greenghost45

Thanks for the reply. I have also used a handheld laser sighted unit and they are handy. I thought that maybe you had a permanent installation but the handheld probably works just fine. I installed a digital oil temperature gauge in a tee in the banjo bolt on the injector pump, that feeds fuel from the filter. I certainly see higher temperatures when idling, as compared to highway cruising.

dieselluvr

I thought about doing that too but the temp that matters the most is the temp of the fuel as it enters the injectors. You could maybe wrap your sensor around one of the injector housings with silicone tape and dielectric grease somehow for that on the go reading.

greenghost45

My first "cut" at a fuel temperature gauge was a $3 digital aquarium probe taped tightly to the fuel supply hose just downstream of the fuel heater….. talk about cheap and low tech! I think I'll stick with the new sensor mounted in the tee on the IP. I can always use the laser gun and compare to the permanent gauge and get a good idea of what's going on. I have learned that the fuel temperature varies dramatically based upon outside air temperature and driving conditions.

dieselluvr

Ok. This is all a work in progress. My current system is almost completely different. Partly due to 3 way valve failures( which no one sells any more due to this), electric fuel pump failures, relay failures, all kinds of stuff.

​​​​​​Good thing is I've put over 100k on WVO and with today's fuel prices that comes out to about $25,000 in savings.

If I were to do it again. I would use relays to run starter solenoids on anything that draws more than 5 amps because USA made relays don't exist and the Chinese ones don't hold up to their 30A ratio.

My latest system requires 2 electric fuel pumps. I'm using Raptors since they seem to be the only ones that last but even those have failed on me once. Luckily they are rebuildable.
1. I use a starter solenoid to provide power to everything when the key is on. My dash has toggle switches marked WVO, Heat and Return Line.
2. The WVO switch on the dash sends power to the WVO relay which powers the WVO pump.
3. The WVO Relay (when switched off ) sends power to the Diesel Relay.
4. The Diesel Relay ( when powered by the WVO system being off) sends power to the Diesel fuel pump which provides diesel to the injection pump.
5. The "HEAT" switch on the dash powers a relay that turns on the filter heater and the injector line heaters. When it's cold outside I turn these on as soon as I go to start the truck.
6. The Return Line switch sends power to the Return Line Solenoid (normally closed). a: when powered "on" opens up and sends the return fuel line fuel to the WVO Tank. b: when "off" ,closes, sending return fuel line fuel to the Diesel Fuel Tank.
7. There are 3 check valves in the system. One just past each fuel pump (WVO and diesel) to prevent backflow, and one for the diesel tank return line.
8. The Return Line Fuel line has a "T" before the Return Line Solenoid Valve. When the valve is open return line fuel passes through it to the diesel tank. When it's closed it takes a few psi to open up the check valve that allows fuel to the WVO tank.

All this seems complicated but if any solenoids fail the truck runs on diesel and NO WVO ever passes through to the diesel tank contaminating the diesel fuel which is REALLY important when it's really cold outside. If the return line solenoid valve fails, return line fuel goes to the WVO tank regardless of what it actually is. Again preventing diesel fuel contamination. Keeping spare fuses and relays in the glove box is important.



Fuse panel and relays galore! Oh my!

return line stuff
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