Transmission knock or ???

I did some testing today:

1) Knock is noticeable only in 1st, 2nd, reverse and neutral at any time the clutch is released. Knock is a heavy knock (not a tinny knock) and seems as if someone is under the car hitting the frame or transmission with a large ball peen hammer. Knocks are about 4-6 per second in low gear depending on the speed of the car.

2) If coasting in neutral and clutch is released, the knocking is still there, but not as loud as when in first, second or reverse gear. Press in the clutch when in neutral or in any gear and knocking stops immediately

3) There is no knocking sound when car is in 3rd (high) gear with clutch released or not released.

Are NOS parts (gears and gaskets) available for this transmission and if so, where is a good source?

A better option might be for us to pull the transmission and send it to a qualified rebuilder who has experience with this transmission. Is there anyone that specializes in this type of work? (I am in NE Ohio). I prefer to stay with the original transmission due to the low miles on this car. Up until this past Thursday the transmission and clutch were perfect - as smooth as I have ever driven in a flathead V8. I am more interested in fixing it now than trying to figure out what happened, as the damage is done and I want to move on.

About how long should it take to pull the rear end assembly and transmission? Are there any special hints or concerns when doing this? In my younger days I always pulled the engine on my early flathead V8s, as didn't want to deal with the rear spring - this time I prefer to work from the back and not pull the engine, as we just finished a full tuneup and wiring replacement.

Any more ideas will be greatly appreciated. Thanks,

Fritz
 

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seems like there was a special place to put the jack stands in the rear to get the rear end to swing back far enough to clear the tube from the trans.
 
We're down in the Cincinnati area. You'd have to pull the trans and bring it in. We specialize in rebuilding these trannies. I do have quite a few NOS gears at the moment, but in any case we can handle it. If you want us to look at it, call the office Monday......Mac VP
 
Pull the ****** & send it Mac Van Pelt. Hell You may want to just deliver it just to meet Shelly. You are in Ohio & so is Macs' place.
Nice cars & garage I might add. Back in the day around Hartford ,Ohio I had a 48 vert with a race motor. The ****** was pulled every week for new cluster gear.The shift lever went almost straight up form speed shifting a lot of time WO the use of a clutch. Don't ask about rear axles & gears & axle keys.
Race saturday & sunday night & work under the old oak tree the rest of the week making repairs.
 

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Thanks much - once I figure out the exact source of the noise, I will pull the transmission and get it to Van Pelts. In the meantime, am still looking for suggestions as to what might have failed, based on my updated description of the problem in my last post.

Fritz
 
Here are the instructions for removing the rear axle and torque tube.

RearAxleRemoval.jpg


Of course, you don't have to remove the brake stuff just to get it out of the way to take the transmission out.

I like to remove the spring from the hangers and leave it attached to the frame. Seems easier and is less weight on the axle to man handle. Here's how I disconnect the spring from the hangers. (Reverse procedure to reconnect.)

I leave the axle hanging on the shock absorbers and lift the end of the spring with a bottle jack just enough to take the pressure off of the shackle bolts. Nuts can be removed before or after placing the bottle jack.

IMG_4009.jpg


Then remove the shackle from one side.

IMG_4010.jpg


Then the other side. (Spring end does not budge a bit - held by the bottle jack.)

IMG_4011.jpg


Lower the bottle jack and the spring slowly until it reaches it's limit of where it wants to bend to.

IMG_4012.jpg


Then move the bottle jack out of the way, put the floor jack under the differential, jack it up enough to take the pressure off of the shocks, remove them from the axle brackets, then the axle is floating on the floor jack to move up or down and roll backward to remove it with torque tube once everything is disconnected per the instructions above.
 
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seems like there was a special place to put the jack stands in the rear to get the rear end to swing back far enough to clear the tube from the trans.

I put the two jack stands under the frame just before it curves up and over the rear axle.
 
I did some testing today:
A better option might be for us to pull the transmission and send it to a qualified rebuilder who has experience with this transmission. Is there anyone that specializes in this type of work? (I am in NE Ohio). I prefer to stay with the original transmission due to the low miles on this car. Up until this past Thursday the transmission and clutch were perfect - as smooth as I have ever driven in a flathead V8. I am more interested in fixing it now than trying to figure out what happened, as the damage is done and I want to move on.
Fritz

Fritz... It's easy to figure out what happened. Someone badly screwed up your transmission and it has to come out.
Take it out and take it to Mac Van Pelt . He's the expert. He has the parts , and he's in your state. When you get it back, it will be good to go.
When it's back together again with the refurbished/rebuilt transmission, DON'T EVER LET ANYONE DRIVE YOUR CAR AGAIN!
 
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Re: Transmission knock UPDATE REPORT

TRANSMISSION REPORT

My mechanic pulled the transmission and there were two fresh broken teeth in the main cluster gear. Van Pelt sent his instruction book and talked to my mechanic and the new gear had been shipped to us and is ready to install. I am convinced that someone not familiar with older column shifts probably hit reverse instead of second. Each broken gear tooth was about 3/4" long and the break looked very fresh. Too bad some of the younger generation doesn't know much about how to shift a 3-speed transmission.

Fritz
 
Sooooo......now that it's fixed, I'm kinda guessing that lettin' me take it for a short spin would be out of the question? DD
 
I'd venture to say the guy tried a speed shift or burn out. It would have ground & very noisey trying to go in reverse. There is this option also: While moving backwards in reverse put ****** into 2nd then 1st & pop the clutch to do a burn out. Have done that a lot in the old model A back in the day. But my money is on the my first remarks. Been there & done that see my other post #26
 
Whatever happened did so at the garage. No coincidence. Have the transmission pulled and inspected, but not at that place!
 
While your at it you may as well pull the torque tube and have a good look at where the shaft & pinion spline meet, make sure that is not loose, or you will be having another clunking noise..
 
No more transmission knock.

The '47 Ford is back on the road and running and shifting great (no more knock). My mechanic pulled the transmission and it had two "newly chipped" teeth in the cluster gear. He contacted Van Pelt who had a NOS gear in stock and using the advice in Van Pelt's book and also with some help over the phone with Van Pelt, the car is like new now.

Thanks for all of the analysis and advice on this forum, which was right on. You can be sure that no one but me drives this car again. Many can drive a floor shift as they can see what they are doing, but a column shift is all by the feel and that feel comes from years of experience.

I am very much impressed with Van Pelt and lucky that they are also in Ohio and had the needed parts.

Fritz
 
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