Degreeing Cam Problems

1980_Cj7

Trying to check the cam this time and make sure it is right. I'm not getting anywhere close to the numbers the cam is supposed to have though. I'm doing it with the heads on and checking at the valve retainer. I know you aren't supposed to degree with hydraulic lifters, but could they make that much difference. I'm getting the intake valve opening .050 at 38 degrees ATC, and it supposed to open 4 degrees BTC. I'm getting an intake C/L of 99 degrees when it's supposed to be 105. What am I doing wrong? Checked and set the wheel at TDC many times, so I don't think that is the problem. I'd like to check on the edge of the lifter, but can't get the dial indicator in there and keep it parallel to the travel with the heads on.

Blown7

Even if you have the heads on check on the LIFTER BODY!! Use a washer on the lifter if you have to. If you can't measure down there with what you have, your going to get some better equipment. Jeff

1980_Cj7

I'll give that a try tomorrow. BTW, picked up a new cap for the Unilite with HEI style terminals when I was going by Summit while in Atlanta earlier this week. Wow, what a store! Now we won't have to change the ends on our plug wires.

1980_Cj7

Put a solid washer (slug) between the push rod and lifter, and tried to take readings off the top end of the push rod without the rocker on, but when the lifter comes all the way to the top, the slug would fall out of the lifter bore. Even at that, the readings were getting better though, so I guess the hydraulic lifter is the problem. Reckon I'll have to try to find a solid lifter somewhere.

AMX69PHATTY

The (2) Solid Lifters I used were MOPAR #1-P2843177

The Pushrod cup is deeper in them than a Hydraulic and
the Hydraulic is preloaded .020 to .050 at installation,
it's inner plunger is held in the body by an internal snap ring and
when adjusting rockers the preload keeps plunger off the snap ring.

One must figure in the lifters height differences, between a Solid Lifter and a Hydraulic lifter,
when using a solid lifter to check rocker geometry and determine correct pushrod length.

But for checking Cam Timing the height difference doesn't matter.

82Waggy

I you use a dial indicator on the lifter you should not need a solid. Might be easier to just get an extension for your indicator and drop it through the pushrod hole in the head. Are you using a piston stop to find TDC? Rotate both directions against the stop, split the difference for TDC and mark on the degree wheel. Pull the stop out. Rotate until intake opens .050 and mark degrees on wheel. Rotate again until .050 from closing and mark degrees on wheel. Split the diference for intake centerline. Rotate again until max lobe lift is found and verify against previous. Pull the timing set off and reclock it until correct. Repeat as necessary, OR, throw all that crap in the trash and line up the dots on everything! #-o Verify TDC mark on balancer!!!!