Engine Starting Issues

[Psevins]

I was just thinking about trying that then thought about leaving the dashpots off to see if I could visualize and fuel coming into that part of the body. Not sure if that's a good idea or not. When I was cleaning them with the carb cleaner and compressed air the jets would refill with a small amount of fuel so that seems to be ok to me.

I got stuck replacing the coil this morning which took longer than it should (everything was seized) then decided to paint the bracket while I had it out now I'm waiting on that to dry before reassembling that part.

[redroadster]

While it's apart. Check the ohms between the coil ground and batt ground , with the points closed

[Psevins]

Good news everybody! Either my excessive use of carb cleaner and air worked or the new coil did the trick (or a healthy bit of both) and she started! Sounds wonderfull at idle. a little doggy when pressed with gas pedal but not to bad.

[Psevins]

Good news was short lived. I believe I have a bad fuel pump now as I'm no longer getting fuel to anyplace (replaced the engine bay lines with new and they are staying dry). I blew the line back to the tank out with compressed air too. Ordering a rebuild kit Monday.

Hopefully that solves this problem.

[Psevins]

Rebuilt the fuel pump and it still won't pump fuel. Tried running from a small container of gas and still wouldn't work. I'm going to stick an electric one on it to further test.

[greydog]

Wait... are you. Sure you have fuel to the pump? When you pulled the hose from the tank, did a little fuel run out?
Dan

[Psevins]

I tried pumping from the proper fuel line from the tank and got no fuel to the carb (I installed a temporary clear filter right at the carb to visualize the fuel). Then tried pumping from a tank of gas on the ground thinking maybe my main line was clogged. Still no gas flowing. I'm using new rubber lines in the engine bay (I had just changed them when the fuel pump seemed to die). I've checked all my new lines too for blockages just in case.

No fuel comes out anywhere.

[DAC21]

Rebuilt the fuel pump and it still won't pump fuel. Tried running from a small container of gas and still wouldn't work. I'm going to stick an electric one on it to further test.

What was replaced on your rebuild? Diaphragm only?, or new valves and upper Washers and Gaskets as well?

[Psevins]

First just the main diaphragm, didn't work then I got inventive (in desperate) I used the diaphragm out of a new fuel pump for a 510 since I was having difficulty sourcing just a rebuild kit (the whole assembly was $18 if I recall). Once that didn't work I looked at the little valves in the top. On my original those come out but on the 510 they do not. My solution was to take the top portion of the 510 fuel pump and attach it to my old fuel pump. Everything lines up and it screwed right down. A bit of a hodge podge but I figure it should work. Perhaps not though.

[Psevins]

I should also point out that I haven't actually taken the pump off the block, just working from the top down.

[DAC21]

First just the main diaphragm, didn't work then I got inventive (in desperate) I used the diaphragm out of a new fuel pump for a 510 since I was having difficulty sourcing just a rebuild kit (the whole assembly was $18 if I recall). Once that didn't work I looked at the little valves in the top. On my original those come out but on the 510 they do not. My solution was to take the top portion of the 510 fuel pump and attach it to my old fuel pump. Everything lines up and it screwed right down. A bit of a hodge podge but I figure it should work. Perhaps not though.

Yeah that could be the issue. Not the same Fuel Valve, Diaphragm or upper chamber Gasket numbers when comparing OEM part numbers for the Roadster vs 510 fuel pumps. It may fit but that may not be enough to make it work.

[Psevins]

I think the diaphragm will work (read about it elsewhere) plus it is physically identical. The valves look the same but I can't verify since they don't come out.

I suppose I didn't try swapping the hoses around in case the pump markings are wrong (inlet and outlet).

[Psevins]

Temporarily hooked up the electric pump and fuel is flowing. The new problem is it won't stay running longer than five seconds and cuts off. I'm not too worried at this stage since I've got a whole frame swap about to start but I would like to get it running solid again before the next tasks. The only thing that has changed from prior to fuel pump failure is I removed and capped the smog pipe outlets on the head.

[redroadster]

Is the fuel pump hooked wired to the regulator output/ fuel pump control unit ? Maybe it has this 5 sec timer ,that it needs input from the alt to keep going
Because it needs to be cut off if the alt stops , like in a wreck where the ign is not turned off and a line broke ?
So the F pump does not keep pumping fuel
I

[Psevins]

That's the eventual plan, right now it's not going anywhere. I'm just running it to test fire the engine . I've got an inertia safety switch on the way.