Solex carb issues

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Old manwithaCJ5
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Solex carb issues

Post by Old manwithaCJ5 » Wed Dec 02, 2020 8:59 am

Greetings G503 members,
I just joined this Board yesterday. I sure hope some of you folks with Jeep CJ5 experience can help with my latest roadblock.
First a bit of history with this car. 6years ago, my son brought it literally out of a barn and had it towed home. its a 1959 CJ5 with a F134 engine. Engine compression is not too bad between 90 and 100 psi. So far we have replaced just about everything...brakes...body...wiring...ignition...radiator and windshield (from a 1968 CJ5). Rebuilt the steering box and new steering wheel and horn. Removed the engine oil pan to scrape congealed oil/water glop out.

That brings us to the latest challenge. Fuel delivery.....I replaced the engine driven fuel pump with a new single stage one from Kaiser....worked fine for 30 seconds, but not the pumps fault....works if I pump it by hand. Tried a AutoZone pump, but no luck, same result. The one from Kaiser looked as if the cam was riding on the extreme forward part of the pump lever. Tried swapping a few times, no luck (getting pretty good at this pump replacement).
In desperation, I installed a Mr Gasket mini fuel pump and filters I also installed a pressure gage on the hose at the carb inlet. I am getting about 7 psi at the carb, which I read from some in this Forum is too high, so I am considering a Holley fuel Pressure regulator to dial it back to 2 or 3 psi.....will do this tomorrow.

Which brings me to my question. when we pulled it from the barn it had a pretty cruddy Solex on it, and would run only after repeated priming, and heavy choking. We replaced the Solex with another (maybe we need a Carter?) but still the engine only ran after the priming routine and only with full or almost full choke.
Now with the electric pump I am not too sure if I am getting any fuel through the carb (I checked the filter beneath the inlet port and it is clear), because even with the priming, it only runs for a few seconds and does not run even with the electric fuel pump on.

Could it be that the 7 psi pressure is causing the Solex to close off (somehow) ? No sign of fuel leakage at the carb, not sure if it is flooding, but I dont think so, because it burps just fine if I switch back to the priming routine.

Any ideas ..... or just give up and try a Carter?

Old manwithaCJ5


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dpcd67
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Re: Solex carb issues

Post by dpcd67 » Wed Dec 02, 2020 2:01 pm

Welcome.
Yes the Solex need low fuel pressure; I have installed regulators for them.
As for your pump, if you had got it from Ron Fitzpatrick, the guy who pays for this great site, you would be assured it was a good one. This where all the top quality parts come from. RFJP sells both carbs and pumps for the CJ5.
Also, your cam lobe might be worn off; it happens.
Is your carb a known good one?
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parker007
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Re: Solex carb issues

Post by parker007 » Wed Dec 02, 2020 3:46 pm

get correct fuel pump and rebuild your solex.

Old manwithaCJ5
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Re: Solex carb issues

Post by Old manwithaCJ5 » Wed Dec 02, 2020 3:48 pm

It's a Kaiser Solex....
I thought the cam lobe being worn off was only urban legend....I suppose not....
All electric from now....
Is it possible for the solex to refuse fuel past the main metering point if pressure is 7 psi?...
.

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Re: Solex carb issues

Post by Wolfman » Thu Dec 03, 2020 5:54 am

Welcome to the G, Old Man. :D
I fit the category myself.
Several things come to mind.
This carb. is untouched and has been setting for 6+ years ??
I would be surprised if it did work.
Where did the replacement carb. come from ?? Was it functioning ???
Has it been setting too, or off a running engine ???
Fuel pressure 7 PSI. That is plenty. With a gauge connected to the end of the line.
That is a static reading. Pressure with no fuel flow.
I have a tee fitting arrangement, I made. The original line connects to a brass tee. A looped line circles around and connects to the carb. from the other side of the tee and the gauge is connected to the side of the tee. This set up lets you test fuel pressure in operation instead of just static.
Short story.
Had a CJ-2A once. Similar to the CJ-5 fuel system. Jeep had been parked for sometime because the owner could not keep it running and gave up. The engine would start with some coaxing but shortly die. Brought it to me. :roll:
Fast forward.
Turns out the fuel tank had some kind of what looked like fine sand in it. ???
The sand stuff had been sucked into the fuel line, out of the tank, and collected in the lowest part of the fuel line, to the fuel pump, just below the fuel tank.
This stuff moved in the line like sand on a beach with the incoming tide. When the engine was running, the sand would shift and block the line but when the engine died, it would shift back and settle out. At first there was fuel flow but the flow shortly stopped. Would do this over and over.
Caught on to this and tried blowing the line out. Same thing. air flow at first and then stopped. Over & over.
Finally replaced the line. Put an in line filter at the tank. That got the jeep running and could be driven but the filter shortly stopped up. Dead again. Finally replaced the fuel tank. As far as I know, the jeep is still going.
The reason I made the tee thing. To check pressure in actual operation.
Later, I cut the old line up, looking for the blockage. That is when I found the sand.
If you take the line loose from the carb. and crank the engine, with a can under the line, do you get a good shot of fuel with each pump stroke ???
One more thought. Didn't the fuel pumps with a vacuum boost have a spacer plate between the pump and block ???
Now you have gone back to a pump that maybe don't need the spacer ???
If too high a pressure was the problem, I would think going to a lower pressure electric pump would have solved the problem. Instead, sounds like things got worse.
Mike Wolford
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Comm./Inst. SEL
AOPA ( 50 yrs)
EAA ( 49 yrs)
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Old manwithaCJ5
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Re: Solex carb issues

Post by Old manwithaCJ5 » Thu Dec 03, 2020 8:47 am

Thanks for the info and experience.
Recently replaced the fuel tank and lines ..... had problems with the engine driven pump, and went electric....lots of flow at the carb inlet and gage says 7 psi.
Just got a 1-4 psi range regulator and will install it today or tomorrow.

