Poor start from cold... faulty pump?

[Tipidave]

Hi All, 

I have just purchased a 1965 1200 herald convertible that runs beautifully once started but it takes considerable time to fire from cold. The car was stored for 9 years prior to purchase. Is it likely to be the fuel pump diaphragm? On starting there are no visible exhaust fumes so I am thinking this is best place to start. Can I overhaul the pump? Or will a new pump be best?  Any other ideas? 

Thanks

[Pete Lewis]

Pumps are in many cases repairable but there are a lot of pump designs out there 

New might be best option, and a clean through the feed pipes

As its stood do check that when you operate the choke it has not seized and the flap in the carb throat stays open, 

Change all fuel  hoses to Gates R9 Spec.especially the one in the boot , these get ignored go hard and the pump sucks air not fuel

Its the one ontop of the reserve lever

Pete

 

[NonMember]

1 hour ago, Tipidave said:

I have just purchased a 1965 1200 herald convertible that runs beautifully once started but it takes considerable time to fire from cold.

Can you quantify that last bit, please? How long is "considerable" and how cold is "cold"? My GT6 regularly takes 30 seconds to start after it's stood for a couple of weeks, which is quite normal for them because the carbs dry up and need re-filling. A Herald has less float chamber volume to fill but also a slightly smaller pump. Of course, if you're seeing problems the morning after a run then that shouldn't be the cause.

[Tipidave]

Thanks for the reply... by some while I mean two minutes plus. Later same day 7 to 8 hours. Restarts well an hour or two after running. Have only just got the car so haven't had much chance to play with it yet. ??

[Colin Lindsay]

In all likelihood your fuel is draining back from the system and needs time to get repumped back to the carbs; obviously the longer you leave it the longer a restart takes. Is there a priming lever on the pump? 

As Pete says a new pump with new valves that will (hopefully) keep the fuel in the pipes should cure the problem; it won't be the diaphragm but a valve that's faulty.

[Badwolf]

I have noticed that the level of fuel in the see through filter drops over a period of time (1 to 2 weeks if not used) and the car takes a little time to start. I thought if was evaporation. Should I be looking for something more seious. No sign of leaks or smell of petrol.

[Anglefire]

Interesting article from BP here: https://www.bp.com/content/dam/bp-country/en_au/media/fuel-news/petrol-life-vehicle-tanks.pdf

 

[Colin Lindsay]

On 7/21/2018 at 10:00 AM, Badwolf said:

I have noticed that the level of fuel in the see through filter drops over a period of time (1 to 2 weeks if not used) and the car takes a little time to start. I thought if was evaporation. Should I be looking for something more serious.

No, mine sits full all the time and never drops despite weeks or even months of non-use. Yours is just draining back from the pump through a non-sealing valve. You can live with it - expect more pumping or cranking before it starts, which if nothing else will circulate the oil around the engine first, or else invest in a replacement pump.

[Tipidave]

I read with interest the article in this months corrier detailing the problem of higher pressure from a replacement pump.

Could the solution be as simple as to flush and blow through the existing pump ? 

[Colin Lindsay]

If it's debris holding a valve open, that would work, but if it's just wear and tear, it won't.