carb jet hole

[vit16]

Guys, does anyone knows the diameter or the number for the original high speed jet?
As you may remember my engine is rated 113 hp and the previous owner installed another carb for my engine. I am suspecting that this carb does not supplyes enough fuel.
I carburated it perfectly and works perfectly good but at high load Imean just in 4th in flat terrain it won't go more than 30 mph.
I suspect this jet is smaller than it has to be.
I did CFM calculations and seems to be smaller than it should.
That is why I wanted to compare the hi jet from what you have.

I did some searches and ther was a guy in another forum that installed an alternative carb and did well. but it was also bigger than my Holley carb.
any suggestions from you is always highly appreciated

Ron

[vit16]

I will be trying different solutions and will let you know

[NAM VET]

I have no idea what the inside of the stock ET carbs are like, all I know is that after a CT rebuild, mine is defector. Carbs have always been a mystery to me. Hal

[vit16]

yes hahaha

I still have to buy those little parts to try.
Wont be much help for those guys with stock carb but my idea is to make it work correctly.
I sill have to test compression just in case.

[Kaegi]

should go much faster than 30 with stock engine and carb. 55 all day. it will go faster but then it gets hard on engine

[sturmtyger380]

Do you still have the governor mounted for this carburetor? The governor will force the engine to have less power and if not adjusted correctly will cause issues like this.

[vit16]

Hello Guys! thanks for the replies!
What is the governor looks like?
I just see a lever inside the exhaust manifold. But nothing between the carb and intake manifold. The throttle pedal links directly to the carb with no other system if that helps

I still have to check some other things like vacuum looses in the wipers, power valve in the carb, air filter size to be enough, ignition advance at high RPM if it works or not.
Engine works fine with no hesitaton, no missfires, no smoke, just that "limitation"

[sturmtyger380]

The governor sits right under the carburetor and decides on its own how much power to allow the stomp happy GI to give to the engine.

Here is a link to what it looks like:

https://store.midwestmilitary.com/product-p/7001067.htm

Here is an old post on how to adjust it:

http://www.g741.org/PHPBB/viewtopic.php?f=3&t=7886

[vit16]

Ahh ok no, I don't have that. It was removed by the previous owner.
I still have something inside the exhaust manifold like a valve that is loosen. there are no parts in my engine that links intake with exhaust like in this picture

[NAM VET]

if still per military build, and not since removed, there is a flap just under the carb, with a brass nut on a similar shaft, part V in the diagram posted, which allows the flap to allow hot exhaust to heat the incoming carb air, for really cold (Alaska) operating temps. On my truck, here in UpStatre SC, I keep mine turned so it doesn't heat the incoming air. If the flap on the shaft is absent or broken, it is necessary to separate the intake an exhaust components to have it welded onto the shaft. If you do separate the two, it is often necessary to have the bolted up manifolds machined to be flat to the head.

NV

[vit16]

yes that's What I have! there is a flap there in the exhaust and just gravity moves it!!

[sturmtyger380]

vit16 - Does it stay at or below -4c (25f) where you live during the warmest part of the day in your winter?

If it does not get and stay that cold you need to keep the flap closed year round. With the flap open more heat will go to the carburetor riser and make it hotter than it needs to be to vaporize the fuel. It might could lead to vapor lock. I am guessing you have a different carburetor than the Military one?

Like NamVet says for us guys here in the Southern US it stays closed. I will weld mine closed when I get to that point.

[vit16]

Hello guys!

Yes here in my location it goes from 0°C to 40°C in summer so I will close it as suggested!!

this are the only pics I have now for the manifolds. Also there is like a removable funnel there

[vit16]

Hello Guys!, did some mods yesterday
Replaced carb main jet and now it works better. I could only use 4th gear if 3r was highly reved. Now I can go from 3rd to 4th at any RPM.
The engine feels goog but it still wont go upper than 35 MPH per gauge... that is something to test too.
Still have to measure compression.

At the end of the day I went to a much higher hole but It didn't change anything, seems that the carb reached a limit so I will test another parts too.
I know that you may be thinkng of "why don't you just put the original carb" my reason is that it is difficult to find one here. I will be waiting to but it when travelling back to the US again.

[vit16]

what do you think about that flap?