|
|
Joined: May 2005
Posts: 132
Shade Tree Mechanic
|
OP
Shade Tree Mechanic
Joined: May 2005
Posts: 132 |
This maybe a dumb question.. but I purchased a NRS fuel sending unit for my 39' and the rheostat winding is completely exposed. The original unit had the winding sealed in a can. Since there is electricity in the winding and it is sitting in gasoline, is this not a hazard?
|
|
|
|
|
Joined: Dec 2001
Posts: 10,379 Likes: 1
Technical Advisor ChatMaster - 10,000
|
|
Technical Advisor ChatMaster - 10,000
Joined: Dec 2001
Posts: 10,379 Likes: 1 |
The original was not really sealed. It just had a protective cover over it. Unless you get the correct mixture of fuel and air there can be no explosion or fire. Most fuel tank explosions are cause by viewing the fuel level aided by the light from a match. 
RAY Chevradioman http://www.vccacolumbiariverregion.org/1925 Superior K Roadster 1928 Convertible, Sport, Cabriolet 1933 Eagle, Coupe 1941 Master Deluxe 5-Passenger Coupe 1950 Styleline Deluxe 4-Door Sedan 1950 Styleline Deluxe Convertible 2002 Pontiac, Montana, Passenger Van 2014 Impala, 4-Door Sedan, White Diamond, LTZ 2017 Silverado, Double Cab, Z71, 4X4, White, Standard Bed, LTZ If you need a shoulder to cry on, pull off to the side of the road. Death is the number 1 killer in the world.
|
|
|
|
|
Joined: Jan 2002
Posts: 30,701 Likes: 141
ChatMaster - 25,000
|
|
ChatMaster - 25,000
Joined: Jan 2002
Posts: 30,701 Likes: 141 |
The modern car has an eletric motor in the fuel tank - to run the fuel pump.
Gene Schneider
|
|
|
|
|
Joined: Dec 2001
Posts: 11,162
ChatMaster - 10,000
|
|
ChatMaster - 10,000
Joined: Dec 2001
Posts: 11,162 |
Yes and it is a cause of a shorter pump life when you let the fuel level get below a eighth of a tank. The gasoline cools the electric motor while it is running (anytime the engine is running) and the heat will be transfered up thru the cable when the pump is running with a low level in the tank. Sometimes a shorted cable will result from consistantly running with a minimum amount of fuel in the tank or the motor will short and also short the cable requireing the pump, sending unit and cable to be replaced, ( several hundred dollars on a 96 Roadmaster or Caprice, a fire hazard is not too high because air isn't usually present in the non-vented tank with the fuel being recirculated, mostly only liquid gasolne and vaporus gasoline fill the tank.
Life's a long winding trail, love Jesus and ride a good horse!
|
|
|
|
|
Joined: May 2002
Posts: 6,149 Likes: 42
ChatMaster - 6,000
|
|
ChatMaster - 6,000
Joined: May 2002
Posts: 6,149 Likes: 42 |
With the fuel guage sending unit, the current flow is not sufficient to cause a spark anyway.
With the in tank electric pumps, MrMack is right and with all that I have seen the actual motor is fully sealed and the fuel only flows around the motor cavity. If fuel gets into that section it shorts out the motor and it dont work no more.
Tony
1938 1/2 ton Hope to drive it before I retire
|
|
|
|
|
Joined: May 2002
Posts: 6,149 Likes: 42
ChatMaster - 6,000
|
|
ChatMaster - 6,000
Joined: May 2002
Posts: 6,149 Likes: 42 |
With the fuel guage sending unit, the current flow is not sufficient to cause a spark anyway.
With the in tank electric pumps, MrMack is right and with all that I have seen the actual motor is fully sealed and the fuel only flows around the motor cavity. If fuel gets into that section it shorts out the motor and it dont work no more.
Tony
1938 1/2 ton Hope to drive it before I retire
|
|
|
|
|
Joined: Dec 2002
Posts: 689
Oil Can Mechanic
|
|
Oil Can Mechanic
Joined: Dec 2002
Posts: 689 |
I share MrMack's comment about the gas cooling the pump motor. I had an old Volvo that had the early generation Bosch mechanical fuel injection with a submerged fuel pump. The mechanical injectors would open only when the cylinder was on the intake stroke (negative pressure) and with sufficient (positive) pressure on the fuel line. With the tank near empty the 'heat rise' in the motor reduced the effective psi to the injectors, making it very difficult to restart the warmed up engine. Starting the cold engine was a snap, but restarting was a bear! Sorry to say it took me many repair attempts before I figured this out.
Coach
|
|
|
|
|
