I don’t believe that was me. The line from the pump to the Webers is steel braided
ah, it was to the pump, from the chassis line.
So nylon (50 yr old) to steel to nylon (50 yr old) to pump to braided to carbs.
Well, I had some time today to open up the fuel pump.
A few things I’ve noticed. It looks like the FP has been rebuilt in the past and the internal components actually look ok.
Biggest concern is what looks like Pitting in the casting (Photo attached).
I’m wondering if this was not allowing a good seal between the glass bowl and the casting, thus the leaks.
Thoughts anyone?
It also looks like the valves have been previously replaced.
Does this Spindle Seal look like it is in good enough condition to stay or should I replace as a matter of course (I’d have to find and purchase one)?
If the spindle seal is still flexible, I’d leave it in.
I also noticed that the spring in the lever is very floppy and not acting as a spring at all. I’m thinking that the tiny rivet that attaches it is working loose.
That’s my inclination
I have the Fuel pump back together.
The small spindle retaining clips were a royal pain to re-stake.
Moved on to trying to measure the fuel pressure from the pump currently on the car. Ran into an immediate problem with the connection threads. Both the current pump on the car and the AC refurbished original have 1/2 inch-18 threads. The fuel pressure gauge has 1/2-20 and won’t connect!
Paul
@steve lyle ,
Did you have any issues connecting your gauge to the fuel pump?
The thread pitch seems to be an issue for me
I mis-measured. The fuel pump fitting is 1/2inch-20 UNC
I put a barb fitting on the gauge. Then fuel hose on that. Slipped the hose over the stub pipe that’s connected to the pump output with a compression fitting and clamped it on with a jubilee clamp.
Paul, if you need a stub fitting for the pump, I"m pretty sure I have one. Let me know.
Thank you Greg for your kind offer. As it happens, yesterday I was able to find a threaded to Barb fitting from a local car parts store.
Part “Dorman Fuel Line Adapter 785-402D” ( https://www.dormanproducts.com/p-35879-785-402d.aspx ) has the correct 1/2inch-20 thread fitting.
Thanks Steve, that’s more or less what I’ve ended up doing too.
Paul.
Well, I just measured the pressure from the currently attached Fuel Pump…it’s a whopping 10PSI no wonder I have a flooding issue!
I’m using a new Pressure Gauge from Harbor Freight ( https://www.harborfreight.com/fuel-pump-and-vacuum-tester-62637.html ), but I can’t rule out it’s calibration being off. It does have a pretty high review score though.
I believe the pump that is currently on the car is a pump that may have been supplied a few years ago from RDEnt. It has the priming lever. I can’t be definitive because it was a garage that obtained and fitted it, not me.
Irrespective 10PSI is off the chart. Now on to replacing with the refurbed original I have.
Hi Paul,
So pleased you went the extra mile to prove to yourself what I have been preaching to anyone I come in contact with for some time now that the all metal mechanical fuel pumps that most of the usual suppliers are selling are just not suitable for our cars!
Delivering 10psi is totally unsuitable and will cause flooding no matter what carburettors anyone has fitted…
Note:-There are now also new imitation AC chinese or wherever glass bowl pumps on the market and being sold by Lotus suppliers that also deliver a totally unsuitable fuel pressure!
Only the original AC pump as spec’d by Lotus for the Twink will do.
Anyway…It seems you are getting there 
Alan.
Thanks Alan,
What if anything would you normally use on the paper gasket between the fuel pump and the Spacer block?
Paul
This can be an area for an oil leak!
Check if the face of the pump is perfectly flat?..If not, carefully file the face flat.
Then I would lightly smear the gasket with RVT Silicone.
Alan
New Fuel pump problem
Well this is turning into quite the Saga!
I went to test fit the refurbished AC fuel pump and the fuel pump wont fit over the studs!
Thinking it was just an angle/positioning problem, I unscrewed the studs and then checked to make sure the fit in the FP holes…they’re too fat by about a 1/32 or so.
I’m guessing that when the garage changed out the Fuel Pump and fitted the replacement, they must have also changed the studs too
I’m now scratching my head trying to decide what my next step should be. Are there slimmer studs out there?
Any thoughts from the knowledgeable???
Paul
On checking the Workshop manual, it looks like the Fuel Pump should be attached to the Engine with Hex bolts. Mine has studs!
I guess I need to get two bolts. Any specs on the length+width? I can determine the thread, but what is the standard length for these?
The studs are 5/16" diameter which would seem a reasonable size, but they were just slightly too fat (by a hair ~ maybe a 32nd or 64th or thereabouts)
I’ve placed one of the studs on the assembly page here.
Thanks
Paul.
Do you have Buckland’s book? As I recall there is a section with all bolt sizes, though I don’t remember if this one is called out.