After installing the fuel standpipe in the Ford Transit's tank, work could start on mounting the gasoline pump and the intake + exhaust pipes under the chassis. This post describes just one of the many ways to lay out all these parts.
Respecting the Eberspacher / Webasto installation guidelines is crucial to guarantee reliable and trouble-free operation over the years. I had to ditch the Chinglish instructions that came with my diesel heater (now converted to gasoline) as they were factually wrong (pump upside down, etc)
In parallel, a box was built inside the cooking cabinet to host the heater. Since switching to a fuel based heater was an afterthought, after I realized that electrical heating wasn't enough, packaging ended up very tight.
But care was still taken to ensure accessibility and serviceability, and the heater can be removed with top-mounted bolts instead of the default under-chassis nuts. No one wants to have to crawl under a camper van in Winter in case of issues...
After priming the fuel line, and using the proper controller settings, the beast roared on the first try. The temperature climbed from ~40 to 60°F (4-16°C) in about 40', way faster than the hours it took before with the 800-but-really-300W heater.
Happy and warm Winter trips to all !
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Heater Cabinet
Once filled with enough courage-in-a-bottle I finally could stomack making a huge hole in the floor of the van, using a 5" hole saw:
The heater is raised on a pedestal to provide enough space to suck in cold intake air from the floor. It also provides a ~6" tall hole to protect the connections to the fuel line and the intake + exhaust pipes from debris and slush kicked up by the tires.
The whole box is lined with 1/16" (1.6mm) aluminum sheets to increase fire resistance and provide more time for the occupants to react, if needed.
Four 6mm holes were drilled in the corners of the 60mm turret, to match the mounting holes in the pedestal. The latter have an embedded M6 T-nut each, so the heater can now be secured with 4 top-mounted bolts.
Note the HVAC duct used in the hole to protect the cabinet / subfloor / insulation / chassis from road crap, exhaust heat, etc. It extends ~0.5" (12mm) down under the chassis. It was made out of a 6" (15mm) diameter duct pipe, cut to size with tinsnips.
A 1/4" (6mm) thick aluminum plate was hand fabricated, with mounting holes for the heater's underside posts (see last pic), and four 6mm holes matching the pedestal's.
Once the heater is bolted onto this plate, it then sits on top of the turret and 4 M6 bolts secure the assembly to the cabinet.
Custom rubber gaskets between the plate and the turret, and between the turret and the cabinet, were also made to prevent gases from under the chassis from creeping back into the living space.
Accessing the pipes under the heater can now be done from inside:
Done !
Installing the Pump & Fuel Line
The pump, fuel filter and pulse damper were all mounted on a holder made out of a 1/8" (3mm) thick aluminum flat bar. It was bolted to the chassis thanks to rivet nuts inserted in the existing holes in the Ford Transit beams.
The most critical layout requirement is that all the elements must point upward, from the pump to the heater. This helps continuously evacuate the air bubbles resulting from cavitation in the pump. If not, should a number of bubbles coalesce and make their way to the burner, a flameout could ensue.
A piece of 1/8" aluminum was added to the front of the holder to serve as a deflector protecting the parts from anything the front tires might kick up.
The original injector's wires are protected via several layers of heat shrink tubing. The red outside tube is of a marine type that includes a layer of glue that sealed off the whole connector+wire assembly against water ingress.
The waterproof junction box was installed on a sheet of aluminum bolted onto the chassis via rivet nuts. Cable glands protect the box from water and road crud intrusion.
The cable coming from the heater (black cable on the left) was fished through the bottom of the mid pillar. That spot is covered in foam and hides a ~10mm roundish opening. From there the cable was fished inside the wall skirt, back out under the chassis through an existing hole, and protected against chafing with a grommet.
Once done with the installation, priming the fuel line and pump system properly is essential for reliable start and operation. So some spare tubing was inserted in the output of the pulse damper and, using a 12V battery, the whole line was purged of air bubbles by manually tapping the 12V-positive wire repeatedly.
Installing the Muffler
After trying the traditional pass-through muffler and not liking the still-high exhaust noise, I switched to the newer one that provides additional noise reduction:
That muffler can easily be opened by removing 2 screws:
Which came in handy as it was then modified to provide backpressure against the exhaust gases to help stabilize the fast gasoline combustion. That was accomplished by reducing the intake hole's section thanks to a few pipes pressed into each other:
Result: the combustion now emits a continuous woosh sound, when mild individual wooshes could still be heard before. I hope this will still be the case at higher altitude than the current 5000' (1500m), when the pump rate is much slower.
The resulting noise reduction is also very noticeable, compared to the pass-through muffler. Here is the sound curve taken at 3' (1m) with Spectroid. Unfortunately I did not previously take a snapshot with the pass-through...
The muffler was mounted to a sheet of aluminum shaped to fit in the beam space in front of the rear wheel's well. It is held in place via 2 rivet nuts and by straddling the leaf suspension's bolt:
The most critical layout requirement here is that all the exhaust pipes point downward. This ensures that any water condensation gets evacuated, to avoid the formation of ice that could potentially choke the exhaust.
Installing the Intake and Exhaust Pipes
The exhaust pipe runs directly from the heater to the muffler. It was wrapped in the exhaust wrap that came with the heater to protect the fuel line from high temperature.
That wrap was a fiberglass mess: a myriad of minuscule fibers could be seen falling in the flashlight's beam each time it was touched. I immediately put on a mask and avoided contact as much as possible. Yet, my hands and wrists itched for several days.
Weaved fiberglass mats are not supposed to be choke-full of small fiber bits. Use rubber / paint gloves to handle.
The cardboard joke of an intake pipe that came with the heater kit was replaced by a section of exhaust steel pipe. The pipe's diameter was a bit too small to fit the air filter so an adapter was 3D printed, though sanding the air filter's intake nipple could have done the job too.
The air filter still needs protection though, as it is in the line of fire from the front tire which could cake it in road slush. A baffle will be installed in front of it.
A few pictures (before the fuel damper was added):
Next
The noise inside the van, coming from the hot air exhaust, is too high for my liking. Likely due to the fan's high 5000rpm speed. I am planning to build a muffler with internal baffles to tame that down. For now, here is the current sound spectrum at 3' (1m):
Posts in the Diesel-to-Gasoline heater series:
- Installing the Gasoline Heater
- Installing a Fuel Pickup Line in the Ford Transit's Tank
- Gasoline & High Altitude Heater Conversion - Success !!!
- Programmable Controller & Pump for Diesel Heater
- 'Chinese Diesel Heater' - is it Good out of the box ?
- High Altitude Gasoline Heater for Camper Vans ?
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>>> next post: coming !
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