8N with no power ( update )

[RLBII]

Found a problem today, Small needle under the nozzle in the carb. Took it out and now it runs fine. The FO4 manual shows it in there but a fried who works on carbs didnt know why it was needed. For some reason this would allow you to remove the main adjustment needle from the carb and the tractor would run better without it. Now there is no need to have half choke on and the main adjustment needle actually adjusts the way it runs unlike before. Any thoughts?

 

[Dell (WA)]

RLBII......what small needle in the FO-4 manual??? Better give an illustration and part number. Everything I know about the M/S and the FO-4 is correctly illustrated, identified, and required. ........respectfully, Dell

 

[GB in MT.]

RLBII;
Ditto to all that Dell just told you.
Every part on a Marvel/Schebler TSX carb., was put there for a reason.
I would be interested to know exactly what part your friend told you to do away with.!!!!?????

Gary :shock:

 

[Bill(Wis)]

I don't own an N and never intend to but if it's the needle valve I'm thinking of, you'd better do four things. 1. Run the tractor at full power when you're using it. 2. Shut the thing down with a fuel shutoff valve. 3. Wear track shoes. 4. Carry a fire extinguisher.

 

[Paul in MN]

RLBII,

If your tractor runs best with this needle valve taken out, then that is proof that your carb is full of some kind of crap. It needs to be taken off, thoroughly cleaned (with carb cleaner), rinsed with lacquer thinner, all passages blown out with compressed air, and a new carb kit installed. Somewhere on this site is a good set of instructions for the carb o'haul.

Do not run with that needle valve out, you run the risk of a gasoline fire destroying the tractor and maybe some building it is parked in.

Paul in MN

 

[RLBII]

I am running the tractor with the main adjustment needle in and it works fine now. here is a picture of the ( main jet?? ) that the main adjustment needle seated on. Looks like part number 9N9533. This is what was taken out. After your replies,I took a better look at the manual and I dont see this part where it was found. Thanks for your concern also.

 

[JMOR]

(quoted from post at 16:52:57 01/21/09) I am running the tractor with the main adjustment needle in and it works fine now. here is a picture of the ( main jet?? ) that the main adjustment needle seated on. Looks like part number 9N9533. This is what was taken out. After your replies,I took a better look at the manual and I dont see this part where it was found. Thanks for your concern also.

Your terminology in post where you mentioned "small needle under the nozzle" is what got everyone questioning things. What you picture is in fact the Main Jet & the PN is correct for that. The reason it works without it is that it is in series with the Main Power Adjust Needle, as far as gasoline flow is concerned, so you just set the flow with the Main Power Adjust Needle and all is well. The Main Jet that you have removed simply set an upper flow limit anyway & virtually always, you operate below that as set by Main Power Adjust needle. My 'guess' is that your jet PN 9N 9533 has too small an orifice........the after market replacement jets are notorious for being a variety of incorrect sizes.

 

[Dell (WA)]

RLBII......this is what you wrote......"Found a problem today, Small needle under the nozzle in the carb. Took it out and now it runs fine".......and now you show the mainjet p/n: 9N9533 as the "problem"; which is NOT a NEEDLE its a JET.......sheeesh!!!

The mainjet is at the bottom of the slanted emulsion tube p/n: 9N9530 which must be removed for access to mainjet. It should be intuitively obvious, you can NOT have 2-mainjets in the same place. So yes, iff'n yer carburetor buddy dumped out an extra jet, yer down-pointing mainjet adjuster wouldn't adjust. And you STILL have the real mainjet inplace 'cuz it now adjusts.

Congratulations on yer inarticulate miss-leading descriptions......respectfully, Dell