Hydrohoist tank leak (fiberglass holes)
 

Hello everyone

I have read several threads to find a solution to my hydrohoist leak puzzle but to noavail... I have replaced all air parts, including valves hoses but then realized that the leaks were coming from the fiberglass itself. I removed the tanks from lift and are sitting in my shop after giving them a good cleaning. I plan on using the air compressor to pressurize the tanks but not sure what to do the outflow hole at the bottom. Does anyone know of a good way to plug the hole which can sustain the air pressure? I'm really looking for a working solution that someone has tried before. Your help is appreciated. thanks.

what size hole?
if it's round these come in many sizes http://www.simplyplumbing.com/32047-...UnkaAmut8P8HAQ

I know on my 8K lift you can easily stick your fist up thru them with plenty of room to spare. .

If they are that big maybe let the air out of a small smooth fender or ball, stick it in the hole and air it back up

I made up some tapered nylon plugs years ago , they were around 4 " on a 6500 # 3 tube hydro hoist , still have one in the garage somewhere. They are drilled so you run big zip ties thru and cinch them up around the tube . A ball or small football and a hand pump would work better to seal but I wouldn't be putting much pressure to those tanks

Hydrohoist makes a tank plug you may be able to adapt something on your own .
Keep in mind the tanks Max out at 5 psi in air so carfull when testing them

What is the age on the tanks?

I would plug top hole with threaded fitting role it over and fill it with water safer then air. To much air could blow out the tube

This sound like the best way

The expansion plugs shown will work. Just get the right size

My hoist was slowly leaking for a few months. Finally dunked it just under water and waited for a few minutes while water calmed down. Noticed very small bubbles coming from holes on end of one of the tubes. Same end that sticks out where Fukin fishing men throw towards. 2 very small holes about the size of a lure hook- magine that.
Used some fiberglass repair that comes in 2 tubes injector type and mixes as it comes out. Looks ugly buy No leak.

Thank you all for the quick response. I went ahead and purchased the 4" PIPE PLUG WITH WING NUT. My next task is to identify the leaks then patch them with fiberglass. Any recommendation on the type of fiberglass to use for the tanks? Also, would the 3M 5200 work on tiny holes. I've never worked with the 5200 but heard good things about it. Thanks again!

Only use epoxy resin. We used West system on ours

Mark

Hi cmattj,

I have finished the fiberglass patching work and pressure tested the tank at 2-3 psi. so far, I haven't seen any leaks. I wanted to go more than 3 psi but don't want to push it too much. you stated 5 psi max, the vendor stated 1-3. Before I assemble the lift and haul it back to the water, is there any other way of testing for leaks. I was thinking about filling the tank with water and let it set but not sure if that's a good idea giving the massive water weight against the fiberglass and the support. Any suggestion?

I also plan on sanding and repainting the whole fiberglass using the Rust-Oleum Marine Bottom boat - (link) - Any recommendation on paint is appreciated. Thanks.

Lol, I remember the tinbender in our old shop telling me about testing the first gas tank he built at 7 to 10 psi, said it turned into a balloon rather quickly! Think about all the force in pounds per square inch. :eek:

It sounds like your confident in your findings.. I'm not sure how you located the leak.
Don't fill it water although that's a good idea on valve checks for cylinder heads.
Spray the tank down in small sections with soapy water while keeping the psi at 3 psi and just go over the ends at the nipples on front and plastic top center and facing. ( as mentioned a pin hole from a fisherman rattle trap can leave a pin hole above the water line)
Spray the top side seams slowly and you'll be good to go.
Painting is a final commitment to maintain and I would fear it's not needed.. lightly pressure wash the tank but keep in mind you can disrupt the fiberglass if cleaned with too much pressure as you'll notice the glass is usually exposed on end caps and along the sides..
Final note ....once installed and raised clamp off the hoses to that tank side close to the control box to insure the leak is repaired.. tubes change once clamped and in work so check the with the same technique you've done..
Best of luck .. sounds like you got it!!