Flathead clutch adjustment. Help.

What's the proper method of determining just how many turns outward you're supposed to turn these 3 adjusting screws on the clutch? I'm talking about the 3 bolts on the ends of the clutch throwout arms.

I'm installing a 47 trans on a 50 motor and the 50 has the same 3 bolts. Pictured is a 41 clutch, but the same clutch is on the 50.

Thanks,

Mike

 

The important thing is that they are at the same height. They would be set up with the cover bolted to a jig with a spacer plate to simulate the clutch disk and the screws would be set to a given height, all equal. If you put a straight edge across the bellhousing and measure the height of each one, just make sure thay are the same.
Mart.

 

Thanks. I pretty much figured the tops would all be level with each other. It seems like a pretty straightforward adjustment.

1- Set them all to the same amount of turns out, and make sure they're all level with each other.
2- Put the trans on and see how much free play there is before the throwout bearing hits the thowout forks.
3- If more or less play is needed remove trans and go back to #1.

I was just making sure there were no other gotchas that I should look out for.

Mike

 

Can I add; when everything is together; with the clutch pedal out, the adjustment screws should be just clear (not touching) of the throwout bearing. Also a good time to replace the throwout bearing return springs.

If they stay in contact, the bearing will wear out very quickly.

 

Here's a spec from the 1947 dated Ford trans and clutch manual. You'll have to extrapolate for your '50 9 1/2" since it didn't exist then...
From Ford: Bolt pressure plate to a good flywheel with a gauge plate between wheel and pressure plate. This is supposed to be .340 thick for 9", .295 for 10", and .365 for 11". I would ***ume you can just use your new disc here in place of the plate. Ford calls for levers blocked down with a chunk of wood during the bolting, then released--normal practice a**** mechanics would likely be just tightening the pressure plate down slowly while going from bolt to bolt across the thing to avoid bending the cover. Anyhow, once together, remove any hypothetical wood blocks, lay a straight edge across top of pressure plate cover at flat spring seat area, and measure to highest point on those adjusting screws: 11/16" for 9", 15/16" for 10", 7/8" for 11". I would ***ume there's a spec for the '49 type in the shop manual, but I don't have this late-model info...

 

Thanks for all the input, its really gonna help me this weekend. With 3 days of work, I hope to go from this:



Back to this:



With bigs and littles too.

Mike

 

I think the main point is to have the three contacts even. Then, unless you are up to something really strange, normal external adjustment should do the job.
Remember, Ford provided a nice little window under that tin cover so you can see what's happening. Parenthetically and too late for you, I've decided to paint the inside of the case in this area flat white to give a better view into this area on future trans rebuilds.

 

That is one sweet truck! I want one!

 

You're too late! Manyolcars has all the rest of them!

 

[ QUOTE ]
Pulling the motor to adjust freeplay sounds extreme. Couldn't you get it within an accepable range and adjust the freeplay at the clutch/pedal linkage? I thought that's what the threaded yoke was for? I'd hate to see you have to install and uninstall the motor three times to adjust the clutch.

[/ QUOTE ]

My motor goes in the truck this weekend. Since it and the trans are in my garage I can remove the trans easily if I need to adjust stuff. You are right though, that would **** if one had to do this with the trans and motor in car while peeping through that little window.

Nice thought on using flat white. I'll probably do that tomorrow.

Fellow HAMBers Jive-Bomber and Justinm may be helping me. I'll try and do***ent the steps of rebuilding the rear end, installing the open driveline conversion at the banjo, installing open driveline mounts for the radius rods (no more torque tube to mount to), and the engine install.

Mike

 

[ QUOTE ]
You're too late! Manyolcars has all the rest of them!

[/ QUOTE ]

Almost!
Here's my '41...
http://www.nesstronics.com

 

Nice one, Dave.

I need one. Gotta have a '40 to match my coupe One day...

 

Here it is 2025 and just now finding this post. This material was not covered in the shop manual. Thanks a million Bruce Lancaster. I hope you are still on the board.

My pressure plate was a little different than the one shown up top, but the circled nust allows adjustment.

 

Good to know, as I had never heard anyone mention this before. IIRC, Bruce had p***ed away some time ago.

 

If he is it is only because heaven has wifi. Bruce left us a while back but left a bit of his "librarian" intelligence for us to study and learn from. RIP Bruce

 

Here’s a closeup of your ‘49 - early ‘51 Mercury pressure plate, the nuts are staked to hold them in place once the finger heights are set at the pre-determined position.
The reason the shop manual does not touch on this is because you should not mess with them.
Clutch adjustment should be done at the linkage.

 

This is not necessarily true, especially with rebuilds. The last rebuilt I got for an 8BA had the fingers at three different levels, differing by almost .125". This clutch did not have the adjustment screws on the fingers, so I had to do it the hard way, by taking out those "intermediate" bolts and slipping shims under them. It was quite a job (you are working "blind" on a trial and error process), but I finally got them within .010". I don't absolutely know if it was really necessary, but this is the smoothest clutch I have had in a "shoebox".

The source of the rebuilt? Fort Wayne Clutch.

 

Long style pressure plates are not the same as Borg & Beck style. Your Long style clutch didn’t have the adjustment screws on the levers and that is common on rebuilt Long style pressure plates. Yes, shimming between the yoke and clutch cover would lower the finger or milling the yoke the finger pivots on would raise the lever, although milling would require complete dis***embly. If the fingers are adjusted to the same heights that will help with clutch release.
For the B&B clutch in the post by @kbgreen the fingers are held in place by what might be called eye bolts. The bolts slip into holes in the pp casting, a dowel goes into the eye and the lever pivots on the dowel with a stamped retainer holding everything on the disc casting. Those nuts on the top of the clutch cover are for adjusting the finger heights at ***embly, but you need to know the thickness of the clutch disc to set the height. Basically it’s set them (at the factory) and forget them.
I’m guessing about @kbgreen ’s issue but if the problem is not enough adjustment at the clutch linkage playing with finger heights on a B&B is not the way to go. Replace the clutch. BTW, my first full time job was on the ***embly line at Borg & Beck in Chicago.

 

I don't know what you just said, but what I did worked for me.

 

It was never mentioned that shimming the mounting yoke would not correct a couple of low fingers on a Long pp, the bolts are easily accessible and with trial and error it could be done.
The Merc pp noted in my comment is a different ballgame. The nuts on the pressure plate cover are much easier to adjust at the factory for proper finger height, you don’t need any perfectly matched components like for the Long pp. I was suggesting that the nuts are not there for any adjustment of the B&B in the field.

 

What is the spec for the B&B 10" finger heights? All I can find are the 9",10" and 11" long style. What thickness of plate as a gauge, or clutch disk thickness is used, and how far from the top to fingers?