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75 CJ5 not firing

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75 CJ5 not firing
I will check it again. Going out to work on it now. Will be back soon. To let you know. Ant I really appreciate all the help. Thanks
 
Travis4x4 said:
Is the firing order 153642
Click to expand...

Was just going to mention the possibility of incorrect firing order due to backfiring from carb comment...

Any luck after correcting?
 
To simplify our trouble-shooting there are only 3 things that could cause the engine not to start (assuming the engine cranks)
1. Fuel
2. Spark
3. Timing is so far off it won't start the engine.

We need to narrow it down to one of the above items.
 
ok I put the new plugs in and didn't gap them just left them like they where. would that cause a problem and what should the gap be. I did fix the plug wires to the correct order and then it wouldn't even spit back through the carb. I pulled the number one piston top dead center and the timing mark was lined up with 0 mark I turned the distributor 180 again and it back fired one time and nothing since just turning over. and to let you know when I bought the plugs I had to get the for a 78 my year called for 13/16 and my head has 5/8. And when I got the points and all the part store told me 75 up didn't have points and had to get them for a 74.
 
Sorry for the head ache guys. Thanks for all yalls help so far and not giving up. Cause I don't understand knew I should have stayed awake during auto mechanics class. :bang::bang:
 
I think You've just got something a little off...

Either the points are not set up correctly, or The firing order is still wrong / off on the cap / rotor.


Since it ran before you started all this, You need to try to stick with what you've messed with thus far to re-check everything and find what is wrong...

Do you know how to set the points right?

Did you make sure number one was TDC during the correct stroke when messing with the timing?
You mentioned having to turn the distributor 180... Not sure why? Your timing should never be 180 out and run. If it was before, it wouldn't have ran. If you turned it now, Not sure why you would need to. Hopefully you meant just the cap, because once you turn the distributor, that far, it can be B___ to get back right.

I would pull the number one spark plug. Bump the motor until the compression stroke of the #1 cylinder (the compression stroke is findable by putting your thumb over the spark plug hole you will feel the pressure of the cylinder trying to compress the would be fuel and air mixture before igniting it...), once on the compression stroke, with a small screw driver continue bumping until you get to the top of that stroke (screw driver in the spark plug hole and feel the cylinder move up all the way) It may take a time or two for you to get it right. Then make sure the cap and rotor are pointing to the correct plug wire (if not change it), and you have the firing order correct from that point forward (clockwise i believe, but i have a different motor...) Also at that point, the points should be OPEN (a gap between them) Check that gap too... Should be .016 ish, though i am not sure with that motor the specified gap, usually anything will run at .016 gap... If you don't have a "feeler gauge use a business card folded over. (cheap way, but not really correct, and can cause some poor running qualities, but at this point we want to just get you fired up..:D)

Put plug back in, hook up wires, and cap etc.

Then, if you need to, turn the distributor slightly one way or the other from there to get it to start.

This should work. If not you are either not getting spark from your coil, the battery doesn't have enough volts to crank good, or you have a fuel problem possibly, I know you said you're getting fuel, just repeating the ideas... :cool:

Good luck my friend,

~ JR
 
Well I can't get it to start and I'm frustrated with it. Anyone want it??
 
Ok I got it to back fire and spit back through the carb again now. But still not starting.
 
Old Dog said:
sure sounds like timing
Click to expand...
Exactly.
We have spark.
We have fuel.
Backfires into the carb.
I agree with Old Dog
Sounds like timing.

Position the engine so the timing mark indicates you are at TDC.
0900823d801d6950.gif
​
Then remove the distributor cap and make sure the rotor is pointing to where the #1 wire would be.
distributor_rotor_body_marked_no1plug_contact_point.jpg

​
Now the timing should be in the ball park. Next get out the timing light.We should be close so don't move the distributor much.
 
Do as Dave suggested, if it still won't start but still backfires, my next guess would be that the timing chain sliped a tooth or two.
 
Ok does you know which way my rotor cap should be pointing on my engine. Is it toward the firewall or the radiator that is the only places I directions I can the destributor to sit in when it top dead center. Some one told me the rotor should show 5 oclock if you look at it like a clock but I cant get it to drop in there. Or is it just time for a engine rebuild
 
Shouldn't he try to get it to TDC on the compression stroke of number 1 like I suggested and see that the rotor is pointing at the #1 wire and ensure the wiring for the timing / firing order continues from there?

I think your timing is off, but hoping it is not as Old Dog and Busa suggest. As the timing chain is kinda a pain...


:chug:
 
JR74CJ5 said:
Shouldn't he try to get it to TDC on the compression stroke of number 1 like I suggested and see that the rotor is pointing at the #1 wire and ensure the wiring for the timing / firing order continues from there?

I think your timing is off, but hoping it is not as Old Dog and Busa suggest. As the timing chain is kinda a pain...


:chug:
Click to expand...
The compression stroke so your saying the number one piston will come up once easy and then on the hard stroke is when I want to set my timing and all. Did that make sense. I'm turning the engine by hand to get number one up to tdc
 
Travis4x4 said:
The compression stroke so your saying the number one piston will come up once easy and then on the hard stroke is when I want to set my timing and all. Did that make sense. I'm turning the engine by hand to get number one up to tdc
Click to expand...


Yes with spark plug out you will feel the compression stroke, or hear (like a hisssss) it if can't put your thumb over while turning, and once you know its that stroke, feel with a thin "screwdriver etc" the top of the piston coming up. at the peak of it's stroke, should be top dead center of number 1 cylinder (please someone correct me if I am way off, but this is how i remember it...) :cool:

At that point, remove the cap, and take note of where the rotor is pointing. Should be where the number 1 wire is hooked up on cap (or close to depending on how accurate your top dead center is), if not change the Wire on the cap to be # 1 it's pointing to and correct the firing order from there forward, let's see what that does...
:chug:
~ JR
 
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