Model A carburetor issues (still)

[36hatteras]

OKI have a 1946 model A, John deere and it will crank. And run for about 20 minutes and then the carburetor just floods. Can anybody help me please? I've had the carburetor rebuilt and the mechanics said there was nothing wrong with it.

 

[Loosehandle]

OKI have a 1946 model A, John deere and it will crank. And run for about 20 minutes and then the carburetor just floods. Can anybody help me please? I've had the carburetor rebuilt and the mechanics said there was nothing wrong with it.

Did they install a new float? Also you could try running it with the gas cap loose in case pressure is building up in tank.

 

[Fixingfarmer]

Find a different mechanic or a different carb. Sometimes the 70 year old passages can just plain not seal up if a float seat is put in. I know they are expensive but the first one lasted how long? Although the Float for sure is the first thing to try. Those metal floats don’t last forever take it out and submerge it for a couple hours or better yet overnight. Then take the rock off it and see if it raises to the top. If not it’s full of fuel. I think yours is going to be a one piece horseshoe shape so there’s not 2 separate air chambers

 

[Mark-Ia]

Easiest way to check a float for holes; submerse it in a pan of hot or boiling water. It will release air bubbles showing where the hole is at.

 

[36hatteras]

Find a different mechanic or a different carb. Sometimes the 70 year old passages can just plain not seal up if a float seat is put in. I know they are expensive but the first one lasted how long? Although the Float for sure is the first thing to try. Those metal floats don’t last forever take it out and submerge it for a couple hours or better yet overnight. Then take the rock off it and see if it raises to the top. If not it’s full of fuel. I think yours is going to be a one piece horseshoe shape so there’s not 2 separate air chambers

He did not replace the float because he said it was fine.

 

[36hatteras]

Did they install a new float? Also you could try running it with the gas cap loose in case pressure is building up in tank.

He did not replace the float because he said it was fine. However, I will try with the gas cap off. That does make sense because it does it every time after about 20 minutes.

 

[rwhb12]

It is gas or kero and gas?

Russ

 

[36hatteras]

He did not replace the float because he said it was fine. However, I will try with the gas cap off. That does make sense because it does it every time after about 20 minutes.

I would think if it was the float that it would do it pretty quick but it's usually right out about 20 minutes and then it just floods out starts dripping fuel from the carburetor and then I have to let it sit pull the plugs, clean the plugs and start over and it. Is a hand crank, so you can imagine I'm building muscles.

 

[36hatteras]

It is gas or kero and gas?

Russ

Has been converted to gas only.

 

[rwhb12]

Has been converted to gas only.

It could be that the spark plugs are wrong? I read that the kero plugs run much hotter?

Russ

 

[ffmike790]

Not saying the mechanics didn't know what they were doing, but for peace of mind you might want to double check the float yourself since it was not replaced. If good, then the needle and seat are the next place gas would keep flowing to flood it. I've had current ethanol gas do this to a carburetor just under a year after I replaced parts in it due to flooding when parked and filling the crankcase past full. Although this was not on a tractor engine, the physics/problems are the same. I switched to ethanol free and installed a shutoff valve inline since then. I understand it is when you are running it, but if one of those parts is leaking, it would eventually flood it when running.

The gas cap is a vented type. If you open it and find/hear pressure coming out you want to replace it.

 

[NoDakInMN]

I dunno, but if my carb was pouring out gas, I don't think I would be still believing the mechanic's advice that the float is fine.

 

[Fixingfarmer]

It could be that the spark plugs are wrong? I read that the kero plugs run much hotter?

Russ

I don’t think that would cause flooding however that’s a good topic to bring up since there are 11 choices in the manual for plugs a lot of which are obsolete. What plug to use auto lite? The hotter plugs started on gasoline obviously so how much difference is there?

 

[J.Wondergem]

If the float IS fine, it's sure hanging up on something.

 

[Mike(NEOhio)]

I rebuilt my A carb and found that working around the center tower makes it tricky to get the float level and the proper height. It may be hanging up or contacting somewhere. Take the bowl off and have a look.

 

[Pete in MD]

The gas cap is a vented type. If you open it and find/hear pressure coming out you want to replace it.

If the vent in the gas cap is not working a vacuum will build up in the gas tank and keep gas from flowing to the carb.

 

[NoDakInMN]

I think we have a different definition of what we consider "fine". I would not consider a float malfunctioning in any way to be "fine". This would encompass the float, needle and seat assembly. You can rig up a sight glass to monitor your fuel level in the bowl by removing the bowl drain and installing a brass pipe thread by barb fitting with clear plastic hose attached and routed so it goes up and higher than the bowl, but I think this would just confirm what we already know, that the float, needle and seat is malfunctioning. Things to check are, worn float hinge and pin, obstruction preventing needle from seating, if the needle is all metal, look for worn or gouged tip or seat, or if the needle has a neoprene tip, chuck it and get a metal one, they have a nasty habit of sticking and causing a lack of fuel or an excess of fuel. I fought that battle on a 1964 110, carb would either flood or starve. Every kit had a needle with a neoprene tip and I was replacing them at least every year, finally got an all metal one and it hasn't been a problem for 20 years.

 

[620 John]

I ran across an older thread on an overfueling issue not related to float/needle when I was rebuilding my DLTX 18 carb. In this case it was the bowl vent being plugged. Here's the link:

DLTX carb overflow....NOT needle / seat/float..check this !

DLTX 67 carb on JD late "B". Complete rebuild inc new float, steel needle / seat. Float level set on bench first with fluid and sealed perfectly. Mounted loose on test tractor, turn fuel on fills up and runs full stream out front of carb. (this is why I mount loose first) After hour of...

forums.yesterdaystractors.com

 

[Mike(NEOhio)]

I ran across an older thread on an overfueling issue not related to float/needle when I was rebuilding my DLTX 18 carb. In this case it was the bowl vent being plugged. Here's the link:

DLTX carb overflow....NOT needle / seat/float..check this !

DLTX 67 carb on JD late "B". Complete rebuild inc new float, steel needle / seat. Float level set on bench first with fluid and sealed perfectly. Mounted loose on test tractor, turn fuel on fills up and runs full stream out front of carb. (this is why I mount loose first) After hour of...

forums.yesterdaystractors.com

I just read this. I thought of RandyB yesterday then realized I haven't seen a post from him for a long time. I corresponded with him a few years ago and he gave me good advice on DLTX rebuilds and his adjustment procedure. Anybody know of his current status?

 

[620 John]

I just read this. I thought of RandyB yesterday then realized I haven't seen a post from him for a long time. I corresponded with him a few years ago and he gave me good advice on DLTX rebuilds and his adjustment procedure. Anybody know of his current status?

Don't know of his status but I will say there's a lot of folks who used to post on the JD forum that haven't been around for the last 3-4 years. I can think of at least 5 of them off the top of my head. Hopefully they're doing okay