[68 TT]

Originally Posted by Daner

Hello everyone I've been lurking around reading build threads and finding answers to a couple questions and now I have what seems to be a new one.

Truck is a 67 fleetside with a 250 and 4 speed tranny

This spring I brought the engine with me to college and had a machine shop bore the cylinders deck the head turn the crank and do all the valve work and new cam bearings.

I put it all together in my free time and by early June she was running.

My problem now is when I'm driving it. I get what sounds like gear noise in normal driving around 45mph + when the engine works harder. It also happens earlier if I work the gas too hard. My kit came with what it said was matched crank and cam gears. The cam gear is aluminum. When the truck is stopped and I move the throttle on the engine I can't replicate the sound. Seems like it needs to be under load.

Instructions with my comp cam said 30min break in. I got the same gear sound about 20 mins in. continued the break in for 5 min just under the rpm where the noise started and called it good.

I used lucas oil break in additive and also added a jug to the oil when i changed it after break in. I checked the filter and didn't see anything alarming. Engine has about 170 miles on it since break in.

My cam grind isn't radical I think its 255. I'd have to check for sure. I also added a HEI distributer from Langdons.

Also the sound only seems to happen when the engine is warmed up.

All questions and replies are welcome. Thanks

Something has been damaged during the cam break in and is causing your noise.

I have seen distributor gears tear up cams before. Pull your new HEI and take a look at the teeth.

Have you changed the break in oil yet? If not then do so and check the oil for metal shavings. Also cut the oil filter apart and see what it has caught. The different metal colors will help tell you where the shavings came from.