21" Recycler Pro Revs up and down till dying

[aggiejet]

Greetings,

I have a 1994 21" Recycler II Super Pro, model 20438 with a GTS 150 engine. Numbers stamped into valve cover are as follows: 97772 0110 02 92121604 For starters, who made this engine? I guess toro made the engine, but I didn't think Toro actually made engines.

The engine starts and runs and after a brief period of time, will rev up and down or surges until finally dying. If I hold the governor arm or throttle manually open with my finger, the engine will run continuously. Thoughts?

Thanks,
Mark

 

[ILENGINE]

It is a Briggs 3.5 HP engine. May be a bad diaprhagm between the carb and the tank.

 

[aggiejet]

I entered those numbers off of the valve cover into the Briggs and Stratton search on their website and they didn't correspond to any engines Briggs built. That was what threw me off of the Briggs trail.

I put a carb kit as well as dipped in it Chem Tool. I don't remember any specific diaphrams in there, but I'll go look again.

 

[Rivets]

It is a Briggs engines. Your problems one of two things. Bad fuel or dirty carb or both. You're going to have to take the carb apart again and give it a good cleaning. Get a can of carb cleaner and make sure you clean every hole and jet. Remove the mixture screw on the side of the carb and get that jet really good. That is your idle fuel mixing screw. When you put it back in lightly seat it and back it out 1 & 1/4 turns. This is a good starting point. Also check the float level. Turn the carb upside down. The float should be level. Reassemble and try again. You may have to adjust the idle mixing screw to get it to run steady at low speeds. Old gas or water in the gas will give you the same problems. One question. Does the bolt on the bottom of the carb have a hole in it? If it does this must also be cleaned really well.

 

[pugaltitude]

I entered those numbers off of the valve cover into the Briggs and Stratton search on their website and they didn't correspond to any engines Briggs built. That was what threw me off of the Briggs trail.

I put a carb kit as well as dipped in it Chem Tool. I don't remember any specific diaphrams in there, but I'll go look again.

Put a zero in front of the number nine.

 

[ILENGINE]

I was going to suggest that also. New parts lookup system detail that most people don't know.

 

[aggiejet]

It is a Briggs engines. Your problems one of two things. Bad fuel or dirty carb or both. You're going to have to take the carb apart again and give it a good cleaning. Get a can of carb cleaner and make sure you clean every hole and jet. Remove the mixture screw on the side of the carb and get that jet really good. That is your idle fuel mixing screw. When you put it back in lightly seat it and back it out 1 & 1/4 turns. This is a good starting point. Also check the float level. Turn the carb upside down. The float should be level. Reassemble and try again. You may have to adjust the idle mixing screw to get it to run steady at low speeds. Old gas or water in the gas will give you the same problems. One question. Does the bolt on the bottom of the carb have a hole in it? If it does this must also be cleaned really well.

I have done all of those things you described above last fall. I completely disassembled the carb and gave it a Chem Tool dip and put a carb kit in it. The carb did have a lot of varnish in it from old gas that had been left in there for a couple of years. (I had given the mower to my mom, as I moved to a bigger yard and no longer needed the Recycler. It didn't get winterized at her house. I am trying to fix the mower so my son can mow lawns with it this summer) After putting everything back together, I could never get the surging to stop regardless of how much tweaking I did to the carb. I finally gave up in frustration and thought the problem must be governor related, and decided to wait until now to tackle it. But before I start splitting the case to replace the governor, I decided it would be prudent to absolutely eliminate carbureation(sp) issues first. Based on things I am reading in this forum and just random google searches, the surging is a carburetor problem. I will go take the carb apart again and check the the holes in the bottom screw/jet. I don't think I replaced the Welsh plug last fall. Does that make any difference?

As an additional clue, the mower runs at slow idle (turtle setting) forever. It is only at fast speed (rabbit) that the surging starts. And, it is intermittent. This is what is driving me nuts. Sometimes the mower will run for several minutes without surging. What is constant is that every time I try to engage the blade, the engine dies. (Which makes it look like a governor problem to me) But if I hold the throttle plate open while I engage the blade, it will run just fine for a while, before it starts surging at some point again.

Thanks for the input to the model number. I found a pretty good engine manual on the Toro website, which includes theory of operation information, which I like. Out of curiosity, I would like to see a clear picture of the governor, so I could understand that thing a little better. According to Toro's website, this is a 5.5 horse engine. I found the engine on the B/S website as well.

Thanks,
Mark

 

[Rivets]

Mark, it is NOT the governor!!!! Believe me I have seen this a hundred times. If there is no hole in the screw jet and you have done the best job you can cleaning the carb, it is time to replace it. You could also run a wire up through the main nozzle. If there is a hole in the center of the screw/ jet, make sure you find a very, very small hole in the side and clean it. It will look like a piece of dirt, just above the threads.

 

[aggiejet]

All,

Problem solved, and with a bit of egg on my face. This afternoon I removed the fuel line to take off the carburetor in order to clean it again. When I loosened the fuel line, fuel came out and it was ORANGE looking. I knew immediately that the tank was contaminated. I had not thought to clean the tank out last fall. So I did that and cleaned the carburetor again. Mower now starts on first pull and runs with no surging. Amazing after 19 years and quite of bit of use, and then several years of sitting.

As an interesting/perplexing/frustrating side note, after the the first reinstall today after the tank cleaning, the engine started, ran briefly and then died. After several pulls and no start I decided something was wrong. I removed the nut that holds the bowl on and no fuel ran out. I removed the bowl and discovered the bowl was empty and that the float would not allow any fuel into the bowl. My carburetor is the style with a main jet that screws into the bottom of the carburetor body(into which the carburetor plug screws into that holds the bowl in place ) A round thin metal disc called a float limiter is assembled underneath the float and held in place by the main jet.http://bsintek.basco.com/BriggsDocumentDisplay/Z6hltEVJ1DajI.pdf There's the link if your still interested at this point. Anyhow, I thought the float needle seat was dislodged and of course damaged it trying to poke it further into the carb housing. So off to the local small engine shop, where for a mere 8.50 I got a new needle and seat. I put the new seat in, gave it a test and everything worked fine. Assembled carb back and installed it on mower, and on first pull, she started and ran.:thumbsup:

Thanks for your help.

Mark

 

[aggiejet]

I tried to post a pretty detailed rant of my day's thrashing about and buffoonery trying to fix my engine, but it disappeared into the cyber oblivion.

That said, I got the engine running. I had a contaminated gas tank, and it was ruining the the fresh gas I was using. After I cleaned the tank, ( I used Sea Foam) the engine started on the first pull. Amazing after 19 years.

One thing I learned today while at the parts store getting a new needle and seat, was that there are some inlet holes in the throat of the carburetor that can become clogged. They are in line with the Welch plug and can be cleaned with a cutting torch tip cleaner brush.

Thanks to everyone for their help.
Mark