Petrol Pump repair/replace - 1937 12 P2

[P27]

I've been asked to repair or replace the petrol pump on a 1937 P2, because it is apparently leaking petrol into the sump oil.
I've found a vid. here: https://www.youtube.com/watch?v=gFpMBkJHs0A&t=40s
Is this similar/appropriate to the P2?

Does anyone have the pump part number?
And advice where to get a replacement or a seal kit?

Any help much appreciated.

[Willem]

I rebuilt the fuel pump on my 1936 Rover 12 with this: https://www.flexolite.co.uk/products/fp ... ent-to-bd1
Yours might be different, I took mine apart and compared the parts to the various ones they have on their website.
This worked for me but no doubt someone with much more experience will be along before too long..
Willem

[SHyslop]

Willem is right, Flexolite have all the right bits. You might just need a diaphragm from the description you have given but read on..... If you haven't worked on one of these before, things to know:

There are two separate types of valves. Older pump tops have paxolin valves (check the size , two widths available) with separate springs. Later pumps have caged valves which need prized out of the cover and driven in whereas the first type have three small countersunk screws to hold the valve cage in. Take a note of their orientation before removing, one goes up and one goes down. I have found cheap reproduction valves to be difficult to seal in the pump tops compared to originals or more faithful copies. However, you may not need these if they are in good order. Your pump could have caged valves but over the years people can change them depending on what was to hand. The video you have is of the type of pump fitted in 1934 so yours should be the more modern type but remember that , over the years, many eager hands could have been over your car and the pump could be (much) newer than the car - or not!

It is essential to check the seal of the pump top both at the cover seal and also the washer on the top bolt. These both must be airtight and remain so. The top screw can be a problem if the thread on the pump top has been overtightened and stripped.

Make sure the pump chamber under the filter is cleaned out while you have everything apart. If you want to be as safe as possible, once you've identified exactly which model you need parts for, a repair kit may be the most financially advantageous and then you will have everything you need to hand.

Once sorted, these pumps should give reliable service for thousands of miles, the only occasional maintenance being to check that the top bolt remains secure as they have a tendency to slacken off then people give these pumps a bad name when they don't work as they should.

[P27]

Thank you both, a wealth of info.
I don't get to see the car for 2 wks, but will report back then.

[P27]

I've removed the AC pump and it's a Type U - so has the original has been replaced at some time?

Are Type U OK for this engine - The engine number is: 811721*. (e.g. the 'throw' of the cam/lever is not too large), or the spring pressure too great?

Are originals pumps still obtainable? Or should we repair the existing?
https://www.flexolite.co.uk/products/fp ... ent-to-bd2
Another SU forum (austin seven) mentions part Nos on the pump, and on the arm/lever - where should I look?

Any other info on this engine 811721 gratefully accepted.

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[SHyslop]

It'll probably have been replaced. The delivery pressure for these should be 1 3/4 lbs. This is the lowest for an AC pump and they can go up to 5 lbs(Buick) but probably the most common ones, for an Austin , are 2 1/4lbs.The spring under the diaphragm controls this. There's usually a number on the arm but these Rover pumps have a somewhat different size and shape of actuating arm to many of the others. The hard part to know is whether this pump will have been fitted as a "new from AC" Rover specific pump or whether it has been for something else and someone has swapped the necessary bits over to "Roverise" it. I would say it has been pretty common practice in recent years to do the latter because this design of pump specifically for these cars has been obsolete for quite a long time.

You can test the pressure with a kit AC used to make but if you think the car was working at some time in the past with what is on it then there's no reason why it shouldn't do so again. The problem with newer manufacture pumps which look superficially similar is that the threads for the pipe fittings are different now and unless you have ready access to a selection of threaded couplings it can be an awkward job marrying Enots fittings to metric or SAE depending on the date of manufacture.

It would be worthwhile blowing down the pipe to the tank and making sure that the pipes are unobstructed. I'm not sure when they started fitting a gauze to the pick up pipe but if there isn't one, watch out for largish pieces of tank debris being sucked to the intake.