One bank dead on V6...

I was tired of seeing oil, so replaced the cyl head , Intake Manifold (twice) and Exhaust Manifold gaskets. I also swapped in a new rotor and cap onto my 71 CJ5 with a Buick 225, Hedman headers and HEI ignition.

Upon first restart, I found the 2 front passenger side exhaust pipes cold, the rear most was just barely heated up. They have spark. I assumed it was a really bad vacuum leak from the IM, so redid it again.

Upon the latest restart, that entire side is cold and I still have spark. Driver's side is quite hot and runs.

When I modulate the throttle, I get a good spray pattern from the accelerator pump. Anyone have good tricks on determining if that bank's carb jet is clogged? Fuel... Air... Spark. This should be easy and I'm pulling my remaining hair out in frustration. Thanks for your help.
Update: Was running EF distributor cap for last year, have still not gotten to run properly.

 

Pic's of rotor and inside of hei cap would help for start. What are you setting your timing (initial) then total and what is your vacuum reading?

 

I converted a 77-8# EF HEI to OF years ago (Warloch FTW). The cap and rotor i swapped on for the tune up are the same as the units they are replacing. Part of this evenings diagnosis will be putting on the old ones just for verification.

Im at 6000' elevation and since I didn't rotate the dizzy, timing should still be in the 10-12deg range at idle. I have the Mr Gasket spring set (softest installed) and no vacuum advance for the last 3 years.

Cant keep it running long enough for vacuum readings as of yet.

Walking into the garage meow. Ill post the fix, hopefully it'll save someone some time someday, somewhere...

 

Sounds like wrong cap or it's clocked wrong or 180 out. I went through the same pain not long ago ... The drivers side cyls run right when it's off, but the pass side runs dead cold due to the fire not lining up with the valve train.

 

Had this happen one time and the cause was a stopped up jet on the passengers side of the carb. I diagnosed it by the fact when I operated the accelerator pump the engine would run smooth for a second or two.

 

Unfortunately the site didn't post my response from Friday, but here's what happened on the weekend. Still quite stumped. This should be easy and I'm at a loss. Please take a look at the photo link for a visual aide, the orange line indicates rotor direction.

http://public.fotki.com/jhnbrackett/jeep-cj5-parts/dizzy.html

Over the weekend I took a ‘from square one approach’ to verify all my assumptions to this point have been correct.

I removed & swapped the jets to verify one was not clogged. I did not blow out any passages. The #2,4,&6 plugs are coated with fuel after cranking. It really seems like an ignition issue.

Comparing distributor caps, I believe I’ve been driving on an EF cap for the last year. After swapping on an OF cap with the above orientation, I am still only able to get 3.5 cylinders firing. Cylinders #2&4 do not ignite, while #6 is barely warm. No other orientation has given me better results
I’ve reoriented the rotor 180 deg, moved the plugs one forward, even tried two forward, which just yielded backfiring. . The distributor has the correct 3 point stator and 6 unevenly spaced lobes on the reluctor ring for an OF configuration. I line up the reluctor ring at the wider lobe for TDC.
#1 is at the correct TDC and the rotor correlates to the below diagram.
A timing light indicates #1 is shown at 10deg BTCD while cranking.
There is a steady 12.4V supply to the coil.
The distributor cap I am using has the 4, miss, 2, miss plug style with 3 different lengths of tangs, which should indicate it’s an OF.

 

Where did you check for spark at on the cold cylinders? At the end of plug wire or at the electrode on the plugs? I had the exhaust manifold gasket replaced on my truck about a year ago and the mechanic cracked one of the plugs without it being visually noticeable. Just a thought. that's about as far as my knowledge/trouble shooting goes, electronically.

 

OK First off after reading this twice it is very confusing.......and seems like a moving target...........

