'40 steering problem revisited

I'm more familiar with the f-1 boxes, but in a lot of applications you have to file the flats down. I just file all of them out so I can clock the arm anywhere you want.
 
I now have correct pitman arm and it goes on to sector shaft further but when turning right the tire hits the frame before 2 turns. The centers on the '37-'41 pitman arm are approx. 3/4" longer than the '36 pitman arm I was using. I get about 1 7/8 turn to the right, 2 1/4 to the left. Why don't I have the same problem turning both left and right?
 

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When you are turning are you starting with the steering wheel in the driving position.
What you want is steering wheel in center and wheels straight. If it drives ok use the car.
 
Not totally sure what the issue is with the new arm, but once again, that is the reason you file the pitman arm serrations, so you can clock the arm where you need it. But before doing anything you need to be sure your steering is centered. Disconnect the draglink and then turn the steering wheel stop to stop and determine the center position. Now look at the pitman arm and see where it is pointing. If it is in the correct position then adjust the draglink to fit with the wheels pointed straight ahead. If not you may need to file the pitman arm serrations so you can re-clock it.

Also, there should be stops on your axle that stop the spindle from turning before the tire contacts the frame.
 
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agree with JSeery in that you should have a nut on the spindle locking pin that acts as a steering stop so your tires should never hit the frame.
 
The new pitman arm has already had the serrations removed that JSeery speaks of but the there is no taper in the end of the arm for the tie rod end to fit in but it still seems to work.

As for the locking pins, I reversed them with the nuts facing forward, so that I could get more travel when the '36 pitman arm was being used, went from 1 3/4 turns lock to lock to very close to 2 1/4 turns lock to lock.

Please offer opinion as to why tire contacts frame "only" when I make a right turn, plenty of clearance when turning left. I have removed material from one end of adjusting sleeve on the the drag link rather than an equal amount from both ends, could that be the problem, I don't see it but maybe? If I get a shorter drag link (CHASSIS ENGINEERING) would this make the wheels turn less in either direction?

I tried re-clocking what I think is one tooth over and the steering wheel would turn further to the right before the tire made contact with the frame; couldn't re-clock further because drag link is too long and have turned the adjusting sleeve as far as it will go.
 
It's appears to be a clocking issue and you will need a shorter draglink. The end of the pitman arm has to have a tapper for the tie-rod end. If it is an original part and doesn't have the tapper it may have been drilled out for a bolt. This is often done with the use of the heim type ends. If so, it will not work in this application (unless you switch over to a heim-end).
 

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I will use pretty words. I believe you have the worm from the 36 still in box.
Drag links have tapers and you have the wrong pitman arm.
You don't need to file they are made for no thinking.
36 turn to far 37 to 48 turns 3 1/2 turns.
I used my pretty words so listen.
 
I live in Kansas! You must be kidding! Although we are have a cool summer, been in the low 80s for two weeks, back into the 90s today. A normal summer is 105 to 110. The big difference is we can have fairly high humidity with it, that is the killer. Lived in El Paso for a while, piece of cake compared to Kansas in the summer.
 
If you have the drag link removed, try turning lock to lock.
You say 1 7/8 plus 2 1/4 that's 4 1/8 is this true or not.
With a 36 worm that's what you get.
37 to 48 will only turn 3 1/2 turns.
36 17to1 turns 87 degs
37 48 16to1 turns 78 degs
So you are turning 10degs more then needed.
The only way to get keyway 6 or 12 o'clock is turn the shaft splines on the shaft to worm. We can think clearer in the cooler weather. LOL
 
I really hope that whomever sold you that "roached-out" Pitman arm wasn't one of the folks that I suggested for you. You need to send it back to the guy with clear instructions where he should "INSERT it SIDEWAYS"!

Nevertheless, a '40 box with a '40 Pitman arm in a '36 has been done too many times before now.......it WORKS! The frame dimensions are essentially the same as a '40. Distances are similar. One thing that everyone is forgetting is the interference you HAD with the king pin LOCK PINS when inserted in the NORMAL direction with the spindle stop NUTS on REAR side of axle because of the disc brake calipers.

As NEAL in CA stated, "the ACORN NUTS must limit the spindle movement-NOT the steering box internals"! As MART attempted to explain earlier, turning the lock pins around (with the acorn nuts on FRONT side of axle) is not the same as NORMAL. This is most-likely why you have gained more turns lock to lock. And this is also where the ACKERMAN theory comes into play. With the lock pins inserted normally, the spindle on the side MATCHING the direction of your turn (left spindle/left turn) is the spindle which contacts the acorn nut, acting as the STOP. That same spindle is ALWAYS the spindle located closest to the INSIDE of the turn (circle). As such, that spindle is ALWAYS turned TIGHTER (more degrees) than the opposite side spindle. ACKERMAN always turns the spindle on the INBOARD side of the turn to a greater angle than the spindle on the OUTBOARD side of the turn.

Now, with the lock pins and ACORN nuts on the FRONT side of the axle, the spindle that makes contact with the acorn nut is now on the opposite side of the vehicle. As in the case above where we were making a LEFT turn, and we NOW make a left turn with the acorn nuts on the FRONT side of axle, the LEFT spindle is NOT the spindle which will make contact with the acorn STOP NUTS......the RIGHT spindle will now contact the acorn stop nut. And what you must not forget is that in a LEFT-hand turn, the RIGHT spindle turns to a lesser degree than the left spindle (because it is on the OUTSIDE of the turn (Mr. ACKERMAN). So, the limiting spindle is now allowed to turn to a much greater (tighter) degree, allowing the left spindle to turn even tighter still. That is the main factor for your number of turns of the steering wheel being greater, lock to lock. This would also explain your tire hitting the frame rail......it's being allowed to turn to a greater degree than Henry designed for. In addition, the longer C to C distance between the holes on the '40 Pitman arm will also ADD to the degrees of turn to the spindle. So, I think George can finally quit insisting that your '40 steering box has the wrong worm gear. Or maybe not! DD
 
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Lets just answer the question 4 1/8 or 3 1/2 ,ackerman has nothing to do with it.
I can watch this go another 2 years as I did mine 2 years ago and tried to help.
If you can count to 5 do it.
 
George, the box is a '40, sold the '36 box before I got the '40 box. With the drag link disconnected I have 4 1/2 turns lock to lock.
 
Ok forget the turns. The sector only turns so far because of case. I think the problem is with the keyway not to your likening. Center to lock to lock. As I remember with my 39 I used 560x15 tire with 5" rims so would hit frame. The 37 to 40 pitman arm should get you able to drive with out problems. That should get you close with keyway. If not the splines on worm have to be indexed.
Another thing to watch out for is drag link will go on upside down nut down possible oil pan hitting.
 
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