Need a pickle person for clutch ID

[Joliet Jake]

Hello All

Well I picked up a 73 400 my girl friend calls “the Pickle” It has had a few changes such as install of a walburo carburetor and what may be a clutch change.

The sled runs great but the belt binds up tight after you let off the throttle. If you push the belt down a little it allows enough slack you restart but after accelerating and the drive cluth closes upon release you have the belt bind tight again.

After checking belt size and center to center I found out that these sleds have two kinds of clutches a 780 drive with a matching 780 secondary and a 850 with matching secondary.
I have what looks like a 850 drive but I’m wondering if it might be a 780 secondary. Also as you can see from pictures the offset is about I/2 inch not the 9/32 that they call for.

Anyone know if this is the proper secondary?

[400brian]

To the best of my knowledge, that clutch was only used on models with a 440 engine, 500 and JDX8.
I'd have to do some digging in the manual to see if they ID the secondarys.

What does the ID tag on the engine indicate that it is?

It's certainly possible that the clutch or engine was swapped, and the original secondary left in. In that case the simplest thing would be to get the proper Salsbury clutch for it, or swap both out for Comet components. This was done as part of a product improvement program on the 500s and JDX8s. The 850 was not a long life unit.

[Matt]

If she thinks that looks like pickle, show her a Skiroule.

Right Brian? You're info sounds right. I don't know how you would ID the drivens either, if they were different.

[Joliet Jake]

You are correct as to the “stock applications” according to the books I looked at.
The engine is a 339 and stock to the frame and VIN.

The engine shows it was moved to either correct the offset or try and remedy the belt binding
My guess is that someone swapped out the drive to a 850 along with the carb ,seeking to emulate the JDX series’ or just took the drive off a 600 and didn’t realize the need to match it with the proper secondary

I probably should take apart the drive and check the calibration of the arms but I still don’t know the difference between the 780and 850 secondary.

[400brian]

I probably should take apart the drive and check the calibration of the arms but I still don’t know the difference between the 780and 850 secondary.

I think I have both secondarys. The 780 on a '72 400, and the 850 on a '73 X8. The clutches are very different , the differences in the secondarys are less obvious.

[HoosierDeereMan]

The '73 400 should be equipped with a Walbro WDA-32 carburetor. It will be stamped on the top of the carburetor mounting flange.

The '73 400 requires a belt 1-5/32 x 42-27/32". A 500, 600, or X8 running the clutch you show requires a 1-7/32 x 44-13/32"belt. Once you get the secondary identified your binding issues may be something as simple as the wrong belt.

Troy

[Joliet Jake]

First Thanks Brian and Troy for your help.

I suspect that the belt that came with it is to short {41 1/16) and like you two have said the drive on it is a 850. So I need to id the secondary and buy a new belt.

Troy is the belt for the JDX #M64550

Thanks guys

[joshua16]

the belt for my jdx4 special is m64550. and i hope you get that sled running before spring becaues my sled likes to you get the pictuer

[HoosierDeereMan]

Those were Dayco/Carlisle dimensions I listed. Joshua is correct!

The Dayco Max 2 number for the JDX8 is 1071.

Troy

[lwb140]

i need a pickle chick as my wife is tired of jdsleds

[Sprailfire340]

i need a pickle chick as my wife is tired of jdsleds

Does that mean she is not making the 9hr drive with you this weekend?

[lwb140]

doubtful

[Sprailfire340]

Sounds like bonus space so you can haul more parts home

[400brian]

I took a look at the two secondarys today, and this is what I found:

The driven from the '72 is off and easy to measure. It is 9.25" in dia.
The one on the '73 X8 is still installed, and harder to measure. It appears to be around 9.5" in dia.

Hope that helps.

[Joliet Jake]

Thank you Brian!
That is the exactly info I was looking for …………..sounds like I have the correct secondary as it measures 9 26/32.
Will install a new 1071 belt and adjust and shim the secondary.

I owe you one Brian!