I have a 1928 cat 30 and I was wondering if anyone had the information on how to adjust the carb. ( what screw does what)
Thanks.

Hi criscokid,
scan below is from my General Instruction Book For Early Cat Products.
Hope this helps.
Cheers,
Eddie B.

thanks,
My machine is hard to crank, I hope a slite adjusting on carb will help. do you know if you should prime the carb untill gas comes out the bot drain, or do you just pump it a few times to get you started. Also i was wondering what the two (oil cups ) are on top of the engine are for, at least they look like oil cups. There appears to be some linkage missing on mine. Thanks for your help as I just got my machine on Monday, she runs but needs some tweaking.

The carb on my 1928 model Thirty is a bit different than the one on the sheet provided by Eddie. My carb has no choke (I believe the choke was added a bit later) and the throddle arm is on the opposite side, ie. with the fuel inlet on the right side as looking at the carb as mounted on the engine, the throddle arm is between the carb and the engine. Basic adjustments appear the same. It should start ok with a simple priming (see priming cups below) and once started I normally adjust the knurled knob (hi speed needle) until I get a minor amount of exhaust smoke then screw down on the jet until it cleans up.

The two oil cup looking thingies are how the earlier Cats are primed. The Thirty has two different locations for priming cups. You may have both on your engine if your intake manifold has been replaced in the past.

One location is on the head just above each intake port (2 cups). These cups are connected by a 3/4" x 1/8" bar stock of the appropriate length but not really necessary because the cups can be opened and closed individually. The priming cup has a cover made into the lever and after you pour in a little gasoline drops the fuel into the manifold when you move the lever back into its covered position.

The other location is found on some of the intake manifolds. The cup type is different from the head mounted cups and not connected by a linkage. The cup is designed in two parts that allow you to pour the gas in the cup and then screw the top to drop the fuel into the manifold. There is no cover on this type cup and you have to screw the top part back to close and prevent a intake manifold leak.

If you have the cold weather package for your Thirty, it will have two holes in the hood, one hole above each of the head mounted priming cups. Its a pain in the butt to prime with the hood in place.

Hope this helps,
Tom

On the Thirty that I run several times a year I usually push the primer on the carb until gas runs out the bottom of the carb. It will then usually start with three or four pulls of the crank. If it has sat all winter then I will put a little gas in each of the primer cups before trying to start it. Each tractor has it's own way of liking to be started.
Thanks
Ken

Thank you both for your input, As I have just purchased this machine I am still learning the ins and outs of the machine.

By the way was all the thirtys painted grey if not what year did they go to yellow( just curious)