MGB - fuel tank R, R & R

Today's post covers the Removal, Refresh and Re-install of the fuel tank. The tank was removed for safety concerns while welding in new floor pans. I discovered, though, that there was a tiny leak at the rear and I had concerns about the viability of the fuel level float/sensor.

Standard Safety Precautions
Like any job, block your wheels, put it up on jack stands if you can't work on it while it's on it's wheels. Since you're working with fuel, at the very least make sure your garage doors are open with a fan blowing on your work area or better yet do this job outside. Obviously, don't smoke or have your friends/kids/wife playing with a welder or blow torch while you're doing this. I'm not your mom, so if you choose to slide under your car without eye or face protection, that's entirely up to you. Personally, I like being able to see things like sunsets and my wife's face, so I wear at least safety glasses, if not a full face shield anytime I'm working on a car. Honestly, the number of times I brain myself on my car has me thinking about wearing a hardhat too.

Free Your Lines
Fuel tanks are all very similar: there's a big hose to get fuel in from the pump, a small hose to supply the engine with fuel and there are vents (at least one) on the top that have lines that lead up to the engine (after routing through charcoal or something) for inclusion into the air that the engine uses at combustion time. On fuel-injected vehicles, there is an additional line for a return from the engine. When the engine doesn't require all of the fuel that the system has pressurized, like when you're decelerating, the excess flows down that fuel line back into the tank. So, once you know what you're looking for, you need to remove them from your tank before you remove the tank itself. First, remove the vent lines. these may not be the easiest to get to, but they will definitely NOT have fuel in them, so you shouldn't need a pan. Make note of where the rubber hose came from when you set it aside. You'll want to cut a replacement that's the right diameter and length at install-time.

before

Now, grab a pan. This is gonna get messy. Hopefully, you knew this day was coming and you already ran the tank to as close to empty as you could before you got to this point. If you have a full tank, this will take a while. Lying under your fuel tank, consider the rubber hose leading out of it. The VW bus was "gravity fed", meaning that the outlet is at the lowest point of the tank. Gravity sent the fuel to the outlet. This is one of the biggest fire hazards in the bus. If the fuel line ruptures, the tank will empty through that outlet right on top of the passenger-side heater box and axle. In the MG, like most cars, the fuel is not gravity fed, rather the fuel is pulled from the tank by a pump. This means that in order to drain the tank you'll need to create suction. I guess you could wire the pump to run the fuel into a pan... Regardless, there is fuel in that supply line, so slide the pan under the connection where the rubber meets the metal line that runs to the front of the car. Remove the rubber line at that connection and allow the fuel to drain out of both the metal line and the rubber line into your pan. There shouldn't be much fuel in either.

trunk underside - before

Now the fun part. We are going to siphon out the fuel with a MityVac. Set your MityVac up so that there is the liquid catch-bottle between the hand-pump (vacuum creator) and the rubber line. Create vacuum until fuel is dripping into the catch bottle and then pinch the rubber line with a pair of pliers. Remove the rubber line from the MityVac catch-bottle, and point it at your catch pan. Hold the end of the rubber line below the lowest point of the tank (and into the pan) and remove the pliers. Fuel should pour from the line into your pan until either your pan overflows or the fuel level in your tank meets the top edge of the outlet inside the tank. Wrap the end of the hose with plastic wrap so it doesn't drip all over you during the drop step. If you have a drain for your tank, slide your pan under the drain and remove the drain plug. These tend to send fuel all over the place when the tank has a lot of fuel in it, so it's best to siphon as much as you can before you open the drain. Ask me how I know :)

Last, remove the filler hose. In the MGB, this was the easiest part. The filler hose runs from the rear next to the passenger tail light through the trunk and into the top of the fuel tank. It is secured with a simple, albeit big, hose clamp.

Unwired
Before you can drop the tank, disconnect the wires from the fuel level sender. Depending on the car, the fuel level could have both a signal wire and a ground -OR- it may only have a signal wire. This means that the sender gets it's voltage difference basis from a ground through the tank itself. If this is you, consider a means of improving that ground, especially if your fuel level gauge is a little flighty, like mine.

