Strange no start this morning

[Turbogus]

Since I got 'BB' she's been running fine save for a carb fire early on with an Edelbrock Carter AFB clone. Just this morning though she didn't want to start. The starter motor spun up fine and the motor after a short while seemed like it wanted to run but failed to catch. I removed the fuel filter and it was clear (no surprise as I replaced it a few months ago). Tried some starter fluid and save for running rough (under the influence of the starter fluid) she never got to running. Prior to this problem 'BB' showed no signs of this issue.

In the brief time I had during my break at work I slopped together the fuel lines to the filter knowing I'd have to reorient the lines when I saw

the direction of the fuel filter reversed. Now this thing has been running fine for over four years but I wonder if this may partially be the cause.

WIth the "I" terminal disconnected on the starter solenoid I wonder if this may also be the cause. I initally diconnected it on account of the starter running on and on (likely due to my gorilla arms overtorqing the battery connections to it).

 

[69jeepcj]

Did you get her going?

 

[Turbogus]

No start yet but here's a little background....
About 6 months ago a no start (at starter) problem arose. Using the DARS chart I detirmined that the solenoid was at fault. I replaced with a Streak solenoid that I mounted up and with the "I" terminal attached. Fisrt startup and the starter refused to disengage even after key off. I disconnected the battery and checked the connections. I found that by removing the "I" terminal the starter would disengage after startup as normal. I later learned from this forum that when I overtightened the battery connections to the solenoid I must've internally spun the contacts to the point they made contact.
Overnight I got to thinking about this and I may go with another new solenoid taking care not to overtighten the connections to the battery and starter. All that being said I ran peliminary tests using DARS I ran from Chart 1 "Ignition Coil Primary Circuit"
1. Key on connected voltmeter to positive terminal at coil and to ground. Voltage Acceptable 6V +/- .5V Result 6.1V
2. Suspecting the Coil I ran the "Coil Test" checking resistance between the two poles of the coil. Acceptable limits 1.13 to 1.23 Ohms at 75* (1.5 Ohms at 200*) Result 1.8 Ohms

By the DARS chart Coil Test I'm supposed to replace the coil at this point. Noting the starter solenoid, I recently had 'BB' in a trusted shop for a leaky power steering pump and subsequently noticed the "I" terminal was in fact reconnected

I think I'll still start with the solenoid, IF I can find another Blue Streak in this consumer desert.



I like SMP Blue Streak as they have that nice copper foot making for better continuity and generally much better construction than many others.

 

[Turbogus]

Last night, with the help of my hausfrau, we did the Secondary Circuit Check encompassing the following;
Disconnected coil wire from distributor and held wire within 1/2 inch of engine block checking for spark. OK
Removed spark plug wire from #1 and in similar fashion checked for spark. OK
Checked for fuel problems. None found
Unable to check timing without motor idling.

Ignition Coil Primary Circuit rechecked Ignition on 5.9V. Within limits
Turning Ignition to start 10.4V Outside limits Batt. voltage 12.4
Checked for short or open in "I" wire to starter. OK
Solenoid OK (starter turns) and "I" terminal live (for the time being ruling out the starter solenoid)

We stopped at Step 4 ~ time for dinner will take up again tonight.

 

[69jeepcj]

Im thinking coil.

 

[Turbogus]

Hopefully NAPA got my FD476 Blue Streak in last night, will check this morning.

 

[Turbogus]

The readings are closer to ideal but the Coil was not the exclusive issue. Got through Chart 1 Step 4 of the DARS last night, Voltage remained at 10.4V after removing the "I" terminal. I then connected a jumper from the Negative side of the coil to the negative battery terminal and I did get voltage drop to 5.7V.
Moving on to Step 5 checking the continuity between the new Coil negative terminal and D4 on the four pot Ignition Module and it took some serious probing force but I did get solid continuity.
By the DARS chart the next step is to replace the Control Unit i.e. Ignition Module.

I got on top of the motor last night with the help of a step ladder and noted that Pump Jets (accelerator pump) were supplying fuel to the primaries on the AFB.
If I can find the time going to act of JH's recommendations of checking TDC.

I'll continue posting results here as the occur.

 

[69jeepcj]

.seems unlikely to be the ignition module. Every time I have had one go out, I had no spark (just hate ya to waste money). You have spark! Then again it may be working but with low voltage, have had a coil do that before. I think you may have a voltage issue and not a faulty part. It seems from post #4 that you lose voltage when you turn the key all the way to start? May want to check voltage at both end of the power wire from batt, to ignition switch, to dist, to coil, to ignition module, to starter, both with key on and then while cranking. You may want to give greg a shout, he seems pretty good trouble shooting electrical issues. Mean time, i'll keep thinking.

