The Gubblemobile- Series III from hell.

[ntsqd]

One thing that I'm unclear on, are the LR bulkheads aluminum or steel? I've not used Julian's vinegar trick on aluminum. No idea what the results might be.

 

[Alaska Mike]

From what I've seen, Series Land Rover bulkheads are made of compressed rust, much like the Yugo.

The front grill, bulkhead, frame, and various cappings and support pieces are made of steel. The main body panels are made of aluminum, which makes for an uneasy marriage if untreated.

 

[Correus]

One thing that I'm unclear on, are the LR bulkheads aluminum or steel? I've not used Julian's vinegar trick on aluminum. No idea what the results might be.

They're made of steel.

 

[Alaska Mike]

Today I was looking at various fuel tank options. No matter what I do, I'm likely going to replace the tank with a new version. The MPFI engines take a high-pressure pump, and I have a choice of an external (89 F-150 E2000 is common) or in-tank pump. The internal would run cooler and pump better, but it would require some doing. Here's what I have so far:

• Stock underseat tank with external pump. Easy enough to pull off, and I figure it would run around $400 with new tank, pump, and filters. Short fuel line, easy pump replacement, and minimal body modifications are other advantages. The disadvantages are the limited fuel capacity and less reliable pump. The lower capacity could be offset by installing an aux tank under the drivers seat, and the cost could be decreased in the short term by re-using the original tank (treating/sealing it). The tanks would somewhat be protected by the planned rock sliders, and skid plates are available. Interesting idea.
• Jeep 76-86 15 gallon CJ tank. I would have the option of using an internal sender (87-90 YJ) with a 91-95 YJ high pressure fuel pump, or just go with the external pump. That would give me 15 gallons of fuel capacity and a tank skid plate. I could probably pull it off for around $400 with all new parts. The main disadvantage would be limited exhaust routing options.
• Custom tank in same location as CJ tank (behind rear axle). I could tailor the size a bit to allow for exhaust routing while still keeping about a 15 gallon capacity. Price is somewhat variable depending on who builds the tank, but it isn't going to be cheap. A skid plate would be integrated into the tank, and I would have a wide variety of options for pumps. This is probably my best option, but I don't know if I can squeeze it into the budget. All depends on finding a good builder that is willing to work with me and my limited budget.

As usual, I'm waffling because the various options all have their pluses and minuses. We'll see...

 

[Funrover]

Wow, this is a great build! I wish you the best of luck with it!

 

[ntsqd]

Both types of pumps run the liquid fuel through the pump's motor. From ~1/3 tank down they'll run about the same temperature. I can see where the external might be more prone to heat related failure, but I don't read or hear of them failing left and right.

External pumps tend to be noisier than internal pumps, which I suspect is the reason that the OE's have been putting them in the tank. Any external pump mounting method needs to address both broadcast noise and conducted noise. I've been giving this some thought for my FJ project as I plan to use an external pump so that I'm not married to any particular tank. Read: Stock tank for now, but eventually I will want more capacity. If you're interested I can make a quick model of my idea and post a jpg.

FWIW I'd be wanting both tanks, the under-seat and the "CJ".

 

[Wander]

Would fuel cell be an option? You could put it behind the middle bulkhead. The double tanks under the seats sounds the easiest but sitting on top of all that fuel might make me a little nervous.

 

[Alaska Mike]

Both types of pumps run the liquid fuel through the pump's motor. From ~1/3 tank down they'll run about the same temperature. I can see where the external might be more prone to heat related failure, but I don't read or hear of them failing left and right.

External pumps tend to be noisier than internal pumps, which I suspect is the reason that the OE's have been putting them in the tank. Any external pump mounting method needs to address both broadcast noise and conducted noise. I've been giving this some thought for my FJ project as I plan to use an external pump so that I'm not married to any particular tank. Read: Stock tank for now, but eventually I will want more capacity. If you're interested I can make a quick model of my idea and post a jpg.

FWIW I'd be wanting both tanks, the under-seat and the "CJ".

The Ford pumps tend to grenade occasionally when used externally (from what I read), which require filters before and after the pump to prevent chunks moving downstream. There are a couple pump options that people say are more reliable, and I'll investigate them. Any external fuel pump would require a spare on hand at all times, where I would be less concerned about the internal pumps.

15-20 gallons is about what I'd want for now, but having multiple would definitely make longer drives easier. It's all a question of how it fits into the overall project budget. I can always upgrade/add later.

Would fuel cell be an option? You could put it behind the middle bulkhead. The double tanks under the seats sounds the easiest but sitting on top of all that fuel might make me a little nervous.

I do not want to lose any cab space, since I have 3 kids and a wife to think about. Fuel cells have their own problems in this application, although I did consider them for a while.

Series 88s all have tanks under the seats, as did early Jeeps and countless other vehicles of that era. Part of the attraction for the CJ tank is that is gets the fuel out from under me, freeing up underseat space for storage or perhaps a water tank, on-board shower system, or some other "glamping" accessory. Every inch counts in a short wheelbase vehicle.

 

[ntsqd]

I feel that part of any external pump plan should be a pre-pump filter. It does add work to the electric pump's pulling fuel out of the tank (something that they're the worst at), but I'm not willing to leave the life of the pump up to the mech. pump/carb oriented OE strainer. In the case of a custom tank there may not be any strainer at all.

 

[Yorker]

Something I thought about doing on one 88" was a CJ rear tank and one standard SWB tank, that would give 15+12 gallons of fuel which isn't too bad and the standard LR series tanks are fairly cheap and very durable even without a skid plate.

Isn't ther an extended range CJ5 tank out there that is 20 or 25g? I often wondered if it could be made to fit under an 88".

 

[Alaska Mike]

For those playing along at home, here's TeriAnn's page on the CJ/88 tank conversion:
http://www.expeditionlandrover.info/88rearTank.htm

The standard late CJ tank is 15 gallons. Most of them were made of steel. There were some later 20 gallon poly tanks, which require a different skid plate. The aftermarket has a ready supply of 15 and 20 gallon tanks in poly. The problem with the poly tanks is that dimensions vary a bit. I think the 20 gallon tank would be too big to fit, and would hang down too low. Bob had to bend the tabs on steel tank to get it between the frame rails. Chafing is a concern here for me, as I don't want to wear a hole through the tank. If I go this route, I may source a poly tank locally so I can test fit it and save on shipping a bit.

Exhaust routing is a bit of an issue with the CJ tank, since the exhaust can't exit straight out the back. I would either have to do some fancy bending to get it to exit behind the rear wheel or just put it in front of the wheel- which might put it in harm's way. The muffler would also have to run next to the transmission, and with the larger SM465 I'm not sure how much room I have to play with. It's a balancing act of priorities here.

 

[Yorker]

I've been meaning to get one of those poly 21g CJ tanks just to see how much room they take up. If you run across one first post up the dimensions.

I figured I'd run the exhaust out the side like a Willys MB but with the 2.25 that is pretty easy to do, I don't know about your engine.

 

[Alaska Mike]

If I lost the cat, I could easily run it out the side. If I ran it out the passenger side, I could keep the cat. I've never liked doing that, since it puts the exhaust in harms way under the frame and rocker panel.

 

[Yorker]

Ahh ok. so your engine's exhaust exits the passenger side of the engine?

 

[Alaska Mike]

Ahh ok. so your engine's exhaust exits the passenger side of the engine?

On my LHD vehicle, it exits the drivers side of the engine. However, if I did a 90 degree bend just behing the crossmember, I could gain a little length for a cat. Something I need to look at when I get to that stage.