Fuel blockage?

[titanjeff]

I tried to start my '85 CJ7 and, it appears, I might have a fuel block or pump issue.

I pumped the accelerator numerous times and never smelled any gas. I shot some starter fluid in the carb and it would start just long enough to burn that off.

It hasn't been started in a three or four months. Last time it started up fine. I replaced the fuel pump a couple of years ago.

I don't know much mechanics so wondered if anyone might have a suggestion of what I might try before towing it in.

Thanks.

 

[Torxhead]

For fuel sitting that long you could add a gasoline stabilizer to the gas tank. Remove the gas cap then use a hand pump to get the gas in the fuel line going up to the fuel pump inlet. Hopefully from there the pump will take over and the engine will start.

 

[Lumpy Grits]

:ww:

How much gas in the tank? Store with a full tank.
The fuel has drained out of the carb.
Let it crank, and pump the throttle a few times. It should light-off.
When was the last time the fuel filter was changed?
LG

 

[titanjeff]

Thanks for the advice.

I'm not familiar with a hand pump. I'll drop by the local auto parts supply and ask about it.

Yeah, I stored it with maybe 1/8 of a tank of gas. The filter was changed when the pump was replaced about 2 years ago.

I pumped the accelerator multiple times today. Usually, after sitting a while, it'll start but it might take 20 pumps to get it started. This time, nothing and, I assume, I would smell gas if it was pumping.

 

[Torxhead]

I would have suggested sucking fuel by mouth, but that stuff tastes terrible. Anyway, you just have to get the fuel in the line up far enough for the pump to take over. Sometimes raw gas down the carb can get the fuel to come up, but so far it hasn't worked. A hand pump can also test for any blockage, like on the pickup sock in the fuel tank. If so, blowing down the fuel line can temporary clean it off. The pickup sock is replaceable.

 

[titanjeff]

Thanks for the info.

How much gas can I safely pour down the carb? I put in about a cup of gas in it today and it started up long enough to burn it off. I wondered if I could add more to see if it might get the pump started.

No luck finding a hand pump today. I did find some tubing I ran into the tank and blew through but I doubt I generated enough air to unblock anything.

I also added some Sea Foam I had as well.

 

[mtnwhlr]

Thanks for the info.

How much gas can I safely pour down the carb? I put in about a cup of gas in it today and it started up long enough to burn it off. I wondered if I could add more to see if it might get the pump started.
.

I wouldn't use any more than that. Some times it takes doing it many times to get started.

 

[darkcloud]

Just finished fixing mine. Was a hard starter for quite some time. Fuel would drain back out of the filter and out of the pump. Two days and float bowl was dry and had to grind to prime the system. Sometimes 3 10-15 second wanks on the key. Then one day came into the garage and head out NO START. NO GAS coming into the filter. Replaced fuel pump and ran 3 days and quit pumping. Bad fuel pump. I think some of the issue was it got worse fast because I was constantly having to reprime a dry pump. I would replace the pump. It is the simplest and easiest solution. If it runs get the float bowl full. Shut it off then disconnect the output on the pump and run it into a gallon or half gallon clear jug and see how well it is pumping while the engine is running for a few seconds. IME Jeep fuel pumps are not one of their strong points.
To save on the starter after replacement and all is dry a small squeeze bottle filled with gas can be used to prime the carb. Dribble gas down the inlet hose/tube until the float bowl is full. Put it back on and clamp. Should start and run long enough to prime and fill everything. I hate open bottles of gas in case of backfire. Also on mine I can just remove the wingnut, washer and rubber gasket and dribble a teaspoon down the stud into the throat of the carb. Helps also against back fire and a disaster.

 

[titanjeff]

Though the pump is less than 100 miles old, I'm beginning to wonder.

Tried again tonight pouring about 3/4 of a cup of gas down the carb. I would pump the accelerator and it would fire right up, burn off the gas and die. Did it three times.

It looks like it's time to invest some more $$$ into the joys of Jeep ownership.

 

[Scorzany]

Get you a new fuel pump. NAPA one is less than $20. Take 10 min to change it.

You could also have a crack in a fuel line or fitting that is big enough to let in air. Can't pump air if it's large enough.

 

[titanjeff]

I'm still playing around with this. Here's what I know so far.

• Fuel pump seems fine as I started it up and had gas pouring out the line ahead of the filter.

• Replaced the filter.

• Can pour a little gas in the carb and it starts up until it burns off.

Any other ideas if the issue is blockage after the filter? Thanks.

 

[Torxhead]

So this could be a carb issue. There could be a blockage at the needle & seat not allowing fuel into the bowl. A good test would be pumping the throttle, looking down the throat of the carb, and looking for raw gas squirting out. No gas in the accelerator pump bowl means no gas in the float bowl. Then the top of the carb has to come off and look for any blockage at the needle and seat. Be careful not to tear the float bowl gasket. It could just be stuck from sitting. That's just my guess though.

 

[titanjeff]

It's the weekend which means I'm going to tinker a bit on the Jeep. I still haven't gotten it to start but want to try one last effort before calling the shop.

I checked the fuel pump by disconnecting the line from the filter and it was pushing gas through. Any ideas as to how much gas should be flowing? It wasn't a lot but I'm inexperienced in such things and through it should be sending a healthy flow.

The filter is new. It starts up when pouring gas into the carb.

If the carb is the issue, this is beyond my skill set. Is there any tricks which might help if it is blockage at the needle and seat besides taking off the top? I read on one forum to hit it with a rubber mallet to jar it loose. I'm not feeling good about doing that.

Thanks.

 

[Lumpy Grits]

Is the return line on your fuel filter at the 12 o'clock position?
Can you blow air into the fuel feed line that attaches to the fuel pump from the gas tank? Take the gas cap off before you try this............
You sure you have at least a 1/2 tank of fuel?
Go to NAPA and try another fuel pump.
LG

 

[titanjeff]

Is the return line on your fuel filter at the 12 o'clock position?
Can you blow air into the fuel feed line that attaches to the fuel pump from the gas tank? Take the gas cap off before you try this............
You sure you have at least a 1/2 tank of fuel?
Go to NAPA and try another fuel pump.
LG

GRITS! You're the man!

I go out to see the new fuel filter I put on is at 10:00 to the return line. I twist it around and my Jeep fires right up.

I had no idea it needed to be in that position when I replaced it. Mind telling me why it needs to be in that position?

Thanks for your help. If ever in Nashville, I owe you a brew or three.

 

[Lumpy Grits]

If not at 12 o'clock and the filter horizontal and at the same level or higher than the carb. The fuel goes back to the tank.
I do hope that filter is not in the factory location over the exhaust manifold.
That is a known source for engine fires.
LG

 

[Scorzany]

Ahhhhhhh the return line on the fuel filter not in the 12 o'clock position strikes again!

Good job Lumpy. You saved the day again! Don't know what most of us would do without you.

 

[titanjeff]

The filter I replaced was just a year old but don't remember if it was turned or not when I removed it.

Thanks again.

 

[Scorzany]

The filter I replaced was just a year old but don't remember if it was turned or not when I removed it.

Thanks again.

I always take a few pics before I work on something. Brakes, electrical, vac lines, etc. Saved me a few times from pulling my hair out.

 

[Lumpy Grits]

I always take a few pics before I work on something. Brakes, electrical, vac lines, etc. Saved me a few times from pulling my hair out.

Pics really help when your CRS, becomes CRAFT(Can't Remenber a Frik'n Thing).
LG