allis chalmers B initial startup problem

rosedale123 · Sep 12, 2014

here is my ordeal

new head, new intake manifold, new carb, rebuilt mag ( done right), new wires , plugs, oil

my test start did not goes so well. It starts and runs about 2 seconds. starts back up - for another 2 seconds.

compression is good ( 100 - all), good "suck" when I hold my hand over the intake while turning, valves adjusted cold to .013, good fuel flow to carb, plug plug our of carb andstill good flow. spark is great, timed cold with timing mark

Sounds fine for those 2 seconds. I can keep it going a little longer if I spray starting fluid into the intake. took the carb apart and blew out main jet - it was clean

Seems like it starves for gas real quick but this doesn't make sense to me

Can someone help me out - frustrated

steve(ill) · Sep 12, 2014

timing should be at TDC, not the fire mark. Will advance to FIRE after RPM advances... ?

cole in mo. · Sep 12, 2014

If you can keep it running longer using either, the problem is in the fuel.

tractorguy2 · Sep 12, 2014

It is not getting fuel. it might not be running into the carb fast enough. The needle could be stuck. The load adjustment might be set to lean.

Dick L · Sep 13, 2014

I have never had any luck blowing out the power jet with it in the carburetor when something get stuck and blocks it. The blockage will most likely come out the direction you would be blowing on it. You might have to grind/file a screwdriver to fit down in to remove the jet. Then don't loose the gasket behind the jet.

old · Sep 13, 2014

Blowing out that jet does very little if it has some dirt or rust clogging it. You need to spray or out with car cleaner spray and then use a piece of wire or as I use a torch tip cleaner tool and poke it out some then more carb cleaner

2underage · Sep 14, 2014

Stop using ether as you can undo all of your hard work. You have a fuel problem..either the fuel line is plugged or the float valve is not dropping to let fuel into the carb. You stated it is a new carb and that means you will not need to clean it just yet but sometimes a new carb will have the float needle stick because some of the cleaner has become sticky [I have had this problem] and the needle valve wont release and let the fuel in. To cure, take the carb apart and remove the needle valve and then clean it. I have tried carb cleaner and other solvents but I had the most success by putting the needle it a pan of boiling water for a few minutes.
I would make sure I had a full flow of fuel going into the carb.

Mark - IN. · Sep 15, 2014

A shot of ether down the carb and it keeps running, is a fuel problem. That's how I just narrowed mine down to the carb, but I didn't purchase a new or rebuilt one. Since mine was running until last weekend...same exact problem as yours, died, starts and runs for a couple of seconds and died. I took mine off, took the mixture screw out and a plug that looks like covered a jet, and dunked and swished, and flipped, drained, and over and over again in carb/parts cleaner for about a half hour until decades of crap and tarnish quit coming out, and then I did the same a few times in gasoline to flush the cleaner and any fine silt out. Mine is working now, and my B is running. Whatever clogged the jet or a passage appears to have been cleaned out.

Good luck. If you have good fuel flow up to your carb, and ether down the throat will keep it running, you have a carb issue.

Mark

allis chalmers B initial startup problem

rosedale123

Member

steve(ill)

Well-known Member

cole in mo.

Well-known Member

tractorguy2

Well-known Member

Dick L

Well-known Member

old

Well-known Member

2underage

Well-known Member

Mark - IN.

Well-known Member

Similar threads