Fuel smell on 98 Glastron GS 185

[familyguy]

I have a 19 gal. Moeller Marine crosslink polyethylene tank and have noticed a strong fuel smell everytime I take the cover off or put my nose in a storage hold or the engine compartment even when the cover has been off for some time. Sometimes when I'm out on the water I will smell it fairly powerfully, too. I know fuel vapors sink. However, if I've had the cover off for some time shouldn't the vapors dissipate?

Looking at a moeller's marine gas tank weblink I read something about "permeation" and that this is normal. Should I smell gas around the tank because the gas has saturated the tank wall material and this is normal? The boat does a engine compartment blower.

What I've done so far:
1) Exposed the tank
2) Plugged the fuel pump supply hose, plugged the fuel fill hose, and applied vacum pressure to the vent line. I'm unable to register any vacum pressure.
3) Then put positive pressure with my lungs into the vent hose. Was able to see the tank start to bulge. Took my mouth away and audibly heard pressured airflow leave said hose.

I don't have a positive pressure gauge that reads small increments of psi. I know I can get one fairly cheap, but how do I apply a small amount of positive pressure to the system once it is attached (without blowing into the system with my mouth), since I don't want to exceed 3 psi? I'm trying to pressure test the boat side of the fuel system without having to drain the tank and pull it.

 

[180shabah]

Re: Fuel smell on 98 Glastron GS 185

What condition are the fuel hoses in? After 11 years you could be due for new ones.

 

[grego]

Re: Fuel smell on 98 Glastron GS 185

Any RAW! fuel smell should be addressed with caution! Even the fans emit a small spark. as far as saturation? I don't know. I! would take to shop,some times "You use a professional"!!

 

[Nandy]

Re: Fuel smell on 98 Glastron GS 185

2) Plugged the fuel pump supply hose, plugged the fuel fill hose, and applied vacum pressure to the vent line. I'm unable to register any vacum pressure.

If I recall right a neighbor of one of this forum member blew up his vacuum that way when the gasoline gasses reached the vacuum motor. Please be careful.

I'm sorry but I don't have anything to add as far as what to do to solve your problem. I agree that any gas smell needs to be addressed.

Good luck!

 

[5150abf]

Re: Fuel smell on 98 Glastron GS 185

If you smell a strong gas smell it is a leak and it isn't simply coming through the walls of the tank.

I would certainly not run this boat again till I found the leak and make sure you have ready access to good fire extinguisher.

And yes I would drain the tank before you pressure test.

Having just delt with a gas fire I was reminded how easily it is ignited and how quickly it burns and that was in my garage with a cement floor not inside a fiberglass boat, this is a VERY serious situation you have here.

Changing a fuel pump in a car and the tank went up, had an extinguisher right there and it was out in seconds with no damage but a very valuable lesson.

I would disconnect the fill hose and fold it over on itself then tape it to seal that one and use the supply hose to apply the pressure then spray the whole thing down with soapy water till you find the leak.

We test our tanks at work at quite alot more than 3 psi, I would think your tank should easily hold 5 and that will make it easier to find your leak.

A big extinguisher at WalMart is less than $40, I imagine your boat is worth more than that so I would start there.

 

[familyguy]

Re: Fuel smell on 98 Glastron GS 185

Hey guys, thanks for your input. I haven't done anything else since that day, since it has been raining and my boat is in the side yard (covered of course).

Incredibly, the hoses look great. The whole boat looks very well maintained actually. I'm the second owner and the first guy kept it garaged and didn't put more than 100 hours on it! Regardless, I'll still replace the fuel pump supply hose. The fill hose is very rigid, about 2" outside diameter, so I don't think I can fold that thing. Either way I'll pull the hoses off the fill and vent fittings on the tank and plug the ports before I pressure test using the pump supply hose as you recommended.

I will definitely drain the tank. Skimming the forum I saw some good pictures of how to rig a positive pressure gauge with a bike pump and combination gauge (used for measuring positive and negative pressure). I'll also call the boat dealer who originally sold the boat and ask him about the permeation thing.

When I applied vacum pressure it was with a handheld gauge such as one used for bleeding brakes. Therefore, no electricity required. I also have an extinguisher at the ready. The batteries have been pulled out of the boat.

 

[familyguy]

Re: Fuel smell on 98 Glastron GS 185

Since then I have:
1) Drained the tank using an automotive Mitivac handheld gauge (used for bleeding brakes) to create the vacum, clear tubing purchased from home depot in plumbing section 10', 3/8" diameter, and a portable 5 gal. tank. Don't use the fuel pump supply port fitting on the boat tank since this has an antisiphon valve. You will keep losing vacum. Use the vent tube fitting on the tank and feed at least 2 1/2' of clear tubing down it.

2) Pressure tested the tank using a combination gauge purchased at Kragen T-fitted onto some tubing (you need various sizes which you can get at any auto store) with one end of the tubing fitted to a bicycle tube stem (cut off the bike tube at the base of the stem). This was used for applying pressure. The other end of tubing attached to vent fitting on tank. The fill port fitting on the tank is 1 1/2" in diameter and isn't that easily plugged. I used duct tape, then the otherwise useless bicycle tube cut into a 5"x5" square placed over duct tape and held in place by a 1 1/2" circular screw clamp (same one used to hold gasoline fill tube onto fitting). I plugged the fuel pump supply port fitting on the tank with a hose and placed a small rubber stopper in the open end. Don't use this port for applying pressure (use vent fitting) since this antisiphon valve also acts as a one way valve not allowing pressure to be forced into the tank. I applied pressure with a motorized air pump attached to a fitting used for filling car tires. BE VERY CAREFUL and make sure the combination gauge you have reads psi in single digit increments since you DON'T WANT TO EXCEED 3 PSI.

3)After all that I sprayed the entire tank down in soapy water and discovered my tank is fine, no leaks. I closely inspected the fill fitting on the back of the boat that the fill tube and vent tube attach to. The engine compartment fill, vent, and fuel pump supply hoses are all in good shape without any noticable cracking. So the only thing I can attribute the smell to is the "permeation" thing and maybe gasoline vapors wafting up the two-barrel carb and out of the spark arrestor.