What a weekend (plus help needed on starting issue)

[Alan c]

I work overseas and this was my first weekend back in the UK in 2 months, so what a real treat with the weather. The cover was off the Marlin as soon as I had breakfast on Sunday mornning. The Marlin sitting for a few months meant a few extra cranks followed by a splash of petrol down the carb to get it to bite. Once away a few hours of riding around the still quiet Surrey country back roads was a real joy. There was also clearly a high proportion of people with the same thoughts as there was more than the usuals number of classics, soft tops, kit cars etc out on the road.

As for that poor starting after sitting. The car has a Pinto 2L fitted with mech fuel pump. I am assuming the fuel is draining back over time (its Ok starting within a few days but after a week it can take minutes of cranking, even with a new battery I am on borrowed time for a no start). Has anyone had this problem I was contemplating some sort of non return valve. But I did wonder why no residual fuel in the carb float chamber?

Its clearly a fuel issue as soon as a dash of petrol down carb it fires.

Thoughts anyone.

[cameronfurnival]

Re: What a weekend (plus help needed on starting issue)

The fuel pump has non return valves in as standard so that is unlikely to be the problem, in any case the pump will pull fuel back up the line in just a couple of pumps. More likely is the fuel - modern fuels are probably more volatile than those for which your carb was designed for so over a relatively short period of time it will flash off. The best solution is probably to replace your manual lift pump with an (low pressure) electric one which will prime the carb without having to crank the engine.

[CompoSimmonite]

Re: What a weekend (plus help needed on starting issue)

Unleaded fuel goes off quite quickly. Whilst a couple of months probably isn't enough to cause the problems in this case of reluctant starting it's worth noting. In fact stale fuel is one of the most common reasons why petrol garden tools won't start after being laid up over winter ! My motorbike (Honda CB400A) flatly refuses to fire on fuel that is over 6 months old whereas drain off old stuff, refill with fresh and almost an instant start.
I had a diesel Land Rover that there was a non return valve in the fuel pipe. Wasn't a standard part but an aftermarket item so maybe a diesel parts specialist might be able to provide something suitable. When unleaded evaporates it leaves behind a mess that can block jets so better to drain carb before it is parked up if it's going to be left for any period of time.
Personally I'd go one of two routes - fit electric fuel pump or keep a second battery fully charged that can be used with jump leads. BTW you can get petrol quality fuel taps both manual and electric solenoid operated. They might be worth considering as a way of cutting off fuel supply so you can run engine so float changer emptied before storage. LPG parts suppliers can provide a suitable solenoid operated valve. They are also a good additional antitheft device as they allow the car to be started with the fuel in float chamber but quickly stalls.

Paul H

[Alan c]

Re: What a weekend (plus help needed on starting issue)

Thanks for the feedback. The fuel is only a few months old and runs OK when it starts so I think we are OK there. The evaporation of the fuel from the carb sounds like the problem I will look at the LP fuel pump option. I assume if the check valves in the mech fuel pump fail then the fuel pump will not work as they are the pumps working valves.

Thanks

[jon_cox]

Re: What a weekend (plus help needed on starting issue)

Hi Alan,
I used to have the same problem with mine. I have a Fiat Twin Cam running twin Weber IDF carbs and the poor old mechanical pump used to take ages to fill the carbs up enough to get the car to start from cold. Then when the engine was hot and left the fuel would evaporate even faster. I replaced the mechanical pump with an electric one. I sourced the type that can be fitted in the engine bay as I did not fancy crawling around under the car fitting one by the tank. Problem now solved and the car fires up instantly.

http://www.fastroadcars.co.uk/shop/index.php?act=viewProd&productId=29

[danny_nelson]

Re: What a weekend (plus help needed on starting issue)

Hi Alan,
You were right in the first place. With a manual pomp fitted on a Pinto the fuel can drain back and is quite common. Ypu can put an in line valve in place, but consider this first. One of the Pintos problems is oil feed to the cam (we all know about the tapping cortina) An up graded spray bar was available but it was never good to have a pinto start first turn of the key in case the cam was dry, or at least some of them dry. So much so we uuse to put a wire and switch to the coil so we could crank them over a few times without fear of starting , then throw the switch and start with the cam oiled!! So my point, put an electric pump on and if you have no switch then instant start, maybe better to leave the manual pump and crank it over a few times?

