Finally checked my surge tank

And replaced the fuel pump and filter at 239K miles.
The fuel pump was marked Lucas and all the lines were original, as was the strainer.
The filter was changed last in 2008.

And, they were all perfectly fine.
I see a lot of photos of horridly corroded surge tanks and strainers that are falling apart and lines that are rotting away, from cars with 1/4 the miles this one has. Lending further weight to my philosophy of
“drive the d%&m car”.

The surge tank while itself really, really clean inside did have a quarter cup of rust chips in the bottom that are no doubt from the primary tank. As expected for the age.
The strainer was perfectly intact and after cleaning tolerated moderate poking at the screen without tearing, so I reused it instead of the much smaller aftermarket replacement I had on hand.
I pumped out about 14 gallons prior to disassembly using the stock pump and it was still working well enough, though I’d heard it be overly loud a couple times this summer and with the miles I figured I’d change it before it died. The Bosch replacement ( the stock one was a Lucas marked pump with Bosch germany in small print as well) had screw terminals like every other European car instead of spade connectors (lol), easy enough to swap. Mind the polarity.

I had one scare. I pulled the surge tank and cleaned it in the parts washer, filling and dumping it to get all the rust bits out many times, finishing off with some carb and brake cleaner in and out so it’d not smell.
When first refilling the tank, I saw the surge tank was weeping around the spot-welded on flange that the lock ring goes into. Gaahh!!
But after wiping it off a few times and over the course of 15 minutes or so, it magically stopped weeping. My working theory is it was not fuel, but solvent that had seeped in externally being somehow forced out, or just gravity draining. I let it sit filled for a good long time and no more weep. Very relieved.

I did not try to use the drain plug, it was easy enough to just pull the tank once it was empty. It did look like there was a magnet on the drain plug. Almost as if they knew there would be ferrous metal debris in there…

Only other note is even after running the pump with the filter outlet plumbed into a can to the point where it was dribbling and sputtering, the first time I removed the hose off the pickup that feeds the pump a surprising amount of fuel came out. I hooked it back up and engaged the pump again for another ten minutes and it was dry the next time. Go figure.

Not an overly bad job all in all. Bit sore from sitting in the trunk, but hey…


as I have posted before I eliminated the surge tank… put in a wix filter in it’s place… no problems… wix 33299… it has 1/2" spigots and easy to install…

You can run without a surge tank on most anything, until you can’t. Sort of like a baffled oil pan ,most of us never need them but the lack of has killed a lot of motors.
Most people will likely never reach that “can’t” point, depending on the pickup point of the pump, driving condition, pump flow, etc, etc.
Not a bad way to go for a lightly driven streetcar. There are also some very small aftermarket fuel cells that could be put into place of the factory one. Good time to re-plumb with AN lines and such. The fuel system really is a little “busy” in these. But it’s 70’s tech, so hey.

A returnless fuel system would further simplify things but that would take some doing.

I feel your pain, I did this job a couple of summers ago and was amazed by the rust and crud that came out.
If so inclined , I don’t think there is a real problem with the original car set up. I just replaced the filter after cleaning out the surge tank. New filter and new gasket on the fitment on top of the tank. After all this was not touched for thirty years and the car kept running.
I also went out and bought a couple of cow magnets and put them at the bottom of the surge tank and the main tank near the connection to the surge tank in order to keep any future rust particles down without clogging any thing.
I’m almost guessing this might be a five year check maintenance job for replacing the filter.

It looked like the drain plug had a magnet on it, but it was woefully inadequate for what was in there. I’m sure my main tank will cause me no end of grief and money at some point. Good idea with the magnets though.

Have you ever pulled or refurbished / replaced the main tank yet?

Nope, nor will I until I absolutely have to lol…

My surge tank was checked when I thought I was having a heart attack, and they took every manner of test to find out what was going on. Turns out, it was gall stones.

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I had my tank lined by a shop that did farm tractor tank work… he had a device to hold it in various positions… it’s not too bad to get tank in and out… there are articles on this site explaining