Tank Out
This is the fun, satisfying part. I put my ATV jack under my tank to support it while I removed the nuts and bolts. Since there will inevitably be some fuel left in the tank after siphoning, you don't want that weight bearing on the fasteners, and then have the tank suddenly drop when the last one comes free. Some tanks are held on with a pair of straps. My old Camaro was like that, and many older American cars are too. These come off with a couple of bolts. The MGB tank is held on with nuts/bolts around the outside lip where the top and bottom sections of the tank come together. In total, there were 9 fasteners: four along the one side, 3 along the other, 2 across the rear. I guess the engineers couldn't make up their minds and be consistent. The ones in the rear can be a little tricky to get to. Once out, the rear edge of the tank can get hung up above the bumper so tilt the front down first and slide forward.

Drain, Clean and Dry
Once on the ground, remove the fuel level sensor. On the MG, it is held on with a spin-on ring that lets go after a couple of taps with a hammer. Set the sensor aside for testing, and then drain the remainder of the fuel through either the fill hole or the fuel level sensor hole. Depending on how old the gas was, you may need to recycle what is now in your catch-pan. Mine was relatively fresh so I used it in my lawnmower.

At this point, I refer to my friends at Mac's Radiator. They cleaned, lined and painted the tank for the bus a few years ago, and I want the same treatment for the MGB. For about $300, your original tank is better than new, you don't have to pay oversized shipping, you know it will fit and best of all... its a genuine shipped-with-the-car original part. In the MGB case, you can no longer buy a true original. The aftermarket tanks generally don't have splash baffles (prevents the fuel from sloshing around when you corner), and some don't have vents. They aren't lined (so they may start rusting from the inside) and they are of inferior, thinner steel. Still, I did find one for $170 plus shipping that "are made with corrosion resistant Ni Terne steel to fight of rust and ethanol fuel". This is from a less-than-best distributor here in Oregon (poor return policy), British Parts Northwest, and again, it isn't lined. Part link here. Of course, good work isn't fast, so it will be a couple of weeks of waiting before I have it back, ready to install.

While your tank is at the radiator shop, test the fuel level sender. Rather than re-hash, here is a fantastic article for testing and calibrating the fuel sender and gauge. My float would not give a consistent reading below about 100ohm (or from a half tank to full tank), so it will be replaced.

Parts
The parts list is actually longer than I had anticipated. Looking at the picture above, the newer shaped tank is on the right. It bolts up directly under the trunk, so rather than having steel on steel, there are foam "straps" that fit between. There should also be a seal around the edge of the filler neck. Add the fuel-level sender. I also added in a new sender seal and locking ring. Of course, I'll be using all new 5/16" fasteners and rubber lines from the tank to vent and engine fuel-supply. Once assembled, everything related to the fuel tank and supply to the engine will be refreshed.

Placement Prep

trunk underside - after

So, the tank is out and off to the radiator shop. We're waiting for parts. Ugh. I hate the waiting part. To make the most of the delay, I grabbed my face shield, my angle grinder and a wire-wheel attachment and set to clean up the underside of the trunk. Before I got down to it, I shot the surface with Simple Green and a scrub brush. That's all it took. I hosed it off, and it didn't need any additional prep. I could have ground off the undercoating, but there was no need. So, I just shot it with some paint to help it last longer. Even though no one will ever see it, it sure looked pretty when it was done. I did a bunch of clean-up on the trunk floor and the rear bulkhead at this point as well. I'll post on that later, if I remember to.

Tank Prep
When the tank is returned from the radiator shop, it should have a protective coat of paint, but if your shop is anything like Mac's, they highly recommend a thicker, more protective coating. So, sand an edge into their paint, then prime, sand, wipe and paint with a suitable topcoat. Since this is not going to be seen, this doesn't need to be the expensive body paint, but something chip-resistant makes sense, since it will be exposed to the road. Once cured, install the level sender with the new seal, making sure the fuel pick-up tube is pointing toward to bottom of the tank.

after

If you got the new fastener pack, it includes little clip-on bits that act as an a-fixed nut on the tank for the loose bolts that are placed from the trunk. Be mindful to put the new ones where the old ones were removed. Not all of the mounting holes should have these clips. Some of the connections are with welded-in studs hanging down from the underside of the trunk so if you don't get the clips in the right holes, you won't be able to install. This is one of those "a picture is worth a thousand words" moments. See the blue tape in the picture for reference.

