Stalling on a incline

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CoombsCars
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Stalling on a incline

Post by CoombsCars » Tue Aug 12, 2025 5:08 pm

Does anyone have experience with what the rate of incline may be in order to starve the carburetor and cause my T to stall? Also can this be helped or abated with high gear and / or timing or throttle changes. Lastly, I replaced my Holley NH with a completely rebuilt (new) carb but for the life of me I cannot get it to stop leaking out of the overflow port. I've twice now adjusted the float to no avail.

Thanks
Bobby


speedytinc
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Re: Stalling on a incline

Post by speedytinc » Tue Aug 12, 2025 5:56 pm

1) Maybe you heard the saying "thats a 10 gallon hill" Depends on the amount of fuel in the tank & tank location. An improved T with a cowl tank doesn't have this problem. Some pressurize the tank. Some add a fuel pump. Some carry extra gas to top off.

2) Retarding the spark is important. If you are running on mag, retard to the next node. Retarding a little can put you between nodes & run poorly.
If on battery, you have infinite adjustment. Retard untill the motor runs best. You may get to the point to need low pedal.
This assumes you have a decent motor still putting out 20 HP, Well tuned coils, & a timer that is working well.

2B) @ maximum fuel demand You may be starving for fuel from an undersized needle/seat unit. A hi flow unit will help & many times solves the problem. Such a part is available from Scott Conger.

3) The needle is not seating completely in your "new" carb regardless of your changing the float height.
Get a copy of the T1 service manual & read it regarding carburetor repair & most any T topic. If your carb wont pass the suck test it will leak from over filling.
By overflow port (not a thing) do you mean the air intake hole under the tag? Or the bowl breather next to the choke shaft?


Scott_Conger
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Re: Stalling on a incline

Post by Scott_Conger » Tue Aug 12, 2025 7:16 pm

Scott Conger

Tyranny under the guise of law is still Tyranny

NH Full Flow Float Valves™
Obsolete carburetor parts manufactured


Dan Hatch
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Re: Stalling on a incline

Post by Dan Hatch » Tue Aug 12, 2025 7:26 pm

Number 1 do as Scott says. Best thing for a T next to a NEW radiator.
Number 2: Any trash in tank? Be sure the screen in the potato is clean and working.


John kuehn
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Re: Stalling on a incline

Post by John kuehn » Tue Aug 12, 2025 9:07 pm

Starving for fuel and low on fuel sounds like. T’s don’t have fuel pumps and depend on gravity flow and anything to deprive them of good fuel flow isn’t good.


Norman Kling
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Re: Stalling on a incline

Post by Norman Kling » Tue Aug 12, 2025 9:32 pm

A number of years ago there were carburetor input float valves called Gros Jet. I had one on a 22 and it used to stall going up hills. I replaced with a full flow needle valve and no more problems. Also need clean sediment bulb and screen. Fuel filters other than the sediment bulb are a no no. They just restrict the line.
Norm

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RajoRacer
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Re: Stalling on a incline

Post by RajoRacer » Tue Aug 12, 2025 10:02 pm

"Lastly, I replaced my Holley NH with a completely rebuilt (new) carb" - rebuilt by whom ? Not all "rebuilds" are equal. Apparently, it wasn't bench tested OR something got jarred around during shipment ? Norm has a valid point - if it's a Gross jet, you might consider what John K. stated - reach out to Scott C.

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Steve Jelf
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Re: Stalling on a incline

Post by Steve Jelf » Tue Aug 12, 2025 11:24 pm

I don't remember if this comparison came from Scott, but it shows the ineffective .100" float valve opening that causes fuel starvation, beside the proper .125" opening that doesn't.

NH Valve Openings.jpg
The inevitable often happens.
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1923 Touring


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Re: Stalling on a incline

Post by KBurket » Wed Aug 13, 2025 12:21 am

Here is an old post discussing grose jet valves with photos.
http://www.mtfca.com/discus/messages/411944/469501.html
I had one in one of my Holley carbs and it wouldn’t shut off.


Topic author
CoombsCars
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Re: Stalling on a incline

Post by CoombsCars » Fri Aug 15, 2025 10:12 am

Thanks all. The "new" carb came from Lang's and yes the bowl breather is where it freely flows out. The "potato" is new and clean the tank is questionable. I'm going to pull the tank this weekend; clean it and likely use a tank sealer. Has anyone had experience with tank sealers?

As for the incline, once the tank is clean, I'll completely fill it and try the hill again. The little truck runs GRATE on a flat surface but it really struggles on the hill in my driveway. Via the engine ID numbers I have found it to be a 1920 - its been in the family for years and wasn't run at all for the better part of 30 years. I can't tell if its ever been rebuilt or as manufactured by Ford because most every bolt and screw shows no signs of tool marks. I have no means to ID earlier history other than my wife telling me she used to rice in it with her dad about 40 years ago. I did some basics such a all new wiring harnesses, plugs, fluids, commutator clean inspected, new intake (old one was warped and didn't seal) carb. It starts very easily on battery, idles and has smooth transition through different advance / retard and throttle.

It seems to run better on battery but also runs okay on Mag. The idle increases dramatically when switched to Mag and after a few moments becomes pretty erratic and constantly chasing the spark advance a throttle. Eventually it seems it is just so confused (probably by all my rapid changes) that it just stops. A friend with an A Model said that once started to completely advance the timing but that just seems "foreign" to me.

I'm having a great time working on it and have learned a lot thanks to you folks! But, I really, really cant wait to take it for a true road test.

Thanks again!


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Re: Stalling on a incline

Post by TXGOAT2 » Fri Aug 15, 2025 11:42 am

You need to check your timer. It is probably worn or dirty or needs lubricated with a light oil, if it is a Ford type timer. I suspect that dirt or gum in your fuel system is causing your carburetor issues. There are several things that can cause the problems you're having, and all can be usually be remedied without spending a lot of money or time. I wouldn't coat the gas tank unless it has a lot of rusty surface inside or it leaks. The tank may have debris other than rust in it, also, especially if the vehicle has been sitting for a while.

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