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No start, backfire thru carb

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SeeJayTwo View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 19 Apr. 2023 at 11:35pm
Just explaining why we have so much "off shore" merchandise. 

Edited by SeeJayTwo - 29 May 2023 at 6:18am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ron D Quote  Post ReplyReply Direct Link To This Post Posted: 20 Apr. 2023 at 4:25pm
Originally posted by SeeJayTwo SeeJayTwo wrote:

It's our own fault, like it or not.


Must have a mouse in his pocket.
It's definitely not my fault. LOL
1951 M38
1951 M100
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Post Options Post Options   Thanks (1) Thanks(1)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 24 Apr. 2023 at 8:06pm
I hope that Oldpappy will return. I made a mistake posting social/political comment that was bugging me. Should not have. 
I have no luck yet. ALL new parts. Still have spark, still have flame backfire.. No start. I understand can't be valves. I have triple checked everything three times. Got the timing hole cap off. Fires at 5 deg mark, compression stroke. My previous post explains all I have checked and this post says I have checked everything many times again. Cleaned all ground cables and battery hot cables. Points are sparking inside dizzy. points at .020. So this leaves carb. I have been squirting gas down throat. No gas in bowl. No fuel supply hooked up. I have done that on dozens of non willys motors. I don't see that not having a fuel tank or fuel pump installed could be the issue. Should run for a few strokes. But I have no other ideas. I have thought of everything...... But obviously I haven't.  Whenever I think of something electrical, I remind myself, I have spark at the right time, right stroke and have good compression. Tested spark lots of times to detect "wander" due to a gear problem. Held thumb over no.1 while watching it's plug spark. Used timing light in dynamic and static mode. Moved dizzy CW and CCW. Advance/retard.

I will install my new fuel pump and run a fuel supply into it and plumb to carb..........

I think that the robust flames are a clue. .they do show spark is igniting gas but the size of the flames makes me think gas is not going all the way into cylinder. Laying in manifold somewhat. Does anyone know what I mean?.....or am I nuts.

If gas is not getting into the cylinders, but the fumes are, then the spark ignites the liquid fuel in manifold and flames up out carb and down out manifold. That's why I have such big flames. But no cylinder combustion occurs. But why?. The motor does not know I'm the accelerator pump. Tried all combos of choke/throttle open and closed. Too much fuel? Not enough air? Giant crack somewhere?

The air/fuel mix is supposed to be sucked in from vacuum, sort of, created by piston. It it possible that having fuel pump off is causing a loss of vacuum or something causing loss? Water pump and fill neck are off also but they are water chamber items. Fuel pump is crankcase associated but not sure how that would matter either. Does this give any thoughts? I know I'm jumping the venturi but I've done it for 50 years. Is it true that a loss of piston vacuum would not show up on compression test?
No air filter or oil filter installed. I will check for a huge vacuum leak???????
Yes, I'm in the incoherent rambling stage but I'm desperate and depressed....any help is appreciated.


Edited by SeeJayTwo - 25 Apr. 2023 at 5:47am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RSR_MK Quote  Post ReplyReply Direct Link To This Post Posted: 25 Apr. 2023 at 10:03am
Have you checked the condition of the exhaust system. Sometimes older folks and jeeps just get plugged up. Dead

Mike

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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 25 Apr. 2023 at 3:42pm
Hi Mike,
I have the tail pipe disconnected at the manifold. Thanks for the thought. Keep them coming.


Edited by SeeJayTwo - 25 Apr. 2023 at 5:59pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Bruce W Quote  Post ReplyReply Direct Link To This Post Posted: 25 Apr. 2023 at 3:55pm
  The tail pipe does not connect to the manifold. The tail pipe runs from the muffler to the rear, or tail, of the vehicle. The exhaust pipe connects to the manifold. 
BW 
It is NOT a Jeep Willys! It is a Willys jeep.

Happy Trails! Good-bye, Good Luck, and May the Good Lord Take a Likin' to You!

We Have Miles to Jeep, Before We Sleep.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 25 Apr. 2023 at 4:01pm
OK
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 30 Apr. 2023 at 11:20pm
Still no start after installing fuel pump and tank supply. Backfire.  Still good spark and timed. Should I try a little starter fluid/spray? Something very weird going on.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Oldpappy Quote  Post ReplyReply Direct Link To This Post Posted: 30 Apr. 2023 at 11:43pm
Starter fluid isn't going to help.

It is out of time, or the valves are stuck. 

Stuck valves, ignition timing or cam timing being off, would cause the symptoms you describe, but stuck valves or cam timing being off would also prevent getting the compression results you reported.

That leaves only ignition timing being off. 

Explain how you determined it is "timed" correctly. 

