Hose/Rubber Replacement Costs

It depends on if E-SLA or S-SLA.  Experimental can use automotive heater hose - I used High Performance Silicone heater hoses.  If S-LSA contact Lockwood or LEAF and tell them you are doing 5-year rubber replacement.  You might want to visit bank first and take out a loan... ?

My aircraft is an Australian experimental so I can use whatever I wish, however I try for hose that has published specifications, like Gates products (available through my local REPCO automotive store).

It can be hard to find the correct ID on some hoses - don't compromise buy Rotax if you cant source locally..

Don't use hose that is not recommended for that purpose eg coolant hose should never be used for oil/fuel.

Be very careful about bend radiuses. For coolant hoses you may be able to find a preformed (bent) automotive hose that can be cut down for use in your application removing the need to bend the hose. Oil hose can collapse, restricting flow,  if minimum bend radiuses are not observed.

Replace the hose for its full length . Do not cut & join at the firewall. This practise may save a few dollars & time but does not replace the rubber further back in the aircraft and introduces a potential failure point at the join.

There is one pre bent/formed coolant hose , on the top of the engine, that in most applications is best purchased from Rotax.

Cut your hose with a purpose made cutter, to reduce fraying and potential "rubber" contamination of the system.

Where possible, cut your hose to the maximum length so as to fit all the way onto he spigot.

Use quality hose clamps with 360 degree even pressure and no sharp edges.

Personally I don't like silicon hose - its heavy, doesn't usually have specifications, may lead the installer to extend life beyond the 5 year service interval and is not cost effective.

Here is thread from RV-12 VAF forum for 5-Year Rubber Replacement Alternatives....  https://vansairforce.net/community/showthread.php?t=186607&highlight=coolant+hoses&page=3

I'm PiperJ3 with posts starting on Pg. 3

One thing to check before purchasing the oil hose is if the aircraft has metric or AN-8 oil hose fittings. Rotax will ship the engine and accessories with either fitting type as per the customer request.  Check all fittings at the engine, oil tank and oil cooler.  I've seen aircraft in the USA with both metric and AN-8 fittings. The hose sizes for these two different fittings are very close, but if the improper hose is used it will be a poor fit. I have seen the metric fittings (improperly) used with 1/2" hose, which is just a bit loose and tends to leak at the hose clamp. 

Identifying the Fittings

AN-8 fittings have the socket (concave) on the hose end and the cone (convex) on the oil tank or engine. The hose fitting goes “over” the oil tank fitting. The AN-8 fitting threads are 3/4” across.  The proper hose is 1/2” (12.5mm) ID.

Metric fittings have the cone (convex) on the hose end and the socket (concave) on the oil tank or engine. The hose fitting goes “into” to oil tank fitting. The metric fittings are 18mm (.71”) across. The proper hose is 12mm ID.

James Stricker wrote:

Here is thread from RV-12 VAF forum for 5-Year Rubber Replacement Alternatives....  https://vansairforce.net/community/showthread.php?t=186607&highlight=coolant+hoses&page=3

I'm PiperJ3 with posts starting on Pg. 3

Don't know anything about "cold leak" but then I don't use silicon hoses on my Rotax, for the reasons mentioned above.

I cant see the point of silicon in this application - cost more for, in my view, zero benefit and may lead the pilot/maintainer to extend/skip the 5 year rubber replacement instruction, which has benefits beyond just replacing hoses.