This is Important............We need to establish some basic motor functions before you move forward........so go back several steps and establish that in fact you do have #1 at TDC by putting the Crank hub mark lined up with the marker on the cover at zero. With the valve cover off are both valves completely closed on #1 cylinder?.......can you shine a light into the spark plug hole and verify that in fact the piston is now at TDC? You can also slowly rotate the motor by using a long flex bar and socket on the crank to slowly rotate it back and forth while looking at the timing marks on the front cover of the motor and the piston........Pull the cap...........where does the rotor now point? If it is off............you need to rewire the cap in the correct firing order and rotation.........and No you cannot rotate the distributor.
You may have a valve timing issue brought on by a loose timing chain or it could have even skipped a tooth.........or your cap has somehow been incorrectly wired.

Have you checked your plug wires with an ohm meter? from the inside of the cap to the plug end. record the numbers.........longer wires should have more resistance........

More after you reply..........

 

This is exactly the symptoms I had. I was running a pertronix, and the magnet ring was 180 out giving me 3.5 cylinders firing, and a stone cold exhaust on the pass side. Something is up with your dist / timing, but I agree with tarry ... Same logic path I followed to get to the answer.

 

I will spell it out better then because I very much started from square one on this last attempt.

I took off the driver's valve cover. I rotated the engine to confirm opening of the intake valve on #1 cylinder. I then continued another 270-360 deg to achieve TDC of the compression stroke according to the timing marks. I did not remove a spark plug to verify the piston is actually at TDC, I'm under the assumption the harmonic dampener did not rotate.

With the engine at 0 deg/TDC, I installed the distributor. The vacuum canister points forward and almost hits the fan as expected. The distributor has 3 pairs of unevenly spaced tangs on the reluctor ring. I lined up the 3 pointed stator with the longer (clockwise from shorter) tang on the reluctor ring. It could need to be pointed to the shorter one, I saw no hints online (assumed this was the 'sync' aspect). I then installed the rotor. The rotor points in the direction indicated by the picture that can be seen at http://public.fotki.com/jhnbrackett/jeep-cj5-parts/dizzy.html. I have not seen a different part number for an oddfire (BWD D157) vs evenfire rotor. I have also marked out exactly which length of tangs corresponds to which cylinder position. All of the tangs show at least 1 point of arcing contact. I then installed the distributor cap (BWD C186) with internal coil. There is 12.4V across the terminals, the unit is now ready for operation.

Once I begin cranking with various choke settings, I get the driver's bank to fire up, with the #6 (passenger side rear) only about 1/2 the temperature of the other side. #2 & 4 show gasoline on the plugs and the timing light indicates they are firing.
Assuming I do not have a vacuum leak on those 2 cylinders. Assuming I am receiving proper power to the dizzy with my small gauge wire. My orientation should work. The #1 cylinder fires as expected and indicates the appropriate advancement on the harmonic balancer timing marks.

I have verified I have an OF cap for a 75 Buick Skylark (BWD C186). I tried starting with the rotor 180 off from it's current position. Moving plugs forward 1 made no difference and threw off the timing light. Moving plugs forward 2 gave me a backfire. I have even swapped plug wires from side to side with no change.

Thanks for guidance.

 

Lets get the motor to #1 TDC first............forget about everything else for now......you must first have a starting position to understand and establish if the valve action / Camshaft is in time with the crankshaft and Pistons.......Lets try it again.....rotate and align the marks on the front hub / vibration dampener to the front cover as I mentioned.......... unless you have a degree wheel on the motor forget about all the 270-360 degree stuff. And why do you question whether or not the vibration / harmonic dampener does or does not rotate?............its part of the front crankshaft hub separated by a rubber ring to the outer ring where you will find a line / mark cut into it to time the motor...........Once the mark is on zero............look at both valves at #1 cylinder...........they both should be closed......and ready to fire.......again peak in the spark plug hole and see if you can see the piston @ TDC..........If when you align the marks up front and you have a valve open the motor is 180 degrees off...........rotate the motor one more turn or 360 degrees and align the marks and check the valves & piston location again...........if all is well pull the cap and check the alignment of the rotor and cap.......in its relationship to how its wired to each cylinder............

 

Remember there are a few different oddfire caps out there. I had same issue, wound up being wrong cap. Order all of them and trial n error it out. Hopefully your parts guy is nice enough to allow returns on wrong ones. It had me stumped for a bit.