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Discussion Starter #1 (Edited by Moderator)
Ariens 7524 with Tecumseh oh195 engine
The Tecumseh motor on my Ariens started surging last year so I rebuilt the carb. it now runs great but was leaking gas our of the drain on the float bowl. (series 1 emission carb). I bought a new bowl without a drain plug and installed it. The carb was leaking just enough gas to make my garage smell like gas. I installed a new o-ring between the float bowl and carb and it got worse. This is what I have tried to stop leak.
1.removed drain from original bowl and plugged it with screw head and jb weld. reinstalled it.
2. adjusted float to 11/64 and made sure needle clip was pointing correct way.
3. checked float in sink to make sure it wasn't leaking.
4. replaced needle, seat, gaskets, making sure seat had groove toward carb body. adjusted the float to 7/32
the carb still leaks around the gasket between carb and float bowl. and gas goes up primer tube.
I have searched and can't find anything else to try so I would appreciate any help from an expert
 

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If the carb is overflowing and leaking, there has to be a problem with the float level setting, or the needle valve not seating properly when the float is all the way up. You said you confirmed that the float is not leaking and full of gas. Removing the drain screw won't solve the problem. The leaking O ring indicates there may be damage to the ring or junk somewhere around the sealing surfaces, however, that still doesn't solve the problem of the needle valve not sealing properly and allowing fuel to continually flow into the bowl.

When the float rises up with gas in the bowl, it lifts the needle valve into the fuel orifice to seal it off. If it doesn't seal, gas keeps coming into the bowl and it will drip, and possibly flow up the main jet, into the intake port and leak through the intake valve, and end up in the crankcase.

Check the oil level and see if its too high, and the oil smells like gas. If so, change the oil.

You did not mention if you have a fuel shutoff valve on your engine. If not, install one which will take care of the problem until you have time to recheck the carb.
 

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If you have gas going up or leaking out the primer nipple with the line off you definitely have a float or needle/seat issue. Even though they are new they might be bad or the wrong parts for the carb or not properly installed.

Might not be the bowl gasket leaking but gas leaking down onto it.
 

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i doubt the gaskets are bad. did you clean up the surface where the gasket meets the carb body? its often corroded
 

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^^ exactly..... fought that to many time to count. You may have to sand/grind it smooth. That's why I often encourage people to just cough up the $20 for the China carb on ebay delivered ready to go. Have not had any trouble with those.....
 

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Agree with

bad69cat

I only paid 12 for my ebay china carb. A Techumseh branded gasket set for the carb was 6 at my local shop. Then I needed a new float as well, mine was sinking. I was so disgusted with it I got 2 china carbs in case one did not work. It worked fine though and the motor runs better than it has in years even with my past carb cleanings.

I might start taking the carb off the blower for the summer, spray inside it with WD40 and keep the carb in the house.

The new carb is adjustable and has a bowl drain as well.
 

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^^ exactly..... fought that to many time to count. You may have to sand/grind it smooth. That's why I often encourage people to just cough up the $20 for the China carb on ebay delivered ready to go. Have not had any trouble with those.....

+1 here on the repops. Not Made in USA, but a Cost Effective Solution. To Me, Coughing up a few bucks for a guaranteed solution is a no-brainer.
 

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^^ exactly..... fought that to many time to count. You may have to sand/grind it smooth. That's why I often encourage people to just cough up the $20 for the China carb on ebay delivered ready to go. Have not had any trouble with those.....
Agreed. I fought with a carb on a 6 hp Tecumseh on an old tiller that just would not work well. I bought the Chinese carb and had to do a bit of modding to adapt it to my tiller controls (choke handle needed to be reversed - should not be an issue on a snowblower). The motor fired up on the first pull of the starter rope and has run well ever since. That relief of frustration is easily worth the $20 IMO.
 

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If the bowl gasket is the problem, wipe it down with a little transmission fluid and it will swell into place. As WheelHorseBoy says, there is a tiny breather hole that if it plugs up, your carb will get airbound and push fuel up and out of the jet.
 

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I had this problem and tried to figure it out for some time. The gaskt between the bowl and carburetor is large or more round on one side compared with the other. The smaller side matches to the carburetor with the bowl. You will note that the lip of the bowl is more round than the lip of the carburetor and the larger side of the ring fills it in.
 

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I had a similar problem last year on a 5 horse tec. Couldn’t get it sealed after doing all of the above. Wasn’t the first time with this machine. But it was the last. The motor now sits in the back of garage. HF Predator. One pull starting. Much quieter and more powerful. I have more of a problem remembering to turn the on switch on :).
Wish you the best of luck
 

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I find when this happens, the needle isn't seated into the body of the carb. Somehow the float dropped too low, and the needle fell out. Or a bad gasket as addressed.
 

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Hello. I have the same problem. I have an older Snapper mower with the VM80 Tecumseh. It uses a throttle. I have installed 2 seats and it still leaks at the rim of the bowl gasket. But the confusing part is the engine will crank but has no rpms. And if I try to increase the rpms, the engine will 'pop', like a back fire and go dead. Will this carb gas leak cause the strange poor running of the engine? And also, what should I check to fix this gas leak. Try another seat? This is a riding Snapper mower, by the way.
 

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A couple of thoughts on this old thread and to answer your question clockman.

First, I have been super frustrated with leaking carbs too. Often times I will just attempt to clean a dirty carb which is NOT leaking and by golly, after cleaning the carb will leak. Ticks me off.

Anyhow - there are a lot of comments here blaming the float bowl gasket. Seems many here felt this was the culprit.
However, unless I am mistaken, a perfect carb on a machine sitting in your garage on a level surface will only fill the bowl to a level BELOW the top of the float bowl. If the float is properly set, the fuel should shut off before the gas would rise to the gasket - right? In my mind the gasket is to stop gas from leaking while the device is moved around and the fuel is sloshing around the bowl.

I'll admit it's frustrating to see so many jump on the gasket bandwagon since it's only a symptom of something else. Sure, a new gasket, ATF on the gasket, buying OEM gaskets all sound like good advice but it will not fix the issue. Even if you got the perfect gasket to seal it will not resolve the bigger issue of gas being so darn high in the bowl. Agree?

I have concluded the main reason for these leaky carbs is one of three things:
1. Needle seat is not working as intended
2. Needle is not working as intended
3. Float has slow leak or is not properly set.

Clockman - I would say you still need to work on the needle and seat. The gas is flooding the engine and not allowing it to run properly. I would consider adding a fuel cutoff switch and let the float bowl fill for a bit then turn off the fuel switch. It should fix your issue and let you know your carb has a fuel level that is too high and it's spilling into the cylinder. Good luck!
 

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I keep a few Chinese carbs in stock all the time....when I get down to only one or two, I order more. I have a five gallon bucket of old carbs that I may take tghe time to clean if I get REALLY bored.
 

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@Waylon, one more to add to your list: A pressurized fuel tank /line/system.
IDK how that would happen on a small engine but it would cause the symptom if it did.
 

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Well, until the bowl overfilled and the needle sealed tighter. With a needle and the small orifice, it should hold back and realistically imaginable pressure. I seem to recall reading somewhere that the float valve should easily hold back several psi.

And, as just stated, fuel level should *NOT* be above the bowl gasket! Sitting still a properly working machine without a bowl gasket will not leak . . .

So, either the float/needle/clip or bowl orientation is wrong, or another possibility is that the bowl has developed pinholes.
 

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Make sure the float level is proper, there should be a measurement from the top of the bowl. Also make sure your float is not leaking or absorbing fuel.
 
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