FUEL PUMP

[bmcecosse]

Mechanical pump works well - does your block have the access plate to it a mech pump?

[David W.]

I have the blanking plate.
I bought a mechanical and the spacer a while ago in anticipation. I'm going to have a fuel system week as soon as my new sender arrives. I'm going to clean and seal the tank with the POR15 kit.
I'll probably work on the SU pump later when I have nothing to do. Is there any particular value or type capacitor I should use?
What about a distributor condenser between the terminal and ground?

[Alec]

Hello David,

simply go to Burlen (Link in an earlier post) to get the correct item, you'll need a new cover anyway. It is to extend the life of the points (some versions use a diode instead, but that makes them polarity conscious) rather than radio interference suppression.
A point about mechanical pumps is that on cars used infrequently, they tend to need more cranking to start as the pump first has to fill the carburettor, with an electric pump, just switch on and wait for the pump to stop ticking. My Scimitar is bad for that and many owners fit an electric pump purely to avoid excessive cranking to start. (Compounded by the small battery Reliant chose and the limited space precluding fitting a larger one)

Alec

[bmcecosse]

Ahh - but the cranking gets oil round the bearings before the engine fires up - so overall a good thing!

[JOWETTJAVELIN]

Hell that is some overheating!

Note that a camshaft-driven mechanical pump can be fitted as an alternative to the electric - see the blanking plate on the engine block.

[bmcecosse]

But not ALL engine blocks......

[David W.]

Here is the latest update:
That electric pump in the third picture leaks! Out it came.
I reassembled the SU pump after fitting a small capacitor that I had clipped from a printed circuit board. I had cleaned out a lot of trash from the inlet. I'm going to schedule my fuel tank cleaning and lining project sooner than later.
The rubber sealing rings on the inlet and outlet valves in the SU pump had deteriorated greatly in just a few months. I presume from the alcohol in the fuel. Does anyone have a source for impervious seals?
I'm still inclined to go with the mechanical pump, especially after seeing the seals.

Now, to the hypothetical:
If one was to install an electric pump in addition to the mechanical, would it be installed in parallel or series?
If series, before or after the mechanical pump?
The electric pump would be used theoretically to prime for starting, or emergency use if the mechanical fails. It would be wired with a SPDT switch that has ON-OFF-Momentary positions.

[JOWETTJAVELIN]

In my mind there is no question: install the mechanical pump and forget the electric, if you are having so many problems with it.

My Allegro has a mechanical pump and fires almost instantly. If you want to keep both then I would suggest an off-take from the pipe where it emerges at the bulkhead, with the pipe pointing directly to the pump to be used most of the time and the off-take going at an angle to the auxiliary.

I cannot understand why the electric pump is giving so many problems; they do run happily for decades as has been said.

[David W.]

I'm starting the POR15 process for cleaning and sealing my fuel tank. so far, I have the tank out and flushed with water.
Can anyone reassure me that I'm not likely to seal up the intake screen?
David

[bmcecosse]

No - I think it is highly likely to seal the screen......

[David W.]

Well, it's too late now.
The sealer is only a half pint, and the viscosity of motor oil. It is possible to slosh it around carefully and coat all the surfaces. It is possible to move the filter around a little with the suction tube. I should have propped it up off the floor of the tank. some of the sealer got onto the screen.
I blasted it through the suction tube with brake cleaner. It appears to have plenty of penetration of the screen. I don't know what effect the cleaner will have on the cure of the sealer.
I got lots of trash out of the tank through the drain. The POR15 cleaning preparation didn't leave a shiny tank inside, but brought out a lot more junk.
I don't have any leaks in the tank, so the sealer doesn't have to perform that function. I want it to hold the remaining trash in place, which I think it will do well, So I'm not too worried about the dilution effect of the brake cleaner (which evaporates pretty quickly anyway.)
now, following directions, I have to wait 4 days to put any gas in the tank.
David

[David W.]

Just an update.
the tank cleaning and sealing went very well. After two tanks of gas, the fuel filter is still very clean. I'm impressed with the POR15 system.