hard starting

[Lotus Stu]

My '72 sprint starts nicely day to day, except when it sits a week or more without being turned over. Then, off come the Weber covers and in go some fuel to prime. Then it starts. Using an original mechanical fuel pump. Suggestions for a cure?

[rgh0]

electric fuel pump

[billwill]

This has been discussed on this forum many many times.

Read though some of these:

http://www.lotuselan.net/cgi-bin/search ... oom_sort=0

[alan.barker]

I suggest you look at past posts about this which are many
Alan

[gjz30075]

I suppose it depends on how long you're willing to crank it. My Sprint, with Webers, can sit a
month or so, but it'll start after about a minute of actual cranking. I'll crank it for about 15 seconds
at a time. I'll get oil pressure before even a cough. I'll keep pumping the accelerator, knowing
the chamber is filling and eventually it'll start.
Knock on wood

I'm willing to do this rather than the somewhat messy task of filling the float bowl from the cover.

Electric pump will solve all this, too.

[Lotus Stu]

Thanks for the advice and cheering. I had read the prior posted advice, so I feel quite at home with the majority who have experienced similar starting issues. Nonetheless, great motoring fun in 0189K.

[denicholls2]

My '72 sprint starts nicely day to day, except when it sits a week or more without being turned over. Then, off come the Weber covers and in go some fuel to prime. Then it starts. Using an original mechanical fuel pump. Suggestions for a cure?

Don't let it sit for a week or more. Drive it.

[Bigbaldybloke]

My car has been off the road for 35 years, during the rebuild I fitted an electric fuel pump. I recently installed the dash and most of the wiring and put a couple of litres of fuel in the new tank. I turned the ignition on to the sound of the pump frantically pumping away, when the note changed after a few seconds I pumped the accelerator pedal and turned the key and it fired immediately. No one was more surprised than me as I hadn?t even set the timing properly just roughly set it.
So I can recommend an electric pump, but one warning note, I fitted mine in the engine compartment bolted directly to the body under the carbs just above the steering column. It makes one helluva noise, the whole footwell seems to reverberate, I?m going to have to re position it onto some sort of insulated mounting.

[nigelrbfurness]

I use a piece of thick fabric insert rubber cut form a truck mudflap (Ebay) as an insulator for electric fuel pumps, you can drill it in a pillar drill with care(slow speed) and bolt the pump body through it.

[Bigbaldybloke]

Thanks, sounds like a good practical solution, I think I?ve got an old mud flap somewhere in the garage

[mbell]

I just spent a few dollars on a suitable exhaust mount bobbin for mine. On my +2 its mounted above the foot well. You can hear it with the engine off but not when it's running. Kind of useful to hear it as the change in tone tells you once the float blows are full and your good to start the engine.

[Keith Scarfe]

There was also the idea of fitting a hand squeezable thing in the boot to prime the carbs. I can't find that now. Does any one remember that? Have one fitted? Maybe have a link to somewhere to buy one (uk)? Would be a lot easier to fit than an elec pump.

[69S4]

I just spent a few dollars on a suitable exhaust mount bobbin for mine. On my +2 its mounted above the foot well. You can hear it with the engine off but not when it's running. Kind of useful to hear it as the change in tone tells you once the float blows are full and your good to start the engine.

Exactly the same on my S4, bobbin mounted and in the boot. You can hear the pump noise change when the float bowls are full and if it's been left for a few weeks it can take longer than you'd think to fill the bowls. I fitted the pump at least twenty five years ago and its been totally fault free.

On a few of my old motorcycles, if they're left for a week or two they won't start at all unless the float bowls are drained and filled with fresh fuel. They then start instantly. Some carburettor designs seem to be more prone to this than others - a couple of the other bikes don't have the problem and still fire up after six months or a year.

On the bikes filling them isn't a problem as the carbs are gravity fed but it's why that happens that's the puzzle. My guess was / is that the more volatile components in the fuel can evaporate from the float bowl leaving behind a low level of some increasingly oily gloop that doesn't mix with air or burn easily. That's what the pump is doing, diluting this stuff out.

[Grizzly]

I had a similar problem........ next time your car has been stood any length of time take the float covers off and check how much fuel is in the float chambers, if the fuel is level with the spill valve in the bottom of the bowl you have a problem.

The reason I found for this on my car was the Pump jet ball wasn?t completely sealing so over the space of a week or so it would syphon all the fuel out of the float chamber.

I bought a cheap endoscope (the ebay type that plugs into your phone) then monitored the pump jets over a few days, what I saw was no dripping just a bubble of fuel on the end of the jet that never went, even if I wiped it off it would return 30 mins or so later and that was very slowly syphoning the fuel from the float bowl. Of course you can mask this with an electric fuel pump but since I fixed mine it starts with one half depress of the throttle and one revolution of the starter even after a couple of weeks layup (using the factory mechanical fuel pump).

I?m not going to tell you this was an easy fix (it was a pain to stop and I?ve only got three cylinders 100% fixed) but such a small thing makes a huge difference.

[gjz30075]

Chris, pm sent