dizzy/ cam gear problem

[amcjunky]

ok so i am going to post some pictures of the couple sets of cam and dizzy gear that got chewed up in my motor. I know that oilling was not the issue because i had between 40psi at idle and 80psi at high rpm and i had the little hole drill above my dizzy for extra oiling


so my question is what else could have caused this. if i order the matched cam gears and new timing cover from bulltear will that fix it? i use a msd dist ( the amc style one).







these two were a set both amc brand gears










and these two were a set the dizzy gear was msd and the other one cam with the motor

the first set lasty say 5 or 6 pass down the track and the second last 10 -15 can exactly remeber

i hope you guys can give me some help in figuing this out

thanks justin

[tufcj]

Several things.

Do you have the positioning dowels in place for the timing cover? They are critical for the proper alignment of the gears.

The dizzy gears drive the oil pump, too much pressure puts too much strain on the gears. My AMX ate a set with pressure similar to yours. I went back to a standard pressure relief spring when I replaced the gears and haven't had a problem since. Also make sure the relief plunger is in right (point forward), and it moves smoothly in the bore.

Gears. They MUST be a matched set. There are at least 3 different known tooth pitches used by different manufacturers. Different mismatched pitches = extreme wear. I think the MSD gear is a variant of a Chevy gear.

Make sure the oil slot in the upper cam gear is open. A lot were blocked by casting flash. This feeds oil from the front cam bearing thru to the inside of the dizzy gear. There's more than enough oil flow if this passage is open.

Bob
tufcj

[amcjunky]

yes both dowel pins are there and i never built this motor i bought it as a whole. i will check the relief plunger tonight

thanks justin

[jeepsr4ever]

Turn pump by hand with a screwdriver. Pump should turn easily. Also check relation to distributor to T cover when it is all the way down and in and make sure you dont have a gap on the distributor.

[Mudrat]

Turn pump by hand with a screwdriver. Pump should turn easily. ... .

Caveat that - should turn easily if NOT filled with notoil!!

Once the engine is all together and the system filled with oil, it takes a heck of a drill motor to keep turning the pump.

[jeep_man_401]

I had same MSD dissy in a new rebuild and used the old cam gear. I ended up with the same results. Ordered a set of Bulltear gears and have not had a problem since! I did have the oil pressure spike and blow the oil filter gasket but I think the plunger got stuck with crap from the gears going bad. Anybody pull the pan and look at the mains & rods after chewing a set of gears??

Like the water pump!

While u have the MSD apart, pull the plate for the pick-up coil and put some epoxy on the screw on the back side. My coil/pick-up went bad and you have to pull the whole dissy apart because the screw comes in from the back side and u can't tighten it from the top. You'll see when you tear it apart. A real time saver later on....

[jeepsr4ever]

Turn pump by hand with a screwdriver. Pump should turn easily. ... .

Caveat that - should turn easily if NOT filled with notoil!!

Once the engine is all together and the system filled with oil, it takes a heck of a drill motor to keep turning the pump.

No, turning with a screwdriver will not prime the pump. Even after you prime it turning with a screwdriver should be easy. Priming eats 1/3hp drills for breakfast =D>

[amcjunky]

here at the last main and #8 connecting rod bearing




also i had a anti cam walk plate in there



would that have affected anything?

i am going to buy a new timing cover and gear set from bull tear when i get the money is there anything else i should be checking?

thanks for the help guys

[Mudrat]

No, turning with a screwdriver will not prime the pump. Even after you prime it turning with a screwdriver should be easy. Priming eats 1/3hp drills for breakfast =D>

REALLY?? Once installed it takes a gorilla with a screwdriver or at least a 1/2 HP drill to spin the pump to get pressure???
It’ll spin with a driver, but won’t bring the system to pressure. And I’m thinking I may need to find my BT Priming Tool when I get back since it will have been 3 months since running my engine.

[ironman_gq]

I took apart my original dizzy and took the gear off and spin that with the drill to prime my pump. works really well as long as I dont push down which can drive the pump rotors into the housing and cause its own problems.