Leaking fuel tanks

NPKenny · Dec 22, 2019

I have a few saws with leaking fuel tanks at the seam (350/346, 288, 660). I have considered it just a slight inconvenience and know to drain the tanks immediately after use.

I started looking at the purpose of tank vents for run ability issues on a few other saws and my understanding of tank pressure has complety changed; the fuel tank needs to hold pressure to feed fuel to the carb and a leaking tank vent needs to be replaced immediately.

With this understanding, it seems that a leaking fuel tank can cause running issues as well. Please discuss.

huskyboy · Dec 22, 2019

It won’t cause running issues. The carb diaphragm and impulse line is the fuel pump that feeds fuel to the saw. If those two don’t work, the saw won’t run. The leaking tanks are an annoyance and a hazard though.

Basher · Dec 22, 2019

No tank pressure required for an all position carb to operate correctly, as already mentioned these carbs have a fuel pump diaphragm.

NPKenny · Dec 22, 2019

Why the 2-5 psi requirement on pressure test according to the procedure below? Maybe pressure to the carb isn’t the issue.

Maybe the other part of my question is what are the operating symptoms if the vent is faulty, holding no pressure?

Item #11 below.

huskyboy · Dec 23, 2019

NPKenny said:
Why the 2-5 psi requirement on pressure test according to the procedure below? Maybe pressure to the carb isn’t the issue.

Maybe the other part of my question is what are the operating symptoms if the vent is faulty, holding no pressure?

Item #11 below.

View attachment 214257

Because the epa doesn’t want fumes getting out or gas seeping out under pressure into the environment. Look at the tank vents on newer and older saws. Older saws they were just sintered plugs that weeped fuel sometimes. Newer saws they are more restrictive and build pressure. It’s because of the epa.

alleyyooper · Dec 23, 2019

A leaking tank seam can be fixed very easy just takes time to do it right.

I had a leaking one on a Husky 455 rancher, dealer wanted 170.00 to fix it (new tank). I declind the cost and brought it home.

Friend is a hydro plane boat nut, told me a easy fix so we took it to his shop to prep.
A marine fuel safe tank seal was put in once we had fully clean the tank and soaked it. On the out side it was scuffed and a layer of locktie 2 part epoxie was applied. that was 5 years ago and is still working and not leaking.

Cost to fix was less than $15.00.

Al

andyshine77 · Dec 23, 2019

The tanks need the pressure in hotter months to keep the fuel from evaporating and in some cases boiling, this helps prevent vapor lock. It's not all about the EPA.

Lightning Performance · Dec 23, 2019

It's better to just fix it. You to experience a flaming saw.

Panel bond is my new go to fuel tank and plastic fix all in one. Zero issues. Strong, fuel resistant and flows well.

NPKenny · Dec 23, 2019

Lightning Performance said:
Panel bond is my new go to fuel tank and plastic fix all in one. Zero issues. Strong, fuel resistant and flows well.

Something like this?

3m Panel Bonding Agent

Lightning Performance · Dec 23, 2019

NPKenny said:
Something like this?

3m Panel Bonding Agent

Eggzackly
Don't use the tip. Mix it like JB. Stuff is amazing.

Leaking fuel tanks

NPKenny

Super OPE Member

huskyboy

Sorta a husqvarna guy...

Basher

Pinnacle OPE Member

NPKenny

Super OPE Member

huskyboy

Sorta a husqvarna guy...

alleyyooper

Pinnacle OPE Member

andyshine77

Pinnacle OPE Member

Lightning Performance

Here For The Long Haul!

NPKenny

Super OPE Member

Lightning Performance

Here For The Long Haul!

Similar threads