23D issues UPDATED

[Simplicity314 0]

THE UPDATE: Yep, my sarcastic comment was correct--It was something stupid like the manifold gasket--the outside one was missing. The one behind that tin I did put in. Go figure. (The issue with this tractor was I had to put my hand over the air horn and completely choke off the air to get it to run). Put a new gasket on, and after some tinkering she evened out and runs like a charm. I'm just glad the carb wasn't gummed up after sitting since early June. When I did start it, mouse nest materials blew out of the shroud like confetti. I've been pretty good with keeping up the mouse trapline too! This doesn't bug me as much as it usually would since I did hear some rubbing of the flywheel or something bolted to it against the shroud anyway, so something's amiss and it has to come off anyway. Thanks for everyone's replies. The original post is below. Okay...I got a new battery for my 7016, a car battery, and I want to use it to troubleshoot my 64 LL with a 23D, battery ignition. I can't afford to keep killing batteries trying to get this thing running! (and I mean minimal cranking--this machine just kills them), so I want to run by everyone as to what's happening to hopefully shorten the chase. To start it, I need to completely choke off all air by holding the palm of my hand over the air horn. Once it's running, it will run but only at full choke. I can start to open it just a crack and it will keep running, but only at full throttle and even then it's idling low and wants to stall. I did this with a completely rebuilt carb, then, figuring it was the carb, I took it off again, re cleaned it and replaced the intake gaskets while I had it off. Exact same issue. Obviously I'm getting plenty of spark and fuel at least when I choke off the carb. I don't know what to rule out. I've rebuilt lots of these carbs with no issues, so I'm leaning away from that. I know this also sounds like a valve issue, but it was running strong when I last parked it (which has been a couple years now). I know engine performance will degrade over some time when valves start leaking, but this was sudden. OTOH, it's drawing in plenty of air from somewhere, given how strong it runs when it's completely choked off. sm00 Any suggestions as to where to start? Thanks in advance.

[UCD 8]

Jim Sounds like you have a vacuum leak either at the throttle plate shaft or gaskets between the carb and manifold or between the manifold and block. When you rebuilt the carb did you thourghly clen the jet passages with carb cleaner and compressed air? Also have you checked compression Low compression also equals low vacuume requiring more air restriction to pull gas in to the cylinder. This could be caused by bad rings and/or a burnt or sticking exhuast valve. To check for the vacuume leak around the carb and gaskets take a spray bottle and spray water around the throttle shaft and gasket locations one at a time while it is running if it improves you have found your leak.

[rm 0]

a trick ive learned, that helps, put rtv silicone on the gaskets for the intake, it helps seal the intake, it works good on old gaskets too.

[MrSteele 270]

The manifold to block connection carries 2 gaskets, one outside the throttle control plate between the manifold and the plate, the other between the plate and the block. Are both in good shape and making a good seal?

[3314WV 0]

By having to hold your hand over the air inlet you may have a sticking valve issue.....just a little shot of WD-40 in the plug hole may either prove or disprove.....had the same thing recently on an 8HP briggs.....after a little WD no more sticking.....

[Simplicity314 0]

Mr. Steele--thanks--I'll check that when I take it apart. It's probably something stupid like a missing gasket. 3314--I thought it might be a valve issue like I said. The engine feels like it has good compression when I turn it by hand. I'll be doing a compression check as Maynard suggested either tomorrow or sun. I'm going to double check my carb and intake seals first and if no dice, I'll be looking closer at the valves. rm-- using gasket sealer crossed my mind since I'm sure every surface is warped on a machine going on 50 years old.

[ketchk 1]

i know you can check the valves with a leak down tester basically it just shoots air into the spark plug hole and you listen to see where it comes out if out carb its a intake valve if exhaust and exhaust valve ect.