Farmall Cub Forum -- Questions and answers to all of your Cub related issues.
Moderator: Team Cub
Notice: For sale and wanted posts are not allowed in this forum. Please use our free classifieds or one of our site sponsors for your tractor and parts needs.
The cub I just purchased needed a carb rebuild (according to the previous owner) as it wouldn't idle. He hadn't tackled that sub-project before his heart attack slowed him down.
No problem, sez I, I'll read up on the IH carb and git-r-done. So I read every thing I could find on the subject - most of it located on this site and very comprehensive. When I pulled it apart, the first thing I noticed was the broken & missing idle tube. Aha! Very Common. But what puzzled me was the lack of a main jet... I mean it wasn't there... no hole in the bowl for one, either. Temporarily skipping that, I stripped everything down and after an overnight solvent bath and two hours in the heated ultrasonic tank I noticed a faint impression of where the main jet SHOULD have passed through the outer wall of the bowl. As it turns out, someone, years ago, had broken off the main jet at the end of the threads. Noticing that fuel would leak from the outside hole in the bowl, they plugged it by hammering in what appears to be lead fishing sinkers and dressing the outside flush! However, it did work and it didn't leak, so I guess I can't argue with the utility of the repair. LOL! After drilling out the main jet and re-tapping I resurfaced the area where the main jet gasket contacts the outside of the bowl.
Also noticed the upper housing was warped from overtightening. Having seen references to several plates online here I made my own. It works very well.
Flipped the plate upside down and used it as a jig to hold the upper housing square while I drilled out the broken idle tube.
Now we wait until my rebuild kit arrives from Steiner...
if you ever decide to make more of the carb jigs put me down for one
Me too...how much????
'50 H, '52 Super C, '54 Cub, '57 Cub, '58 Cub, '95 Cub Cadet
Is the main jet broken off inside? It goes through the housing, where you found the lead patch, and threads in further inside. I doubt it would have run, without that end. (the actual jet portion) Ed
50 ,52,53,56,59 F Cubs, 55,55,57,63,63 fast hitch, 64 lo-boys, 71 154, 184 lo-boy,61 cadet original. IH spreader,IH corn grinder, Oli. OC3 ,AC D10 ,IH 444 , Potato digger, wagner ldr 3 power units.
Nothing like solving a mystery!
"Chance favors the prepared mind."
- Louis Pasteur
"In character, in manners, in style, in all things, the supreme excellence is simplicity."
- Henry Wadsworth Longfellow
Because you did all that reading I am sure you noticed that the idle tube is a somewhat uncommon 4- 48 thread.
It looks like a nice clean job you did. When I saw your tools and the can of cutting oil I expected it to be so.
"Life's tough.It's even tougher if you're stupid."
- John Wayne
" We hang petty thieves and appoint the great ones to public office."
Add me to the list
Nicely done I am impressed with your jig. Nicely done If you have a measured drawing it would be a nice addition to the server, the CBoK and the How To Forum. Interesting use of the jig to drill and re-tap the idle tube
I'd like a jig too. Please put me down on the list
That's true. What I was trying to describe is that at first glance, there was no main jet, or place for one - when in actuality, it had broken off inside right at the end of the threads. This left the threaded portion (and orifice) stuck inside.
Thanks, I did note that while researching. Thought I had that one, but ended up ordering a set after I discovered the ones I had were 6-48, not 4-48.
Thanks, Rudi! I worked off a simple sketch. Will clean it up and develop an AutoCad version for the site - that's the least I can do for everything I've learned from you guys.
I love it when a guy says "git-r-done," then whips out a Bridgeport, a can of Tap Magic, and Autocad
My idea of git-r-done is an oxy-acetylene torch, a 2lb cross-pein hammer and a roll of duct tape
Who is online
Users browsing this forum: Xperimental and 5 guests