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Scott
07-07-2006, 12:27 PM
I replaced the bellcrank in my '66 Crusier last year, but a couple months after it was done my steering got really squirrely and the car would feel a little out of control when I hit bumps. When I took it back to the shop, they found the cinch bolt for the steering arm hadn't been tightened properly, so they fixed it. Now, about 800 miles later it seems like I'm feeling the same thing happening.

My question is, is there a way to get that bolt to stay tight once and for all, if it is loose again? Has anyone encountered this?

Mike Sal
07-07-2006, 01:21 PM
If indeed this bolt has come loose again, and there is no contributing factors (shimmy or wobble that could shake it loose), the bolt may be failing (stretching or threads stripped). Replace the bolt.

Another possibility is something else has come loose. If the original mechanic didn't tighten the bell crank properly, maybe he left other things loose too. Have it all checked.
Mike Sal

JDP
07-07-2006, 01:45 PM
The torque spec on that bolt is much higher then you might expect. If they just used a rachet wrench to tighten it, it will come loose again.


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Scott
07-07-2006, 02:35 PM
JDP, where are the torque specs? In the shop manual it only says to "tighten securely."

Alan
07-07-2006, 02:43 PM
52-54 Lbs. Ft. and the nut is a special one that is slightly out of shape so it stays put but if you remove it a few times it won't hold that 3 cornered hat shape and will be just like any other nut.

Scott
07-07-2006, 02:45 PM
Thanks Alan. How'd you find the torque spec? Only 52 lbs? That's not much.

N8N
07-07-2006, 03:01 PM
my '56 FSM says 60-65 ft-lbs. and that is significantly more than normal for a 3/8" UNF bolt. The factory bolt is Grade 8 (hence the higher torque spec) so if it needs to be replaced or is missing it should be replaced with a Grade 8 fastener.

nate

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Scott
07-07-2006, 03:14 PM
In the chassis parts manual they don't show the bolt, but they reference a couple washers and describe them as "sh'prf". What's that mean? If they are missing could that also allow the nut to loosen up?

Also, it indicates the bolt and nut are 7/16". Maybe earlier cars were 3/8".

I'm still not positive it's the cinchbolt, but that's where I'll check first, since I had a problem there before.

Alan
07-07-2006, 04:05 PM
I was giving you the specs on my 53 and it is 3/8" bolt and special nut. No washers.

Scott
07-07-2006, 04:26 PM
Where do you find the torque specs??

N8N
07-07-2006, 04:31 PM
"sh'prf" is shorthand for "shakeproof" i.e. a star washer.

I just looked at my late shop manual and it is indeed a 7/16" UNF bolt on those models, spec. is still 60-65 ft. lb. I seem to recall that the nut on these is a special nut, not a self locking one, but thicker than an ordinary nut.

Torque specs are in the shop manual, in the '56 manual it is in the back; in the late manual it is in the front, toward the end of section I.

nate

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Alan
07-07-2006, 09:07 PM
Scott, I dug out 3 more bellcrank pinch bolts and checked them 2 were off 53K's and 1 was off an Avanti. All were 3/8" X 24 X 2 3/4". The nut is 7/16" thick and has a machined raised spot on one end, the other end the last 2 or 3 threads are tweeked out of shape so the nut goes on easy up to the last few threads then you can feel some tightness. All 3 had split lock washers. The specs were from Motors Auto Repair Manual 1957. All of their torque specs are for 30 wt. motor oil. If you use no oil at all, dry threads, you would have to go higher on the torque. Now if you used ARP assembly lube you would have to go down to 35 lbs. So the best thing to do would be to mike the length of the bolt and after you torque it down make shure you have .006" or so bolt streatch.

Scott
07-07-2006, 09:38 PM
This is all great information! I did take it to the shop this evening. The mechanic hoisted it up and took the weight off the front tires and moved everything around quite thoroughly while I watched. He checked that cinch bolt and it was tight. It looks like the play is in and around the steering box. I don't think the innards are necessarily out of adjustment, but it did look like the movement was at leat partly due to a worn bushing where the little sideways steering output shaft comes out. Now I'm not sure if I should have the whole steering box replaced by a good used one or just get a new bushing and have them take out the unit and put in the new bushing. That might not even solve the problem. Yuck...this could be expensive.

PackardV8
07-07-2006, 09:46 PM
Did you replace the bellcrank forging itself or the pivot pin kit, or just the bearings?

If a bellcrank has been run for years and miles with the pinch/cinch bolt less than tight, it may have worn in an hourglass shape and no amount of torquing that little bolt will keep it tight. Doesn't take much wear to make a difference with all the leverage of the long arms. Power steering cars, oversize tires, or offset wheels all can put stress on that weak link.

thnx, jv.

PackardV8

PackardV8
07-07-2006, 09:50 PM
Did you replace the bellcrank forging itself or the pivot pin kit, or just the bearings?

If a bellcrank has been run for years and miles with the pinch/cinch bolt less than tight, it may have worn in an hourglass shape and no amount of torquing that little bolt will keep it tight. Doesn't take much wear to make a difference with all the leverage of the long arms. Power steering cars, oversize tires, or offset wheels all can put stress on that weak link.

thnx, jv.

PackardV8

Alan
07-07-2006, 11:42 PM
Scot, Are you talking about the steering box at the end of the column or the bellcrank tower that sits in the center of the front crossmember? If you are talking about the bell crank tower, remove the 4 bolts drop the tower out. Remove the large nut on the bottom and watch the shim washers. Sometimes after rebuilding the the tower you have to change the shim pack to get the thrust you want. If the pin is not badly worn you can press out the upper and lower Torrington B1612 bearings and put in a B1612OH in the center and a pair of B1616's upper and lower so you have some surface of the pin that has not been worn. If you do it your self it will be less than $20.

Scott
07-08-2006, 10:19 AM
I had replaced the bearings in the bellcrank tower, but did not replace the whole unit. It don't see any appreciable slop there.

In my earlier post I was referring to the steering box at the end of the steering column. That's where there appears to be play. I'm sure there was some before, but maybe the last 800 miles has finally got it to a point where I can really notice an effect on the sureness of the steering.[?]

This car has manual steering (but it has power disc brakes!).

Dwain G.
07-08-2006, 11:52 AM
quote:Originally posted by Scott

In the chassis parts manual they don't show the bolt, but they reference a couple washers and describe them as "sh'prf". What's that mean? If they are missing could that also allow the nut to loosen up?


"Shake Proof"

Dwain G.

N8N
07-08-2006, 12:19 PM
Scott,

there should be an adjustment for the endplay of the Pitman shaft in the steering box. Or do you mean that the shaft actually wobbles, like a bearing or bushing is loose?

good luck,

nate

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Scott
07-08-2006, 06:11 PM
Well, it I wasn't really paying attention to whether the shaft was moving in and out, but I dpn;t think it was. The only motion I seemed to see was sort of up and down, as though the bushing was worn.

I checked SI's catalog and the constiuent parts of the steering box a very expensive. Wouldn't it be easier to get a decent used unit that's loose (that is, not in a car) and just replace the whole thing, instead of tearing this apart and rebuilding it?

N8N
07-08-2006, 06:45 PM
Depends on if it's a Saginaw or Ross box. If it's a Saginaw I would replace the bushing and seal; if a Ross it might be best to search for a better unit, unless yours is in otherwise good shape. The Saginaw is a recirculating ball unit; similar to that used by BMW up until a few years ago. The Ross is a much cruder cam and lever affair that does tend to wear badly due to the much higher internal friction.

nate

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