History and Background:
30-40 year old Simplicity snow blower with 6 hp B&S, and up-draft carb. (Mod: 146412, Typ: 1159-1, Code: 6907181)
In the past, this has always been a good runner and starter. On start, full choke for no more than 3 revolutions (i.e. about 1 second) and then full-off with choke, and the engine jumps to normal speed.
Last year, it required partial choke after running in order to keep it running (i.e. starved for fuel).
Two weeks ago I started it for the first time this year. It needed 95% choke to run and had no power (obvious fuel blockage). Here’s the odd part; I put it away until I had more time to pull the carb and when I pulled it out, I found that all of the fuel had drained out of it. (there is no drain on the bowl).
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Yesterday I found the primary problem was a piece of debris in the high-speed jet. I cleaned the carb and put it all back together. I set the high speed adjustment to 1-1/2 turns as a starting point. After several pulls and a couple of firings, I noticed raw fuel leaking out of the air inlet (Re: up-draft carb). The only way I could get it to start was to fully close the high-speed adjustment, but this required 1/2 choke to run. After a while, I was able to back out the high-speed about 1 to 1-1/2 turns and it seemed to run very well (also no choke).

This morning when I went to use it, it would only fire if I had full-off on the choke, and I noticed raw fuel running out of the air intake. I finally got it to partially run where it would sustain firing, but fire at only about 2-3 times per second. Thinking that it was just burning off all of the excess raw fuel, I let it chug along like this for about a minute. When it did not change, I finally reached in and began turning the high-speed adjustment in until it was fully closed. The engine roared to life and seemed to run well.

After one or two passes down the driveway, it began to bog down, so I backed out the high-speed adjustment slightly. After a little while, I had to back it out some more. Then again a little while after that. Right now I think it is back to between 1 and 1-1/2 turns.

So what could be wrong with this that it floods out when cold, but then starves when hot? By the way, the low-speed adjustment has little impact except for the extremes.

P.S. This carb is end-of-life, so there is no kit available.

I would say that the seat may be your problem, and or possibly the float. You can still get an after market kit for your carburetor.

http://tewarehouse.com/7-02010

Tulsa engine warehouse lists it for $10.99

will that work for him even though the kit says 7-9hp?

will that work for him even though the kit says 7-9hp?


Yes, The above kit is listed for his engine as well per Briggs.

Ok, I found a parts list at Briggs that covers models 146400 to 146468, so this should include my model, and within this list it does have the same kit number for the carb.

However, I am still curious to know the reasons. BTW, this has a brass doughnut float, which is not included in the kit, but don’t imagine it would be needed.

I used it again yesterday with better success, but that was simply because I knew what to expect. To start it, I left the choke open and closed the high speed adjustment. After 20-30 seconds, I began to slowly open the high speed, and then after a minute or two of running under load, I opened it a little further.

What doesn’t make sense is that the engine should want more fuel (or less air) when it is cold and less when it is hot, so what is making it respond opposite? Is there an air adjustment that could be out of whack, or some port that is fouled?

Oh, by the way I am also curious about the governor spring. I apologize. I know I can find this with a search, but is the spring too loose or too tight if the engine speed constantly oscillates? It has been doing this since I was a kid (35 years) so I always assumed it was normal.

sounds like you need to retorqe the head bolts or replace a gasket, it's lean cold because it's sucking air, but once warm the metal expands & seals the gasket, running rich.

hth, --Lucky

the engine speed constantly oscillates? It has been doing this since I was a kid (35 years) so I always assumed it was normal.


From the sound of the above statement this carb has been running a little lean for the past 35yrs (not adjusted properly from day one).

It also sounds like you have two problems;

1) Worn throttle shaft/carb body after running this long "hunting", If so it could be sucking air.

2) Worn leaking float needle valve/seat or a pin hole in the float (fuel inside) causing it to flood.

Check the throttle shaft for wear, If it is still tight get the rebuild kit and install it with the new float valve seat. Then test run/adjust as necessary.

So I ordered a rebuild kit from Tulsa Engine Warehouse and I was impressed with how fast it arrived. So today I decided to pull the carb apart and get it rebuilt. I opened the bag of parts and couldn’t find the high speed jet..............at first.

It was a used/returned kit and it turns out some jacka$$ bought this kit, used the parts that he needed, and then returned his used parts in the bag to Tulsa Engine. The high speed jet was cut in half and hacked apart because he didn’t know how to remove it. The float valve seat was drilled out to remove it, and he also put this into the bag.

I could understand an honest mistake of returning something and forgetting to put a piece back in the bag, but this guy deliberately returned his used parts!!!!

That happened only once where I work with a chain saw carb kit. Now store policy is, You open you own.....

So I ordered a rebuild kit from Tulsa Engine Warehouse and I was impressed with how fast it arrived. So today I decided to pull the carb apart and get it rebuilt. I opened the bag of parts and couldn’t find the high speed jet..............at first.

It was a used/returned kit and it turns out some jacka$$ bought this kit, used the parts that he needed, and then returned his used parts in the bag to Tulsa Engine. The high speed jet was cut in half and hacked apart because he didn’t know how to remove it. The float valve seat was drilled out to remove it, and he also put this into the bag.

I could understand an honest mistake of returning something and forgetting to put a piece back in the bag, but this guy deliberately returned his used parts!!!!


Let us know later on Wednesday what TEW says when you call them. This can be part of the problem with ordering parts online, when you have to go through this situation, it's alot less likely to be believed than if you were in the store in person.

I called Tulsa Engine this morning and spoke with a nice sales rep, Darren. He too was a bit shocked at what I told him and indicated that a new kit would be sent out. I called him back this afternoon just to verify. He also stated that he flagged the order to verify that all parts were in the kit before shipping, so that really makes me feel much better.

I want to add that at no time was I considering this to be a fault of Tulsa Engine. Someone deliberately tried to cheat them, and I was the final victim. Tulsa handled this quite well without hesitation.

I volunteered to send a couple of pictures of the parts to Darren. Here is a picture of the used parts. Sorry if they are large, but I wanted to make sure they could see the details.

You can see in the second picture that the idiot cut into the high-speed jet in several places because he could not get the bowl off with the jet still installed. He didn't realize that he needed to unscrew the jet before removing the bowl (I know, because I made the same mistake too, but I was not dumb enough to cut the jet in the process.) You can also see that he drilled out the float valve seat.

http://www.waterfront-woods.com/tempgraphics/FullKit.jpg

http://www.waterfront-woods.com/tempgraphics/JetClose.jpg

Goober must have worked on that jet.... :rolleyes:

Glad to hear they took care of it for you.