ZD9 WMO Fuel Heater

[BioFarmer93]

Since the weather cooled off and we've had a couple nights in a row below freezing, I've noticed that my WMO is thickening up enough to affect timing (white smoke with agressive throttle instead of black.) I've flipped back and forth between tanks and assured myself that this is what is happening. Anyway, walking out of the parts store a few days ago I heard a familiar sound, there was a guy getting his alternator checked out on an '89 extended cab so I walked over to check it out. He was running straight WVO and had a fuel heater made from an M-Benz glow plug and some pipe. It was kind of a hack job but it worked. I thought to myself "-I can do better than that..." So I did, I had some spare ZD9's so I went to Home Depot and got a 1/2"T, close nipple & cap, then 2 each brass 1/2to3/8 reducers and 3/8 hose barbs. Had to hit Ace for a metric tap to fit the ZD9. Hit A-Z for a 30A relay & 30A blade fuse holder. A little re-org on the filter locations and installation of a lighted rocker switch immediately next to the tank selector switch and we were in bidness. Apparently when a ZD9 is completely submerged in fuel it can be run continuously just like a Benz plug. It's made a radical difference in the way the motor runs on WMO at below freezing conditions. If anyone's interested I'll get a couple pics of it this evening.

 

[FordGuy100]

Thats kinda what I was thinking. Heck, you dont really need a ZD9 in that application, you could probably use an autolite or something like that.

 

[BioFarmer93]

Thats kinda what I was thinking. Heck, you dont really need a ZD9 in that application, you could probably use an autolite or something like that.

-True, but I would have had to buy one

 

[david_lee]

this is something i never would have thought about doing, but i might have to now. the only thing i would change is the glowplug selection(i understand you used what you had on-hand). given your application, it seems to me that the 12v glowplugs from the chevy's would be well suited for this. the slower heating wouldnt be an issue worth worrying about, and they are actually made to run on 12v. but it works they way you built it and why fix it if it aint broke?

 

[WrickM]

there is some concern amongst folk about using glowplug heaters that put the glowplug in direct contact with fuel. just fyi. There has been ignition issues with a few heaters.

 

[WrickM]

here's a really nice one that is a good model for a build

http://cgi.ebay.com/ebaymotors/Vegetable-Oil-Fuel-System-SVO-WVO-Heater-Exchanger-_W0QQcmdZViewItemQQhashZitem415504a293QQitemZ280599241363QQptZOtherQ5fVehicleQ5fParts

more like what you yourself built. not bad just to be used with a little caution
http://cgi.ebay.com/ebaymotors/Vegetable-oil-Biodiesel-heater-Diesel-Engines-WVO-_W0QQcmdZViewItemQQhashZitem35abd20676QQitemZ230515934838QQptZOtherQ5fVehicleQ5fParts

 

[93turbo_animal]

yep did this a long time ago but used a PSD glow plug since they can burn a lot longer with out burning out. I drilled my filter housing and put it there works great and you only need a 10-15 amp fuse depending on how good your wiring is

 

[BioFarmer93]

here's a really nice one that is a good model for a build

http://cgi.ebay.com/ebaymotors/Vegetable-Oil-Fuel-System-SVO-WVO-Heater-Exchanger-_W0QQcmdZViewItemQQhashZitem415504a293QQitemZ280599241363QQptZOtherQ5fVehicleQ5fParts

more like what you yourself built. not bad just to be used with a little caution
http://cgi.ebay.com/ebaymotors/Vegetable-oil-Biodiesel-heater-Diesel-Engines-WVO-_W0QQcmdZViewItemQQhashZitem35abd20676QQitemZ230515934838QQptZOtherQ5fVehicleQ5fParts

! The second one there looks almost identical to what I made except for the thermostat mounted on the back.

 

[BioFarmer93]

there is some concern amongst folk about using glowplug heaters that put the glowplug in direct contact with fuel. just fyi. There has been ignition issues with a few heaters.

I will admit that ignition was a concern, so it is mounted in a manner that ensures that the glowplug is always submerged in fuel. Where the one from ebay that you showed me has the glow plug, mine has a nipple (ground down a little shorter) with a pipe cap. At full insertion into the pipe cap the plug's tip just barely extends into the fuel stream coming from the side. As a safety rule for this I have determined that the engine gets started first to ensure an uncompromised fuel flow, then it can be turned on.

 

[Dieselcrawler]

i sorta like the thermostat idea, only is on when needed then. no need for on and off toggle.

 

[sassyrel]

thing that bothers me--when i was running wmo--7 years ago--pure--at 57,,the stuff wouldnt almost flow!! so even if this was somewhere forward,,the fuel at and in the tank is still almost not fluid--sooooo, a heated tank is the only solution to the inevitable,,along with insulated and heated forward lines--

 

[WrickM]

BioF The trick is just to be really careful about getting air in the line. It's a good idea and i would use one i just wanted to be informative about any potential hazards. Not bein a downer, or at least not trying to be lol

 

[Diesel JD]

For continuous duty you could also step down the voltage to 6V provided you want to keep using a ZD9 or similar 6.9/7.3 glow plug but I guess that would result in less heat being created. Obviously the oil dissipates a lot of the heat that the glow plug produces and which would normally burn it out if it were to stay on longer than 10-15 seconds.

 

[BioFarmer93]

BioF The trick is just to be really careful about getting air in the line. It's a good idea and i would use one i just wanted to be informative about any potential hazards. Not bein a downer, or at least not trying to be lol

It's cool- didn't take it as a slam, and I wholeheartedly agree... NO AIR! AIR BAD!

 

[BioFarmer93]

For continuous duty you could also step down the voltage to 6V provided you want to keep using a ZD9 or similar 6.9/7.3 glow plug but I guess that would result in less heat being created. Obviously the oil dissipates a lot of the heat that the glow plug produces and which would normally burn it out if it were to stay on longer than 10-15 seconds.

Yeah, it dissipates a tremendous amount of heat considering the fuel coming in to it is in the 30's!
I had an argument Sunday with the guy at Advance-Discount about glowplugs... Seemed I remembered them being 6volt and supplied in parallel-series. He swore up and down that they were all 12v.