Tillotson/090 question

[user 2993]

My 090 has a tillotson HL244a carb which I suspect is not the original. The parts list gives other carb #'s, and the adjustment screws are in an awkward position. Also, the saw only runs right when the screws are turned almost all the way in.
Any suggestions or info would be appreciated.

Thanks,
George

 

[rupedoggy]

I have seen that carburetor on 090s. There were two positions for the adjustment screws (side or front) and there does not seem to be any continuity from saw to saw. If your saw needs the adjustment screw turned way in to function properly, I would suspect the needle/seat to be leaking or the lever height to be set too high. There could be some leakage around the adjustment screws from previous overtightening but that is rare. It is time for a complete rebuild of your carburetor. Mike

 

[z4lunch]

090

George,
Steve here... Mikes on it... My 090 didn't run real well and was oblivious to mixture changes too. Put a new carb kit in it and it starts idles and runs awesome...My old diaphrams where like cardboard they were so old and dryed out. I believe my carb is also marked 244. Mine dates from the middle 70's. Carb mixture screws are out the front
Steve

 

[user 2993]

Thanks guys. That narrows it down a lot. I actually did tear down the carb when I got it because it was running real bad. I just cleaned all the parts an reassembled it with a new carb kit. So it is probably something to do with the functioning of the needle, as Mike suggested. I think I put a new needle in, though.
Mike, could you explain a little more about setting the lever height?

Thanks,
George

 

[rupedoggy]

The big diaphram, that has a button in the middle, is the needle "mover". It moves one end of the inlet lever and the other moves the needle on and off the seat. The lever must be set flush with the floor of the carburetor. If it is not exact you can bend it a little. If the button in the middle of the diaphram is the notched type, it usually will fit into a corresponding fork in the lever. Failure to engage the fork/lever will result in an improper height and flood the engine (or possibly you would have to turn the screws almost all the way in!).
If the spring under the lever is not original you must replace it with an original of proper tension. People that rebuild lots of carburetors have a pop-off gage to get proper tension. Without it your best bet is the original replacement tensioned spring. Mike

 

[user 2993]

Thanx, Rupe!
Now that I think about it, I recall that spring leaping across the room never to be found again. I replaced it with one from another carb that seemed about the same size. Guess I'll get another kit and try it again.

 

[Marky Mark]

Hey Mike when you rebuild a carb do you always use gasket sealer for the diaphram??

WoodBeard Becareful what you read on the web, of course that's comming from an armchair chainsaw builder.You might end up with one of these.

 

[user 2993]

Mark, I understand you and Mike have a bone to pick, but with all due respect, I'd rather be left out of the pickin'.
Mike's Info on this subject sounds solid to me. If anyone has other relevant ideas/suggestions, the topic is still open. That's what a forum is about, right?

 

[user 2993]

Pulled the carb this afternoon, and did a little tinkering. That lever was indeed a little high, and I could see how this was letting the needle be pushed off the seat. Bent it so it was even with the floor, and the needle was snug in it's closed position, and put everything back together.
Works perfectly now! Both screws are around one turn out, and more importantly, they actually do their job now.

Thanks again Mike,

George

 

[rupedoggy]

Glad I could help and thank-you also George. Mike