Problem when timing my P pump please read?

KingS

KingS

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Nov 29, 2006
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Ok guys I have set the timing on quite a few 12v's but never set one to higher the 19.5 deg.

Here is my issue I was trying to time my personal 12v to 23 deg, I would get my mm of lift on the dial indicator where it is needed to be. Then I took the gear loose and the problem happens everytime I pop the gear off of the pump shaft the pump will spin back. I am assuming this is do to the cam lobe pressure inside the pump.

Has anyone over had this issue? If so, how do I get the pump to stay in place when the gear comes loose? The highest I can set my pump without it doing this is 20 deg. Thanks for any help.
 
Figure out how far you have to move it on the harmonic balancer. Back the pump off to a point where it will stay in place when you break off the taper. Rotate and lightly tighten the nut. Re-check your timing. Repeat if needed.
 
I have found that on a stock 215 pump at 23.5 it will jump the lobe on the pump cam. However I could time it to 22.5-23 and not have an issue, as long as the gear came off easily.
 
Pin the pump, remove the gear, rotate the engine back however many degrees you want it set to, clean the shaft, and then tighten the bolt to about 25 ft lbs, then remove the pump pin, and torque to 160 ft lbs, then recheck timing to see if it's set where you want it.

If the pump is set for 14*, and you want 23*, you'll need to rotate the motor backwards 9*. If the harmonic dampener is 8" across, pi times 8" = circumference or 25.13". There are 360 degrees in a circle so 9* is 9/360 times 25.13" = 0.638".
 
Pop the gear loose before you set the lift. Then reset the pump on with as little torque on the nut to keep the gear from slipping as you bar the engine as you bring the pump up to the desired lift. Sometimes it takes a couple stabs at it. I ended up collecting some nuts and a bolt, and had a friend weld it together so I can just set the engine at TDC, and turn the pump with a wrench to desired lift. No messing about.
 
Sounds normal to me, Pin the pump method.......I don't even own a dial indicator, I put faith in the pump timing and do math using the balancer.

Jim
 
Good advice above. Sometimes they jump and sometimes they don't in my experience. Just reset and spin back to desired lift as indicated above by a few.
 
Thanks again guys, now I can have the 23 deg. that I need to finish my setup the truck is pushing close to 700 at 19 deg. now I figure the 23 deg. will put me into the high maybe close to mid 11's and an even greater street daily driven then it already is now.
 
Jim Fulmer said:
Sounds normal to me, Pin the pump method.......I don't even own a dial indicator, I put faith in the pump timing and do math using the balancer.

Jim
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How? I have a pump sitting that I need to set. I would like to learn your method.
 
Trapper said:
Would ya happen to know what a 215 pump is pinned at?
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Well that method works best if you know what your pin is at. If i remember what Seth told me correctly a 215 pump is between 12 and 16 to be in spec, but that does not mean it is in spec, and even with that, you could be off 4* using that method. If you assume 14* it should keep you within 2* of what you want.

FYI my pump was on the low side at 12* pin.
 
Timing on these truck does not seem to be an exact science. If the pump is stock, it should be somewhere between 12* for an older 160 pump, and 14* for a 180 or 215 pump. If the pump has been to a pump shop that reset the timing to a different value, the only way to check it is with a dial indicator or removing the #1 line and holder and spill port timing it.
 
When you time it just remember the crank makes 2 revolutions for every 1 revolution the pump makes, that being said you have to double the degrees you turn the damper. Ex: You are shooting for 20*, the pump is pinned at 14*, so that is 6* you have to time the motor but since the crank runs 2x more you have to run your damper back 12*. Just something to keep in mind
 
You'd turn it back 6 degrees, its crank degrees for timing, not cam or pump.

Also take the lock timing with a grain of salt. My 12mm pump was supposed to be locked at 17 degrees, it came back with 12. They went by the timing chart of a stock 160 pump, didn't take in account a different camshaft in it.
 
Trapper said:
How? I have a pump sitting that I need to set. I would like to learn your method.
Click to expand...

Dia X Pie (3.1416) divided by 360 X degrees desired!

Example: 9.25 X 3.1416 divided by 360 X 5 = .4036......find true TDC using the drop valve method, pin the pump, pop the gear and roll the motor backwards 4/10ths of an inch and finish everything else up.

I don't get too technical about timing, meaning I don't nerd it out, I've never see much of a difference in a degree or two, keep in mind that no matter which method you use, they are only as accurate as your TDC mark.

Jim
 
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