post h/g install woes - woe is me pinging

[semlin]

I would just try the 1st one, if it doesn't start (in a short time), remove the dizzy, crank it to the 2nd one and install dizzy again.

you can't tell which one is which. it is the same tdc timing mark on the pulley but, if i understand the FSM right, the cams have a 720 degree cycle that must be synched to the distributor. at first rotation to TDC the single dots on the cam face inward and on second rotation the double dots face in. only one of those is the right time to insert the distributor. Unfortunately it seems the only way you can figure out which is which is to pull the valve cover or, as doug mentions, trial and error with a 50/50 chance each time of being right when you insert the distributor at tdc.

what i don't understand is how it could make a difference. It seems to me that the distributor has only one 360 degree cycle so why would it care where the cams were? anyway, i'll figure it out some day.

the moral of the story is if the FSM is correct, do not ever crank the motor with your distributor gear out and make sure you note where the rotor pointed.

 

[IdahoDoug]

Excellent! The engine crank goes around once - cams at the top of the chain go twice, pistons driven by the bottom of the chain go once. But the distributor goes around only halfway. The distributor is the part that is odd - crank goes around twice and the dizzy once.

DougM

 

[KliersLC]

Glad you got er figured out, I realize that I am not the most eloquent poster around.......speaking of eloquent, Doug what are you doing up at this time of night???

Anyhow, I'll be doing mine before it turns warm here in potatoland, and I appreciate all the tips from others.
Congrats again!

Dan

 

[IdahoDoug]

Dan,

Just got done watching my last cycle of the news, put a few toys away, gave wonderful wife a backrub, and then checking on Sem's progress.

Now going to chat to argue about the Iran/nuclear issue while I wait to get sleepy....

DougM

 

[semlin]

I agree with Doug. A 2F will run with the distributer 1 or 2 teeth off but not more. I'll bet you are just 1 off or the mighty (but finicky) 1FZ would not run at all. Just experiment. Set it to TDC, go backwards 1 tooth and reinstall. I say backwards, because if you are pinging, it suggests you are way advanced, so you need to retard the timing. Keep us up to date.

turns out the mighty 1fz will not run if you are off one tooth to the right (retarded), but will run fairly well one tooth to the left but ping like crazy

 

[tech_dog]

This was a lot of fun to watch.

I just hope I have a major problem so that I can take better advantage of this board!

 

[landtank]

Well technically Semlin you need to be TDC of the compression stroke. Rotating the crank 1 turn from there you are at TDC of the exhaust stroke.

This is a 4 stroke engine so:

1st stroke is intake (piston going down w/intake valve open)
2nd stroke is compression (piston going up w/both valves closed)
*Spark happens at TDC*
3rd stroke is combustion (piston going down w/both valves closed)
4th stroke is exhaust (piston is going up w/exhaust valve open)

Glad you got it done.

 

[ElJefe]

Excellent! The engine crank goes around once - cams at the top of the chain go twice, pistons driven by the bottom of the chain go once. But the distributor goes around only halfway. The distributor is the part that is odd - crank goes around twice and the dizzy once.

DougM

Cams are not twice the crank... cams are actually sync'd with the dizzy at half the crank. 1 turn crank, 1/2 turn cams, 1/2 turn dizzy.

And anyone looking to find TDC without pulling the valve cover, pull #1 plug, cut the end of a 10-inch piece of heater hose SQUARE and spray with wd-40. Stick it down the plug hole to seal against the head around the spark plug hole. With a thumb over the end you will feel pressure as the piston comes up to TDC. if you are off by 360*, the pressure will be going out the exhaust valve rather than the spark plug hole.

 

[IdahoDoug]

Chris,

Right you are on the cams - obviously. Forgot there's a separate lobe for exh and int and one rev of the cams completes an entire cycle - whoopsie! Thanks for the correction. Good call on the heater hose method to find which cycle you're on.

Regards,

DougM

 

[semlin]

ok, great info, so to summarize, when installing a distributor you must

1. confirm you are at TDC on the pulley mark and also that you are on the exhaust stroke. Follow El Jefe's method for the latter if you don't have the valve cover off. Better yet, never rotate the engine pulley after you have pulled the dizzy.

2. line up the two match marks on the dizzy gear and body together and insert the dizzy more or less level with the harness plug at 12 o'clock. the rotor will move as you insert it following the helical gear and should end up pointed more or less to 12 o'clock or a few minutes before. the dizzy match marks are intended to find the right tooth if you insert the dizzy straight up using the harness plug on top of the dizzy housing to align. You don't need to mark the #1 cylinder as noted above.

3. if you get bad pinging under load, you are a tooth too far to the left or advance, and you need to go clockwise/right one tooth. If you don't run at all you are too far right and retarded one tooth. Either way, pull the dizzy half way out with your hand on the rotor. as soon as rotor feels loose the teeth are not meshed and you can turn the rotor in the direction.

there, i have distilled and parroted what everyone has taught me

 

[landtank]

1. confirm you are at TDC on the pulley mark and also that you are on the exhaust stroke.

No, it's TDC of the Compression stroke.

During a rebuild the engine should already be setup at this possition, However if you have disturbed it as Semlin did it won't be.

What I've found to be the easiest way to find it again is to pull all the spark plugs out EXCEPT #1.

Now when you turn the crank it will be easy to do until you get to start the compression stroke as that process gives resistance.

So you turn the crank clockwise as you face the front of the engine and as you feel that resistance continue turning until you line up the marks.

While doing this you might also hear air seeping out of the cylinder which is a good sign that you are where you need to be.

 

[semlin]

During a rebuild the engine should already be setup at this possition, However if you have disturbed it as Semlin did it won't be.

well, the cams were set up properly when I originally installed the distributor but once I started the motor you lose that baseline.

 

[Rookie2]

What I've found to be the easiest way to find it again is to pull all the spark plugs out EXCEPT #1.

Could probably just remove the #3 and #5. Aren't the other 3 on the exhaust stroke?

Edit: Maybe not. I guess you wouldn't feel the distinction as much with the other plugs in.

 

[Riley]

Glad to hear you're back on the road Simon. So ignoring the no garage issue, what's the banana rating?

Is this something I should think about attempting myself as PM or should I wait till she goes and find a pro to do it?