broke a cam gear in a farmall m

hello, i put a live pump on my 51 farmall m, it worked fine till i was going down the road and suddenly the motor spun down with no power as if i had pushed in the kill switch so i did run threw of my check list the motor would turn over it had fuel and power to the coil so i pulled the cap of the distributor and the rotor was not turning so i pulled the pump/distributor off and the gear for the cam shaft had split. so we drug her back to the shop and pulled the gear out now it is a three hole cam gear. my question is can i get a heavier gear out of a later model of tractor and if so what is the best one to use with this live pump? second off how do i time the cam with the new gear? and at this time i may compleatly rebuild the motor.

Nick

Get a late model SM, SMTA, 400. 450 gear, they are much harder. I had it happen to me also a while back.

Yes line the crank and cam gear marks up. If one gear has 2 marks put the one mark gear mark in the center of the two.
If getting a used IH gear look for one with the number on it ending in DB. DA also works but is machined to be a little less of a press fit on the cam.
Aftermarket sells new gears now, probably this YT site still sells them.

(quoted from post at 19:06:54 09/08/14) Yes line the crank and cam gear marks up. If one gear has 2 marks put the one mark gear mark in the center of the two.
If getting a used IH gear look for one with the number on it ending in DB. DA also works but is machined to be a little less of a press fit on the cam.
Aftermarket sells new gears now, probably this YT site still sells them.

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so if i replace the gear on the cam with a new gear the mark on that new gear will be good to use if i reuse my old crank gear and old distributer gaer?

I would think new gear would be marked properly in relation to the key slot. Compare with the original.
Also, its possible you have valve train issues too if the cam and crank got out of time. Pull the valve cover and check for bent push rods or any other damage in that area.
good luck
Dennis

I had one old-timer tell me many years ago not to use the cast iron cam gear when you put a live pump on an M or W-6 because it will break the gear. He claimed that IH sold a steel replacement cam gear specifically for use with a live hydraulic pump. Unfortunately that is all that I got from him--maybe someone else on here has heard of that before?

use a 400 or 450 cam gear they were built to pull a hydraulic pump. you can tell by looking at them, there about twice as thick in the center webbing. Steve

Nick

Sorry I didn't get back to you quicker, but I only check out the sight once in the am. You got a good response anyway.

Replacement gears should be marked the same as the original ones. Line the one mark on the crank and cam gear up. Then in case a magneto is ever used on the engine, put the ignition drive gear mark between the two marks on the cam gear. If using a distributor the ignition drive gear line up is not critical.
On 400 engines serial number 155941 farmall and 155980 international IH started putting cam gear # 6760DB in the engines. They used that gear in all the 6 series engines after that and sold it as the replacement for 6 series engines after that except for ones already in the parts system when they were a company. If you look at a later parts list for a M on up that's the gear number shown.
Aftermarket gears sold now should be patterned after the 6760 DB gear.
Only difference in the 400 6760DA gear and the DB was the ID of the center hole was made smaller for a tighter fit on the camshaft with a DB.
IH recommended the camshaft be removed from the engine and supported behind the front cam bearing journal when pressing the 6760DB gear on the shaft.
Whatever way you decide to do things, if the gear fits tight on the cam. Don't go pounding on the gear if installing with cam in the engine. Block plug in rear can be knocked loose or oil pump parts can be damaged with rough treatment.