Since the steel tank sits up against a steel trunk floor, the MGB was originally outfitted with foam strips to set between. As you can see by the parts picture above, these foam strips run front to back. They are purchased as a roll and need to be cut-to-fit., It is very possible that you could save a few bucks and get basic home insulation strips at a big box store. The parts vendors assure me that the real deal are gasoline resistant, so the extra few dollars are worth it. Your choice. I bought the real parts since I was getting a bunch of other stuff anyway.

Last, set the foam collar around the fuel filler inlet. This needs to be in-place before the tank is installed.

Tank In

With new fasteners in hand, set the tank back on the ATV jack, roll it under the trunk and raise it close to where it will reside. Remember that the rear-end of the tank tends to hang-up, so tilt the tank so the rear end installs first. There are two studs on either side that are permanently attached to the trunk floor. Use these to center your tank, and lightly finger the nuts on (after the washers, of course). Now, you can drop the 5 loose bolts through the other holes in the trunk, making sure to include the large washers (first one nylon then one steel) between the bolt-head and the trunk floor. These will line-up with the clip-on bit/nut things. In my case, the clip-on nuts on the rear of the tank slipped on install so I had to poke at them with a long screwdriver to get them to line up with the holes. Take care as you tighten things back down, making sure that the foam strips do prevent steel-to-steel contact.

Re-Connections

the contrast between new and old

Using new rubber hose, re-connect the tank outlet with the steel fuel-feed line. Then re-connect the return line (if you have one), the vent lines and the big fuel hose. Last, reconnect the fuel level sender wire(s). Make sure you didn't leave anything disconnected, like the drain or one of the fuel-carrying lines. If you haven't looked at the hoses under the hood, now is the perfect time to do it. I found that the hoses near the tank were relatively new (PO replaced the fuel pump), but the lines under the hood were stiff and ready for replacement. After a final once over, put in some fuel, test fire the fuel pump a few times to prime the fuel line and you should be good to go.

That's it for today. I only got after the fuel system because I had to do some welding, but I'm glad I did. Rust hides. If you don't get into the little crevices, you won't see what's growing until it's too late. The top of the tank looked horrible, but once the rust was arrested, the remaining steel was thick enough to last another 40 years. As always, thanks for following along-

Tank's Giving

Okay, horrible pun.  Guilty.  Still, I hope you all had a pleasant ThanksGiving holiday.  For those blessed with a 4 day work-stoppage weekend, I hope you were able to make the most of it.  I was able to celebrate White Friday with a large group of fellow non-consumers.  I'll talk about that another time so I can talk through how to put a fuel tank back into an early bay-window bus today.

Clearance
Before you do anything, you need to verify that there's nothing between the rear hatch and the tank compartment.  This sounds obvious, but the tank is deeper than you may think, so you need a clear shot through.  The stock wiring harness shouldn't get in the way, but if you have any customization (like, oh, I don't know... a TDI engine instead of he flat-four), you may have some wire-dangle issues.  Solve those.  Zip-ties are your friend.  Also, if your stock engine is still in, you can slip the tank around it, but everything above the heads must come off first.  That includes the intake, carb (or FI), filters (air & fuel), etc.  Its actually easier just lowering it out of the way like I described in an earlier post.  The actual removal of the stock engine is very well covered in the Idot's Guide.  If the engine is on the shop floor, make sure you have at least 1/2 of the left-to-right space clear from the floor to ceiling of the tank compartment back to the rear hatch.

slide along right side and rotate into place

Vector
Steering the tank through the rear hatch and into place is an exercise in patience.  Enter this step knowing you will have to do it many times, and you will not be unpleasantly surprised with an entire afternoon lost to wrestling your tank in.  Before you start, set the foam seal back into position.  On my TDI-powered bus, I needed to raise the right side (using my BusDepot bus jack) so I could get past the engine on the floor.
I sent the left edge in first and routed it around the engine into place.  Get the tank partway into the tank compartment and attach the level sender wire and the ground wire.  Then, the tank can settle into place with wiggling.  Slide underneath and check that you can't see the foam seal.  If you can, you can try to move it with your fingers from below, or re-set the tank.  Neither are fun, but both work.  Using fingers from below is faster, though.  You can feel when the tank is settled into place.

