Problem starting Jeep (1977 cj7)

[Rdavison39]

Need some help. Okay - so let me begin by stepping you through what I did......


1. Jeep starts fine and has for many years. Then I decided to do a few things to it.
2. Removed the air injection system and plugged 7 holes as a result with bolts (see #4 in pic). Remaining was a hose marked at #1 in the picture. I'm assuming I can just plug this (but haven't yet).
3. Removed air filter. Unattached 2 hoses. One that attaches to where you pour in the oil and another that attaches to the bottom of the air filter canister (see #2 in pic)
4. Accidently grounded the starter solenoid (#3 in picture). It sparked but I don't think I damaged anything


Then I went to start the jeep. Ran perfectly for about 7 seconds and then stopped. Cranked it many times and while it turned over perfectly it never started. So i'm thinking I somehow screwed up the fuel system. Its like whatever little gas was left in the line was used up and then when that was used up it stopped


Does anything I did above lead anyone to believe I did something (obviously I did something along the way)?


If not, where would you start next to diagnose the problem?


Thx
Ron

 

[Torxhead]

First think I would check would be the fusible links one coming from the hot line of the alternator to the starter solenoid and the other one coming from the starter solenoid and going to going to multiple locations Both of them are red in color off the solenoid. If you are not sure what a fusible link is I would suggest looking it up.

 

[CJ]

~~~If not, where would you start next to diagnose the problem?

I would start withe the basics, spark and fuel.

Busa wrote an excellent trouble shooting guide concerning engine start problems here -->> http://www.jeep-cj.com/forums/f99/engine-wont-start-troubleshooting-guide-19494/

 

[Lumpy Grits]

Squirt some gas down the carb. Does it try to start?
If no-You killed either the ICM inside the dizzy, or ign module mounted on the drivers side fender under with windshield washer bottle.
If it does try to start-Check you carb's float setting and go from there.
LG

 

[hdgapeach]

Plug any open hoses you have that may be a source for a vacuume leak.

Get someone to floor the gas pedal once while you look down the throat of the carb. If you see gas squirt, you're getting fuel to the bowl and the fuel pump is pushing fuel (I'm assumming it's still a mechanical fuel pump).

If all that is checked off the list, check for spark like mentioned above.

Gotta be one of the three; too much air, not enough (or any) fuel, or weak / non-existent spark.

No tools needed.......yet, 'cept maybe golf tees and a spark tester!

 

[Rdavison39]

Thanks Guys - will give it a shot tonight by trying/checking out your suggestions and let you know how it goes

 

[Rdavison39]

So I checked for spark and when I grounded the spark plug against engine block and cranked the starter there was no spark. Which explains why it doesn't start. So I guess its either the coil or the ICM or maybe even the distributor cap.

Any easy way to tell which one is the issue?

 

[Lumpy Grits]

Coils are kinda hard to kill. They usually act up when hot.
ICM's on the other hand can run when cold or not at all.
Dizzy cap and rotor are an easy eyeball ck and would be where I would first start.
IF you do buy a new ICM. Disco the POS(+)from your battery before you start the install. Don't buy the cheap ones either. Go to NAPA and get their best.
LG

 

[Torxhead]

Also, check for voltage at the coil and check connections.

 

[Lumpy Grits]

Especially if it's that DN horseshoe connector.
LG

 

[Posi]

Also, check for voltage at the coil and check connections.

I would start there first.
Turn the key on (not start), with probes on the positive post of coil and ground.
You should have 6v plus or minus .5v
If you do it will rule out any issues from the ignition switch to the coil.
Next with the probes in the same place have some turn the key to start or use a remote. Your meter should read battery voltage.

 

[Rdavison39]

Thanks for the tips. So here is where i'm at:

1. I replaced the Ignition control module ($120)
2. I also replaced the Voltage regulator even though i'm told this has nothing to do with spark

I cranked the engine and I have now have spark. So I thought alright, that was the problem.

Then after putting the spark plug I used for testing was screwed in I cranked the engine and same result.

So when I pump the gas I see gas squirt into the carb, when I crank the engine I see spark. So I'm at a bit of a loss as to why the jeep won't start and what to try next......

I did go through the thread offered by the admin on trouble shooting problems and they suggest I make sure fuel is being pumped. But if I see fuel squirt into the car when I put my foot on the pedal then I would expect the engine to turn over and start.....but there is no sign of the engine catching....

any help on where I should look next would be great.....

Thx

 

[Lumpy Grits]

Pour about 1oz of fuel into the carb.
She if it tries to start.
Is there any chance you moved the distributor's position when doing the ICM install?
Do you still have that horse shoe connector on the coil? They are well known for contact issues.
What mods have you done of late?
The VR has nut'n to do with spark-Do you still have the old one? If so. Put it back in.
NOTE-ANYDANGTIME you do any electrical work on any vehicle. Disconnect the POS(+) battery lead FIRST!
LG

 

[Rdavison39]

I'll try pour 1oz of fuel into the carb (I would try it now but i'm out of town).

I didn't remove the distributor cap when replacing the ICM - just unhooked the wires and plugged into new module

Not sure what the horseshoe connector on the coil refers to. I will have to take a closer look. I did also by a new coil but was only going to replace it if I didn't see a spark.

In terms of mods the only thing I did was remove the air injection equipment and plugged the 7 holes.

I am doing this without the air filter on.....assuming that is not the issue ??

As a mentioned before. The last time it started (after the air injection mods) everything started fine, ran for about 7 seconds and then died - like it was starved for fuel.