3/8 " coolant hose substitute

[oilboy123]

Seems Auto stores never seem to carry the smaller coolant hose. I was thinking rubber transmission hose would sub better than Fuel injection hose.

My thought is the trans fluid has higher temp resistance inside the hose vs fuel does not need much heat resistance other than the outside. Maybe it's a toss up? It's a F150 truck. Seems like the Fords I work on always use this small hose.

Which of these two would you use and why? Or would you search for the stuff made just for coolant use?

 

[Kuato]

My first thought is the the coolant hose has to resist not only pressure, but also suction. If the trans fluid hose isn't resistant to suction, then it will collapse.

 

[HTSS_TR]

I bought 3/8 " coolant hose by the foot at Kragen few months ago. They have these sizes: 3/8", 1/2" and 3/4" in a reel, you just cut it by the foot, minimum is 1 foot.

 

[oilboy123]

Well the store I went to was a Shucks, changed to O'Reilly. They should carry a coolant hose. Maybe I will try to order it?

 

[Rooy]

I've used fuel line in place of coolant hoses. This was 5/16" size. It's held up fine for a couple years now.

 

[onion]

3/8" fuel hose will work, but it'll become hard and brittle after a couple years.

Some autoparts stores will carry it- not the chain-discount stores like Autozone, but more shop-oriented parts stores like carquest, Napa, or independent places often have it. Also, heavy truck shops often stock the stuff- sometimes even in silicon.

Myself, I need to find some 5/16" coolant hose for my old Corsica. I've yet to find it anywhere. I've got by for years using fuel hose, but have to replace the stuff every couple years when it hardens.

 

[oilboy123]

What about power steering hoses for better hi temp life?

 

[mechtech2]

Fuel injection rated hose should be better than coolant rated hose.
Lots of tranny lines and coolant lines are repaired with this.

 

[joel95ex]

for small bypass hoses I have always used the fuel hose you buy by the foot. It holds up well to pressure, but the temp gets it after 2 or 3 yrs. it is fine unless you need a molded hose with a sharp bend and you can't loop it.

 

[oilboy123]

What about the fact that transmission hose is made for higher internal temps? vs fuel injection hose which the fuel is normally not at a high temp?

 

[dwendt44]

The pressure they are designed for may affect use.
F.I. hose has to withstand 40-50 lbs or so pressure.
Trans hoses don't have to hold that much pressure.
Heat V. Pressure.
Interesting trade off.

 

[ludey]

I would make sure it is a type of heater hose. I have a overflow hose going back to the radiator and tried fuel hose. My overflow hose is metric and is kind of hard to find. Bad mistake. My coolant darkened with remnants of the fuel hose. The fuel hose was decomposing inside out. Went to a local speed shop and got 3/8" heater hose from Gates. It is the one size close enough to the original overflow hose. They sold it by the foot. It worked out great and no more dark black coolant.

 

[AuthorEditor]

Being near the coast in Washington you should check out a large marine store (chandlery). They should stock coolant/heater hose in small sizes that you can buy by the foot.

 

[mechtech2]

dewndt -
Standard fuel line is only rated for 50 lbs [3/8].
But FUEL INJECTION HOSE is different and better. More like 180 lbs max rating.

Auto trannys produce get more than 50 lbs, BTW.

 

[oilboy123]

Well the pressure tolerance of the FI hose or the Trans hose should not be a factor in my mind. I'm worried about the compatibility of the heat and the temp tolerance.

 

[mechanicx]

I think you need a coolant type hose for longest service life because coolant hoses use a different rubber compound more resistant to hot coolant, I think EPDM typically, from fuel and transmission hoses.