3406c mechanical question

I can tell u from taking care of 8 trucks with C models all with 3zj's you dont wanna time it to 17 or 18° unless its had a 18° cam put in it...it should be between 10.4 and 11° depending on the serial#...thats between 12 and 13° dynamicn(running) timing...u need a cat 8T-5300 timing meter to check it properly. does it have a boost guage? If so how much does it make?

 

I agree on needing a meter to time it properly. Especially if your advancing it a little. Yeah they set at 11 from the factory. It's all in what you want outta one. I will say no more.

 

Now just out of curiousity if one wanted to change the timing (because its not set correctly), would it be as simple as rotating the pump a couple degrees?

 

The pump isn't slotted like most pumps you find on smaller motors. But once the pump is pinned and the advance is loose you can rotate the crank a little to either advance or retard the timing. A meter is needed to know for sure the base you want is achieved as well as start of advance and how much it advances with rpm. Pin timing off the slots doesn't guarantee factory spec accuracy but will be close. Also depending on who you talk to will depend on if a little advance or retarded timing is best.

 

Not a CAT guy here, but I always like talking injection timing, Cummins ISX went through the same ordeal, before introducing EGR they retarded timing to 17.5 static injection, but if the timing wedges weren't used properly can sometimes be quite out to lunch, then had issues with plugging oil filters from shellac, but they made cam timing wedges to advance up to 21 static injection, i usually set them at 19.5. and been successful, engines hauling 100 000 pounds and hitting high 6's

 

Peterbilt's "Super Truck" only gets 10.7 mpg.