Stainless Coolant "Hoses"

[aussierob]

Hi Everyone,

Just wondering if anyone has any thoughts on using stainless pipe for fresh water / coolant circulation?

I'm changing from Log-style to center risers on my 5.7L engines, so can't re-use many of my hoses (they're not in the best condition either, so i probably wouldn't even if i could).
My heat exchanger already has some stainless pipes. It got me thinking - why not fabricate stainless pipes for everything?
Would be fairly easy with some mandrel bends and straight pipe, and would be "coupled" using standard exhaust tubing (which would also absorb any vibrations etc).

It would take a little more work than standard hoses (my heat exchanger was mounted non-standard so already have to find non-standard hoses), but not alot more - and would be quite robust.
Also considering only using the flexible exhaust tubing - that would make life VERY easy too.

I can see why it wouldn't be a good idea running raw water... but for fresh water circulation?
Would enjoy input / thoughts on the topic.

Thanks,
Rob

[mike ohlstein]

Unless you use schedule 40 stainless, you're going to have a tough time tightening the hose clamps enough without crushing the pipe. Remember, hose is clamped to a heavy internal (BARBED) fitting. You're going to try to clamp to the stainless. Schedule 10 pipe may crush (or worse, come apart). Also keep in mind that hose is measured in ID while pipe is measured in OD. Two inch pipe won't flow as much coolant as 2" hose. You would have to go with 2.5" pipe to get 2" ID. I presume that you would also want to figure out a way to 'barb' the pipe.

It'll probably look cool. May not be to code.....

[mike ohlstein]

One more thing, you MUST use hose that is reinforced with wire on the cooling system...... so potentially not so flexible. (I'm assuming that you were suggesting using flex hose like that cool looking silicon stuff on the cooling system) Unlike the fully pressurized exhaust system, the cooling system is pressurized from the water pump outlet about half way around, but is suction on the water pump inlet side. Non-wire hose will collapse. Maybe not right away, but eventually and with some certainty.

[Tommy]

Rob, now you know why we call Mike "The Professor"; he has been a great source of help for all of us over the years. Good luck with your project.

[aussierob]

One more thing, you MUST use hose that is reinforced with wire on the cooling system...... so potentially not so flexible. (I'm assuming that you were suggesting using flex hose like that cool looking silicon stuff on the cooling system) Unlike the fully pressurized exhaust system, the cooling system is pressurized from the water pump outlet about half way around, but is suction on the water pump inlet side. Non-wire hose will collapse. Maybe not right away, but eventually and with some certainty.

Thanks for the thoughts Mike - i agree, perhaps not up to code. Might run the idea past a shipwright / mechanic for feedback. I was really only considering the welds having to be really solid and pressure tested.
I can flange/roll the ends to create a barb, but you do raise a very valid point about internal / external diameters creating some challenges fitting everything together.
I guess the idea came from having existing stainless pipe.

I was referring to the wire-reinforced hose - my engines use that between the heat exchanger and risers on the raw water side, and it's rather versatile - so the idea was simply to use that everywhere if stainless wasn't a viable option. It would certainly be considered "up to code". There are no extraordinary bends that are required i don't think - but i'll assess when i have everything.

Thanks
Rob

[Tooeez]

Rob, I thought about center risers when I repowered my 28, and found I did not have enough clearance under the hatch for them. Because of the angle of the engines the further forward you go the closer to the hatch--that's why the heat exchanger is mounted on the aft end.

[aussierob]

Rob, I thought about center risers when I repowered my 28, and found I did not have enough clearance under the hatch for them. Because of the angle of the engines the further forward you go the closer to the hatch--that's why the heat exchanger is mounted on the aft end.

Tooeez,

I wasn't sold on the center rise change initially, but there are so many less physical parts to fail. Also, the old log manifolds and risers are horribly expensive over here - i could buy a whole set of center risers for less than the riser / spacer for a log style. My risers need replacing anyway, so i figured it would solve a host of problems down the line. I was planning to change the exhaust from the original copper one anyway, so it seemed like a sensible thing to do overall.

My heat exchangers were actually mounted on the fore bulkhead. I've seen various different configurations. But additional height would provide more options.

I do need to raise the hatches to accommodate i believe. Looking at changing to a one-piece hatch like Kevin has done. My current hatches have cut-outs from the reinforcements for the risers and flame arrestors - just doesn't seem like the best solution to me.

Rob

[Carl]

I can't answer to code or not...

You can always use tube instead of pipe for sizes.
Ends can be Rolled or Turned for clamping prior to mandrel bending.

Its been done and it works...but unless you have some real funky setup, hose can be quicker and neater.

With hose you don't have to deal with vibration and rattles if pipe touchs something solid.

Working around hot pipes is lousy, hose insulates the heat.

Longer pipe runs hanging on a hose stresses hose if not supported...working on motors a little bend, push or pull of a hose will get you in closer for a better reach...pipe not quiet as flexible and pulling and pushing on it to make your way in brings me back to it stresses the hose connections.

[White Bear]

Better is the enemy of good. Ofttimes when trying to improve on one component in a system unintended consequences arise. While in an ideal world it might be nice to have all stainless plumbing, in reality it brings with it a whole host of compatibility problems that can be avoided by the use of traditional materials. Since you're only plumbing the fresh water side of a cooling system and haven't cited any past problems, why reinvent the wheel.

[ford351c594]

Rob, I thought about center risers when I repowered my 28, and found I did not have enough clearance under the hatch for them. Because of the angle of the engines the further forward you go the closer to the hatch--that's why the heat exchanger is mounted on the aft end.

I just did this with my repower. had to raise the front section of floor about 2.5 inches. Then I just read the post on the one post hatch and was mad at myself for not doing that......