Rear Tires: Where does it get tight on compression?

[Herbie]

Hey guys, this is a bit of a weird one, but stay with me here. Assuming I run a 30" or 30.5" tire with a 4" Overland lift, where in the rear wheel well do things get tight or rub on hard compression? (Like if I get pretty crossed up...)

It seems that it will be more likely to rub at the front of the wheel well, or maybe at the rear, but that there should be some clearance at the top of the well. Does this sound right? I guess its hard to photograph that side because all the wheeling picks I've seen show the "unloaded" wheels...

The reason I ask is that while I'm speccing out the interior on my van, I'm looking for a place to put the furnace unit. Oddly enough, one of the most convenient places would be inside the passenger-side rear trim area, just above the rear wheel well (removing the cubby, etc.). This offers a lot of advantages that fit with the rest of my interior build, but the downside is that the furnace intake/exhaust ducts go straight down from the blower, which would mean they exit at the top of the rear wheel well. I'm sure I could route them back up under the rest of the body pretty tightly, but there would be some tubing up there, and I'm trying to figure out if it'll get squashed if I really compress the rear on the right side...

Thanks!!

[LiftedAWDAstro]

The tires hit the front of the wheel well mostly. I don't think I ever heard of issues at the rear. Under extreme articulation you can get some tire rub in the center of the wheel well along the inside where the wheel hump is on the inside of the van.

Although this was not extreme, this is a 32 x 11.5 stuffed partially. The tire never hit the rear, only the front of the well.



Here is a 31 x 10.5 mostly stuffed. Hard to see but again, I don't think Bill ever had issues in the rear of the well.



And here is Sandfly's van stuffed...

[Herbie]

Great photos, thanks!

Hrm... looks tight enough that I probably shouldn't do what I was planning.

Here's a drawing that gives a good idea of the plumbing. The intake/exhaust on the bottom are about 1" bore, so probably about 1 1/4" OD, which may be too big to have in that area and not get squished...

[LiftedAWDAstro]

Yeah you might crush the pipes. How about mounting it in the same place but higher and then run the intake and exhaust lines down around the wheel well and out the floor.

[Smiliesafari]

Would it be possible to rotate the unit so the plumbing was in a different position?

[kamenz]

Herbie,I installed the same unit in the area of the side door ( slider ) under the floor against the frame rail and cut a hole in the floor behind - under the passenger seat with an warm air diffuser installed.Works great, is out of the way and nothing will hit it.

[Herbie]

Herbie,I installed the same unit in the area of the side door ( slider ) under the floor against the frame rail and cut a hole in the floor behind - under the passenger seat with an warm air diffuser installed.Works great, is out of the way and nothing will hit it.

Any pictures? What sort of diffuser? Just one of their round ones or did you fit it to something "flat" that spread the warm air out?

Yeah, I'm starting to come around to external mounting. The Espar install manual has the warning "Do not mount the heater outside the vehicle, unless care is taken to protect the heater from the weather", but doesn't go any further. After some more research, I see that the T4 and T5 VW guys are mounting them externally with seemingly no ill effects. Doing this would also "export" some of the noise outside. I'd also like to mount the fuel tank outside for safety, but getting an easy fill would mean putting in another filler neck etc. One bus owner just took out the fridge from the "kitchen" and mounted the heater and a small fuel cell inside the cabinet, and just uses a funnel to fill! Convenient for sure...

Smiliesafari, to answer your question, it seems that the VW guys are also mounting them rotated 90* along the long axis (that is with the combustion plumbing coming out horizontally) The manual says only that it must be FLAT, so I'm assuming more or less level (again, along the long axis). It seems that mounting with the plumbing pointing UP would be bad as there is water vapor in the exhaust that you need to drain away...

Failing any of that, it seems that the boat guys are doing something more like what LiftedAWDAstro suggests. They're sealing the unit against a "bracket" up above the hull, then just routing the combustion plumbing through goosenecks and through-hull fittings (since they have water ingress issues to worry about). My initial pass of the install manual led me to believe that it was necessary to seal the unit directly to the floor, now it seems there's quite a bit of flexibility here...

[Herbie]

OK, now I remember why I thought the unit had to be installed exhaust down: Because the manual says so!

Heater must be mounted on flat horizontal surface providing an air tight seal between heater and vehicle.

However, like I said, the VW guys are getting away with it... I'll fire off an email to Espar and see what they say.

[kamenz]

Yes I used one of the round diffusers and there is no problems and yes I also installed some sheet metal shielding after installation covering the area between rail and rocker panel.For fuel supply I cut the fuel return line installed a tee and used a large fuel filter -pint size- maybe larger and mounted it right by the heater with the pump below it,so no suction needed.Mine is a Ebersbaescher .The fuel return line to the tank has a enough back pressure to fill the filter.

[mdmead]

This is a very interesting thread. I'd like to see some pics!

[astrozam]

And here is Sandfly's van stuffed...

LMAO, ahhh the good o'le days. You guys had some pretty cool wheelin trips

[kamenz]

Matt,pls. don't let my crawl underneath the van,remove the sheet metal and take some pictures.I had a hard time installing everything without lift and no hoist,specially at my age.I only did this because I got this unit used for $50. The guy could not figure out how to make the unit work.

[T.Low]

It is indeed an interesting thread. My only worry is that by the time I go to put a heater in my van, I won't remember that all the heater info is in a rear tire compression thread.

[Herbie]

It is indeed an interesting thread. My only worry is that by the time I go to put a heater in my van, I won't remember that all the heater info is in a rear tire compression thread.

Don't worry Tom. Once I move from Research phase into Development phase, I'll have a proper build thread. I haven't started one yet because thus far it would consist of:

1)Bought van
2)Bought wheels on craigslist
3)Bought van conversion seat on craigslist
4)Removed headliner, made some templates

When I have some real forward progress, it'll get documented!