MGB Driving: Windshield Washer ASS-U-ME

This is a story about re-installing the windshield washers and how to NOT assume that things from the past are correct, because you might make an “ass” out of “u” and “me”. This was the case.

The previous owner removed the windshield washer and I assume it was because it was not working and also that he could not get it to work. But, not only did he remove the windshield washer he also cut the hose right at the firewall between two metal firewalls. The complete assembly was also removed and the previous owner gave it to me with the car.

So the first thing I did was order the proper size hose at $ 0.80/Foot. I ordered 10 Feet to be safe.

I then sanded the bottle holder and painted it. I scrubbed the bottle with cleaner to get it white again.

Now, before I go any further, notice the picture of the pump installed on the left side of the holder in the picture. Notice how it is installed vertically? Let that picture burn into your mind.

I re-assembled everything. I could not join the tubing at the firewall, because I just could not get to it, so I pulled it through from underneath the dash and cut off the painted area (the part sticking through the firewall). I was able to feed the tubing through the hole from the engine bay into the under dash. I put a rubber grommet but I have yet being able to install it on the hole. That I will attempt another day. It is just hanging next to the firewall hole at the moment.

I then ran the tubing over the heater box and through the clamp to the windshield washer pump that I just installed. I connected the tubing and the original electrical wires were still there, so I plugged it in. I then removed the two tiny chrome nozzles on top of the hood and cleaned them out using tools for cleaning carburetors. Tiny metal rods that could fit in the hole and clean out old wax and dirt that had blocked them.

I got in the car and I pressed the washer and nothing happened. So I removed the pump, disassembled it and used an electrical contact cleaner and some Teflon spray and I got everything working again. I re-assembled the pump and tried it. It was working but no spray was coming out. I sprayed and sprayed and sprayed some more, but nothing came out. The fact is I sprayed so much without any fluid going through I burnt and destroyed the little rubber impellor inside the pump, as I discovered when I took it apart a second time.

So I started to search online for a new pump and I found what looked to be a very similar pump at NAPA for $ 20.00. I ordered it and picked it up a few hours later.

I installed the new pump and turned on the car, pushed the sprayer and the pump was worked but nothing came out. This time I resisted the temptation to keep pushing and burn yet a second rubber propeller.

I sat in the car for a bit and began to think. I remember seeing that tiny 1" x 1" folder paper behind the pump in the packaging. You know the one, where you need to unfold it multiple times to see the big picture. I got out of my car and retrieved it, quickly unfolded and unfolded some more until there it was. To my shock, the mounting height and positional direction of the pump depends on whether your bottle feeds from the bottom or by a tubing on top, like in the MGB. The directions showed the pump mounted horizontally rather than vertically for my bottle type. Don't ask my why. I assume it has to do with something Sir Isaac Newton and an apple. So I removed the pump and used one of the two bolts to mount it horizontally. I got in the car and voila, it worked like a charm.

Hence the title of this blog post. I assumed it was mounted correctly because that is how it was. I now know that if I had mounted the pump that I repaired horizontally, it too would have worked fine. If ever you need to re-install a windshield washer pump, read the instructions or remember this post.