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View Full Version : Carb Heat Shield is a Big Help



TWChamp
09-15-2016, 05:09 AM
In the 60's and 70's when my Studebakers were my only cars I never had fuel related problems, but today's gas boils at a lower temperature and has caused me problems with hot restarts and when the car sets for more than a couple days. If I stopped for a few minutes the heat would boil the fuel in the carb and I'd have to crank a lot to get the engine restarted. BTW, I only use the better gas without the corn crap, unless I'm far from home and can't find the good gas.

I made this heat shield from a thin sheet of stainless steel, and got it installed just in time to go on tour with the club last Saturday. This has made a big improvement in hot and cold restarts. Yesterday the 1950 Champion fired right up after setting since Saturday, and again it started right away after several short stops. Also notice the split white plastic tubing I slipped over the fuel line from the pump to the carb. I like white because it reflects the heat more than black.

The Tee fitting by the carb is a small copper line running to a low pressure gauge I hung off the bottom of the dash, so I can monitor fuel pressure until I'm sure everything is finally working right. I'll probably just leave it on until I reinstall my mechanical pump.

58425

52-fan
09-15-2016, 11:53 AM
Nice to hear about something that works. We have non ethanol gas available here and, except for evaporating out of the carb after a few days, I have no problems with restarts. I wonder what will happen when I drive through an area where only the ethanol laced fuel is available.

TWChamp
09-15-2016, 03:24 PM
My 6 volt battery is over 10 years old, so this heat shield not only makes the driving experience much more pleasant, but will save the starter and battery from wearing out before their time.

LovelandJoe
09-15-2016, 04:32 PM
Thank Tom. I was trying to think of a shield design but this looks perfect. Do you think I should coat the underside with a spray rubber like Flex Seal to retard heat transfer. Great to get the opinion of a real mechanic.

RadioRoy
09-15-2016, 04:54 PM
Thank Tom. I was trying to think of a shield design but this looks perfect. Do you think I should coat the underside with a spray rubber like Flex Seal to retard heat transfer. Great to get the opinion of a real mechanic.

I would think that having the underside as shiny and reflective as possible would be best.

That is a nice heat shield on TWChamp's car, BTW. There is one similar on my 50 Commander, but not as nicely crafted.

TWChamp
09-15-2016, 05:16 PM
I agree with RadioRoy that the bottom side should be shiny to reflect the heat. Luckily this stainless is very shiny on both sides, and the top side still had the protective vinyl on it.
I need to go back to the metal yard and buy some more. I bent it by clamping it at the angle I wanted with a 1" diameter steel pipe in the vice, then just pulled it around the pipe to get the slant I show.

Dan Timberlake
09-15-2016, 06:50 PM
Was the pressure gage installed before the shield was in place? I'd sure like to know the pressure during the various hard start episodes.

LovelandJoe
09-15-2016, 09:21 PM
Thanks again Tom for the design and even instructions on how to bend it. Finding the white tubing was more difficult than the forming of the stainless. Great idea

TWChamp
09-15-2016, 10:49 PM
I was lucky enough to find a roll of the white split plastic wire tube at a swap meet for only a couple bucks. I should have bought all 3 rolls the guy had because I looked on ebay and that stuff is quite expensive.

Yes, I had the pressure gauge installed for the past 4 months before I made the heat shield. I'm running a 12 volt Holley pump on 6 volts, and 6 volts still makes the pump put out 10 or more PSI, so I've been experimenting with various ohm resistors to drop the voltage and get the pressure down to a couple pounds pressure. The car runs fine on one or two pounds pressure, but it was the manifold heat boiling the gas that was giving me problems. Now with the heat shield installed the boiling gas problem is solved, and the car is fun to drive again.

Mike Van Veghten
09-16-2016, 07:32 AM
Carburetor heat shields worked in the 60's, no reason they shouldn't work now.

Mike