Exhaust hose temperature specifications

[Alii]

To cut to the bottom line -- what is the minimum acceptable top temperature rating for hose to be used for a wet diesel exhaust system?

Last we prettied up our 4JH2E with new hoses, 5 years ago in Australia, the yard recommended and we accepted "oil suction hose" by an unknown manufacturer. It seems to have held up well for the last 5 years / 3000 engine hours, in fact looks nearly new and remains flexible. We are now in Malaysia, again replacing all hoses, and looking at specs a bit more closely. And have not been able to find any true "marine exhaust hose" here locally.

Unigawa oil suction hose is manufactured here in Malaysia and when other (Aussie) cruisers in the yard ordered it as exhaust hose, we jumped on board. Research into generic hose of this type showed it should be good up to 100C/210F. After the hose arrived and I could see exactly what I had bought, I looked up the specs and saw that the hose was advertised as good up to 70C / 158F max. Called the factory to make sure the web site was correct, and they curtly said "yep, just 70C."

Next parts run to Singapore we visited a shop where we were told we could get good exhaust hose by the Steyr distributor --long story short, the store told us that their Alfagomma hose is good up to 100C but I have not been able to verify this (no written specs, nothing stamped on the hose).

The only time we've had problems with exhaust hose was with "official" Trident marine hose -- a bubble developed just before the waterlock. So I don't know that simply spending more money means more safety.

[GordMay]

SAE Specification J1527 USCG Type A, Class 2, Style R2 Exhaust Hose has a rated Temperature Range of -25˚F to +212˚F (-30˚C to +100˚C)

ISO Specification 13363 Class A, Type 2 Specifies a Working Temperature of-22°F to +248°F.

[NahanniV]

The spec you should be looking for is SAE J2006.

It should be printed on the hose.

The one Gord quoted is for fuel.

Cheers,
JM.

[GordMay]

Originally Posted by NahanniV

The spec you should be looking for is SAE J2006.

Thanks for the correction, JM.

American Boat and Yacht Council Standards call for hose that meets the requirements of SAE J2006 (or UL 1129) from the connection at the exhaust manifold to the overboard discharge fitting.

Hoses designated SAE J2006-R1 are "soft-wall hoses" (without wire reinforcement); those designated SAEJ2006-R2 have wire reinforcement.

It appears* that the minimum temperature ranges specified in SAEJ2006 range from -20°F to +200°F continuous, (+250°F intermittent).
The standard also requires resistance to exhaust fumes, ozone, mild chemicals, antifreeze, and salt water.

*I wads unable to access the actual SAE specifications.

Trident Rubber, for instance, produces three grades of SAEJ2006 compliant hose:
The standard rubber hose will tolerate continuous temperatures of 2500F; the blue silicone hose is good to 3500F;
while the top of the line red silicone hose will withstand temperatures to 5000F.

[a64pilot]

I don't know about specifications, but you can get hose made for live steam that will handle quite high temperatures if you can't find the correct hose.

[a64pilot]

Originally Posted by GordMay

The standard rubber hose will tolerate continuous temperatures of 2500F; the blue silicone hose is good to 3500F;
while the top of the line red silicone hose will withstand temperatures to 5000F.

Are these numbers a little high?

[model 10]

Originally Posted by a64pilot

Are these numbers a little high?

I think someone added a 0. Red silicone hose cannot handle 500 deg. I turns to back into sand around 2000.

[GordMay]

Originally Posted by a64pilot

Are these numbers a little high?

They’re what Trident specifies for their products
➥ Wet Exhaust Archives | Trident

OOPS (again), as Guy notes (then JM), the superscript didn't take, turning the degree symbol into a zero.

[NahanniV]

Originally Posted by GordMay

They’re what Trident specifies for their products
➥ Wet Exhaust Archives | Trident

Gord,

The numbers you gave are 10 times too high.

Maybe the degree symbol turned into an extra zero.

Cheers,
JM.

[Pierre]

Just visit this site for detailed description of exhaust hoses, specs and clamps

New-Line Hose and Fittings

this is not to promote the make but for specs.

Regards, Pierre

[Alii]

Thank you to everyone for the replies. It's tough to maintain a boat to American standards on this side of the globe, even in Australia where boat owners and yards rely on the 70C oil suction hose.

In Singapore I had ordered this Sunflex hose rated to 100C: OSD150 Oil Suction & Discharge Hose 150 PSI

but I may have been a bait-and-switch victim. The shop told me they were out of that brand, but had an identical hose from the same factory to provide. At least according to the web site, however, that hose is rated only to 80C.

Trident, Gates and Shieldsflex are not available here unless I ship in myself from the USA. I will continue my quest for Sunflex or Trelleborg, and if that fails I'll pursue the idea of quality steam hose.