Tecumseh Carb Bowl Nut

Reply

  #1  
Old 04-19-09, 12:36 AM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Tecumseh Carb Bowl Nut

MODEL: LEV 120
SPEC: 3615608
STAMPED INTO CARB: 5272 E2C

My lawn mower will not start. I removed the carb Bowl Nut and discovered the remains of either a rubber or plastic O-ring inside the center bore of the bowl nut. The Technician's Handbook makes no mention of a part like this.

However, online I found the following comment in a "How To Clean a Tecumseh Carb" page:

"One other thing to watch out for on these carbs is a rubber o-ring sandwiched up at the top of the main jet holder. These can go bad and close up. I found one with a tiny plastic sleeve in the o-ring to keep it open. When I assembled it with a new o-ring and omitted the plastic sleeve, and found it would not start."

The model number for the carb mentioned is similar to the one I have, so it seems reasonable that this is my problem.

After a long online search for Tecumseh Carb parts, I can't even find something similar to the Bowl Nut let alone the O-ring! How do I find a Part Number for this "O-Ring", and where can I order one???

Thanks for ANY thoughts,

Tom
 
Sponsored Links
  #2  
Old 04-19-09, 06:03 AM
Join Date: Jan 2007
Location: MA
Posts: 514
Here is a link to the diagram of your carb the o-rings (2) are reference # 37

PS, the last number in your spec # is not 8 it is B, that may have hampered your search

On this carb be sure to clean small hole in tip of #20 (idle restrictor screw)
 
  #3  
Old 04-19-09, 10:09 AM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Smile Tecumseh Carb Bowl Nut

Originally Posted by smallengineguy View Post
Here is a link to the diagram of your carb the o-rings (2) are reference # 37
Thanks for this, but the link has vanished...

PS, the last number in your spec # is not 8 it is B, that may have hampered your search
Thanks, I discovered my error at about 3am However, I
still am unable to find any info regarding the "Restrictor" in the main nozzle or in the bowl nut.

From what I can find, it appears to be a Series 11 carb (bridged)
which according to a small diagram has a "Restrictor" between the Bowl Nut and the plastic Main Nozzle. This Restrictor is what I need -- I think...

The carb repair kit that I have (632760B) contains a small black rubber disk with a small hole through the center. This is the ONLY part that MAY be what I need. If it's supposed to go into the Center Leg, it's a really tight fit!

Tom
 
  #4  
Old 04-19-09, 11:30 AM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Tecumseh Carb Bowl Nut

I found some additional info...the carb is a Series 11 (bridged) and the part is #640271, which has been replaced by part #640350.

The carb kit that I have is the correct one, i.e. #632760B
Image
The above photo "Image" link depicts the kit parts. I'm thinking that *IF* it's included, the black disk with a small hole in the center is the Restrictor. This piece is located at the top of the photo, and slightly to the right of center.

Any thoughts greatly appreciated!

Tom
 
  #5  
Old 04-19-09, 05:36 PM
Join Date: Jan 2007
Location: MA
Posts: 514
here is the link again.

Parts and Diagrams for Tecumseh 640303-TEC


Your kit appears to be correct. The black disc you are refering to is the cap the covers the idle restrictor screw. The screw it self is not part of the kit. It is a separate PN# 640018. You most likely do not need it, you can clean yours. Once the cap is removed it cannot be put back on, thuis the reason it is in the kit.

Good luck
 
  #6  
Old 04-19-09, 06:26 PM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Thanks for the link! My actual carb part number is 640350-TEC. The diagram and parts list is extremely helpful.

The black disc you are referring to is the cap the covers the idle restrictor screw.
I think that the part to the left of the disk is actually the idle restrictor screw cap. [see photo link below] The cap is definitely included in my kit along WITH the "mystery" flat disk.

Image

"One other thing to watch out for on these carbs is a rubber o-ring sandwiched up at the top of the main jet holder. These can go bad and close up. I found one with a tiny plastic sleeve in the o-ring to keep it open. When I assembled it with a new o-ring and omitted the plastic sleeve, and found it would not start."
Are you saying that the "o-ring at the top of the main jet holder" mentioned in the quote above, refers to the "Idle Restrictor" screw depicted as #20 in the parts diagram? This never occurred to me as the "Restrictor" they are referring to appears in the diagram to be between the open end of the bowl nut and the bottom of the main nozzle...

Tom
 

Last edited by taneal1; 04-19-09 at 06:48 PM.
  #7  
Old 04-19-09, 06:40 PM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Thanks for the link! My actual carb part number is 640350-TEC. The diagram and parts list is extremely helpful.

The black disc you are referring to is the cap the covers the idle restrictor screw.
I think that the part to the left of the disk is actually the idle restrictor screw cap. [see photo link below] The cap is definitely included in my kit along WITH the "mystery" flat disk.

