how to remove the fuel sending unit from a bladder

I am trying to remove the sender from a fuel bladder in a 2003 cav. I'am trying to not harm the rubber it's self. in my delusional mind I hope I can clean the old foam out and put new in. the sealer is very strong.
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I am trying to save the tanks without removing them. on this cav I think you have to take off the front suspension and pull the tank forward.
bladders aren't leaking but the foam is slowing the fuel flow.
if this doesn't work, I will be ordering new tanks
 
I am trying to remove the sender from a fuel bladder in a 2003 cav. I'am trying to not harm the rubber it's self. in my delusional mind I hope I can clean the old foam out and put new in. the sealer is very strong.
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on my bladders the sending unit can be pulled straight out after removing the wires and nuts/bolts on top of the unit. Your photograph indicates that this is the same in your case.... In any case, I'd renew the entire bladder (keeping the sending units and other hardware). It costs some money but it's quite some work to pull the old bladders anyway...
 
on my bladders the sending unit can be pulled straight out after removing the wires and nuts/bolts on top of the unit. Your photograph indicates that this is the same in your case.... In any case, I'd renew the entire bladder (keeping the sending units and other hardware). It costs some money but it's quite some work to pull the old bladders anyway...
I don't think it is possible to replace the bladder only. there is only a 2 1/2 inch hole to work through.
I am thinking if I could find an explosion proof vacuum I could suck the old foam out. summit sells the new foam.
if it works, great. if not, time for new tanks.
anyone know where I can get a explosion proof vacuum or another way to clean out the tank.
 

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2 things come to my mind: I have used bladders for track-only cars for ~ 20 years old without any fuel-feed problems. Have you checked the fuel filter(s) and the pickup lines? Once I found that issue on a car I had just purchased. The bladder got renewed anyway since I needed FIA approval.
2. Usually the bladder is stuffed into a solid (aluminium or steel) tank - the latter may be part of the body, as on my RCR40. On all my cars I can open this tank one way or another to remove the bladder for service/renewal.
 
2 things come to my mind: I have used bladders for track-only cars for ~ 20 years old without any fuel-feed problems. Have you checked the fuel filter(s) and the pickup lines? Once I found that issue on a car I had just purchased. The bladder got renewed anyway since I needed FIA approval.
2. Usually the bladder is stuffed into a solid (aluminium or steel) tank - the latter may be part of the body, as on my RCR40. On all my cars I can open this tank one way or another to remove the bladder for service/renewal.
cav gt 40's tanks are way different. here is what I got when I pumped out 4 gallons and stopped up my fuel transfer pump
 

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ok, seems you got some low-quality foam here. Your best bet is to get new high-quality custom bladders (bag tanks) (FuelSafe, ATL, ...). On a GT40 the sills can serve as the hard-shell container and all you need is the bladders - as on my car. Of course, one can use an additional hard case (around the bladder) which slides into the sills as a unit.
 
ok, seems you got some low-quality foam here. Your best bet is to get new high-quality custom bladders (bag tanks) (FuelSafe, ATL, ...). On a GT40 the sills can serve as the hard-shell container and all you need is the bladders - as on my car. Of course, one can use an additional hard case (around the bladder) which slides into the sills as a unit.
factory cav tanks from 2003. the good news is the other tank filter is super clean.
I have sucked up as much of the old foam as I can get out of the tank. next I will use a extra pump and filter, circulate new fuel through this rigged system until the tank is somewhat clean, then put every thing back as it was, then keep checking the filters. I know this wont be permanent fix but it should get me through the summer. thanks for your help.
 
have you been able to pull the sender? You may get fuel slushing around upon acceleration if you don't add new foam. Anyway, your plan should get you through the summer - best of luck!

Maybe a CAV owner can give more specific advice???
 

Ian Clark

Supporter
Hi Steve,

Here's a couple of pictures of the early CAV GT fuel cell taken in my shop today.

We don't have a CAV GT in the shop right now however we are using the bladder tank for reference to make two sets of aluminum fuel tanks for customer cars that have been driven since 2005.

The fuel senders can be no fun to remove with the cells in the car but the foam blocks ( or crumbles ) won't come out with the cells in the car.
The access panels on the top are used to pack the foam blocks in the tanks, check the fuel pickups and returns as well.

There are simple ways to drop out the front suspension (without loosing the alignment) if you decide to pull the tanks. Best advise is to replace the tanks with as like (or alloy). The bladders were never designed to live with todays fuels but there is more stable foam available.

Cheers
Ian
 

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Neil

Supporter
Hi Steve,

Here's a couple of pictures of the early CAV GT fuel cell taken in my shop today.

We don't have a CAV GT in the shop right now however we are using the bladder tank for reference to make two sets of aluminum fuel tanks for customer cars that have been driven since 2005.

The fuel senders can be no fun to remove with the cells in the car but the foam blocks ( or crumbles ) won't come out with the cells in the car.
The access panels on the top are used to pack the foam blocks in the tanks, check the fuel pickups and returns as well.

There are simple ways to drop out the front suspension (without loosing the alignment) if you decide to pull the tanks. Best advise is to replace the tanks with as like (or alloy). The bladders were never designed to live with todays fuels but there is more stable foam available.

Cheers
Ian
After the experience of removing a fuel cell bladder from a McLaren M8C back in the Can- Am days, I am convinced that it was a job for a gynecologist.
 
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