 
If you can't get there in a Jeep you don't need to be there!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 30 Apr. 2023 at 11:52pm
A bunch of ways.
1. Put a white mark on 5 deg mark inside timing hole. 
2. Thumb in hole, watch plug spark at compression, look at rotor. Rotor at 5 oclock. set order 1342. CCW. Did that several times.
3. Tried rewiring dizzy starting at no. 4, then CCW 1342. Nothing.
4. Hooked up timing light to no. 1, shined light in hole, cranked with starter. all looked right. Then positioned timing light to shine in hole and hand cranked motor. When light came on, I looked in hole and was at 5 deg mark. Rotor at 5 oclock. Straw in No. 1 plug hole shows piston up.
5. Took off valve plate/cover. Rotated motor to see all valves going up and down when starter cranked. Then hand cranked to see both no. 1 valves close. Rotor was at 5 oclock.  5 deg in/near window.

Found little bits of metal inside valve cavity. Everything looked OK in there, didn't detect anything loose or crooked. If I had to guess about bits, not knowing Willys motor parts, I would guess keeper pieces. I really DO NOT know what they are. I saved them. Could have been there a long time after a repair?


Edited by SeeJayTwo - 01 May 2023 at 1:19am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 01 May 2023 at 12:01am
Tonite I installed pump and am sucking out of gas can. Moving dizzy CW & CCW a little.  Try choke and no choke. It has stopped flaming and seems like it's getting closer, not sure. heat riser loose so I added a vise grip plier onto flapper to act as a weight to keep flapper straight down. Tying everything I can think of, have to quit and wait for starter to cool down and keep changing battery. Checked all items above again. Never been this stumped in 50 years....but I've never been this old before.

I'm going to see if I'm flooding it or starving it. Will try gas in each hole and quickly put plugs in. 

I can try and get head off if that is necessary. I have to do something. I do have reasonable vacuum at carb horn. As I said, after I am getting genuine venturi, it seems to have improved and stop flaming out carb. Puffing like it's running but it's not. 
I have double checked ignition wiring using a "Ford" style starter relay vs ballast resistor vs coil. 

I am posting so much stuff hoping someone will catch my mistakes.


Edited by SeeJayTwo - 01 May 2023 at 1:22am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote cpt logger Quote  Post ReplyReply Direct Link To This Post Posted: 01 May 2023 at 4:06am
With out pictures, or better yet a video, it is hard to get a good idea as to what you have going on there.

OTOH, With those numbers for compression, the valves are just fine, as are the pistons rings, the head & it's gasket. 

Pictures of the "metal bits" would help. How big are they? Thumb sized or point screw sized? Smaller, bigger? Are they shiny and smooth or rusty and crusty? Are they ferrous? will a magnet pick them up?  Yes, they might have been there for years.

IMHO, You have a timing or spark issue. If the plug wires are 90* out of time, it will give you the symptoms that you are describing. CCW looking down from the top correct?

Sometimes the distributor does not ground well due to rust, crud, paint, or a combination of the above. Just for grins, try running a ground wire from the negative post on the battery to the distributor case. If your distributor cap clips are secured with screws, that is a good spot to ground the case.

IHTH, Cpt Logger.


Edited by cpt logger - 01 May 2023 at 4:08am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 02 May 2023 at 2:15am
Originally posted by cpt logger cpt logger wrote:

With out pictures, or better yet a video, it is hard to get a good idea as to what you have going on there. I can't take a picture of what is wrong. It backfires flames (now just a little puffing) and won't start. 

OTOH, With those numbers for compression, the valves are just fine, as are the pistons rings, the head & it's gasket. Agree, I think.

Pictures of the "metal bits" would help. How big are they? Thumb sized or point screw sized? Smaller, bigger? Are they shiny and smooth or rusty and crusty? Are they ferrous? will a magnet pick them up?  they might have been there for years. Yes Ferrous. one is ~1/8 "diameter" ~3/8 lg. Other 2 pieces very small. They were in rear most catch cavity.

IMHO, You have a timing or spark issue. If the plug wires are 90* out of time, it will give you the symptoms that you are describing. CCW looking down from the top correct? Yes. you say 90 deg, that is one distributor plug wire position. Is that what you mean? As opposed to 180 deg out.

Sometimes the distributor does not ground well due to rust, crud, paint, or a combination of the above. Just for grins, try running a ground wire from the negative post on the battery to the distributor case. If your distributor cap clips are secured with screws, that is a good spot to ground the case. I have spark.

IHTH, Cpt Logger. thank you, don't mean to discourage thoughts. I'll get some pix up soon.


