Does anyone have the carburetor float level setting for the pony on my recently acquired 1949 Cat D-4 Serial 6U-2831? Cleaned the carb. and installed a new 1/4" copper gas line, gas filter and shutoff valve. Now the pony doesn't get enough gas to keep running. The original problem was that gas would overflow out of the carb. bowl joint. I made a new gasket and guessed at the float level adjustment but probably have it wrong. Bought an Owner's manual but it doesn't give the float spec.

I bought this machine a few weeks ago and am just getting into a thorough checkout. The hydraulic fluid was low so I added regular hydraulic fluid. Apparently it's not compatible with whatever is in the reservoir as a grey-colored fluid oozes out from around the control shaft on the pump reservoir. Does this sound like water in the hydraulic system?

Thanks again for any help.
tinytec aka Fred in upstate NY

Take the top off the carburetor bowl and turn it over upside down. The float should be parallel with the "top" of the bowl as it rests on the needle.

Then while you have the top off, remove the bowl from the side of the carburetor and remove the main jet (that the adjustment screw seats in) and clean it thoroughly. then remove the hex plug on the bottom corner and screw out the metering well jet and clean the tiny holes in it and clean the passages back to the main jet and on to the carburetor venturi. Then there's one more while you are there, the idle circuit jet is in the bottom of the bowl, remove and clean. Also remove the idle needle and clean/blow through. Reassemble and adjust the 2 mixture needles a couple turns from seated all the way in.

When you run the engine, if you need more fuel, adjust the needles IN, not out like the common small engine carburetor. Yes they are both backwards!

The D6 pony has only the idle mix needle that works backwards.

Grey hydraulic oil usually means water. Whatever you added may have had some detergent ability and "found" some water or other contamination in the system and now it's circulating instead of laying in the bottom of the resevoir. Time for a fluid and filter change ASAP!

Occasionally a high pressure internal leak or a suction leak will entrain enough air into the oil to make it cloudy. I wouldn't bet on it though.

Your tractor should have the 5F3527 carb. Others will fit but they have their differences. Float spec/instructions attached. The #44 unit calls for crankcase oil, not hydraulic fluid. Same as 30wt for engine.

OM if he sets the float as CC said just parallel with the top cover when it,s upside down it will be plenty good enough.I & the others at the shop set dozens of them that way & they ran perfect.Fred you want to use #10 oil in the hydraulic same as the engine oil but 10 weight in our colder temps. back in the north east here. The 10 was what we always installed at the shop & was recommended for here.

Hi SJ,
He asked for the spec on float setting. Either setting method is fine.
Correct on the cold climate hydraulic oil usage.
I have also found the newer viton needle/seat combination tends to stick so I have gone back to the all metal version. There's just not enough head pressure in the fuel supply to push the valve open I guess.

OM,
I have written down in the back of my #44 book
7F7238 filter and also
2A5886 filter (also a fuel filter for something?)

What's the story on this?

Hi CC,
Early #44 units 7W607 and prior used the 2A5886 filter which was the same as the old rope wound type fuel filter element. The later units used the 7F7238 cartridge type element (in the metal perforated can) which is much more pricey and harder to find plus there doesn't seem to be an after market replacement.

It's would seem to be desirable to go back to the old style but you need the matching hanger parts and cover plate to do so.

Yes OM that new style needle & seat was not too hot an idea when they came out with it & as you said won,t hold up like the old metal to metal ones did.

Hi Everyone!

Thank you so much for all the fine information and even the diagrams! Dumb me - I didn't realize there was a throttle valve and much more to the carb. when I worked on in the float area. At one point I was going to remove the entire carb. but did not because of the many other outside units that were in the way.

As for the hydraulics - I'll have to drain and put in new oil - sure don't want to damage that pump!!

I'm scheduled for cataract surgery this week so may not get to work on the Cat until the old eyeball settles down.

Will post the results from your most valued guidance when she runs.

Thanks again friends,

tinytec aka Fred in upstate NY

Fred you won,t believe how well you,ll see when you get yours operated on. I had one done about 3 yrs. ago & I,ll need the other one done in the near future.They used the lazer I guess you call it & I was in & out in a couple hours.I am a little far sighted in it but at least I can see good out of it now.Your only a little over couple hours away from me, I live in Dallas Pa. just west of Wilkes Barre Pa. I worked for the Cat dealer in Wilkes Barre for 36 years but been retired 15 yrs.last Dec.from there.We worked up that way a lot when they were building I-81 highway.I,ll never forget this one contractor was in the New Milford area on the highway & every morning this one foreman kept parking his little car right in front of the fuel pumps so the dozers & equip. couldn,t get into them to fuel up. This one operator told him if it was in the way another day he,d run over it. Well guess what it was parked in front of the pumps the next morning & the operator clumb up on top of that little car with a D9 dozer & then turned around on it.About all that was left was a flat piece of iron.I didn,t see the car but the picture I did that came out in the daily newspaper.I guess that taught that guy where not to park from then on.