Merlyn 11A Coolant Tubes

[Angus]

The coolant transfer tubes (top two chassis tubes) in my Merlyn 11A are nearing the end of their useful life...already had to weld one small hole.

During the summer break I'll be re-routing the coolant through aluminum tubes between the chassis and bodywork.

Does anyone have any experience fabricating these tubes on an old FF? The existing tubes are 1.25 inches in diameter, but I don't know what wall thickness people use or where to get the aluminum tubing.

Thanks in advance!

Angus

[Brian]

I would use 1.25" 16 gauge 6061-T6 tubing, as it's about the most commonly available. Here is a supplier in Dallas, but just look in the phone book for metal suppliers.

http://data.gointranet.com/cgi-bin/u...0werner&cl=525

Brian

[Roland V. Johnson]

Try Aircraft Spruce. They can ship 8' sections via UPS. If the upper frame rails are leaking, think about what would happen if you are hit in the side of the chasis. We had someone seriously injured when the tubes broke in a crash several years ago. The chasis is brazed together, and the tubes can be replaced by a competent welder.

[Frank C]

I agree on replacing the frame tubes for structural reasons! Do the coolant tubes need to be bent? I believe that the tubing you can get from Aircraft Spruce, etc., will be hard and must be annealed before bending. This is beyond the competence of some of us!
- Frank C

[TimH]

If the upper frame rails are leaking, think about what would happen if you are hit in the side of the chasis.

Yikes yes! Those structural elements were designed with no intention of lasting 30 years.

[Angus]

Thanks very much to all the information and suggestions.

I think I can do this with straight sections of tubing (I'll have to roll hose beads into them), but if I need bending/welding I know some people who fabricate for a living.

I'll check the upper chassis tubes after next weekends race...the car will be pulled apart to have the tubes under the engine/transmission replaced, they have suffered over the years.

Thanks!

Angus

[Angus]

I just received several lengths of 1-1/4" 16 gauge 6061-T6 tubing from my dear freinds at Aircraft Spruce and Speciality. The wall thickness seems "more than adequate", just curious as to how thin people have gone with their aluminum coolant tubes?

Thanks (again).

Angus

[stephen wilson]

I used .049 on my RF78. Carol Smith agrees, .049 if there are no bends, .063 if bent.