Jeep wont start

[Trujeepr]

I have a 86 CJ7 that has been sitting for three years and now i removed gas tank and replaced the sending unit cleaned out the old gas and new battery new fuel pump and it cranks but no start. the # 1 spark plug has spark but didn't check the others, please help

 

[Torxhead]

Verify fuel pressure to carb, sometimes air gets in the lines, Sometimes a few drips of gas down the carb can get things going.

 

[DHugg]

I have a 86 CJ7 that has been sitting for three years and now i removed gas tank and replaced the sending unit cleaned out the old gas and new battery new fuel pump and it cranks but no start. the # 1 spark plug has spark but didn't check the others, please help

My Dad taught me to first look into the carb throat to be sure the gas squirts when the throttle is pressed. Next, you gotta be sure the plugs are firing, as you've already done. Third, look carefully for a bad vacuum leak, and disconnect and plug the vacuum advance to the distributor. After that, you want to verify timing mark with a timing light.

At this point, he'd get technical with compression testing and a compendium of other stuff, including fuel pump pressure by disconnecting the fuel line to the carb and turning over the engine for 10-20 seconds to catch about two cups of gas to flow into a "Dixon-Mason Jar", as some of my Cajun friends term it.

I've had many occasions to follow his teaching, but it doesn't work worth a drat on a computer-controlled engine with sensors everywhere.

Another good reason to drive an old Jeep.

 

[Trujeepr]

My Dad taught me to first look into the carb throat to be sure the gas squirts when the throttle is pressed. Next, you gotta be sure the plugs are firing, as you've already done. Third, look carefully for a bad vacuum leak, and disconnect and plug the vacuum advance to the distributor. After that, you want to verify timing mark with a timing light.

At this point, he'd get technical with compression testing and a compendium of other stuff, including fuel pump pressure by disconnecting the fuel line to the carb and turning over the engine for 10-20 seconds to catch about two cups of gas to flow into a "Dixon-Mason Jar", as some of my Cajun friends term it.

I've had many occasions to follow his teaching, but it doesn't work worth a drat on a computer-controlled engine with sensors everywhere.

Another good reason to drive an old Jeep.

i don't the 1986's had much of a computer but it does, and I (with help of friend) found the inlet to the carb check valve for the floats was stuck closed. so tomorrow it should start.

i need to drive it again, i miss it

 

[Saddle Tramp]

All good advice above. If you have spark to #1 then most likely all is well but check the cap anyway just to make sure; replace the fuel filter too. The carb may be all lacquered/gummed up so the float can’t float so to speak and may need to be rebuilt. Also rather than pouring gas down the carb I like to use starter fluid as it will even make a flooded engine start. Heck, I once watch a couple of not-so-bright guys run a diesel road grader down the road for a mile on the stuff; one drove while the other ran alongside squirting the stuff into the air intake.

 

[Trujeepr]

All good advice above. If you have spark to #1 then most likely all is well but check the cap anyway just to make sure; replace the fuel filter too. The carb may be all lacquered/gummed up so the float can’t float so to speak and may need to be rebuilt. Also rather than pouring gas down the carb I like to use starter fluid as it will even make a flooded engine start. Heck, I once watch a couple of not-so-bright guys run a diesel road grader down the road for a mile on the stuff; one drove while the other ran alongside squirting the stuff into the air intake.

i do have spark in all cylinders, new plugs, new pump, i pulled the top off the carb and the floats are free moving, and i did spray starter fluid in there but nothing, just crank.

 

[Saddle Tramp]

i do have spark in all cylinders, new plugs, new pump, i pulled the top off the carb and the floats are free moving, and i did spray starter fluid in there but nothing, just crank.

With spark and starter fluid it should at least sputter. My next check would be the distributor; must not be firing at the right time. Find top dead center then reinsert the distributor.

 

[Trujeepr]

I got it running thanks to my brother-in-law and my neighbor.

now just clean up the water ports and buy a new thermostat, flush the system.

Change the oil.

:drool:

 

[gert]

congrats

 

[Trujeepr]

Here is My Son waiting to drive it.

 

[thiswontbetooexpensive]

The bandana has faded some, but the jeep looks great! Thats some nice pic you have there.

 

[Trujeepr]

Thank you, and other sun beaten things will need replacement soon

 

[TroyaCantrell]

What was the issue?

 

[thistle3585]

Yes, I would be interested in hearing the problem. It might help me solve mine.

 

[Trujeepr]

Here is the Laundry list of all parts replaced and cleaned.

Gas Tank removed and cleaned.
Fuel Tank Sending Unit.
Fuel Pump
Fuel Filter
Spark Plugs
Coil
Distributor Cap & Rotor
Ignition Module
Pickup Coil

i needed air, fuel and fire to start it.

The air part:
All the air hoses are good.

The fuel part:
The carb float and gas inlet valve to the carb were stuck closed, fixed and now fuel flow into the carb.

The fire part:
I started on the spark plugs, ignition Module, coil, then the distributor cap and rotor, after each replacement the spark got betterbut not good enough until the pickup coil was replaced then it started.

sorry for the long explain, but that was the order i did the work, and so far i spent $320.00.

 

[thistle3585]

Funny, I have replaced all those same things but mine is yet to start. I got to talking with a guy today and he said he bets that my new plugs are shot from having flooded it time and time again while trying to figure out what is wrong with it and that I probably have fixed the problem but the plugs are shot. I'm on my way to the autoparts store for new plugs.

 

[TroyaCantrell]

Funny, I have replaced all those same things but mine is yet to start. I got to talking with a guy today and he said he bets that my new plugs are shot from having flooded it time and time again while trying to figure out what is wrong with it and that I probably have fixed the problem but the plugs are shot. I'm on my way to the autoparts store for new plugs.

Doubt that flooding the plugs caused the to go bad. I have never heard of that. It's ceramic and metal, putting some gas on that is not going to hurt them.

 

[DHugg]

Here is the Laundry list of all parts replaced and cleaned.

The fuel part:
The carb float and gas inlet valve to the carb were stuck closed, fixed and now fuel flow into the carb.

The fire part:
I started on the spark plugs, ignition Module, coil, then the distributor cap and rotor, after each replacement the spark got better but not good enough until the pickup coil was replaced then it started.

sorry for the long explain, but that was the order i did the work, and so far i spent $320.00.

When I reworked the grounding system on my '80CJ7, the engine ignition system really perked up, and the carb electric choke began to function for the first time. I was surprised at how much the engine (a AMC 304 ) relied on good (mine is better than good, now) grounding. Now it never misses a stroke, idling or running at speed. It may be worth going over your ground wires to engine block, headlights, maybe a few more systems that you'd not like to stop working

 

[thistle3585]

Doubt that flooding the plugs caused the to go bad. I have never heard of that. It's ceramic and metal, putting some gas on that is not going to hurt them.

Yeah, it didn't work. Still not running.

 

[Trujeepr]

Well it's on the road now, passed emissions with very low numbers and now re-registered after 5 years.

Sent from my XT907 using Tapatalk 2