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super h carb rebuild needle valve questions

J

jpapier

Member
Got a kit here to rebuild a super h carb(358065R91). It has three seals(my best guess,no instructions)for the high speed needle valve, a rubber tube and two felt tubes of different lenghts. I will use the shorter felt , the others seem way too long. What I pulled out was plumber's cord.
My questions concern these adjustments. They seem too lean.
The idle screw was one turn out, the slow speed needle valve one half turn from bottom, and the bottom high speed valve was three turns out.
To get the tractor to run at the auction, it had to be at half choke.
 
It sounds to me like the kit you got did not include the graphite packing gland for the high speed idle screw. This is what you need. Nothing else will work. Those two pieces of felt do not belong anywhere in that carb, and I have no idea what that rubber tube is. The low speed idle mix screw is set at 1 1/2 turns out, but needs to be adjusted while the engine is running for optimum performance.The high speed idle mix screw is set at 3 turns out.
 
As you say 3 turns out on the main jet is too lean. Open it to 3.5 or 4 turns. Max power is 5 turns out, it can be turned in for better fuel economy. At 5 turns the tip of the needle is outside the seat. There is no "sweet spot" on the Super H/M carbs as there is with the regular H/M. The idle speed is set so that it runs smoothly. The idle mixture is turned in or out until smooth.
 
On identical tractors the carb mixture needle settings can vary widely from one tractor to the next!

I have a pair of Super H's. One requires 3/4 turn open on the idle, and 4+ turns open on the high speed. The other needs about 1 and 2-1/2 turns open respectively.

NOTE! On the SH carb the idle screw works opposite from the high speed screw - turning the screw IN makes the idle richer.

----

The carb idle stop screw is simply that - a mechanical throttle shaft stop that sets the low idle RPM. Simply turn it in/out until the engine idles at the speed you want (450 RPM or so for the SH...)

----

That small felt you found in the kit may be the drip hole filter. It fits into a hole in the boss at the bottom of the air passage beneath the choke plate. The filter is retained by a small, pressed-in washer.
 
Well RF, I wish they would have had a parts list with the kit just so I would have some idea of what parts are supposed to be there!
 
A parts list included in the kit is a thing of the past. None of the aftermarket kits have that anymore. Also, as I mentioned before, those two little felt pieces are included in every kit, but they DO NOT belong in a Farmall carb kit because those carburetors NEVER had such a thing in them. Also, The packing gland that is missing from the kit was never included in that kit, even though it should have been. It is NOT your fault. It is the fault of the folks that put those kits together and then market them to folks who are in-experienced with such things. As a way out of this mess, that packing gland is available from Case-IH at a price of about $4 if I remember right. It is part number 24703DA
 
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