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Timing, fuel delivery vacuum leak??

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75Cj5 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/08/2021 at 8:31am
Does everyone feel that I am ok with 21 pins between the cam and crank gear dots when the cam is clocked at the 3 o'clock position?

Edited by 75Cj5 - Apr/12/2021 at 1:32pm
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iapexl8r View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote iapexl8r Quote  Post ReplyReply Direct Link To This Post Posted: Apr/08/2021 at 8:03pm
The timing mark on the lower sprocket should be at 12:00 o’clock and the upper gear should be at 6 o’clock. So they line up . Your timing set should have instructions usually the o mark is zero and the little triangle  is advance and the square is retarded. You probably want the o mark .

Edited by iapexl8r - Apr/08/2021 at 8:08pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/09/2021 at 7:21am
Originally posted by iapexl8r iapexl8r wrote:

The timing mark on the lower sprocket should be at 12:00 o’clock and the upper gear should be at 6 o’clock. So they line up . Your timing set should have instructions usually the o mark is zero and the little triangle  is advance and the square is retarded. You probably want the o mark .
Like this  https://static.summitracing.com/global/s/instructions/edl-7800series-perer-tim.pdf - https://static.summitracing.com/global/images/instructions/edl-7800series-performer-linktim.pdf

Yes Sir, I did that for installation. My manual says to check by rotating the crank until the cam gear dot is in the 3 o'clock position, then to count the pins from dot to dot. Manual specifically calls out 20 pins but also says 20 or 21 pins is acceptable. I'm just moving forward with the 21 pin count.

Thank you!


Edited by 75Cj5 - Apr/12/2021 at 1:32pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/09/2021 at 7:34am
For any of you that are following this, I have buttoned up the timing cover and re-installed the distributor.
I re-installed the plug wires and double checked the wires are all going to proper positions on motor and distributor cap.
I have the mixture screws on the carb 1-1/2 turns out from soft seated position.

I have changed the amount of initial timing from 5* to 10* BTDC (ATDC on the timing cover)... this is really the only change I have made thus far.

I am going to get the coolant back in this afternoon and give her another try... 

Any other suggestions before this evening are always welcome.


Thanks for all that have participated in this thread thus far, I really appreciate it.


Edited by 75Cj5 - Apr/12/2021 at 1:32pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/09/2021 at 5:53pm
I just started it and it runs like crap still... turned the mixture screws all the way in and it will still start.

I replaced the power valve and still have the exact same result. 

Spits and pops in carb and now back firing through exhaust... 


The exhaust backfire is the only thing new.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote iapexl8r Quote  Post ReplyReply Direct Link To This Post Posted: Apr/09/2021 at 9:15pm
When your previously verified TDC did you verify it by running #1 piston up to TDC on the compression stroke verified by a piece of wire ran through the spark plug hole touching the top of the piston while turning the crank and watching the wire rise to TDC then fall as it passesTDC And back to the center of the rise and fall, then once the piston is verified  at TDC Look at the harmonic balancer mark, it should line up with the timing chain cover Mark. To find the compression stroke you can turn the engine with #1 spark plug removed and someone’s finger in the spark plug hole and when the compression pushes the finger off the hole that’s the compression stroke. Then after the balancer marks are verified, while at TDC verify the rotor is pointing to the electrode on the dist cap that is going to the #1 spark plug

Another thing to do is slap another carb on temporary to eliminate the carb being the issue, a carb is an easy one a lot of car guys have a spare carb maybe you can borrow one.

Also


If you have one of those infra laser temp guns you can check each exhaust manifold exit from the cyl for temp to verify no cold cylinders. In a pinch a bic pen with the cap on while the engine is running will slide from the heat and will not slide on cool cyl. 

The spits and pops in carb really sounds like timing.   we have all been there it can be frustrating, I hope my advice helps I try to over explain things I am not trying to be anything but helpful. The people on this forum have helped me many times.. yea you PHAT69AMX! Lol

-chris
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/10/2021 at 6:43am
Originally posted by iapexl8r iapexl8r wrote:

When your previously verified TDC did you verify it by running #1 piston up to TDC on the compression stroke verified by a piece of wire ran through the spark plug hole touching the top of the piston while turning the crank and watching the wire rise to TDC then fall as it passesTDC And back to the center of the rise and fall, then once the piston is verified  at TDC Look at the harmonic balancer mark, it should line up with the timing chain cover Mark. To find the compression stroke you can turn the engine with #1 spark plug removed and someone’s finger in the spark plug hole and when the compression pushes the finger off the hole that’s the compression stroke. Then after the balancer marks are verified, while at TDC verify the rotor is pointing to the electrode on the dist cap that is going to the #1 spark plug

Another thing to do is slap another carb on temporary to eliminate the carb being the issue, a carb is an easy one a lot of car guys have a spare carb maybe you can borrow one.

Also


If you have one of those infra laser temp guns you can check each exhaust manifold exit from the cyl for temp to verify no cold cylinders. In a pinch a bic pen with the cap on while the engine is running will slide from the heat and will not slide on cool cyl. 

The spits and pops in carb really sounds like timing.   we have all been there it can be frustrating, I hope my advice helps I try to over explain things I am not trying to be anything but helpful. The people on this forum have helped me many times.. yea you PHAT69AMX! Lol

-chris

I am beyond grateful for your advice, and yes this is sooo frustrating...  I did follow your procedure on finding TDC (I have also used a piston stop to ensure the timing mark on the balancer is in the correct position). I have second guessed myself everytime now but when I verify I did this the correct way I find that it is correct.

I am going to walk away for a couple days and look for another carb to try out I hate to think a brand new carb is already junk but it would not surprise me. 

I will be watching this thread and let you guys know if things change. Thanks again!!


Edited by 75Cj5 - Apr/12/2021 at 1:31pm
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Post Options Post Options   Thanks (2) Thanks(2)   Quote 6PakBee Quote  Post ReplyReply Direct Link To This Post Posted: Apr/10/2021 at 9:03am
Please stop with the green.  It makes it hard to read with these old eyeballs!!
Roger Gazur
1969 'B' Scheme SC/Rambler
1970 RWB 4-spd Machine
1970 Sonic Silver auto AMX

All project cars.

"Shotgunning works great for pheasants, not so great for electrical problems"

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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/10/2021 at 1:36pm
Originally posted by 6PakBee 6PakBee wrote:

Please stop with the green.  It makes it hard to read with these old eyeballs!!

Will do.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 75Cj5 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/13/2021 at 2:31pm
Well, it is looking like the cam has one or some lobes wiped...

I'm taking it down this weekend to confirm.



Edited by 75Cj5 - Apr/13/2021 at 2:41pm
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