StingrayL82 wrote:
Just a thought for you, Eric....if you're looking for a way to return the fuel to the tank, and the carb doesn't provide for that, get a fuel filter that has a single inlet and dual outlet, like the Jeep used. The top outlet is used for the return. Jeep Fuel Filter
Just a thought for you, Eric....if you're looking for a way to return the fuel to the tank, and the carb doesn't provide for that, get a fuel filter that has a single inlet and dual outlet, like the Jeep used. The top outlet is used for the return. Jeep Fuel Filter
Hmmm ... I'm intrigued. I may buy one to experiment with.
Low pressure fuel systems (mostly engine driven pumps) don't usually need a return line. (Float needle valves are usually enough to resist fuel line pressure in low pressure systems.)
One of the problems with in-tank and inline fuel pumps (close to the tank) is how to get the electric pumps turned off in an accident. (Pusher pumps, versus suckers, are almost always better.)
At CarQuest, I often cautioned customers buying aftermarket electric inline fuel pumps. Especially if they appeared hellbent on a "bigger is better" approach.
The filter's return line may partially alleviate fire risk. Return line won't do much for a fuel line fracture or break but there is a potential for minimizing risk.
1970 Explorer Class A on a 1969 Dodge M300 chassis with 318 cu. in. (split year)
1972 Executive Class A on a Dodge M375 chassis with 413 cu. in.
1973 Explorer Class A on a Dodge RM350 (R4) chassis with 318 engine & tranny from 1970 Explorer Class A
Griff in Fairbanks wrote:
Hmmm ... I'm intrigued. I may buy one to experiment with.
Low pressure fuel systems (mostly engine driven pumps) don't usually need a return line. (Float needle valves are usually enough to resist fuel line pressure in low pressure systems.)
One of the problems with in-tank and inline fuel pumps (close to the tank) is how to get the electric pumps turned off in an accident. (Pusher pumps, versus suckers, are almost always better.)
At CarQuest, I often cautioned customers buying aftermarket electric inline fuel pumps. Especially if they appeared hellbent on a "bigger is better" approach.
The filter's return line may partially alleviate fire risk. Return line won't do much for a fuel line fracture or break but there is a potential for minimizing risk.
Hmmm ... I'm intrigued. I may buy one to experiment with.
Low pressure fuel systems (mostly engine driven pumps) don't usually need a return line. (Float needle valves are usually enough to resist fuel line pressure in low pressure systems.)
One of the problems with in-tank and inline fuel pumps (close to the tank) is how to get the electric pumps turned off in an accident. (Pusher pumps, versus suckers, are almost always better.)
At CarQuest, I often cautioned customers buying aftermarket electric inline fuel pumps. Especially if they appeared hellbent on a "bigger is better" approach.
The filter's return line may partially alleviate fire risk. Return line won't do much for a fuel line fracture or break but there is a potential for minimizing risk.
Something like this? Crash cut-off switch
Fred
Retired Army Guy
2005 Monaco LaPalma 37PST
Workhorse W24 chassis
8.1L Vortec
Allison 2100 MH
Onyx Color Scheme
Yeah and no. That's an inertial switch, just like what's OEM in many automobiles and light trucks. I'm looking for an alternative because I've seen too many problems due to false sensing.
Linked webpage wrote:
THIS IS HEAVY MOTION ACTIVATED SO IT IS NOT RECOMMENDED FOR HEAVY OFF ROAD USE
THIS IS HEAVY MOTION ACTIVATED SO IT IS NOT RECOMMENDED FOR HEAVY OFF ROAD USE
I've said many time I get way, way, waaay off the pavement. Honestly, you wear seatbelts in my vehicles to keep being thrown to the floor, into the dash, and so forth.
BTW -- I looked at the ThermoQuad Phenolic Bowls link you provided and bookmarked (twice) the website. I saw Carter YF and thought, because I'm in the mood to paraphrase movie quotes, "Carter YF. Now there's a carburetor I've not heard in a long, long time. A long time."
Griff in Fairbanks wrote:
...BTW -- I looked at the ThermoQuad Phenolic Bowls link you provided and bookmarked (twice) the website. I saw Carter YF and thought, because I'm in the mood to paraphrase movie quotes, "Carter YF. Now there's a carburetor I've not heard in a long, long time. A long time."
...BTW -- I looked at the ThermoQuad Phenolic Bowls link you provided and bookmarked (twice) the website. I saw Carter YF and thought, because I'm in the mood to paraphrase movie quotes, "Carter YF. Now there's a carburetor I've not heard in a long, long time. A long time."
I’m still running the original YF in my ‘76 CJ-5. I went to California last summer and got 21MPG on the way there.
If you go off-road, why couldn’t you run the electric pump AND the mechanical fuel pump, along with that cut-off switch; if the switch accidentally kicked off, the mechanical would act as a backup.
StingrayL82 wrote:
I’m still running the original YF in my ‘76 CJ-5. I went to California last summer and got 21MPG on the way there.
If you go off-road, why couldn’t you run the electric pump AND the mechanical fuel pump, along with that cut-off switch; if the switch accidentally kicked off, the mechanical would act as a backup.
