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I'm installing a gear drive in place of the timing chain but, there's no key or anything on the camshaft. do I reuse the "manual fuel pump disc" that is bolted on the camshaft?
I bolted it on without using it but figure I should double check with you guys before bolting the engine back together. What keeps the cam gear from slipping on the cam?

There has to be some kind of key on the cam or the gear will slip. There should be a slot in the cam for a key. You may have to pull the key out of the old cam or get a new one.

The fuel pump cam should also work the same as it did with the sprocket. It should have a tang that fits into the gear to keep it from spinning. Make sure it doesn't rub on the inside of the cover. The other thing you will notice is the cover has to be modified to clear the gears. There is a flap that sticks out and directs oil to the cam chain that will be in the way when you go to put the cover on.

My engine machinist talked me out of installing the gear drive I bought for my engine due to vibration and harmonics. I don't know if he had any direct bad experience with them or not or if it was just rumors passed down. Just about every diesel engine ever built and most of the early gas engines had gear driven cams but then they don't run the rpm that a high performance gas engine does.

no slot for a key, just a thrust washer on the back and a bolt on the front for the camshaft gears.
The truck is a '90 f150 with a 302, so it doesn't need the fuel pump cam but, I wasn't sure if the FP cam also helped the gear from slipping but like you said, it only has 1 tab that keeps itself from slipping on the gear.
I guess I'll just assemble it and see what happens, seems sketchy to me.

I've read lots of rumors, but nothing about someone officially hurting and engine. This truck only see's 1500 miles a year. I'll just have to eliminate the knock sensor.

The cam should have a pin sticking out of the front. Pull the gear off and check to see if the pin fell out for some odd reason. It needs to have some locating device. If you remove the gear and see a 1/4 hole and no pin then you need to locate one or it came out with the old cam sprocket.

ayye, ok. i'll post a vid this weekend

damon1272 wrote:The cam should have a pin sticking out of the front. Pull the gear off and check to see if the pin fell out for some odd reason. It needs to have some locating device. If you remove the gear and see a 1/4 hole and no pin then you need to locate one or it came out with the old cam sprocket.

Yes, you are correct, it is supposed to be a pin, not a key. There is only the single bolt that holds the gear on the cam instead of 3 bolts like a Chevy. You probably have to transfer the pin from the old cam or sprocket. I think it is a blind hole in the cam that won't allow the pin to fall back into the engine. There does however need to be a washer or the fuel pump eccentric to keep it from coming out the front.

There used to be a kit out there with eccentric bushings that fit on a machined pin to correct cam timing wiih a standard gear. Seemed like a good idea to me at the time a long time ago. It snapped off the pin at the reduced diameter of that pin. No bueno. I should have remembered that it was a pin.

went well, looks like I had the gear already on the pin but I didn't have the timing cover seated properly. Everythings back together and runs good. knock sensor is still hooked up and I don't feel any retardation, but the sensor may be bad already.

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