Assembly
Now, you can start re-connecting things.  I did them in this order: fuel filler hose, fuel vent line, fuel return line (mine re-uses one of the original vent lines), fuel feed line.  As I mentioned in an earlier post, I replaced my fuel filler hose with a bent section of steel pipe from the muffler shop.  I was able to find the right size Viton hose at CarQuest, but only in straight sections.  So, I cut 2 3" collars from the hose, and I use them to abut the tank to the bent-pipe and from the bent-pipe to the filler on the side of the bus.

wire it up before final placement

Re-use your clamps only if they were in nearly-new condition.  Otherwise, they aren't that expensive, but its better that than have one fail and cause leaks.  It is a major pain swapping those clamps after everything is back in place.  Last, the hold-down straps are cinched into place.  This is a little challenging if the engine is in the engine bay, but on the floor.  Since I put a heating unit in my engine compartment, and ran the air hose forward along the left side, it really gets in the way.  Still, there's a washer and a 13mm nut (you need both).  Use a deep socket and put a vice grip on the strap so it doesn't torque as you tighten.

That's it for today.  We had a great White Friday, and I'll post about that soon, as well as the engine install headway.  Thanks for following along!

Tank redirection

The WestMarine tank arrived on Thursday. After a bunch of other distractions this weekend, I was able to get a few semi-interrupted hours to try to fit it into the bus. I found that it would not fit into the fuel tank bay. My measurements are correct, but the fuel tank bay is not square. In fact, its all kinds of lumpy which works great for the lumpy original tank, but is lousy for a flat bottom tank. So, I moved on to plan (b) or os this plan c or d?

I figured that I'll be running diesel or a biodiesel blend of some kind. These fuels are not explosive like gasoline is. Evidence: semi-trucks have their fuel tanks hanging under the doors out where everyone can see (or hit) them. The national safety folks and the collision testing people appear to be fine with that. So, I tried to fit the tank under the "rock-n-roll" bed (some call it a Z-bed - misnomer). The tank fits with a couple of inches to spare on top, but the fittings are a small problem. Once I removed the floor register in the center of the front wall (it was non-functional in my bus anyway), the power converter, and the driver-side lower bed support the tank could sit flat. I may need to remedy the support, but the power converter will move into the area where the fridge is. I don't use the fridge as a fridge anyway, so that whole thing will come out and go onto craigslist or theSamba.

Back to the tank. I had to cut down the fuel inlet to about a 1/2". That should provide enough space to put a 90* bend hose in without the seat bottom rubbing. I determined the route for the fuel fill line through the firewall, and started making the opening. I will need to route the tank vent back into the engine compartment too, so I'll be boring a hole for that. The outlet on the tank looks a little small, and the tank did not come with a male nipple, so I'll need to figure out what size it is and buy one at Lowes or Ace Hardware. I'll have to bore a hole for the engine fuel supply line too. For all of these openings, I found bits at Lowes to fortify the hole for the lines to pass through. I'll upload pictures once I take some :) The key here is to extend the opening so it isn't a thin steel hole that can work its way through a rubber (or even steel, given time) fuel line.

I will have to fab or purchase tank hold-downs. I know I can get them at WestMarine, but they're like $35. One last lingering concern: the fuel tank fill inlet is 1-1/4" and the filler at the flap on the bus is 2". I purchased a rubber adapter, but I don't know how it will fare with diesel fuel. One more thing to keep an eye on during routine maintenance efforts.

Hal will return next weekend to finish out the engine mounts. So, the fuel stuff on the engine compartment side needs to be done by then. Its another busy week of school, soccer practices and evening meetings, so it will be tight getting this done before Hal arrives on Sunday afternoon.

pictures:
top - plate on the top of the tank
middle - tank in-place under the rock-n-roll bed
bottom - fuel inlet measurement. Yes, it looks like 1-1/2", but the conduit I found that matches is 1-1/4"

Sunday Sweaty Sunday

Hal arrived shortly after noon on Sunday after making his rounds through the small VW event at Portland International Raceway (PIR). Considering the number of air-cooled (and water-cooled) Volksies in the Pacific Northwest it is surprising how poorly run and barely attended a VW meet is here. Of course, I didn't go, so I guess I'm part of the problem. To be fair, the one flier I saw was at a VW-only parts shop, and the flier didn't have specific event names or times on it. Anyway, he arrived ready to work, and we got to it relatively soon after he arrived.