I’m still running the original YF in my ‘76 CJ-5. I went to California last summer and got 21MPG on the way there.
If you go off-road, why couldn’t you run the electric pump AND the mechanical fuel pump, along with that cut-off switch; if the switch accidentally kicked off, the mechanical would act as a backup.
They were still using the YF in 1976? (I assume your jeep had the four banger flathead.)
My experience with a YF was on a 1947 Willys Overland wagon.
I'm not worried about myself. I'm going to power the pumps through the ignition switch RUN position, with two cut-offs. One will be a prominent manual switch, within easy reach, and a relay off the oil pressure switch. Manual switch because it's faster than the ignition switch ... and provides theft prevention. Oil pressure relay in case I'm unable to cut the manual and ignition switch.)
Mostly, I'm looking for ways to make things safer for other people.
Griff in Fairbanks wrote:
They were still using the YF in 1976? (I assume your jeep had the four banger flathead.)
StingrayL82 wrote:
I’m still running the original YF in my ‘76 CJ-5. I went to California last summer and got 21MPG on the way there.
If you go off-road, why couldn’t you run the electric pump AND the mechanical fuel pump, along with that cut-off switch; if the switch accidentally kicked off, the mechanical would act as a backup.
I’m still running the original YF in my ‘76 CJ-5. I went to California last summer and got 21MPG on the way there.
If you go off-road, why couldn’t you run the electric pump AND the mechanical fuel pump, along with that cut-off switch; if the switch accidentally kicked off, the mechanical would act as a backup.
They were still using the YF in 1976? (I assume your jeep had the four banger flathead.)
They sure were. AMC stopped using it in 1978, when they introduced the BBD.
No, my CJ-5 has the 258 I6 & T150 3-speed. The four-cylinder wasn’t available in ‘76, only the 232 I6, the 258 I6 & the 304 V8.
The four-cylinder didn’t come back to AMC/Jeep until 1980, with the GM Iron Duke 151cid.
I was a littlebit surprised, as i couldn't finde a fuel return line at the carburetor.
A very simple way to cut the fuel supply when the engine is not runnig (in case of an accident) would be an emergency shutdown by a standard relais and oil pressure sensor. No oil pressure = no power at the fuel pump.
Or by the D+ signal from the alternator to relais and the relais switches the fuel pump on and off.
* This post was edited 04/19/18 03:57am by Eric Hysteric *
'79 Dodge Sportsman 5.9 LA 360 TEC Campmate
Eric Hysteric wrote:
Thank you guys! Very interesting discussion and a lot of informations and links!
I was a littlebit surprised, as i couldn't finde a fuel return line at the carburetor.
A very simple way to cut the fuel supply when the engine is not runnig (in case of an accident)would be an emergency shutdown by a standard relais and oil pressure sensor. No oil pressure = no power at the fuel pump.
Or by the D+ signal from the alternator to relais and the relais switches the fuel pump on and off.
Thank you guys! Very interesting discussion and a lot of informations and links!
I was a littlebit surprised, as i couldn't finde a fuel return line at the carburetor.
A very simple way to cut the fuel supply when the engine is not runnig (in case of an accident)would be an emergency shutdown by a standard relais and oil pressure sensor. No oil pressure = no power at the fuel pump.
Or by the D+ signal from the alternator to relais and the relais switches the fuel pump on and off.
That's part of what I was suggesting. I need to work on it more conceptually. Mostly to see if there's a way I can break it or find a weak point that could result in an unacceptable failure. (Yes, there is such a thing as an acceptable failure ... sometimes called a deliberate fault.)
Alternator connection not acceptable. Can explain if you'd like but explanation will be somewhat lengthy. (Involve how battery, voltage regulator, and alternator works together as a system during normal operation.)
Here's the tentative analysis:
1. Power from ignition switch => normal operation of electric fuel pump. Switch on implies pump on, switch off implies pump off.
2. Manual switch within easy reach => emergency shut off if vehicle operator is capable.
3. Oil pressure switch and relay => emergency shut off if vehicle operator is rendered incapable.
Emergency condition logic:
-- Manual switch is fastest due to linear operation. (Ergonomics)
-- Ignition switch is slower due to rotational operation. (Ergonomics)
-- Oil pressure/relay is slowest due inherent oil system lag.
Notes at this point in project:
a. Pump control system needs to be simple. Right now, I have it at three additional components, not counting ignition switch and pump.
b. Significant issues exist related to using oil pressure. May not be doable or may require additional components and an unacceptable degree of complexity.
On fuel return line topic: If I recall correctly, your dual fuel conversion has a valve for shutting off gasoline when running on propane. If so, fuel return line definitely advisable if still using mechanical engine-driven fuel pump. May be easier to shut off pump simultaneous with valve closing if you're using an electric fuel pump.
Aside: Do you have a oil pressure gauge or indicator light? (A question leading to more discussion in the future.)
Hoppe
2011 Dodge 1500 C'boy Caddy
2000 Jayco C 28' Ford chassis w V-10 E450
Doghouse 36' or so Trophy Classic TT