Intermediate shaft troubles

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JoeSBP

JoeSBP

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Good evening folks, just had a few questions about intermediate shafts/gear for my little 340.
I recently purchased a new distributor (MSD) and it appears the distributor shaft and key are too large to fit into my drive gear. Upon close inspection, it's obvious the previous owner polished the old distributor down to fit. I pulled the intermediate shaft out for a close look, and found its galled in two places.
What would cause this galling? Installing the shaft by force on a new bushing that wasn't properly burnished?
If the bushing is shot, can it be replaced while still in the car using the specialty tool?
It appears to be a brass gear and hardened shaft, but it's a hydraulic roller cam, so thinking of going with the Hughes coated gear vs brass. Anyone have experience with it? Or other possible options? Are there different diameters available for the intermediate shaft?
As always, any and all input is appreciated

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The wear just under the drive gear looks normal to me. However the second lower wear mark,I have never seen that before.It should not be there. Since it seems to be on one side only, that would seem to indicates that it is bent. Bent is no good. To prove it is bent, roll the shaft on a glass table, a bent one will make an awful clacking noise.Plus it will roll funny.Throw it away.

Billet rollers require this type of gear. I wouldn't change it to stock-type, cuz this one appears to be wearing fine on the teeth.
Now that the shaft is out of the engine, will it accept the MSD?
 
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Won't accept the MSD, I even polished the gear internal to make sure it wasn't just a high spot, no dice.

It's a roller, but it's not billet
 
JoeSBP said:
Won't accept the MSD, I even polished the gear internal to make sure it wasn't just a high spot, no dice.

It's a roller, but it's not billet
Click to expand...

If it truly is a cast cam core then just use a cast intermediate gear or even stock. The one you have is bent and bad news from the looks of it. J.Rob
 
AJ/FormS said:
The wear just under the drive gear looks normal to me. However the second lower wear mark,I have never seen that before.It should not be there. Since it seems to be on one side only, that would seem to indicates that it is bent. Bent is no good. To prove it is bent, roll the shaft on a glass table, a bent one will make an awful clacking noise.Plus it will roll funny.Throw it away.

Billet rollers require this type of gear. I wouldn't change it to stock-type, cuz this one appears to be wearing fine on the teeth.
Now that the shaft is out of the engine, will it accept the MSD?
Click to expand...
hughs has a steel gear that will work on billet, got one in mine. I wouldn`t replace yours w/ a bronze gear. their gear will work on anything.
 
RAMM said:
If it truly is a cast cam core then just use a cast intermediate gear or even stock. The one you have is bent and bad news from the looks of it. J.Rob
Click to expand...

x2.
The 2nd mark lower on the shaft and the issues with the tab fitting the slot are the evidence. Toss it, get a new MP one. Some hydraulic rollers have cast gears on them. If you are not sure what the cam you have has for a gear, you can run the bronze, it's just expensive and designed to wear out instead of the camshaft.
The bushing can be replaced in the block. I made a tool that uses a slide hammer on a long carriage bolt to pull them. Some new bushings are made properly sized. Look for the Dorman version.
 
well I guess it's all pretty straightforward then. Replace shaft, gear, and bushing.
Anyone have the preferred PN or link for the intermediate shaft? I'm going to go with the Hughes coated gear, since it will work with anything.
Preferred vendor for the install/burnishing tool? I'm going to just use a small puller/slide hammer to yank it out
 
Buy the Dorman brand bushing and you don't need to burnish it. I think I got the last batch of mine from Amazon...
 
Why not reuse the bronze gear and get a new shaft?? Yours is a hardened, improved shaft, you can tell because the hex portion is tapered instead of a sharp edge. Was the shaft chaffing on the main cap? Could the oil pump be the cause of the problem?
 
There are a couple options, just trying to figure out the best one. Not trying to save a penny, just want the most reliability to be honest. Can't reuse the gear because the distributor shaft won't fit into it. No idea why. Maybe it was smashed in a vice, or manufactured out of spec??
 
That looks like a Milodon gear/shaft. I bought one to use in my 434 but sent it back because it had .012" run out across the face of the gear. The Mopar bronze gear/shaft I replaced it with had less than .002".
 
I have the same gear for a roller cam. It's an interference fit, you must press it in. Heating the gear up in the oven and cooling the shaft in the freezer helps. Just a thought
 
Can't do that for the distributor!
 
Oops, I misunderstand what you said. Reread where the distributor won't fit properly. Odd problem. Is it the slot in the shaft that is too small, or is it the opening in the gear that is too small? Or both?
 
The opening in the gear is too small to accept the the bottom of the distributor
 
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