover bolts.

jerry

[Duke W.]

In official GMspeak...

the "lid" is called a "side cover", and I'm surprised we can't find a torque spec for the side cover bolts in our sixties vintage shop manuals. I think the manual box for the Corvette was essentially unchanged through '82, so maybe some guys with a seventies or eighties vintage manual can find a spec. I know when I rebuilt mine I very carefully set the worm bearing and total preload, but I don't know what torque spec I used for the side cover bolts.

Duke

[Tom B.]

Re: In official GMspeak...

Yeow! Don't call a ship a boat to the Captian. I'll try to stay more specific. But GM also calls those rascal-of-a-bolt (for the side cover) "screws". Maybe Jerry's already found it, and I can't seem to find anything yet in the GM stuff, but I'll keep checking. TBarr #24014

[Wayne M.]

Re: In official GMspeak...

Duke --- You got me checking all my manuals (= no torques for the steering gear side cover). Even went to gearbox rebuild articles in Corvette newstand magazines over the last 10 years ( = ditto). Strange, because the side cover bolts are a maintenance (lube check) item. Maybe we should just use the standard range for the bolt grade / thread size. It might even be lower for the aluminum covers of the C3 era.

[GaryC]

Re: Torque specification

Duke,

The the '63 Shop Manual does state the specification for the pitman arm. It is on page 9-3. The specification is 100 - 150 ft. lbs.

Thanks all for the inputs!

[Duke W.]

When all else fails

If reliable references fail to list a torque specification then the "standard torque table" for the grade/size is the only alternative and should provide satisfactory results. I've got one around here somewhere, and finding it is now on my "to do" list. A 3/8-16 grade 5 is a common automotive fastener and I think the charts lists something in the range of 25-35 ft-lbs. The 30 ft-lbs spec for the Monza with power steering is an aluminum side cover unit, but I believe the bolts (or are they "screws" in GMspeak) have integral washer heads to prevent galling the aluminum. A standard torque table from a reliable source (like SAE) would make for a useful page in The Restorer. Good eye on finding the pitman nut torque, Gary. They did a nice job hiding it down there on the bottom of page 9-3.

Duke