 

[Turbogus]

From another forum I was reccomended to check static timing. Working only half a day today I hope to get to it, the on to rebuilding the AFB. as I'm not fully satisfied that it is an electrical issue since 'BB' will chug chug run on Starting Fluid.

 

[greg92jeepxj]

I heard my name . While waiting for a friend to show up for some on going maintenance to his ride , I caught the latest of dilemmas to Bkack Beauty. Confusing as it is , do you suppose Black Beauty's electrical is losing voltage from cranking to run supply to the solenoid ? You and 69jeepcj are on to something and wondering if there is a drop of voltage for the ignition switch to the "I" terminal of the solenoid. This is just a thought but if the ignition coil is losing saturation intermittently , the supply needs to be checked if the 12 volts is being lost at any point , possibly to ground ? I know your very careful in your installations when it comes to wiring and electrical but thinking this possibility needs to be eliminated before going on. You mention starting fluid being used to diagnose a potential fuel delivery problem . I can't remember if your fuel system has a pressure regulator plumed in to check pressure. There is no resistor wire to the coil negative since your running HEI so I'm thinking first if a meter can be installed in line from the ignition switch feed from run to the coil negative. Of course this would work ideal with the engine running and that's tough to do right now. But I feel that it needs to be confirmed if there is no loss of voltage during run . Trying to follow along with what has been done this far in your fuel and ignition checks as I know your very thorough . The only mods I'm familiar with on your jeep,were to the HEI install. Wouldn't it be sweet if we found out all that's wrong is a faulty column switch ? But that's too easy . Guess that why my idea of pluming in a meter between the run position and the coil came to mind. Also , to the best of my knowledge , the jeeps wiring harness is basically stock with no resistor wiring in the coil curcuit since HEI is being used but hoping all else is healthy as I would think since your very thorough at building electrical . This is what makes it difficult to figure , knowing your on top of your game and would certainly not over look adding in what is needed for the system to work right and trying to figure what went wrong. Now I know why fuel system problem comes to mind . Ilł respect that since I've come to respect your work and would never doubt. I'm decent at electrical ( thank you mr. 69jeepcj ! ) but I'm still working up to shining your shoes mr. Turbogus! Hope I may be of assistance on BlackBeauty as I've a soft spot in my heart for CJ's and we must do her right !

 

[superj]

so you have spark when cranking and holding wire to engine.
you have fuel down carb but runs when start fluid us used.
and you know air is entering engine through carb.

your key note is the fact that it ran on starter fluid. your carb is having issues.

"I removed the fuel filter and it was clear (no surprise as I replaced it a few months ago). Tried some starter fluid and save for running rough (under the influence of the starter fluid) she never got to running. Prior to this problem 'BB' showed no signs of this issue."

that means everything else is good enough to get her started. you have fuel going in when when you pump the carb.

"I got on top of the motor last night with the help of a step ladder and noted that Pump Jets (accelerator pump) were supplying fuel to the primaries on the AFB."


maybe you have a vacuum leak now and its enough to keep the jeep from starting? any hoses knocked off? what type of spray was coming from the carb when pumping the accelerator linkage? two solid good streams or just some fuel? you need two solid streams.

 

[greg92jeepxj]

As per SuperJ's post , fuel pressure and accelerator pump check will be needed to verify but mainly the idle circuit needs to be confirmed if pulling fuel . The accelerator pump fills from the float bowl so it will pump fuel if good but that will not help out to get the engine to start and idle since its vacuum in the first place that pulls fuel through the idle circuit . I'm sure your no stranger to carburetors but would you agree that fuel may not be reaching the idle circuit ? A quick and dirty test is to pull the idle mixture screws out to see if fuel squirts out after initial cranking to build pressure. Once there is pressure in the idle circuit , you can try to plug the ports with small plugs that will shoot out upon cranking . Pressure will drop after that but fuel will,pour out so please be careful. This isn't my favorite way to check a carburetor but I had to do it once when a friends car wouldn't start and spark was good and fuel pressure was good from mechanical fuel pump. It wound up being a carbonated port under the carb and power piston wouldn't close so idle circuit pressure dropped . I know this is an AFB carb and not a Rochester but it's still got an idle circuit and metering rods. Maybe something's up in that area ?

 

[greg92jeepxj]

I tried to follow along on your ignition system testing . Your primary seems ok for voltage delivery to coil . From your last test , you had to ground the coil negative to get a reading ? Already it sounds like the coil needs a better ground . What is the voltage reading for key on no crank from the coil negative without the ground you applied ? Also , I mistakenly called your distributor an HEI but I saw the photo and you've got the standard electronic ignition for that engine ? Be that as it may , we still need to know what the coil is being fed in run position . Got to be sure the solenoid relay is doing its job. Read your posts about relay issues , this comes to mind . That was why I suggested to check voltage from the ignition switch but it seems it's more critical to check run voltage from the solenoid "I " terminal to coil. After all , this should be what feeds coil from run . It seems your "s" terminal is putting out voltage during crank.

