Babbitt

[Richard G.]

Is that a JD H main bearing?

 

[Mike(NEOhio)]

It's the right side main. The H has the clutch/pulley on the camshaft. All the others it's on the crankshaft. I made a puller to extract the steel sleeve but used the bolt to push against the bottom of the cup and you can see the result. I found another housing at a show and this time used a cross plate and pipe to press against the thick edge of the housing. One of the sleeves has the babbitt cleaned out, the other is as it was pulled.

 

[Richard G.]

I have a new right hand main bearing for my 41 H.
Are they machined to standard for the bearing?
A friend is letting me have it and I have not seen it yet.
Thanks.

 

[Mike(NEOhio)]

When they were current the replacement mains were on an exchange basis. I guess they thought the cranks would never wear. Mine was bad on the left side getting progressively less left to right including the rods and the crank had some scoring. I had it ground at a local shop. Told the guy only grind enough to clean them up and not worry about the size, I would machine to fit. The worst only needed .005 to .010 but he took them down over
020 and matched the mains and rods. And he didn't duplicate the radius in the corners. This place builds high end competition engines. I was a little disappointed but it will work.

 

[Richard G.]

Thanks Mike.
I am hoping to just be able to slide the new bearing on.
I replaced the crank about 20 years ago with a rebuilt one.
It was built back up to standard.
The old one had a bit of wobble to it probably because someone let the flywheel hit a tree at some point.
Put new rebuilt rods in with the rebuilt crank.
Thanks again.

 

[Mike(NEOhio)]

You should be able to just take the nuts off and work it away from the case. The oil is supplied from a hole in the case and the line from the pump and the fitting is on the inside so there's no disconnecting of the oil line. The oil flows around the bottom stud and up through a passage drilled through the rib. Make sure that is clear on your new bearing.

 

[Richard G.]

Thank you so much Mike.