Mount Brackets
Hal and I have been going around on how the engine would mount into the bus. When I started this project 2 years ago, I had planned to mount something to the sides of the block and route that to the frame rails. I'd thought about using hydraulic mounts or something along those lines. I had "Ed the Welder" even fab something (before I got the engine into the bus), but he didn't do the work as I had initially described (no rubber mounts, so the bus was gonna vibrate like a paint mixer), so that idea got tossed. I moved to the "we'll do it kinda like the stock way, with the big mount coming off the bracket that goes around the timing belt. Well, now we're back to the brackets on the sides. That's how the Aussies do it. That's how the Brit's do it, so that's how we'll do it here in the colonies. Hal was able to make some head way on a stock mustache bar by extending the frame rail brackets by a couple of inches. It doesn't sound like much, but that was a few hours of welding and grinding to get to that point. With the hotter and muggier Summer we've been having, we had to take many breaks. During one of the breaks, we took a run to Home Despot for a drill bit that we fried. During another we hit the web searching for suitable rubber mounts. I regret selling that pair I had in hand 2 years ago. They may not have been perfect, but they were in hand. Anyway, we're going to try a Dodge truck engine mount. I'll be picking up a couple this week. We only need one to verify it, but I can just as easily return 2 as 1, and if we like it, I'd rather not make that stop twice.

Keep on tanking
Around helping Hal at various points and helping clear construction debris from inside my son's room, I was able to get some more traction on the fuel tank. The original fuel filler hose for the 1972 VW Bus is no-longer-available (NLA). So, in order to replace a failing (or 30+ year old) hose, you need to be creative. I took the old pipe down to the muffler shop around the corner and had them bend a pipe along the same contour in the same inner diameter. Unfortunately, exhaust pipe is much thicker than the old fuel filler hose. This became important, but for a few bucks ($10), I have a pipe that will last a long time. With my angle grinder, I cut off enough of the steel pipe so it would fit between the tank and the filler pipe with an inch on space between. Last week, I picked up a 2-1/4" Gates fuel-filler hose (pn 23976) at CarQuest. This was the stock diameter and the widest diameter they had, but I could only get the rubber hose one through much heavy sweating and torquing with a flat-bladed screwdriver. Once that puppy got on, there was no getting it off without considerable effort. I left about 2" of rubber hose sticking off the end of the steel, and had at least 1/2" on the bent exhaust pipe. Now came the fun part. Leaning over the back of the bus (on my toes), I twisted the rubber first onto the fuel filler and then onto the fuel tank. After tightening it down with a pair of new hose clamps, the fuel filler is now completed.
Remaining for fuel system:
(1) finding a location for the fuel filter
(2) mounting filter
(3) replacing fuel lines from tank to filter, including a "T" for the return line, and a clear cheap primary filter
(4) replacing injector lines
All of that will wait for now. I'll be switching to the vacuum system next. I will have to get a brake-booster capable electric pump, start mounting vacuum valves, replacing vacuum lines, etc. Hopefully, that won't take too terribly long.

pictures:
top - a closer look at the extension on the right-side frame rail bracket.
bottom - wider look at the same bracket showing how is sits under the engine.

project creep

Well, the weekend after the election was full of painting and other things, so the bus slid off the radar entirely. I did want to quickly follow up on that neighbor badness post, though. My wife had an unexpected encounter with him when she returned from walking the dog, and asked him directly if he called the cops on us. He sheepishly admitted it and apologized once she explained things. Simply put, we believe in free speech. We are peaceful people that wouldn't do anything to their property and over the years we've lived across the street we have never done anything to make them believe otherwise. After this was plainly explained, its over. Ahh.. I hope this puts this whole nasty thing to bed.

