Timing Trouble!!!!!

dsl kicks gas

dsl kicks gas

Runnin on Broke
Joined
Aug 13, 2007
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546
im having a he!! of a time getting my pump timed. i tried setting it with the timing pin, still the same result. it idles rough with a lot of white smoke. and it dont want to come off idle with out poping and cracking. i used a scred driver to confirm tdc, im running a cam gear off a 24v(no pin hole)

i switched out my pumps so it has to be an issue with the engine or finding TDC.
 
not sure, but when we did mine, we didn't change the cam gear, but still used the timing pin when we changed pumps. initially, i just lined up the crank and cam marks for tdc while i had the cover open, then i knew i was good to go. i slipped the timing, and we tried doing the screwdriver, but we found out we were going off an exhaust stroke.
 
i have tried setting it 5.4mm of lift 18.5* and with the timing pin(should be like 14*) with the same result.

ok do you set the timing off the start, or end of tdc? im going off the middle.........
 
middle

same place u chk it with a light

which would prolly be a good idea in your case
 
I wonder if you were on the exhaust stroke when you found TDC? A good way to check is to look at the valve movement of cylinder #6 if you have #1's valves removed. If you use the alternator nut to turn the motor, watch for the intake valve to come all the way up on #6 followed by the exhaust valve just starting to move down. At that point, you will be on the exhaust stroke of #6 and therefore at TDC compression stroke for #1. Since there is a tiny bit of valve overlap on these older motors, you should be really really close to TDC on #1 when the exhaust valve of #6 just starts to move.
 
I would do the drop valve method to confirm TDC. Using a screwdriver to find TDC doesn't seem all that accurate. There is a good amount of dwell at TDC.
 
Screwdriver? Why not use the valves, been doing it that way for years.

Jim
 
^^^^

Drop valve method will be the best way to find TDC on #1. VERY easy to do. Screw driver is as accurate as eye ballin' the thing.

Other question is, are you barring the motor over in the correct direction of rotation?

Is the cam installed correctly?
 
cam is installed right.

i have no idea why i didnt use the valve drop........i guess its just been a stressfull week. i'm going to run out and give it another shot ill let you all know how it goes


thanks josh
 
whats the drop valve method? im new when it comes to finding TDC and pump timing
 
Big Blue24 said:
I wonder if you were on the exhaust stroke when you found TDC? A good way to check is to look at the valve movement of cylinder #6 if you have #1's valves removed. If you use the alternator nut to turn the motor, watch for the intake valve to come all the way up on #6 followed by the exhaust valve just starting to move down. At that point, you will be on the exhaust stroke of #6 and therefore at TDC compression stroke for #1. Since there is a tiny bit of valve overlap on these older motors, you should be really really close to TDC on #1 when the exhaust valve of #6 just starts to move.
Click to expand...

would an aftermarket cam change your results?
 
make shure your pump gear lockwasher is good and toque it down to 145#

simple stuff but sometims the small things get over looked
 
94 12valve said:
I agree ... but changing the cam can change how much overlap you have.
Click to expand...

would it have more or less valve over lap? i could see either way.....less with a ground cam....or more...to clean the cyl out better/longer(scavaging)
 
dsl kicks gas said:
would it have more or less valve over lap? i could see either way.....less with a ground cam....or more...to clean the cyl out better/longer(scavaging)
Click to expand...

That all depends on the LSA of your ground cam. My point was with the valve method and an aftermarket cam you could still be off TDC.
 
There are two different "methods" using the valves. One is watching valve movement directly from the cam/pushrods/rockers. This is a good approximation of TDC and probably just fine for setting timing since DV's, Line Size, Injectors all effect timing so +/- 0.5* will not make a difference.

The other true "valve drop" method requires removing a valve spring on cyl #1 and marking the dampener when the valve stops moving up. Keep barring the motor and mark the dampener a second time when the valve starts to fall. Half-way between the two marks is true TDC. Essentially, the valve rides the piston and when the piston reaches the top of it's stroke, the valve stops rising. There is some "dwell time" at the top of the piston stroke so you continue to bar the motor till the valve starts to drop. Halfway between is true TDC.

If you are a perfectionist, it's difficult to judge precisely when the valve quits moving up, a precise method is to mark the dampener when a measured amount of the valve stem comes out. Example: Remove #1 intake valve spring and let valve drop down onto the piston. Bar the motor over till the valve stem is protruding 1". Mark the dampener. Continue to bar the motor until valve stem raises all the way then falls to 1". Mark the dampener. Measure between the marks and put a permanent paint mark halfway between. This is true TDC.


Caution: Do not remove the valve spring until the piston is close to TDC, otherwise it will fall all the way through.

Tip: Push down on the valve as you're barring the motor because the sticky valve guide will not let the valve drop properly.

Tip#2: If using the alternator nut to bar the motor, you can only turn the motor over backwards. If you go too far, you're stuck. Unless you use a 3/8" breaker bar and put downward pressure on the tensioner pulley, then it is possible to bar the motor forward.
 
Big Blue24 said:
There are two different "methods" using the valves. One is watching valve movement directly from the cam/pushrods/rockers. This is a good approximation of TDC and probably just fine for setting timing since DV's, Line Size, Injectors all effect timing so +/- 0.5* will not make a difference.

The other true "valve drop" method requires removing a valve spring on cyl #1 and marking the dampener when the valve stops moving up. Keep barring the motor and mark the dampener a second time when the valve starts to fall. Half-way between the two marks is true TDC. Essentially, the valve rides the piston and when the piston reaches the top of it's stroke, the valve stops rising. There is some "dwell time" at the top of the piston stroke so you continue to bar the motor till the valve starts to drop. Halfway between is true TDC.

If you are a perfectionist, it's difficult to judge precisely when the valve quits moving up, a precise method is to mark the dampener when a measured amount of the valve stem comes out. Example: Remove #1 intake valve spring and let valve drop down onto the piston. Bar the motor over till the valve stem is protruding 1". Mark the dampener. Continue to bar the motor until valve stem raises all the way then falls to 1". Mark the dampener. Measure between the marks and put a permanent paint mark halfway between. This is true TDC.


Caution: Do not remove the valve spring until the piston is close to TDC, otherwise it will fall all the way through.

Tip: Push down on the valve as you're barring the motor because the sticky valve guide will not let the valve drop properly.

Tip#2: If using the alternator nut to bar the motor, you can only turn the motor over backwards. If you go too far, you're stuck. Unless you use a 3/8" breaker bar and put downward pressure on the tensioner pulley, then it is possible to bar the motor forward.
Click to expand...

But for thoes with out a spring compressor, just remove #1 injector and use a screw driver. Same process and just accurate.
 
Hey thanks for the info guys this will come in handy when i do my p pump swap. Any special place to mark the dampner?
 
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