Fuel pump stopped

After many years of reliable use my fuel pump stopped. I went to start the car today and I thought it pumped up as usual but the car wouldn’t start. Checked the filters and all were dry. Test light confirms power at the plug on the pump, and ground is good. When I put the test light into the wire and connect the clamp to the pump it doesn’t light, which makes me think there’s a loss of electrical connection inside the pump. Gas tank is 1/2 full. Is there a way to take apart the pump to fix this? Thanks. Here’s the pump in question.

Have you tried tapping the points end to see if it fires up?

Likely the points (if not an electronic type) have gone bad. They can be cleaned with emery paper but it is usually only a temporary fix. New point sets are commonly available but it is a bit of a fiddly job to change them AND get the adjustment correct so the rocker assembly flips over properly each stroke. Best to test off the car with a spare battery as a power source.

I’m not sure if this one is electronic or not. How would I tell that from the picture? Is there a schematic somewhere? Not sure what you mean by the points end. I whacked all over it with a screwdriver… no change.

Correct me if I am wrong but it sounds to me like you heard the pump like always when you turned on the key and then the car would not start and the filters were dry. If that is the case you need to run the discharge hose into a suitable container and check to see if the pump is really dead. If it pumps then you need to look for another reason for the filters to be dry. If I have misunderstood your first post just disregard this.

You read right, I THINK I heard it pump… but I’ve since tried it a few more times and it doesn’t click at all, there’s no sound or anything so I’m convinced it’s dead. Not sure what the discharge hose is? There are only two hoses, one in from the tank and one out to the front.

Looking at the pump I think the top is the inlet. I would just pull the pump and remove the black cap and have a play with the points with emery as has been suggested. Nothing to lose at this junction (I was going to use point but thought better of it :slight_smile: )

Discharge hose is the one up to the carburetors.

Update, cleaned the points, didn’t need to, pump works fine. The fuel isn’t getting into the carbs. I’m about to pull the in line filter just before the carbs but my gut is its a stuck float issue, though I’ve just whacked both floats with screwdriver, no luck freeing them up.

There might be a dud length of hose somewhere. Can grow internally until hole closes over. Paul

There is also a filter in the tank, one in each carb float bowl inlet banjo, and one inside the pump.
I see the word OUT on the top so that is the discharge hose going to the carbs. You could pull off the top hose and run a long hose to a gas can and see if it will pump gas to the can.
Yes, pumps can be rebuilt, Moss and others sell the parts, and I’ve done at least a dozen with an electronic transistor conversion so the points last forever.
http://www.jag-lovers.org/snaps/snap_view.php3?id=1205939829
http://www.jag-lovers.org/snaps/snap_view.php3?id=1043639033

OK Update. Problem resolved. Fuel was actually pumping into the carbs but something funky was happening with the auxiliary carb. The needle was getting stuck open … which for some reason was making the engine not start. Once I noticed it, pulled that needle up, and engine runs as normal. ::sigh:: Thanks for all the replies, I now know how to troubleshoot the fuel pump!

Always good to carry a spare purolator/facet pump available at most auto parts stores. You don’t want to get stranded!

Gerard

Nothing but trouble them SU fuel pumps , I had to splash out £70 on a new one a few years back , 52 years is just not good enough :rofl:

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That one beauty of having an ‘S’ :slight_smile: