Briggs 5HP tank mounted carb leaks where mounted.

[JoeM 7,874]

I have this tiller engine, 5 hp Briggs. The carb is a pulse jet and is mounted to the top of the gas tank. 

For the life of me I can not get the gasket to seal. 

The top of the tank is straight, the gaskets are new. Everything looks good but it continues to leak in the corner of where there is not a lot of gasket. 

I doubled up the gasket, used shellac. I just think there should have been a screw in that area. 

Anybody got any tips, different gasket material, glue etc. 

I have had this thing apart a half dozen times.

 

 

 

[wallfish 17,000]

You can try to double the gasket or pick up some thicker gasket material and cut a new one.

Typically sealing them isn't always the best option but it is the easiest. This product works well for sealing against gas

https://www.acehardware.com/departments/paint-and-supplies/tape-glues-and-adhesives/glues-and-epoxy/10840?x429=true&msclkid=a6f0fa1547251d0e3020988fe4f53f3d&utm_source=bing&utm_medium=cpc&utm_campaign=PLAs_FF4-Paint-Sundries_Paint-and-Supplies_Other_All_Other&utm_term=4581939838674219&utm_content=Paint-and-Supplies_Tape-and-Glues-and-Adhesives_All_All&gclid=a6f0fa1547251d0e3020988fe4f53f3d&gclsrc=3p.ds

[wallfish 17,000]

You can try to double the gasket or pick up some thicker gasket material and cut a new one.

Typically sealing them isn't always the best option but it is the easiest. This product works well for sealing against gas

https://www.acehardware.com/departments/paint-and-supplies/tape-glues-and-adhesives/glues-and-epoxy/10840?x429=true&msclkid=a6f0fa1547251d0e3020988fe4f53f3d&utm_source=bing&utm_medium=cpc&utm_campaign=PLAs_FF4-Paint-Sundries_Paint-and-Supplies_Other_All_Other&utm_term=4581939838674219&utm_content=Paint-and-Supplies_Tape-and-Glues-and-Adhesives_All_All&gclid=a6f0fa1547251d0e3020988fe4f53f3d&gclsrc=3p.ds

[Skwerl58 704]

I had the same problem and couldn't get the leak stopped. Called a local shop and he said bring it by and drop it off. Next day he called and said come pick it up. I asked what he did and he said new gasket and sealant and charged me $30.00. Hasn't leaked a drop since and I did the same repair he did. Go figure, must be the sealant he used.

[OutdoorEnvy 1,522]

I have the same engine on a tiller, an old Dayton, same issue as you so will be interested to see what may work.  I rebuilt the carb and all new gaskets, etc as well and that annoying leak drives me nuts.  Good topic!

[ranger 1,750]

Are the tank or carburettor surfaces distorting when you tighten the mounting screws? I have found adding extra/ thicker gaskets can sometimes make matters worse, particularly if one surface is more rigid than the other. Do you have a torque figure for the screws? You could try assembling it dry, and just ‘finger’ tighten the fasteners and see what happens? I think many ‘leaks’ occurring  on equipment, (especially if cork gaskets are involved) are due to ‘over-tightening’ on assembly

Doug.

[JoeM 7,874]

1 hour ago, ranger said:

Are the tank or carburettor surfaces distorting when you tighten the mounting screws?

Hmmmm, I will have to take a closer look at this today. 

The entire assembly is held in place by the two carb bolts and one bolt on a bracket at the very lower end of the tank. If the lower bracket and carb bolts are not in the same plane, it could in theory cause the rear of the carb to gap open.

 

I think I am going to check the alignment, get some seal all, and a new gasket.  

 

I'll be back.

 

 

Edited June 4, 2022 by JoeM

[OutdoorEnvy 1,522]

I think the idea of a gasoline rated sealant applied to both sides of the gasket sounds promising.  I may give that one a go myself. 

 

It really does look like one more screw hole would have avoided all this trouble...engineers...

[Jeff-C175 7,202]

I would probably try a silicone product such as "The Right Stuff" and run a bead all the way around... wait until it 'tacks up' before tightening the mounting screws to give a little bit thicker gasket.

 

 

[JoeM 7,874]

Update

i checked the alignment when tightened up and sure enough it gaps open a touch. Bent the lower mounting tab so it would put pressure on the joint. Helped a lot but still seeps. I got that seal all, but no new gasket. I used a good used one and the seal all waiting till tomorrow to try it. 
the vid is when I pushed the bottom mount  to frame to see if it helps seal. 
I would have used a new gasket but did not have the right material to make one and the nearest store with the material is  13 miles away. 

 

Edited June 4, 2022 by JoeM

[JoeM 7,874]

Update, got it sealed! 

 

Used a OEM gasket and Permatex Motoseal.