'75 Fuel Tank Bladder
Thread Starter
Heel & Toe
Joined: Oct 2007
Posts: 18
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'75 Fuel Tank Bladder
I just pulled the fuel tank out of my '75, to replace some leaky rubber lines, and noticed my tank has a rubber bladder. I was just curious, what was the purpose of the bladder? While I have the tank out, I'll sand the outside down and put a coat of paint on it - is there any preventative maintenance I should perform on the bladder, while I have the tank out? Thanks.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
The bladder was a safety feature, designed to keep the fuel in the tank in the event of an accident where the tank itself ruptured.
There are a lot of problems these bladders can cause. They deteriorate and fall away from the walls, collapsing, causing a loss in fuel capacity. They can also keep the fuel float from giving you an accurate fuel level reading. Sometimes fuel or water gets behind them, and rust holes develop causing leaks.
Mine was shot when I pulled my tank. I didn't want to fuss with buying a new one so I cut the nut ring off of the top of the bladder and put the tank back in without it since it was in great shape. I actually gained about a full gallon of capacity.
If yours is in good shape and it's holding it's form then re-use it. If it's bad, you can either replace it or go without it.
There are a lot of problems these bladders can cause. They deteriorate and fall away from the walls, collapsing, causing a loss in fuel capacity. They can also keep the fuel float from giving you an accurate fuel level reading. Sometimes fuel or water gets behind them, and rust holes develop causing leaks.
Mine was shot when I pulled my tank. I didn't want to fuss with buying a new one so I cut the nut ring off of the top of the bladder and put the tank back in without it since it was in great shape. I actually gained about a full gallon of capacity.
If yours is in good shape and it's holding it's form then re-use it. If it's bad, you can either replace it or go without it.
Le Mans Master
Joined: Jul 2000
Posts: 6,001
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From: Saginaw Michigan
I have never found any supplier that had the bladder available to purchase (not refering to eBay.) I had heard that no one wanted the liability associated with a bladder failure and potential fire.
I agree with all of the above bladder problems and old age. (Gee that might be talking about me personally.)
Jim
I agree with all of the above bladder problems and old age. (Gee that might be talking about me personally.)
Jim
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From: Massillon,Ohio USA
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Thread Starter
Heel & Toe
Joined: Oct 2007
Posts: 18
Likes: 3
The rubber on mine looks to be in great shape, and its still pressed up against the walls, so I guess I'll just make sure the vent is clear, and put it back. '74 and earlier didn't have the bladder, though? Maybe it was in response to some crash fires.
