Help with tuning....

[berettajeep]

I need help tuning my Cherokee. I cannot get this thing running good for the life of me.

'74 401 had points, now it is HEI. 4 barrel Carter carb. With motor at temperature timing light is here which is roughly 750 rpms.




This is with the vacuum advance disconnected from the timed vacuum port ( If connected idle jumps up.) There is no change if connected to the manifold vacuum port.


[youtube]http://www.youtube.com/watch?v=EPGB3Fsg28s[/youtube]



Checking vacuum, I revved it up, it back fired through the carb and the RPM's jumped way up.

I loosened the distributor hold down bolt and brought the idle down to 700 rpm's. I shut it off and it dieseled for a good 15-20 seconds.

So anyone planning on visiting Astoria Oregon and want to take pity on me? I want to drive this thing ( and enjoy it.) but am getting frustrated with it.

http://www.fsjnetwork.com/forum/viewtop ... arter+carb

[haminawag]

When you disconnect the vacuum line from your distributor you need to make sure that vacuum port is plugged otherwise you've just created a massive vacuum leak, and you can't check your timing that way.

Your timing mark is indicating the engine is 15* retarded, it needs to be closer to 15* advanced.

Bring the #1 piston up to TDC on the compression stroke then pop the distributor cap, the rotor should be pointing forward, that will be your #1 spark plug tower on the dist. cap. Now, looking down at the distributor, and going clockwise the firing order is 1-8-4-3-6-5-7-2, connect those plug wires to their respective plugs.

Fire it up, reset your timing to 12* initial, then go ahead with your normal tune-up proceedure.

[berettajeep]

Still hating my Jeep..... Spent all day working on it. Bought me a fancy remote starter switch, took all the plugs out. Found what I believe is TDC ( Checked numerous times) Used my finger over #1 spark plug hole. When it was close enough, I would turn the motor by hand to get to TDC. Every time the timing mark was directly on TDC on the balancer.

Looking at my distributor, it was pointing a little before #1 plug wire. ( This is where it was yesterday, OP) So I took out the distributor and set it so it was a little bit after #1 spark plug wire. Put everything back together and nothing. Just cranks over.

Took everything apart again and check for TDC and it was the same results as before.

I have searched many a threads on this subject many late nights.


I just don't get it. I need to have someone stand next to me as I stare into the abyss that is my motor and tell me I am stupid and show me how it is done. It is probably something so simple but I can't see it or understand.


(Venting over, time to enjoy a beverage or two)

[haminawag]

The number one cylinder is on the drivers side farthest forward, I'm sure you know this already but sometimes ya gotta cover ALL the bases, right? And you're certain #1 IS on the compression stroke? Both valves closed? You can pull the valve cover to confirm this. If nobody was screwing around with the camshaft, and if the ignition system is correct, and if everything in the fuel system is okay, and if there is adequate air getting into the engine, and there are no mechanical problems, then it has to run. Fuel, air, spark, and compression are all that's needed for an engine to run. Go back over the basics, go slowly, cover all your bases, when you get frustated take a break and have a beer. You'll find the trouble, engines don't defy the laws of physics.

[jaber]

My question, does the harmonic balancer look ok? is it possible it has slipped on the hub? I have had this happen more then once, the rubber gets soft and it will slip and through your #s off.

Another thing to try is get a vac gauge and time it using vacuum. You can google that...

[haminawag]

But if #1 is TDC on comp. & balancer is zeroed, its ok, vac. timing isn't necessary. Besides, if his problem is vacuum leaks then he definitely doesn't want to vac. time it.