How do you protect the hot water lines

[Snedly]

Sorry if this is old stuff but how do you all protect the rubber heater hose that's running under the car? I looked mine over pretty good and decided not to run the hose in the center tunnel like I thought I would because the exhaust is to close.

Thanks

[Fatmobile]

When I ran my fuel line under the Rabbit, I ran it inside some exhaust pipe.
5 feet with about an 80 degree bend on the end.

[Krank]

Fatmobile,
I've been contemplating the same thing. What sort of temp rise do you get? Have you had a problem with rattling? Are there any pit falls or down sides you can share?

[Fatmobile]

I don't have a temp gauge on the vegy line anymore so have no idea of the temp rise.
Downside would be something under the car can be banged up with rough terain or road debris.
Also isn't much room under there to play with.
No rattling.
I bolted the exhaust pipe to the body using old timing belt for strap. I didn't leave enough timing belt on the end and it frayed enough to let go of the pipe.... just as I was getting home and a day before the big trip to the energy fair.
Can't ask fo much more than having a small breakdown in your own driveway before a big trip. Could have been at a much worse time and place.... if it had waited a day.

[Krank]

What I was thinking of doing was running a few feet of stainless vegi line inside the actual exhaust, making sure I send it around a bend to force heated exhaust against the line.
Has anyone tried this? Is this too radical, or has it been tried and discarded already?

[seth]

i was thinking of doing the same thing. do you run the risk of fuel getting to hot, if so how do you prevent it. what is the min/max temp needed for svo?

[jkeiffer_gearhead]

I think fatmobile meant that he ran his HWH setup inside of an exhaust pip to use it as protection, but not run exhaust through it

[Krank]

Yeah, I figured that out very shortly after the post I made. This doesn't turn off my curiousity, though. Perhaps I need to sample temperatures on the exhaust pipe at various different location under different conditions. I suspect this would be an effective / efficient way of harnessing the waste heat!

[jkeiffer_gearhead]

I have contimplated the idea as well, I think that the best bet depending upon temperatures is to use the exhaust to heat the tank and still use cooling lines to and from the tank to keep the temperature consistent.

[vwtyp133]

A further idea & question about heating the veggie tank.

Mid-to-late 70s GM vehicles had the flatish & oval-ish catalytic convertors that were filled with beads. Those for V8s were usually 2.5" diameter in/out, and were issued one per car, at least with the common Chevy small block vehicles I've worked on.

Would one of those, with the catalyst beads emptied out (they actually even have a plug for this!), and strapped to the bottom of the WVO tank, be a good heat source if the VW diesel's exhaust ran through the hollow shell? If so, could a TD possibly use it as sufficient resonator that one might eliminate using a muffler in the system?

At least in Kaleefonia, the boneyards say they can't legally sell used cats, but they are yanked and discarded by the guys who run the demo derby favorite cars: gutted '72-'76 B-O-P-C big station wagons, so some availability does exist.

J.R.
SoCal

[VW cat]

I remember that converter, I had one on my '75 Camaro for a short time. Sooner or later someone is going to come up with a reliable heat exchanger control. It could be as crude as the old diverter valve using the bimetal spring. Remember the one used on the Chev 283's that applied back pressure on one exhaust manifold to help preheat the carb base?

[vwtyp133]

Sooner or later someone is going to come up with a reliable heat exchanger control. It could be as crude as the old diverter valve using the bimetal spring. Remember the one used on the Chev 283's that applied back pressure on one exhaust manifold to help preheat the carb base?

Yeah. We called them "heat riser valves" IIRC. Could easily work with a simple cable control.

J.R.
SoCal

[joat]

the plastic grey electrical tubing works fine (instead of exhaust tubing) and doesn't rattle ..... use some Great Stuff to seal the ends after the heater hoses are run thru it ....

[Fatmobile]

I redid the system on the Fatmobile.
I ran the hoses inside the body:


It is a 2 door, so the lines ran in the rocker panels under the door.
I drilled a hole in the front and came out in the wheel well:

There was already a rust hole so I ran the lines into the raintray.
You aren't going to like the way this looks and wouldn't want to do this to your car,...:

Next time I try this I'm going to leave the vegy filter in the wheel well. The '84 and some of the cabbys have plastic fender liners, that protect everything in the wheel well from flying road debris.