John Deere 111 Flooding

[bgsengine]

and question is did someone swap the carb or the engine. Carb for his model and type is 491026 and for a mere $1000 he can get a replacement.
http://www.ebay.ca/itm/Carburetor-for-B ... 2555146279
Guess I won't throw out that container of old flojets.
Actually someone just left a 10 hp yard pro at our church metal dumpster. However it was gravity feed.

Heh I see a few possibilities with that listing - A) Carburetor is no longer available so they bought out someplace and now control the market (or think they do) or B) this is a drop-ship seller that does not have any inventory on hand , and the unit is on backorder at their supplier, so they jack up the price to astronomical levels to discourage anyone from buying one, while they are still able to leave the listing active (stealing views and maintaining their ranking on the listing) or C) the seller is on vacation and thats how they "pause" their listing (see previous item B) or any combinatino of all of the above .. Oh yeah D) seller had a typo while entering his price and did not notice. (I did the same once, and had a $20 part listed at $2.097.00 didnt even realize it until someone sent me a message joking about it. )

[KE4AVB]

Ahhh I see they think they got the market cornered like that drug did by raising the price 100 fold or more just because were greedy or the BGS said just don't have them.

[lefty]

I have a pretty decent history on the machine. My friend had it given to him by a neighbor who had it since it was new. It was my neighbor as well but they moved away about 7 years ago. So the machine ran well since then until it sat and wouldn't start. This was maybe 2 years ago. My friend gave it to me and I serviced it including a carb clean. It ran well after that but then sat again and wouldn't start.

My friend definitely didn't change out the carb but we don't know if the original owner maybe had it done at some point.

So the concensus is I have the wrong carb on this machine. But since it ran well for many years, is there a workaround? I was thinking maybe replace the needle and seat with the ones from the kit and adjust the float to put a little more pressure on them?

Just so I understand, what is the difference between having a brass seat vs. rubber? (I forget the proper name so I call it rubber). Does the brass seat with the rubber tipped needle create a better seal able to withstand more fuel pressure?

[lefty]

Follow up question:

Please all humor me as I think out loud....

So applying my own brain and trying to wrap my head around the physics here... I'm guessing that with a fuel pump, no matter what the needle and seat configuration are, the needle and seat serve only to stop fuel flow when the motor is turned off. I'm guessing that the fuel pump, when running, will force the needle open in a pulsating fashion no matter what the configuration.

If I'm right, will bad fuel lead to this problem. In other words, with bad fuel, combustion will be poor resulting in excess fluid build up in the fuel system causing spuddering and stall, as well as the subsequent fluid dump into the intake?

The reason I ask is because I decided to drain the tank. What came out looked ok but smelled nothing like "gas".

I apologize for not checking that first. I know that should be one of the first checks.

[bgsengine]

Follow up question:

Please all humor me as I think out loud....

So applying my own brain and trying to wrap my head around the physics here... I'm guessing that with a fuel pump, no matter what the needle and seat configuration are, the needle and seat serve only to stop fuel flow when the motor is turned off. I'm guessing that the fuel pump, when running, will force the needle open in a pulsating fashion no matter what the configuration.

wrong guess . fuel pump does not (or should not) produce enough pressure (less than 7 PSI or so) to pop the float needle off when the float is under tension from the fuel level in the carb bowl - so, float needle and seat working properly will *SHUT OFF* fuel flow even under fuel pump pressure .

If I'm right, will bad fuel lead to this problem. In other words, with bad fuel, combustion will be poor resulting in excess fluid build up in the fuel system causing spuddering and stall, as well as the subsequent fluid dump into the intake?

not really bad fuel can cause any number of issues and contribute to the issues you have stated However bad fuel will not in and of itself cause your flooding problem - you will see the same issue even with fresh gas as long as that float needle and seat continues to leak - fuel leaking past there will overflow into the carburetor and on that particular carburetor it backs up through the bowl vent and dumps out right under the air cleaner

The reason I ask is because I decided to drain the tank. What came out looked ok but smelled nothing like "gas".

