A bit of digging showed the main purpose of the exercise on this car is zero emissions and all fuel system components are made of stainless steel.
It’s also stated that the pump is sealed inside the tank and is rated to 5 Bar. Not a big deal there.
It’s also stated that in the even of a pump or fuel filter failure the entire tank must be replaced.
A 7 grand fuel filter replacement should go over well with a customer…
That being said, if emissions testing is not an issue in the state I would certainly head for the modification tools and adapt that tank for a serviceable pump or mount one externally.
Many Euro cars used external fuel pumps and fuel accumulators for a lot of years with no issues.
Any external pump would need to be mounted about level with the bottom of the tank though but my preference would be a tank alteration. Either way, 7 grand it ain’t gonna get…
If a customer were to come to me with this situation, I would NOT cut a hole in the tank to install a pump, especially if the manufacturer said the tank must be replaced
That’s WAY too much liability to assume
I can only assume many of my pro colleagues would have a similar attitude
Mounting an external pump to bypass the in-tank unit is one thing
But cutting a hole, installing a different pump, and devising some concocted means of resealing it is an entirely different ball game
If it was my own car, I might sit on it awhile and talk to other owners, scour the internet for ideas, and so on
But there’s no way in H . . L I would do that cutting and resealing for a paying customer
If there was a legitimate company that made an extremely high quality modification kit, I might consider it
Switching to an external pump can be tricky. Many high-pressure fuel pumps are not self priming (i.e., cannot pull a vacuum without liquid in them), so you need a low pressure pump in the tank to feed the high-pressure pump outside the tank.
Yeah, with a lawyer behind every tree, even a professional “Cut & Paste” job would be very risky…Especially if the fuel tank(s) are mounted under the back seat…They don’t tell you about these things in the Car & Driver road tests…
Doubtful the external pump will work, it will have to draw enough fuel thru the dead pump to run the car. The old pump will act like a giant restriction. I also doubt you will find any shop willing to modify the tank liability is too high on something like this. There is the option of used tanks but they are also listed at$1500 plus. I would pursue it with BMW. I saw a few forum posts about installing the non SLEV tank but could not find out how it worked out for those that tried it.
I fully agree that there could be a liability issue involved but much could depend on how much risk the car owner and guy doing the work is prepared to assume. A signed, notarized waiver absolving the modifier of any liability is a possibility.
It’s also unclear whether the OP would be expecting someone else to do the mods or if they would personally be doing it.
If it were my car and for 7 grand it would get a Quadrajet conversion before I ponied up that much money…
Just my humble opinion, but this is idiocy in engineering and I understand why the BMW dealer wanted near 50 bucks a pop for spark plug wires for my BMW motorcycle back in the early 80s.
The wires were also over-engineered…