 

[JPNinPA]

When you did all the wiring clean up, did you replace the battery power and grounds?
Your engine is grounded as well?

 

[69jeepcj]

It is possible the timing chain jumped a tooth. If you don't have a timing light, or cant keep it running long enough to check the timing you can bring Betty to TDC then pull dist cap, while turning the crank (by hand or wrench) one direction, watch the rotor, as soon as it moves, stop! turn motor in the other direction, watch rotor again noting how much you have to turn the crank before rotor moves. The crank and rotor should move together, any movement at the crank before the rotor moves is slack in your timing chain. An inch of movement is A LOT of slack, Been there!

 

[greg92jeepxj]

I agree that since black Betty has developed morning sickness it's time to check her health. I'm not good with engine math but I understand that an engine's piston will reach TDC a certain amount of degrees on the crank while the crank is actually rotating toward 0 degrees and The piston stay there until a certain amount of degrees after when the piston begins to move back down the bore. My point is it needs to be verified that this certain amount of degrees BEFORE and AFTER TDC the piston movement is still correct from its last timing chain install. More so , we got to be sure it's consistent and hopefully not jumping a tooth. It's sad that all these checks may have to be employed on a fresh engine but I think it's better to confirm that valve timing is correct or not since the engine won't fire . It may not be necessary to obtain the spec degrees of piston travel in degrees before and after but it can't hurt to know if theses measurements are consistent. Something's gone wrong and I'm prompted now to say back to the drawing board. If valve timing is found to be right , God bless , no tearing down to the chain. But valve timing should at least be verified. Then we could at least be sure that the rotor is hitting on #1 consistent. Then we could go on to checking over electrical as we wanted . It is just strange for this to suddenly happen after the engine was fine . Prompts us to want to know , could it have jumped time ? After reading the entire thread again , this is on the back of my mind. Electrical checks next .

 

[Turbogus]

Well fried the remote trigger starter I think but in pulling No. 1 plug (then 3,5 and 7) they looked to be fuel fouled. I ran 'em through my old Harbor Freight spark plug sandblaster thingamajig and followed up with a wire toothbrush and tested for spark at the plug gap ~ pritnear as bright as a welding arc. Pulled the AFB and drained the fuel, letting it air out while I was at work the other day. Got an Echlin rebuild kit that I hope will have correct gaskets and parts.

Well I got into the AFB last night and was surprised how loose most of the screws were, all of the air horn to throttle body came loose with very minimal effort. After seperating the two I found two of the four Main Metering Jets were MIA !

Also I found some fine debris in the bottom of the float bowl (accelerator pump side)



With the help of my wife's sharp eyesight we detirmined that the existing primary jets are 395's indicating .095 which on the Carter scale is about 2/3 of the way up from smallest size (.054 - .110).
Prior to this no start situation, the spark plugs were burning fine with a light brown color.

 

[greg92jeepxj]

Well it sounds like you got hot spark . Cheers. Whatever the history of any previous disassembly of the carburetor is , is past tense . The missing parts obviously will be acquired and reassembled. That is the answer to the overly rich condition . Looks like you've got it nailed and at least you'll resolve any issues with the carburetor as you've been wanting to do since you've suspected issues with it. I believe after the rebuild and tuning in the idle mixture you'll be able to determine better if metering rod swap will be necessary since the engine rebuild. That could open a whole new tuning session as you'll have the ability to swap venturi's if need be. The current CFM output is probably able to cover your torque/hp needs with the current displacement but it's nice to know you have that option. I see some tuning in your future !
BTW , the pictures show clearly that the misses were mini backfires due to the over rich condition as the Venturi bores and throttle blades are carbon caked. It seems you've gotten to the bottom of this high speed miss that has plagued you so long . Looking forward to good news soonest as Black Betty hits the road again soon !
Hoping there will be no concerns regarding valve timing , but I know you'll want to get 'er running first and see what vacuum it pulls if initial timing is correct.

 

[Turbogus]

With regard to the hand cranking the motor I've got steady motion at the rotor without any indication of erratic motion indicating a broken tooth. I know what this looks like from a '69 Pontiac LeMans I once had with one of those OE 'silent running' timing chains that went kaput, and the rotor movement was very erratic.

 

[Turbogus]

I've cleaned up the Throttle Body and Air Horn using Carb Dip and Carb Cleaner (spray can) now it's on to the small parts, much of it is coated with a very fine soot that I can only assume is due to the starting fluid since the plugs looked fine a couple of weeks ago.