could someone explain to me how to find TDC by using the drop valve method, I think I missed something somewhere because I timed my pump & now It won't run & after trying to pull it off I have fuel coming out the exhaust manifold??? I'm not real sure but I think I might have screwed somethin' up somewhere in the process????? I'm thinkin I might have it just about the opposite of how it should be, I can't win for losing it seems, I just paid $345 to have my pump put on the stand & when I put it back I apparently didn't get the lash on the gears set back right( only thing I can figure???) & I drove the truck about 1/2 a mile before the pump gear slipped & I tried resetting everything today & getting the lash right & now it won't run at all??? I tried the drop valve method because I could not for the life of me get the dang pin for the motor to line up??? I decided since most seem to think the pin is not the best way for finding TDC anyway, I'd go another route well I still have a truck that won't run oh well, maybe tomorrow will be a better day???? thanks for any replies, Dusty

 

Here is how Josh Peters told me to do it, and it worked like a charm. Turn the intake valve in 3 turns so it stays open, very carefully turn the engine over till it touches, make a mark on the dampner, then back it up, turn the valve back in so it's closed, turn the engine over so the piston is past TDC. Then turn the valve back in 3 turns and back the engine up till it touches. Make a mark on the dampner. Measure Half way between those marks and that is TDC. Reset your valve lash and your good to go. No messing around with pins, and you know for sure where TDC is.

 

that's what I did, but I used the exhaust valve on the # 1 cylinder & I turned it down so it would stay down & rotated the engine counterclockwise until it touched & marked the damper, & then w/out adjusting the valve I turned the engine clockwise until it touched that way & then marked the damper, & then measured the distance between the two & then moved the engine until the damper lined up with the center mark, then installed the pump gear, & now I have no fire?? should I have used the intake valve instead of the exhaust valve???? oh & also i did readjust the valve afterwards, maybe the exhaust valve would explain why I am just dumping fuel out the exhaust & it's not being compressed & burned??? does this make sense?? Dusty

 

I'm not positive if it makes a difference which valve you use, but it seems that you would be one complete revolution off on your timing now. You would be injecting the fuel during the exhaust stroke, that's why it's spewing out. Because the pump runs at 1/2 the speed of the engine does. Someone correct me if I'm wrong, but I would still try it again with the intake valve. Good Luck

 

I'll do that in the morning, seemed to me that I was just about opposite of where I needed to be, so I think going back & doing it w/the intake valve should take care of the problem, might try pulling the timing pin for the engine & feeling for the hole on the cam gear, just to get me close, it ran great with it timed by the engine pin for the short period that it ran , thanks a bunch, Dusty

 

You're probably be off on your TDC a bit. You were at the top of the intake/exhaust stroke instead of the compression/power stroke on one of your markings. There's a good chance the cam was starting to open the valve pushing it into the cylinder. The piston would have been at different locations when you marked the damper. The drop-valve method must be done at the top of the compression stroke only. That's the reason for marking one side, backing off the valve, rotating past TDC and backing it up for the second mark.

To get yourself back on track, pull the #1 valve cover and find TDC like Crimedog said. Then set up your dial guage. Rotate the engine and watch the intake valve. You'll see it open and close. About a 1/2 revolution later you should see you dial guage start to respond. If it doesn't, you're out 180 degrees. Rotate the engine until you get the dial reading you want, pop the timing gear and rotate watching the intake valve. It will open and shut on the intake stroke. 1/2 turn later will be TDC on the power stroke.

A little trick to mark TDC is use a piece of masking tape for the marks and peel it back over itself to find the mid-point. It's a lot easier than trying to measure.

Good luck with it all.

 

Good points, I forgot about the overlap on the exhaust stroke that can mess up a good measure of TDC.