Edited by SeeJayTwo - 02 May 2023 at 8:06pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thisoldwillys Quote  Post ReplyReply Direct Link To This Post Posted: 02 May 2023 at 5:50am
My thoughts after reviewing, intake is stuffed w gas. If I were you I would remove the carb and inspect intake, then exhaust restriction. Then start all over again w TDC initial start procedure 

One year at the spring reunion we had a bounty on starting a particularly troublesome L134. Literally all the best dudes couldn’t will it into running. In the final minutes on the last day, it was realized that it was almost hydrolocking and the intake was crazy flooded, it was running around the show parking lot moments later. 


Edited by Thisoldwillys - 02 May 2023 at 5:54am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WeeWilly Quote  Post ReplyReply Direct Link To This Post Posted: 02 May 2023 at 12:54pm
  Flooding were my thoughts also.  Many years ago when a car was flooded I would take out all the spark plugs and use a torch to ignite the fuel in each cylinder, it worked. Warning it does make a little explosion!

    Jim
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 02 May 2023 at 4:14pm
Way back I did mention I thought motor was stuck and I soaked the plug holes with oil and penetrating oil for weeks.  Found out it was the water pump that was frozen and belt held motor. I was happy. Many weeks later began to take water pump off, fuel pump off, carb off, Never tried any gas. This is after Willys sat for 25 years. Looking down the intake manifold I saw wetness. Just laying in maifold. I soaked it up and assumed it had to be my previous soaking mix. Couldn't be gas. I did read on here that someone said these motor sometimes have gas just laying in manifold. It seems like after I soaked up the manifold, it reapeared. Didn't think a whole lot about it at that time. Since then with all my troubles I thought about it and then kind of dismissed it again. I assume here in the hot SW that the gas I squirt down in cab will evaporate pretty quickly. The oil I used to "free up" the motor would not. It would sit on top of piston. When folks do that it gets burned off when motor starts. That why I mentioned starter fluid. Now that two of you mention flooding and lockup, I will revisit that situation. I will stop trying to start and take off carb and see if there is fluid in there and what it is. I'm going to rig up something with cloth on it to do a gun barrel clean out of intake manifold passages. Probably use old speedo cable sheath with rags attached or something like that.
What did the crew do to at the reunion to get that motor unflooded/unlocked?

EDIT: After writing above, I went out and checked plugs and piston. Brand new plugs had "soot" on them but it wiped right off. Not wet per se but I guess oil covered. Top of piston was black. I saw this way back. Thought is was hard coat carbon. This time today I stuck a thin blade screw driver in there and gently "scraped" top of piston. The .010 thick coating of XXX came off easily down to shinny piston top. This can also support the suggestion by a few members that the motor seemed fresh'ish. 
The coating on plugs and on piston top, when rubbed between my fingers I'm guessing is motor oil and penetrating oil scum. It spreads out on my skin. It's a dark thin "gell" of oil. Probably same in manifold, plus gas, but hard to notice with a black casting. I will try to clean EVERYTHING out now after I think it all over with help from everybody. What are the best methods?

I'm not sure how any of this would cause my trouble because I never heard of it and it is not carbon. I guess my soaking for weeks with motor oil and penetrating oil did all this? I probably did it 8 or 10 times over a few months trying to free up and get crank to turn. All the while it was the damn water pump. It seems that vaporized gas/air would still get there..... 
I do think I have, or had, the dreaded 2 or 3 different issues at once. 

No exhaust restriction. Exhaust pipe off at manifold.
I know timing is right. Right enough.


Edited by SeeJayTwo - 02 May 2023 at 7:56pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Oilleaker1 Quote  Post ReplyReply Direct Link To This Post Posted: 03 May 2023 at 6:00am
Buy a spark plug checker and see if the 4 plugs are actually firing. You can get one cheap at Harbor freight and then put it in your tool kit. Maybe your whole problem is fouled plugs??? 
Green Disease, Jeeps, Old Iron!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SeeJayTwo Quote  Post ReplyReply Direct Link To This Post Posted: 03 May 2023 at 6:38am
I have checked them many times. They are all firing at TDC compression. I have two plug checkers. I don't like them. I just lay the plug out and watch it. They fire without cleaning. But the oil fouling could be preventing combustion. So I'm planning on squirting gas into a plug hole, one at a time. Put plug back on and turn over motor. Then take plug out and spin motor again to let oil blow/pump out. Maybe it will, maybe it won't.  All this without coil hooked up. This is to wash out piston top/head. Interested to see if that cleans the pistons. If it does, it means there was a lot of oil left over. Then somehow clean intake manifold passages. Dry it all up and start the motor! I don't want to do the torch deal, my luck: it would crack something.
Nothing else makes sense. Even this idea doesn't make sense but I've have tried/checked everything else 10 times. I have to be careful not to "hydraulic" the motor with too much wash gas. I will take this procedure slowly.

Also, if there is a lot of oil in there it's from my soaking and it is contributing to my compression numbers.


Edited by SeeJayTwo - 03 May 2023 at 7:20am
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