Yazoo with stuck carb bowl gasket Original Message Jul 20, 2014 10:51 am
I need to clean the bowl on a 7 hp Briggs updraft engine (80's vintage), however the gasket around the top of the bowl is not letting me remove it. I did already take out the long brass jet tube. Any idea what's holding this together? Model 170402 Type 2155 Date 84062812 I purchased the Carburetor overhaul kit (394693) however I the old paper gasket just does no want to come free. If I whack it any harder I fear that I may break something. Is there a secret to getting these apart? This engine runs a 24" Yazoo made for Troy-Bilt called a "Pro." The Yazoo and this engine have not been run in 8 years. The carb jets were pretty gummed up and the paper gaskets are very dry.
I figured out the problem. Someone used some RTV (sealant) to glue the choke housing onto the carburetor. They may have had a leak or drip down below the choke and thought this would solve the problem. Not sure how to disolve the RTV? Maybe brake cleaner?
Re: Yazoo with stuck carb bowl gasket Reply #2 Jul 21, 2014 8:17 am
I tossed the whole thing in a bucket of gas last night. I will pick up some brake cleaner today and try that. While I was cleaning the long brass emulsion nozzle tube(power jet) I noticed that it was tarnished a one specific spot where it is supposed to seat tightly. As if gas was sneaking past. I think what has been happening is that the brass emulsion nozzle(power jet) does not seat and seal properly and allows gas to leak down to the choke and dribble out when the engine is shut off. I had a similar Briggs engine on a leaf blower that would do this. I either had to shut it down by turning off the gas and running it dry or leave a small plastic cup under the choke to catch whatever leaked out from the carb after it shut down. It was never a problem while it was running, just at shut down. I don't know if there is a fix for this. Some way to get the long brass emulsion nozzle tube(power jet) to seat and seal. This image was not created by me:
This message was modified Jul 21, 2014 by Underdog
Those carbs are a big pain, they start easy with the updraft design, but the cast aluminum bodies rot out if they get moisture in them for too long. the whole thing has to be taken off to work on it or clean it out. and the carb ahs to be split in two to flush the thing out or change the needle and seat. or to adjust. I always throw a new needle and seat when I take them apart.. and set it in a vise with fuel flow to watch it for leaks before reinstalling on the engine.... also a good idea is to install a fuel shutoff if the fuel line does not have one, that way you don't end up with a gas puddle under where you park it. Friiy