M\S Carb Wrong Main Jet?? -- CA
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Topic: M\S Carb Wrong Main Jet?? -- CA
Posted By: Turbo_760
Subject: M\S Carb Wrong Main Jet?? -- CA
Date Posted: 06 Jan 2012 at 8:32pm
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Working to sort the fuel issue out on the CA ( I have a couple of post about it), I have ruled out fuel supply as I have test tank and new line.
Someone mentioned that my main jet could be plugged or the wrong one...
TSX154 M/S this is the main Jet/Nozzle in the carb it insn't plugged but looks different then the replacement ones
 Below is an image from OKtractors of the TSX154 Jet.... I have assumed that this is a picture of the actual part
 Comparing the images the nozzle that I have has a smaller tube and more holes compared to the OK tractors one. Mine appears to be the same diameter as the OK tractor one where it is steps down in size at the bottom.
Do I just have an older version or do I have the wrong jet..... (hard to believe it could be the wrong one, but this tractor has a few special tweaks from the previous owner)
Could someone confirm which jet is correct for CA... Thanks!!!!
------------- 1951 CA Cub Cadet 149 |
Replies:
Posted By: Chalmersbob
Date Posted: 06 Jan 2012 at 9:39pm
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That is not the main jet. It is the discharge nozzle. But it should have the same holes as the example. They may be blocked
The main jet is at the bottom of the carb. Remove the drain plug and look inside there.
The main jet gets removed with a screwdriver. Bob
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Posted By: Turbo_760
Date Posted: 06 Jan 2012 at 10:41pm
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Alright.. I think I need a little more help understanding this carb
This is a picture of the bottom of the bowl.
#1 is the drain plug and that leads to 2 small passage at the bottom of each half the bowl
#2 this is a plug which if I remove it goes right into the discharge tube... I found this filled with black sludge, after cleaning it out I can see all the way through the carb
 This is a picture of the top side of the carb
#3 Is this the main jet? I have removed this and cleaned it out good
#4 this is were the discharge tube goes. There doesn't appear to be any orfices in here, just some sludge and this connect to the small brass plug in the pic above (labeled #2)
#5 this little passge is the drain and connect to the drain plug below.
 Do my assumption above seem correct? I think that I have now found the main jet ------------- 1951 CA Cub Cadet 149 |
Posted By: Soilguy
Date Posted: 07 Jan 2012 at 9:11am
| You might look at the website below. It's written for Ford tractors, but I've found the sections on carburetors very helpful. It covers the anatomy of both Marvel Schebler and Zenith carburetors, and the adjustment section was a life-saver for me last year. Just a suggestion. Good luck, Larry www.myfordtractors.com |
Posted By: Dick L
Date Posted: 07 Jan 2012 at 4:17pm
| Number 3 would be the main jet on that carburetor. If you had the adjustable type the needle would screw into the top of the carburetor and the point would go thru the hole above the #3 jet to close it down or open it up. Different jet though than what you have now. I have a set of wire drill bits and when I boost the air flow thru a built up engine I open the hole in the jets. When I do this I do not enlarge the hole very much before I try it out under load. I use a pin vise to hold the drill and open them up by hand. |
Posted By: Steve in NJ
Date Posted: 07 Jan 2012 at 8:02pm
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Small bore Marvels like that one have a "fixed" main jet in them. Large bore M/S carbs have an adjustable enrichment circuit in them. If you're still finding debris in that carb, it problably still has debris in it yet. If there's a machine shop near by, the best thing you could do is drop it off and have them glassbead the inside of that carb like I do when I rebuild em' for our customer's, and get all the crap out of it. Nothin' like glassbeading them old dudes to get the muck out of em'. The discharge nozzle you're comparing to may not be the correct replacement for that carb, but in most cases, replacement carb parts may not look identical either, but still do the same job. It has to do with patents and such... Steve@B&B |