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Avis
07-26-2010, 08:47 PM
Alright, I need some advice/tips on what I"m doing wrong.. Got a 46 CJ-2A with a flat-head 4 cylinder in it. Original motor, was pulled and rebuilt and is now back in. I have spark, I have compression (90 lbs each cylinder) and I have fuel. Which leaves timing.. I"ll do my best to describe it, we have the timing gears correct based off the fact we have compression (right?) The only other thing is the distributor and that is set with the timing marks on the fly wheel to fire off cylinder 1. It turns over, it even back fired once yesterday. But now I"m completely out of ideas.. I don't get it! Thoughts? Ideas? If you need pictures I can post some or whatever you need.. just want to get her running..

fatbob
07-26-2010, 09:01 PM
Those timing marks to fire off cylinder 1 will line up twice.

Once on the exhaust stroke [ which may be where you are now, no good]

And once on the compression stroke, where you want it to be.


So line it back up, and pull off the valve cover and look at the valves on #1

If the exhaust valve is open or just closing, the you have found the problem.

Just turn it until both are closed and pull & reinstall the distributor.

It's an easy mistake to make, but an easy one to fix also.



good luck
Bob

djui5
07-26-2010, 09:28 PM
I'm a tard:

Avis
07-26-2010, 09:36 PM
I've checked that, the rotter will turn twice for every time it fires on one cylinder, right? So basically every other one. There is no valve cover, only way to even kinda see the valves is if you pull the spark plugs out. Which I've done many times to check them lol We've lined it up 3 different times (just tonight even) Where it was all lined up and on the firing stroke And the rotter was firing on cylinder 1 and the timing marks on the flywheel were lined up.

fjcarena
07-26-2010, 10:56 PM
The rotor should turn once for every two crankshaft turns, should be pointing at #1 on the compression stroke (both valves closed) If you have the distributor 180 degrees out, the exhaust valve will be open when it points to #1. You can pull the sparkplug out and put your finger over the hole and turn the engine over, when you feel pressure you are on the compression stroke and the rotor should be pointing towards the #1 plug wire. Hope this helps.

fatbob
07-26-2010, 11:35 PM
I've checked that, the rotter will turn twice for every time it fires on one cylinder, right? wrong, look at what posted

So basically every other one. There is no valve cover, only way to even kinda see the valves is if you pull the spark plugs out. My mistake, I thought wrong.

Which I've done many times to check them lol We've lined it up 3 different times (just tonight even) Where it was all lined up and on the firing stroke And the rotter was firing on cylinder 1 and the timing marks on the flywheel were lined up.

So line up the timing marks again and turn the rotor directly opposite from #1.

180* off.

What have you got to lose, because its not running the way you have it now.

After you do that, turn over the engine again and you'll see it still lines up on the timing marks, but it should run.
good luck
Bob

Desertdawg
07-27-2010, 08:21 PM
I posted this for another member who was having the same problem so I just cut and pasted the following:


I recently had the same problem after my L-134 was rebuilt on my MB.

This is what I did.

Make sure you have the distributor in the correct position and the plug wires are in the correct position.

You have the breaker points at .020..right ?

Most important is to determine compression stroke on cyl.1.

Easiest way is to remove sparkplug 1 and let someone hand crank it while you plug the sparkplug hole with your finger.

Feel how the air is pushing against your finger, do a couple of revolutions that you get the feel from a compression stroke.

Right after compression stroke, you will feel a suction.
Then as soon as you feel the compression stroke, stop turning.

Take a flash light and keep looking in the timing window nearby the starter.
Let your buddy turn the engine very slowly until you see the flywheel marks.
Stop at the IGN or 5 mark and do not turn the engine anymore.
If it would happen to pass the IGN mark, turn back the engine far enough and repeat.

Now unscrew the distributor locking bolt that you can turn it by hand.
Turn it counter clockwise until the points are closed.
Put ignition on and turn the dist clockwise and watch for a spark at the points.

Turn off the ignition and lock the dist at that particular spot where the spark appeared. Now the timing is 100% correct.

If this doesn't work, your distributor may be in the wrong position, therefore your wires will be on wrong. At TDC the rotor should be at the 5 to 6 oclock position.

If correct then the wires should be starting counter clockwise from 5 oclock,1,3,4,2. If not at the 5 or 6 oclock position then you will have to remove the oil pump and reposition the oil pump cam where the distro shaft sits in. Not a big deal but it can be tricky. Do what I told you first and if it still does not start I'll send you a link on repositioning the distro cam.

Good Luck!

Keep us posted on your progress.

Avis
07-28-2010, 05:07 PM
Alright, still won't run.. I don't understand. I followed all the procedures everyone gave and none of them worked. I know my flywheel is 180 out, so I figure out the timing by when there is compression in cylinder 1 OR I just fire off cylinder 2. (i've tried both) So if I go with cylinder 1, with 1 at TDC I then put the rotor on, take note of where it is at, and put the cap on then proceed to put the wires on in firing order of 1-3-4-2 putting plug 1 where the rotor is pointing. And still I get nothing.... ideas?

fjcarena
07-28-2010, 05:28 PM
Are you getting fuel, try putting a small amount of gas (like a tablespoon or two) down the carb and turn it over to see if it trys to run. Also check the plugs to make sure they are not fouled out.

Avis
07-28-2010, 05:33 PM
Yup, done and checked

fjcarena
07-28-2010, 05:54 PM
Did you try turning the distributor slowly while it was cranking both clockwise and counterclockwise. You said you have spark, is that at the spark plugs or the coil, I have seen rotors that arc to ground on the distributor shaft.

Avis
07-28-2010, 07:07 PM
Yes I did, I do have spark at the plugs.

fjcarena
07-28-2010, 09:56 PM
Does it even sound like it wants to run. I know you have spark, is it a nice blue/white or a dull orange spark. Is your coil wired up correctly, + to ignition and - to the points. It will usually run either way but the flow of the high voltage will be backwards,side electrode to center. Since you have fuel and spark the next thing I would check would be the valve timing, I have never worked on a flat head, don't know if it has a timing chain or gear driven. Is 90 lbs of compression normal for this engine?

willys one
09-02-2010, 08:31 PM
was wondering if you got this running?

CRAWLS
09-03-2010, 01:33 PM
If you have the oil pump gears in 180 off the motor will not fire. You have to take the oil pump loose and rotate the gear and get it to mesh in with the cam with the oil pump drive key pointed about 7 to the rear of the motor when viewed through the distributor hole. The #1 plug needs to be on TDC before you do this. The distributor only goes in one way since the oil pump key is slightly offset. When you have it right the rotor will point to the position of the #1 spark plug wire on the cap. That should be enough to get it to fire. Then adjust timing from there. There is a lot of info on the web about these motors. Go to the CJ3A pages or willys M jeeps and join those forums lots of knowledgeable people on there.

CRAWLS
09-03-2010, 02:38 PM
Here is a link to exploded views of the engine if you look at the oil pump section you will see what i mean. The distributor drives off the oil pump shaft and the oil pump drives off a helical gear that pins to the oil pump shaft. Because the slot in the shaft is offset it can only work one way, but it can be installed wrong. You have to mesh it into the cam gear just like a conventional type of distributor in say a small block chevy the concept is just backwards. On the conventional distributor the drive gear is on the distributor and the distributor drive the oil pump.

CRAWLS
09-03-2010, 02:38 PM
oops forgot the link

http://www.cj-jeep.com/cj3a/cj3aengineparts.htm