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> Timing, something out of whack
trojanhorsepower
post Dec 10 2003, 07:45 PM
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I have the fan on there so I can turn the motor. Also I put the fan housing on there once to see where the notches line up on the case, then took the housing off to make it easier to turn the motor. I have inspected the fan and can not find an "O" like I said, just the two timing lines.

Jake, turning it CCW made since, but when I do that the intake opens as the piston goes down
like it should but as the piston comes back up the exhaust valve opens???
Thesey914, I was afraid of piston/valve contact to, but I do not hear/feel any as I turn the motor.

Thanks for all the help

-Pete
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trojanhorsepower
post Dec 11 2003, 11:27 AM
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Well if nobody has any more suggestions I will tear down the motor and redo the cam timing. Can I reuse my head gaskits or should I get some new ones?

Thanks again every body

-Pete
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Brad Roberts
post Dec 11 2003, 12:36 PM
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Not all fans have the O mark on it. The flywheel should have an arrow pointing forward on it also for TDC (unless it is a lightened flywheel)

I'm not quite sure why you are so eager to crack the case.

So far I have read nothing hinting at the fact that the cam is in wrong.

Feel free to pull it apart.. Digital pics would help a lot.

Adjust the valves and fire it up on the ground before it goes into the car. The worst it is going to do is pop and backfire out the intake or exhaust.

Even if the valve adjustment is off big time.. it will run and you will hear it clearly ...then shut it down.

Something else you havent said anything about: put it on what you think is TDC no.1 ..then tell me where the dizzy drive is pointing (take pics with throw away camera and have them developed onto CD). It will save you a boat load of time over cracking the engine.

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2teeners
post Dec 11 2003, 12:58 PM
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QUOTE
turning it CCW made since, but when I do that the intake opens as the piston goes down
like it should but as the piston comes back up the exhaust valve opens???



turn it the other CCW. then it would work.

ie; exhaust valve opens as the piston goes up, then intake valve opens as the piston goes down. both valves are closed as the piston goes up (compression stroke) TDC Fire! piston goes to bottom, back to start.

I see no problem there. when the engine is turned where #1 should fire, make sure that if you put the dizzy in there it it will point to where #1 is supposed to be. if it doesn't, pull out the distributor timing gear under it and set it to where it will. Not uncommon at all for people to just change wire positions when the gear is not in right.
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trojanhorsepower
post Dec 11 2003, 01:31 PM
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OK I know that I am not being clear.
Brad no one wants to take this thing down less than me.
The dizzy is wrong, I am almost certain of that since I installed it based on what the rockers were doing and not what the crank was doing.

Here are some photos
With the mark on the crank pully and the fly wheel up
piston is at the top
exhaust valve is slight ly open
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trojanhorsepower
post Dec 11 2003, 01:34 PM
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Marks up
Piston up


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Brad Roberts
post Dec 11 2003, 01:34 PM
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Damn.. now I need to leave...DOH!


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trojanhorsepower
post Dec 11 2003, 01:36 PM
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Rotate 180 deg. CW piston is down intake is slightly open
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Brad Roberts
post Dec 11 2003, 01:36 PM
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Pushrods are not sitting in the lifters correctly. If it was built on a stand or bench.. then you stand a chance of not getting the pushrods seated in the lifter bore. This will make it appear WAY our of whack.

Easy fix. Loosen the adjuster and put a flat blade screw driver under the pushrod and see if you can lift up on the push rod.

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Brad Roberts
post Dec 11 2003, 01:38 PM
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I rotate the engines over on their side when I drop the pushrods into the lifters. This lets me know quickly whether or not they are seated properly. Doing it with the engine in its natural position (flat) is a crap shoot. I can do it both ways.. because I know what it feels like when they are out.

Oh.. and not all of them could be off. It may be one or two.


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trojanhorsepower
post Dec 11 2003, 01:39 PM
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damn try again


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trojanhorsepower
post Dec 11 2003, 01:44 PM
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These pics are not helping.

I am going back to the shop and I will go throught the whole cycle.
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Brad Roberts
post Dec 11 2003, 01:46 PM
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Check the push rods............



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trojanhorsepower
post Dec 11 2003, 02:16 PM
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I went and pulled the rocker arms and checked the push rods, they were seated properly (I put them in with the motor turned up).
Here is the cycle

Start:
Piston up crank marks up
exhaust valve is slightly open
Rotate CW as the piston goes down the exhaust valve closes
Piston at bottom and starts to come back up the intake opens closing when the piston
reaches the top
Continue to rotate CW and both valves stay closed as the piston goes up and down, as the piston reaches the top the exhaust valve begins to open, and we are back were we started.

Start
Piston at top rotate CCW

intake starts to open as piston goes down
closing when piston reaches bottom
as piston comes back up the exhaust valve opens closing when piston is at the top.
Continue to rotate and they both stay closed then it starts over.

-Pete
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Jake Raby
post Dec 11 2003, 02:19 PM
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Sounds like you are starting at "overlap" not at "TDC" BIG DIFFERENCE.....
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Brad Roberts
post Dec 11 2003, 02:19 PM
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CW facing the fan or CW facing the flywheel ?


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trojanhorsepower
post Dec 11 2003, 02:26 PM
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CW facing the fan
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Brad Roberts
post Dec 11 2003, 02:30 PM
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Correct. It sounds like you are not starting at number 1 but instead starting with number 3 at TDC (but your standing and showing us number 1 because you think you are on number 1 TDC)

Leave it like it is and adjust number 3.. then go to 2..


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trojanhorsepower
post Dec 11 2003, 02:39 PM
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Brad, Jake
Thanks for all the help guys.

I will go out and try again.
What way does the engine turn when it is running?
Facing the fan will the fan go CW or CCW?

-Pete
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Brad Roberts
post Dec 11 2003, 02:42 PM
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The fan turns CW while facing it. In the car.. I grab the fan from the passenger side and pull it towards me (CCW) to adjust the valves.. if I dont use the 5th gear method.


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