I have a 1974 Wheel Horse that is a project we work on o for fun. We rebuilt the K-181 that came with it...had some governor problems that just got straightened out and now the fuel tank is leaking.
The tank is plastic with a rubber bushing on the bottom and a metal valve. The original bushing was cracked and while it leaked, it was just a few drops but enough to warrant repair. I went to the local Bob-cat, Toro, Scag dealer and he didn't carry the exact parts but had a triton bushing that was the same size as the original so I tried it with the original metal valve. The valve popped into place but once the tank had gas in it, it started leaking severely.
I went back and got a rubber bushing. They did not have the metal valve in stock so I got a plastic valve that was made for some Toros and Bob-Cats and it popped into place much firmer. It appeared to have the bushing up against the bottom of the tank but it also ended up leaking. I cannot tell if it is leaking where the bushing goes into the tank or where the valve goes into the bushing. I have also sanded some of the rough areas where the bushing goes into the tank. I have also installed the valve using carb cleaner to lube the valve.
Any other ideas or if this can be stopped? So far the tanks that I have seen online look to be in worse shape than the 1 I have so any links to a universal tank or something that would fit. It is a B-80 mower.
Carb cleaner is exactly the wrong thing to lube with as it attacks most plastic & rubber.
It was designed for zinc & aluminium carbs with brass floats.
This is why Walbro has spent a fortune formulating a cleaner that is safe with PVC , Nylon, Vitton & buytal .
Rubber grease is the stuff to use if you need to lube.
What is the diameter of the hole in the tank
what is the diameter of the tap you are pushing through it.
I thought so too I usually use a small dab of Dawn or just a bit of 30 weight oil. He told me that was all wrong and to spray the valve with a bit of carb cleaner to get the grommet to draw around the valve.
The part number for the grommet I have is 1654930SM. It is a Briggs number. The Toro part number that originally came with the mower was Toro 46-6560
3/8 ID 1 1/16 OD on both
The part number of the valve I am using is Bob-cat, Bunton 38540. The original valve part number is Toro 104048. I cannot find any specs on either one but the measurements are as follows
Bob-cat:
flange 7/16
Barrel diameter 3/8 (part that is in the ID of the bushing)
Top 9/16 (part that rests on the top of the bushing)
Barrel length 9/16 (between flange and top)
This was done with a ruler and is pretty close. The hole on the tank is a bit smaller than 13/16...most likely close to the 16/33 it is supposed to be
I hope all of this helps and thanks for the quick reply. All that lays between me getting this out of my shop and to use after 4 years is this little bit. It seems like the new valve and bushing should have worked. It went in with a resounding thump and looked like it sealed better than the triton seal.
Cheap and nsty big fix is to get some glue lined heat shrink tubing.
Shrink it over the spiggot that goes inside the bush.
Apply liberal quantities of rubber grease and push in.
The .002" diameter increase should keep it in nice & tight.
The bushing which goes in the bottom of the tank is still available through Oregon or Stens. I’ll try to remember to get you part numbers when I go into the shop. The valve might be available through Oregon or Stens, but I’m not sure. Will check on that also, but it’s a very busy week, so have patience.
I appreciate all of the replies...to have this happen just as we get to the end of the project is frustrating...especially something so simple...I haven't let it drip gas and ended it all with a road flare yet so patience isn't an issue........not that I haven't been tempted.
I discovered that we still have a Wheel Horse dealer near us that still carries a lot of the correct parts for these older mowers and was able to get the correct grommet and the correct valve. It turns out that there was a hairline crack that ran along the seam so it was difficult to see. It became apparent when I sanded the area around the hole with a fine sandpaper. The mechanic at the Wheel Horse dealership sealed the crack with JB Weld. He said he has had some success doing this on other tanks but it's not guaranteed which I understand...It's worth a try...if it works then great...if not I guess I am no worse off. I also found another tank through a forum for $25 and plan to buy 1 even if this works...It may hold forever or it may hold through 1 cutting...always good to have a backup just in case.
I appreciate the replies and if anyone knows of a better priced tank, please let me know.
JB Weld is not really a good fix.
Plastic welds, yes a real genuine weld with nothing more than a heat gun or hair drier.
Home mechanics can be forgiven for using JB but a shop should be doing it properly if they are charging people money for it.
Unfortunately you will never ever be able to clean the JB weld off good enough to make the weld work.
With thermo plastics ( the ones that get softer when hot ) the ends of the molecules will always joint to others when activated.
You activate them by adding heat,
However they can only do this if the surfaces are absolutely clean and by prefference smooth ( prevents air getting trapped )
So you just heat it up till glassy looking then gently squeeze the crack with a hot stainless steel spatula.
You then let it cool down to stone cold .
After that you can put a patch over it but it must be the same family of plastics.
Somewhere on the tank will be a circle, square or triangle with a number in it.
You will see the same symbol on most plastic parts so you just match up the symboles and you have a patch.
Most fuel tanks are HDPE and funny enough milk bottles here are made from the same stuff.
This is really good cause with all of the curves & flats you can always find a good shape match.
Heat the tank till just glassy then hold the patch back a bit in the hot airflow till it goes glassy and bring the pair of them together as if you were applying a decal smoothing as you go to prevent trapping air under the patch.
The other method requires a special heating tool a bit similar to a soldering iron.
Lots of videos on U-tube but the ones put up by manufacturers & tool suppliers are what you should watch.
Eastwoods do a great kit and have good how to videos that are factually correct.
Where as 1/2 the shaved moron monkeys with egos 100 times their IQ will happlly tell you that everything can be fixed with the left over ends of zip ties ( PVC ) which of course is wrong and remember you are playing with a fuel tank, boom boom.
I appreciate the info...I guess I will go ahead and order the other tank. It seems to be a decent deal. For now I will just shape up the jb weld and hope it doesn't leak long enough to start it. I just want to make sure it ewill run.
.....not that I haven't been tempted.