[cameronfurnival]

Re: What a weekend (plus help needed on starting issue)

That's really interesting Danny, I thought the ford pump units had non return valves built in? Maybe they dont seal so well? Good point about the spray bar, many a pinto went to the scrapyard because of that particular fault. Im left wondering then that maybe Alan's starting circuits are failing, maybe the battery doesnt have enough umph in it?

[greyV8pete]

Re: What a weekend (plus help needed on starting issue)

I fitted an electronic fuel pump (from Merlin Motorsport) to my classic a few years ago as I was having vapour lock problems with the nasty unleaded fuels. I fitted it to the chassis rail right next to the tank so the whole fuel line was pressurised and it kept it well away from engine temperatures. Result is absolutely no further problems. I also have a cut out switch under the dash so I can crank the engine a bit before pulling out the choke knob (remember those!) and starting with the pump switched on. Peter.

[Alan c]

Re: What a weekend (plus help needed on starting issue)

The plot thickens as they say. Thank you for the feedback.

The battery is brand new and all the ignition circuits seam in good shape (it starts great even after a good few days standing - its only the few weeks when it starts to be an issue). It was also on a rolling road a few month back and got fully tuned so settings should be optimum.
I may research how mech fuel pumps work as I suspect their inbuilt valves do provide non return. It may be mine has seen better days and new one may be in order, if not or if that does not work then plan B is fit inline check valve, plan C elec fuel pump. The spray bar is a bit of a worry - I think when starting fixed I will look at how quickly it starts and do the coil trick Danny mentions.
As I am away I am also having to have its serviced/MOT'd by local old school type garage - asked them to give a 2nd opinion once over on the whole car. Maybe something will pop up then.

[bill howitt]

Re: What a weekend (plus help needed on starting issue)

Alan, I have had exactly the same problem with my Pinto. Instead of just a NRV I've fitted a manual fuel priming pump as fitted in diesel fuel lines (eBay Item: 360384378555). In addition to a NRV it also allows you pump petrol up to the carb and fill the float chamber. If the engine has not been run for some time, when the pump is used you can hear the fuel flowing past the needle valve into the float chamber indicating that evaporation has occurred. The pump is fitted close to the mechanical pump input and is situated so that the chassis rail (Berli) provides protection from stones etc. Yet to try it on the road to prove that there is no adverse effect on fuel flow when under load as the car is SORN until May. Bill.

[cameronfurnival]

Re: What a weekend (plus help needed on starting issue)

Just picking up on the problems of too little oil in the pinto engine, isnt the cure to improve the oil flow rather than delay starting? This is an engine which I have only limited experience with (I think I rebuilt a couple back in the 80s - guess why?) but I wonder if there is an uprated oil pump and improved spray bar? Or is it dwn to oil type, didnt the pinto use 5w30? Just interested.

[lizbillings]

Re: What a weekend (plus help needed on starting issue)

Bluebelle winds over for ages when left more than a couple of days but at least the oil pressure has time to build up. In fact it winds over so much that the oil pressure light goes off before the engine starts. A higher capacity battery has helped as has a warmer garage. When trying to start I have to be very careful not to use the accelerator and flood the engine. Doug

[Alan c]

Re: What a weekend (plus help needed on starting issue)

I like this - cheap simple and fills two functions (I owned a couple of motor boats at one time and they had these - and worked well - I should have joined the dots and made the link). It would appear this has a built in NRV. I assume its fitted before the inlet side of the mech fuel pump. Thanks.

Alan, I have had exactly the same problem with my Pinto. Instead of just a NRV I've fitted a manual fuel priming pump as fitted in diesel fuel lines (eBay Item: 360384378555). In addition to a NRV it also allows you pump petrol up to the carb and fill the float chamber. If the engine has not been run for some time, when the pump is used you can hear the fuel flowing past the needle valve into the float chamber indicating that evaporation has occurred. The pump is fitted close to the mechanical pump input and is situated so that the chassis rail (Berli) provides protection from stones etc. Yet to try it on the road to prove that there is no adverse effect on fuel flow when under load as the car is SORN until May. Bill.

[Tony Stott]

Re: What a weekend (plus help needed on starting issue)

^ pump lubrication, will it not be stripped of lube by the petrol, as if its for diesel there is a level of lubricity therein?! just pondering as petrol in a diesel engine causes all sorts of probs with oil stripping.

[Alan c]

Re: What a weekend (plus help needed on starting issue)

They are a rubber hand pump like the one that the doctor uses to pump up the blood pressure strap on your arm. (spec on ebay - as it is now ordered - says OK petrol use). Only cost a fiver so not a big finacial gamble.