I am almost finished with the living room stuff. The beams and posts took 4 coats of paint - 2 primer and 2 top coat before they looked good. Since I was anticipating half as many coats, it took a lot longer than expected. But, the can lights are in, so the living room is done. I just have to switch out the lights in the front hall, and my domestic projects for the Fall are completed. Of course, the leaves don't rake themselves......

Around the painting in the living room and front hall, I was able to get some small things taken care of. I bought a section of pipe and had it bent by the guys at Meineke. I've measured where I need to make the cuts to keep it at length (less 1/4" at each end). I didn't have time to cut it yet, so its not in the bus. I was able to get a 5/16" fuel line nipple at NAPA and open up the tank nut with a hand drill to fit the nipple. Then, the nut threaded onto the tank. This leaves the return line as the last piece to be resolved within the fuel system. I'm not convinced I need to actually put a port in the fuel filler pipe/line. I should be able to Tee into the fuel supply line, but if that were the preferred method, VW would have done that. So, I'll probably drill a port into the pipe I got from Meineke. Depending on time and available light, I'll be working on this in parallel with the engine install.

Anyway, not much in terms of news and no pictures. My next post will revolve around the install of the engine. I've decided the weather will not hold up much longer, so its time to move it all indoors. Wish me luck--

onward

Honestly, this post is just to move that last one off the top of the stack. Now that the election is over, the vehemence that I felt last Sunday feels a week away. On the project side, I should be completing my living room efforts by Saturday night, so, if the weather works out, I may be able to get the engine in Sunday. I still need to resolve a few things, but I think I could even resolve those things after the fact.

1 - fuel filler hose
The original hose is just that: original. That means its almost 40 years old. I don't expect that rubber to stand up to any more use, much less the diesel blends that have biodiesel (BD) in them. BD eats old-style rubber quickly. I think it eats the "biodiesel-ready" rubber too, but thereis little evidence on either side of that debate.
My plan is to take the old rubber hose over to a muffler shop and have them cut/bend me a pipe in the same shape and length, save for about 1/4" on each end. Then, I'll use the rubber hose as a source of joiners between the new pipe and the old connections. That should last a while.

2 - fuel return port
The original fuel tank doesn't have a place to route fuel overflow back into the tank. Since the 1972 VW bus was a carburated engine, there wasn't a fuel rail, or any overflow fuel to route back to the tank. I could have bought a later bus tank, but there was nothing wrong with the original, and I'd rather leave as much alone as I can. Yes, I know putting a water-cooled diesel engine in kind of runs against that. Still, the less I change, the fewer decisions I have to make. Like, does a newer tank fit in the tank bay?
My solution idea is to put a port into the fuel filler pipe that I will be having fab'd by the muffler guys. It seems pretty simple to me: bore a hole in, thread a nipple into the hole, attach the return line. I need the pip first, then the nipple, but this shoudl be a pretty easy step.

3 - starter
The original starter will fit into the original opening on the transaxle. Unfortunately, it doesn't provide enough torque to start the engine. There are vendors that are willnig to sell me a "hi-torque" starter that will directly fit. Unfortunately, these "hi-torque" starters are built like crap and are known to fail soon after the check clears. The vanagon TDI folks use a TDI starter with an adapter constructed by "Westy Ventures". From my findings, though, the vanagon starter (SR87 fitting a 091 and 091/1 transaxle) has an output shaft about 1/2" longer than the old 002 transaxle starter (SR15, SR17). So, if I were to use the adapter, it would fit in the starter hole, but the gears would overshoot the flywheel by 1/2". So, I'll either need an adapter for the adapter or a custom adapter right off. I'm leaning towards a custom adapter, but I'll need to find someone capable of doing it. I have a mock-up made out of wood, so that fabrication would be a pretty easy job for someone with the tools.

I don't really need any of these bits to get the engine slammed in. In fact, I can address all of these in the warm comforts of my garage after the engine is in. I would, however, like to get the fuel filler pipe done first. It is so much easier getting that pipe on without an engine to climb over. I'll try to remember to bring the gose with my to work tomorrow. Hopefully, I'll be able to find a local-to-my-work place that will cut and bend while I wait.

More later...