plastic water tank and exhaust

[daveo]

i was given a poly water tank a few months ago and have only just got round to fitting it to the underside of my ute tray. to get it in i had to remove the rear half of the exhaust (dont think the neighbours appreciated me moving my ute with no muffler on), got it back in fine but the tank is approx 50mm from the exhaust. is this too close? if so would some sort of heat shield be enough to stop my tank melting? dont know what type of plastic the tank is made of. how hot does the last 1' of the exhaust get? ive never noticed (nor had the need).

also, on the other side the tank is about 2mm from the rigid brake line to the load proportioning valve on the chassis rail (see pics), should i be worried?

[toughnut]

I had the same thing with my water tank on my old tray. You can get some stick on heat shield like you see on the underside of some cars where the catalytic converter is. Its silver on the outside and its like bitumen on the sticky side. Don't know what its called though. Even with this there will still be some heat transfer into the water but your tank will be safe.

[-Richo-]

chop your exhaust just after your cab about 200mm past the cab i think, its legal, just need a muffler in there somewhere.

[SiKiD_01]

if you're handy, get hold of some 1.5mm or 2mm aluminium checker plate, and bend up a heat shield. if you have enough room, allow for 5-10mm gap between the checker plate and the tank. this lets air circulate and dessapate heat. i had a mate with a 75 series cruiser trayback that used this method. worked well.

i dont think the exhaust will emit too much heat, but be wary on long drives, or pro-longed stationary idling.

or if theres room between the tank and the tray, make up some blocks and space the water tank up.

with the brake lines, as long as the tank is secure, and does not move at all, it should be ok.

[toughnut]

Stainless steel is much better than alloy cause heat passes through alloy quite well. That's why there are alloy radiators etc. Stainless steel reflects heat.

[Patroler]

also the chances of melting the tank will be much reduced if you keep (some) water in it, doesn't need to be full, maybe 20-30 litres or so, that way if the plastic gets hot it will transfer the heat to the water and need to heat up the water before it can melt.

[phippsy]

Would it work to wrap that heat shield silvery tape around the exhaust where it goes near the tank??

[daveo]

cheers guys thanks for the replies.

i cant space the tank up at all, its bolting directly to the underside of the tray. will look into that heat sheild stuff that toughnut mentioned or else get some stainless and bootie fab something. its a dualcab ute soo choping the exhaust isnt really an option cause the end of the muffler is level with the back of the cab and id have to get a new one made up.

[daveo]

went to repco this arvo and all they had in the way of heat sheild stuff was some exhaust manifold stuff. how will this hold up to water/mud? it will prob be crap soo i think ill try and get some stainless anyway. any other suggestions?

[mickyd555]

the stainless is the way to go, shouldnt cost more than about $30-40 from what i can gather you'll need. and it will do the job quite well.......

[toughnut]

I think you'll find that it will be OK with the gap that is there. Mine only melted cause it was hitting the exhaust. The manifold tape will do OK cause it is up out of the way as long as you put in on tight and fix it at both ends with a hose clamp.