looking for heat shield pics and dimensions

[im3crazy]

does anybody have a pic and rough dximensions for a gas tank heat shield they are willing to share? i found yet another gas smell factor - really HOT gasoline cannot be good! i also posted a WTB in classified for part. Thanks!

[c.d.iesel]

THE SPECIAL HEAT SHIELD IS THE SAME LENGTH AS THE TANK,

and pre shaped with a curve to wrap around the tank side,

and it's a sandwich of tin and heat resistant material.

it has 3 holes which align with the 3 holes in the trunk floor

for the tank mouting. The tank needs to be lifted up so the shield

goes against the floor, and when the tank is lowered,

it holds the shield over against the tank - with 2 rubber

buffers preventing rattles

locate one in yer local 02 bone yard,

or fabracate one from the metal of your choosing

[im3crazy]

thanks diesel for your detailed response. This is exactly what I needed to make one up if I can't find one. I'm not sure this model had one originally, but it sure needs one now! I dont like the idea of really hot gas for safety and combustion reasons.

Dave

[BillWilliams]

Me thinks the square light cars had these, not the round light cars.

Hummm - hot gas? How did you determine that?

[jimk]

Me thinks the square light cars had these, not the round light cars.

Hummm - hot gas? How did you determine that?

Bill,

I added one to my car because it is fuel injected and the return fuel is quite warm after passing thru the fuel rail. In time the entire contents of the tank is cyclet thru the fuel system and the fuel in the tank becomes warmed. So another heat source isn't wanted. The 02 tanks are vented tanks unlike the modern cars that are pressure retained. The fuel temperature in those cars builds pressure in the tank and stops evaporation and fuel pump cavitation from flashing fuel. In the vented tank the fuel will boil at a much lower temperature.

Also with exhaust gas running between 900°F around town and up to 1050°F at highway speeds (into a good wind), the heat sheild is effective as a radiation shield and not so much as a convective shield as air is moving past. (Hold your hand about 2 inches from a 1000°F metal object and you feel the heat no matter what the air temperature is.) I have an Isspro exhaust pyrometer, so I know what the exhaust temp is (and not just a guess).

So to not ask for a fuel pump problem, I have a factory heat shield on my car.

[BillWilliams]

Something to think about.....

[c.d.iesel]

as Martha Stewart would say - " it's a good thing "

[im3crazy]

Bill: I discovered this partly as my ongoing gas smell search. I was working on a slight misalignment on the filler pipe to rubber cowl and preparing to move the gas tank slightly within what the existing holes would allow.

I drove the car to work and returned and started to do the adjustment. When I felt the area around the tank near the exhaust it was almost too hot to touch. This read over 150F with my infrared therm. The gas at the engine fuel filter was 120F, and this was really alarming to me.

I'm sure you're correct that my (69 production) '70 titled 02 did not have these, but I'm convinced it needs it. May of 08 I had a Car-B-Que with my fully restored '75 450sl... total loss. The cause was deteriorated NEW EFI rail rubber due to ethanol in the gas. I also experienced this gas line deterioration with my R100 BMW cycle. So I've become very concerned re gas issues!

Also, re combustion. I've not done the real number research, but I think hot gas may not be the most efficient MPG approach and may significantly affect timing/ignition parameters. I hope others will weigh in on this.