Solex is 6 years old from Kaiser. Never did work well, Jeep and would only 'run" after extensive repeated priming, and with the "choke" full on. Since the fuel pump was dead all the time, I am pretty sure it was just running on what the carb could suck out of the tank under venturi vacuum.

So I will install the regulator and see what happens.

I seems like no fuel is getting through the shutoff valve to any of the internal fuel distribution circuits.
I see a Carter YF in my future.....a real choke which has butterfly and an acceleration pump which is (of all things) a pump. At that time I might try rebuilding the Solex....then again I just might throwing it as far as I can into a junkyard.

'Old man"

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Re: Solex carb issues

Post by Wolfman » Thu Dec 03, 2020 11:29 am

Never been a Solex person but, that is personnel preference. A lot of folks like them.
When they work, they are great !
The Solex carbs. I have been around are the newer version. Not real familiar with the older Kaiser version you have.
As you said, no choke plate.
The choke or enrichment circuit is a by pass around the throttle plate.
For the enrichment circuit to work, the throttle plate must be closed. Opening the throttle defeats the enrichment function.
Engine is started with the throttle closed. Choke out. Allowed to warm up a bit then the choke closed. Hopefully, you have lift off.
Should be an accelerator pump that squirts fuel into the venturi when the throttle is opened.
You may already know this.
My guess, the accelerator pump may be working or at least partially working. As is the enrichment circuit, but the idle and main jet circuits are partially or completely blocked.
You can fiddle with the carb. Pump the accelerator and pull the "choke " on and get the engine to fire but when you try to give the engine any throttle, it dies.
Close ??
Still don't know where the second carb. came from or it's condition.
This engine have a vacuum advance on the distributor ???
I have seen problems with this. Cranking the engine, the vacuum advance is retarded and there be spark, but as soon as the engine starts or tries to and the vacuum advance moves the point plate, you lose spark. Ground problem. Rust or corrosion between the moving point plate and the plate it is mounted on.
Also, along the same line, the braided wire that connects the distributor terminal on the distributor body to the points is bad. When the wire flexes, you lose spark.
Engine dies. Point plate moves back and you have spark until the next attempt.
This will drive you crazy !!
Mike Wolford
CJ-2A
VEP GPW
Comm./Inst. SEL
AOPA ( 50 yrs)
EAA ( 49 yrs)
4th Inf. Div. - 5th Inf. Div. - 2nd Armor Div. - CIB

Old manwithaCJ5
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Re: Solex carb issues

Post by Old manwithaCJ5 » Thu Dec 03, 2020 1:08 pm

The carb sort of worked over the last year, but having some challenge now. Fires and runs as long as I am dribbling gas in the carb....i.think ignition is ok, but have to check timing again.
My son and I had ot running g on choke 2 mo this and drove arround the neighborhood....but it was rough.
I am going to recheck the fuel lines and carb inlet fittings for gunk, install the regulator and pressure gage and try again.
I was pretty goog with carbs 50 years ago, but the Solex operatipn is confusing. Might try a rebuild just to figure out what the fuel circuits are....as well as look for gunk...
Thanks,
Will let you know if it gets any netter...
Old man

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Re: Solex carb issues

Post by Old manwithaCJ5 » Fri Dec 04, 2020 12:28 pm

Ok, installed the regulator and pressure gage. They seem pretty good at what they were designed for...can fet down to 2.5 psi.
Engine still requires prime to start, and I can even make it run if I use a hand squeeze bulb and sort of dribble it in.
After 15 minutes of this with no luck, I decided to prime it, turn the fuel pump on, tap the acceleration pump a few times, open the throttle and hit the starter. To my surprise, it kicked over and reved up smartly, but if I persisted I think I heard a engine knock.....not a backfire, more like per ignition. So I know that fuel is able to get through the Solex.....beginning to think next step is ignition timing.
Need to get another timing light, my 50 year old one seems to have given up the ghost...
Keep in touch, I think I am getting closer.
Old man

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Re: Solex carb issues

Post by Wolfman » Sat Dec 05, 2020 5:16 am

Getting better.
Sounds like an old Harley. You better know the starting technic or get use to walking home.
Let us know.
Mike Wolford
CJ-2A
VEP GPW
Comm./Inst. SEL
AOPA ( 50 yrs)
EAA ( 49 yrs)
4th Inf. Div. - 5th Inf. Div. - 2nd Armor Div. - CIB

Steve Webb
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Re: Solex carb issues

Post by Steve Webb » Sat Dec 05, 2020 12:45 pm

Look for a video by Scoupilot on setting timing with a vacuum gauge. He has a site oldjeep carbs with good stuff on it. Here is video


https://www.youtube.com/watch?v=M3UZBKZoIWY
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