pump timing

G

gwhammy

Active member
I've got a motor on the floor that's getting resealed and the typical gsk and some pump timing. I have a degree wheel and was thinking this would be the most accurate way to advance the timing. Am I right if I back the crank up 5 to 6 degrees that will put me at 17 to 18 degree pump timing? It's a 175 horse 95 motor.
 
^^THIS

I read a good thread about this. Seth seems to be the agreed upon expert on pumps around here and he says this is the ONLY accurate way to do it.

Know the factory pin timing, pin it, degree it backwards.

If you ever send it to him to be looked over I believe he can also put the pin at any timing you want.
 
I like doing it with the degree wheel after finding exact tdc. Working with the pin is fine but often I’ll pull the DV and find port closure to be sure that the pin is where it’s said to be and not bent. It can be done using the balancer as well. Using circumference of the balancer divided by 360* to achieve inches per degree and marking the balancer accordingly.
 
Maybe I'm a little crude. The timing cover is off to see where the dowl pin is. I also pulled the pump to reseal the lifter cover. Basically I popped the pump gear loose with the timing cover off without turning the motor or pump over. When I put the pump back on I zeroed the degree wheel on the crank and backed the motor up 5.5 degrees then tightened the pump gear back up again without turning the pump. Didn't pin anything just made sure not to turn anything over. I've done it this way in the trucks also just measuring the harmonic balancer but this has to be alot more accurate. This was an untouched stock motor also.
 
gwhammy said:
Maybe I'm a little crude. The timing cover is off to see where the dowl pin is. I also pulled the pump to reseal the lifter cover. Basically I popped the pump gear loose with the timing cover off without turning the motor or pump over. When I put the pump back on I zeroed the degree wheel on the crank and backed the motor up 5.5 degrees then tightened the pump gear back up again without turning the pump. Didn't pin anything just made sure not to turn anything over. I've done it this way in the trucks also just measuring the harmonic balancer but this has to be alot more accurate. This was an untouched stock motor also.
Click to expand...

I just don't trust myself to KNOW that i didn't move the pump at all between taking it out, setting it down,picking it up and reinstalling it. I have read that you can turn the pump when putting the nut back on as well. not saying a degree +/- would be catastrophic on a stock/lightly modified motor.

But on a high HP app or if someone walked by (I have kids) and turned the pump it could be 10-20* off and that is bad news.

Your mileadge may very but it takes very little time to pin in and know for sure where you start.....then degree wheel FTW.
 
I've done several pumps the redneck way. This is actually the first I have had out on the floor. 99.9 percent the pump didn't turn when out. I'm the only one in the shop and was real careful with it. Time will tell I guess. It's amazing how little you turn the crank to get 5.5 degrees. With the pump turning half of that I would think there is alot of room for mistakes doing it the pump way.
 
I've always set them by the balancer, I also like to back the crank up more than needed then go back clockwise to the degree your changing to get rid of any play or backlash in the gears.
 
I thought about that but this is just a mild motor going into a 06 super duty. If it was a true 12.5 from the factory I added 5.5 degrees so it should be 18 but anywhere from 16 to 19 is fine with me.
 
gwhammy said:
Maybe I'm a little crude. The timing cover is off to see where the dowl pin is. I also pulled the pump to reseal the lifter cover. Basically I popped the pump gear loose with the timing cover off without turning the motor or pump over. When I put the pump back on I zeroed the degree wheel on the crank and backed the motor up 5.5 degrees then tightened the pump gear back up again without turning the pump. Didn't pin anything just made sure not to turn anything over. I've done it this way in the trucks also just measuring the harmonic balancer but this has to be alot more accurate. This was an untouched stock motor also.
Click to expand...

I've done timing on some pumps that would love to jump backwards at the slightest bump. I'd bring them to the desired lift, and when I'd go to pull the gear, it would shoot backwards. That was with the gear barely set for turning only. The point being, when you popped the gear off initially, you may have lost your initial position and are setting it blind.
 
I machined tick marks in my stock balancer. Might be a little excessive, but with the right equipment it's easy. After reading that thread with Seth's advice I figured it was the best way to go.
 
Tate said:
I've done timing on some pumps that would love to jump backwards at the slightest bump. I'd bring them to the desired lift, and when I'd go to pull the gear, it would shoot backwards. That was with the gear barely set for turning only. The point being, when you popped the gear off initially, you may have lost your initial position and are setting it blind.
Click to expand...

This is my point....It is so easy to set it up the "right" way...why risk it.
 
I've never had one move or jump if the timing pins in the window. I don't put the pin in because I'm afraid I'd forget it and turn the engine over sooner of later. But with the pin in the window the pumps not under any tension and will stay there.
 
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