McCulloch Leaking Filter Bowl

[LaqueRatt]

My 14 HP McCulloch seems to like to leak around the gasket. Replaced it earlier this year with one I cut from cork/rubber stock from the auto parts. Worked like a charm. For awhile. Then it started leaking again. So I cut another gasket and doubled up. Worked fine for the rest of the season. Today when running it dry for winter storage wouldn't you know it's leaking again. Took it apart and re-positioned the gaskets. Still leaks. Used pliers to tighten it more. Got it down to a slow drip, but still leaking. I think the thumb screw may be a bit stripped. Another gasket? Anybody got a better idea?

 

[robert graham]

Maybe an o- ring of appropriate size would be better?

 

[LaqueRatt]

I guess that's an option, but I'm thinking an O ring of the correct size may be hard to find. The bowl is about 2" across. I had a paper gasket for a Chevy water pump that was the perfect size. Didn't work. Cut one from some standard, but thick paper gasket material. It leaked like crazy too. Doubled it up, still leaky. The cork/rubber material is similar to the old gasket I pulled off, but it seems to only work at first, or at least when the motor is run regularly. Was pretty shocked to see gas pouring out again after having it sit for 3-4 weeks. It was fairly cool out though (50 degs), so maybe that's a factor. I'm tempted to use some sort of gasket cement on it, but then if ever needed to get it back off I might regret it.

 

[racerone]

??----Why do you think an o-ring would be hard to find ?-----Should be easy to repair the thumb screw so that it tightens properly.----I would concentrate on that easy repair !

 

[LaqueRatt]

Why would it not be hard to find? I don't have an old one to match up you know. The original was cork. The local hardware carries O rings, but this is bigger than your typical O ring. I have a couple assortments but they are the size of a nickel and smaller. The bowl is about the size of half of a golf ball.

The thumb screw gets pretty tight, but when I put pliers to it I think it's slips. The double gasket seems to be an improvement.

 

[Scott Danforth]

I have o-ring kits that go up to 3"

Local Ace hardware has stock up to 4"

McMaster car sells O-rings up to 1.5 feet in diameter, from there you make them

 

[LaqueRatt]

How do you make them? Seems like you'd have to fuse the ends together somehow or it would leak where the ends meet. I also tried unsuccessfully to make a rubber gasket out of inner tube.

 

[Scott Danforth]

The point is a 2" o-ring is going to be common. I would suggest a quad-ring.

Many NAPAs have them in stock

And there is always McMaster

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[LaqueRatt]

Wow, cool. Thanks for the link. The only experience I've had with larger O rings is for oil filters. Guess you boat guys use them a lot more than car guys.
Oh wow, looks like I just advanced in rank! Shouldn't I also get a bump in my pay scale? LOL

 

[Scott Danforth]

Wow, cool. Thanks for the link. The only experience I've had with larger O rings is for oil filters. Guess you boat guys use them a lot more than car guys.
Oh wow, looks like I just advanced in rank! Shouldn't I also get a bump in my pay scale? LOL

Im a gear-head with a background in mobile off-highway, diesel engines, cranes, marine hardware, etc.

there are a lot more o-rings on a car than in a boat. then again, there are hundreds more on a hydraulic laticed boom crawler crane than a car.

regarding pay. you will get the same pay on iboats that I get..... we are paid in smiles

 

[racerone]

Very few appreciate the level of help offered here.-----It can be frustrating helping on some simple issues.

 

[LaqueRatt]

Have to say I agree with you. It's a bit of a odd mix on this forum and noobs sometimes aren't too well tolerated. Good bunch of guys though and amazingly helpful......most of the time! Thanks to you all. I learn something here every time I log in.

 

[flyingscott]

isn't that a flat gasket? If it is make sure that groove is spotless. Then go find a rubber flat washer that is fuel resistant

 

[LaqueRatt]

Yes, the gasket I removed was flat. Not sure if original but it was made of cork and promptly turned into a potato chip after it started to dry out. I bought some gasket material that was as close as I could find and cut a new one. Worked great at first, but ever since I took that fuel bowl off I've been plagued with leaks. I did not clean the groove though. I'll give that a try. Funny that it would seal perfectly and then later leak though isn't it? I'm tempted to try one of the rubber ones from McMaster, but I have no way of knowing if that gasket would be anything like the original or if it would likely work.

 

[dingbat]

Found these to fit the bowls of many carbs used on small engines, IE golf carts, lawn mowers, etc.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[LaqueRatt]

Would you say these are better than the X shaped ones in the link Scott posted? Just finishing up getting ready for winter. Hoping to get this motor back on the stand next week for some minor tweaking. Dug up the missing reverse lockout lever which I need to install. Hopefully the days of the motor trying to jump into the boat with me will now be over.

 

[dingbat]

Would you say these are better than the X shaped ones in the link Scott posted?

X-rings are typically used in reciprocating applications to reduce friction. In static applications, they typically fall short because of the reduced contact of the cross section.

Having said that, each ring profile requires a different groove profile. Using a X-ring in a groove designed to accommodate a O-ring or a Square ring may not perform as expected. The best seal will always come from a groove designed for the particular ring type.

Ring (profile) sizes typically don't over lap. What you will probably find is that the diameter, width and depth of the groove will determine which ring you use

 

[LaqueRatt]

Would this work? Seems to be the correct size. Don't see where it says is specifically works with gasoline. Also wondering how thick it is. Maybe I missed that spec?

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[LaqueRatt]

Would these be a better choice? They are the same dimension but says takes less pressure to make them seal. That it has two lips so it's less likely to leak:

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[dingbat]

Would this work? Seems to be the correct size. Don't see where it says is specifically works with gasoline. Also wondering how thick it is. Maybe I missed that spec?

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Neither match "the bowl is about 2" across" comment.

Get a pair of calipers and measure the depth and inside and outside diameters of the groove on the bottom of the carb. Those three dimensions will determine which o-ring to use