I apologize for not checking that first. I know that should be one of the first checks.

bad gas WILL cause gum and varnish build up in the carburetor which will cause things to get sticky, or jets and holes to be gummed up, but it typically will NOT cause the carburetor to flood (unless the build up is so bad the float needle won't move or is stuck)

[KE4AVB]

Or piece of harden stuff from the fuel supply get lodged the needle seat area. Water in fuel can cause corrosion that can do this also. I just repaired a JD 150 Kohler CV15 where fuel that put in the tank contained water and rust, this along with a bad fuel filter (element not even filtering as it was just floating in it encasement) lead to the carburetor flooding while running as the needle was unable to seal against the seat. After cleaning removing all the rust and water corrosion plus installing a new filter then the carburetor no longer flooded.

This trash problem can be aggravated if someone flips the fuel filter after it contains trash and fill the carb with trash.

[lefty]

Thanks guys. Understood.

I have a fresh filter on this and have cleaned the carb twice, except for the main nozzle, which as I stated in a past post, hasn't been removed due to it being stripped. (i may try to replace it depending on my level of courage) I was wondering if a clog in the nozzle may cause this but think I realize, after BG's post, that the needle should still seat and prevent the flood.

So we're dialed into a needle and seat problem. I have new ones coming in today in a kit. I'll replace them and see if the results are good.

So at this point in me "career", I've cleaned several carbs and replaced parts from kits, both bowl and diaphram types. I've used parts from kits, mostly gaskets, diaphrams and such. But I haven't replaced many needles and seats. Mainly because they never really look like the need replacing. I have done it, but wasn't sure why.

Question: How do you tell visually if a needle and seat bad and need replacing? They always look the same to me. Assuming they are clean, what else causes them to fail?

The opinion that I probably have the wrong carb on this has not been lost on me. But replacing it with the correct carb is not an option for the owner given the high price. So I'd like to try to keep this one going if possible.

[KE4AVB]

Most times you can see the wear; other times it takes a magnifier to see. With rubber tip needles its the rubber that wears. I have seen lots tips with a wear ring in the rubber. A few cases of just one area damage and only visible under magnification. With the all metal needles it usually the seat wears similar to rubber tip needle but they more prone nicks. Now metal seats the fuel itself can actually etch the metal leading to leakage. I even seen one rubber tip where had came partially and was sitting cockeyed.

Some the carburetors I work on here are metal to metal contact seating too which can be a bear to stop leakage but getting away from the float valve version and getting into the power needle systems. Now I have one with the last 6 months where the float valve was metal to metal seating.

When installing a carburetor repair kit and it has the float valve components I always go ahead and replace them to prevent reworks.

I seldom go with GND kits on those 2 cycle carburetors as I find the metering lever and needle worn most times anyway or a missing welch plug where someone else had already been in the carburetor. On the subject of welch plugs I seldom need to remove them as my UC get in there very well when cleaning. I had to replace an $100 Stihl Zama carburetor last year because some idiot removed the welch plug over the main nozzle and they are not available as a separate item and none of my spares were large enough to work down to fit. Just a waste for that was the only problem I found.

[lefty]

might also be a bad float (cracked, corroded, etc)

Bingo. I finally got the opportunity to pull this apart again today and sure enough...the float was loaded. Looks like there's a litte tiny crack in it. Makes a lot of sense now. Feel kind of foolish that I didn't shake the float the first time I pulled it apart. Thanks to everyone...as usual, I learned a bunch.

[KE4AVB]

Learning is slow process but lessons like this will stick with you longer.

Even us pros are still learning new things. Like the Kohler CV I ma working on where the metal line had rust in it. I had cleaned the carburetor that had water and rust in it. Since I had a known bad fuel filter I assumed that was the root cause. Well customer came to get his mower and it was flooding out again. Took apart the carb and found trash and rust again. Re cleaned the carb then it dawn on me that rust was coming from the metal fuel line since there had been water in the fuel system. Put the line in the UC and what came looked like coffee with a little cream in it along with some trash.