Image

"One other thing to watch out for on these carbs is a rubber o-ring sandwiched up at the top of the main jet holder. These can go bad and close up. I found one with a tiny plastic sleeve in the o-ring to keep it open. When I assembled it with a new o-ring and omitted the plastic sleeve, and found it would not start."
Are you saying that the "o-ring at the top of the main jet holder" mentioned in the quote above, refers to the "Idle Restrictor" screw depicted as #20 in the parts diagram? This never occurred to me as the "Restrictor" they are referring to appears in the diagram to be between the open end of the bowl nut and the bottom of the main nozzle...

Tom
 
  #8  
Old 04-19-09, 06:50 PM
Member
Join Date: Nov 2005
Location: USA
Posts: 467
Tec

The flat disc with a hole in it is a bowl drain gasket which your carb doesn't have.

AJ
 
  #9  
Old 04-19-09, 09:05 PM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Originally Posted by aj-allen View Post
The flat disc with a hole in it is a bowl drain gasket which your carb doesn't have.

AJ
Thanks, AJ!

The Technicians Handbook states that the Series 11 (Bridged) carb has an "added restrictor." The diagrams depict the restrictor located at the top of the bowl nut. It appears to be inserted inside the hollow cylinder of the bowl nut "even" with the top edge. It is directly below the Main Nozzle's lower o-ring. The series 11 carb is a low emissions model so I'm guessing this restrictor has something to do with reducing emissions.

I found a site online discussing "How to Clean" this carb:
"One other thing to watch out for on these carbs is a rubber o-ring sandwiched up at the top of the main jet holder. These can go bad and close up. I found one with a tiny plastic sleeve in the o-ring to keep it open. When I assembled it with a new o-ring and omitted the plastic sleeve, and found it would not start."
The above description doesn't appear to describe the capped Idle Restrictor screw...

I need to find a replacement Restrictor, as it does NOT appear to be included in my rebuild kit.

Thanks for any info,

Tom
 
  #10  
Old 04-20-09, 08:51 AM
Join Date: Jan 2007
Location: MA
Posts: 514
Originally Posted by taneal1 View Post
Thanks, AJ!

The Technicians Handbook states that the Series 11 (Bridged) carb has an "added restrictor." The diagrams depict the restrictor located at the top of the bowl nut. It appears to be inserted inside the hollow cylinder of the bowl nut "even" with the top edge. It is directly below the Main Nozzle's lower o-ring. The series 11 carb is a low emissions model so I'm guessing this restrictor has something to do with reducing emissions.

I found a site online discussing "How to Clean" this carb:


The above description doesn't appear to describe the capped Idle Restrictor screw...

I need to find a replacement Restrictor, as it does NOT appear to be included in my rebuild kit.

Thanks for any info,

Tom
Tom,

This is unclear to me, I believe they are referring to the top "O" ring on the main jet. I have rebuilt hundreds of carbs, I would ignore that quote I think it is confusing a simple issue. Rebuild carb, install new "O" rings, clean the idle restrictor screw and you should be good to go. There may an additional "restrictor" as part of the high speed bowl nut. It is a different PN than the link I had sent you. here is the link to your specific carb.

Sorry about the confusion on the cap AJ is correct the disc with the hole is bowl drain gasket.
 
  #11  
Old 05-13-09, 04:59 PM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
The spark plug remains dry during start attempts.

The fuel bowl has a new o-ring which is properly seated. The bowl fills without overflowing, and bowl nut fuel passages are clean. The main nozzle is not blocked and I've replaced its two o-rings.

I've replaced the primer bulb itself, and after removing the two welch plugs above the float, and the idle restrictor jet, all passages are clear. There's absolutely no sign of any gum/debris/sticky stuff or blockage anywhere in the carb.

Yet, no matter how I push the primer bulb (hold it in and wait 2 secs before the next push, or multiple quick jabs) I can't see any gas coming out of the main nozzle which is visible looking down the carb throat. How much gas should eject from the main nozzle during priming?

Thanks,

Tom
 
  #12  
Old 05-13-09, 07:46 PM
Member
Join Date: Jun 2006
Location: St. Louis
Posts: 2,333
These carbs are terrible for not priming if there is the slightest problem with the bowl gasket. Have a good one. Geo
 
  #13  
Old 05-14-09, 05:18 AM
Member
Thread Starter
Join Date: Apr 2009
Location: Florida
Posts: 8
Originally Posted by geogrubb View Post
These carbs are terrible for not priming if there is the slightest problem with the bowl gasket. Have a good one. Geo
Thanks for the info, Geo. The bowl gasket is new and I've taken care to seat it properly.

Tom
 
Reply


Thread Tools
Search this Thread
Display Modes
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 01:20 AM.