356 Starting tip

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40 scout
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356 Starting tip

Post by 40 scout »

Anyone had problems starting up your 356 after a week or so?? I have and I think it's to do with fuel evapouration from the carb floatbowls.

Anyway I used to go in the garage a almost flatten the battery turning the motor / fuelpump over to get the old girl fired up.

New method works really well - goes like this -

Go in garage way before you wanna drive,

Fuel tap on

Spin motor over three times for 15 secs or so

Leave fuel tap open

Walk the dog

Go back into the garage

Spin her over - starts right up!

Take out for a good autumnal thrashing!

Works for me anyway

Cheers

Steve (hope this helps someone cos it took ages to type 1 fingered on an I phone!)
'72 911T - 212 BHP 2.7, on PMO's
'62 RHD T6 B outlaw
'71 Alfa GT Veloce 2000

1929 Indian 101 'bobber' project.
'40 Indian Sport Scout bobber
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Burma-Shave
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Post by Burma-Shave »

You can also install a primer bulb (got mine from from a chandlers) in the fuel line after the pump. You can hear it gurgling into the bowls on the third or 4th squeeze..very satisfying. 2 or 3 prods of the throttle, and she starts 1st turn - even after a few weeks..
1990 964 C4, 1999 Boxster 2.5
'89 BMW E30 325i Touring. '83 Mercedes 280E. '84 Citroen 2CV. '16 BMW i3 REx. '03 BMW R1100S. '99 Yamaha R1. '79 BMW R100 scrambler.

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40 scout
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Post by 40 scout »

hi johnny - a mate of mine had the primer bulb set up - squeezed a little too hard one day and managed to spray a pressurized jet of fuel around his engine bay (must have had a dodgy connection) anyway the fuel caught alight and the fire was fed with fresh petrol until the pressure subsided - probably was a great u tube type moment to see him trying to beat the flames out with an old pair of overalls!! No harm done in the end but the fuel bulb went in the bin after that episode :lol:

Steve
'72 911T - 212 BHP 2.7, on PMO's
'62 RHD T6 B outlaw
'71 Alfa GT Veloce 2000

1929 Indian 101 'bobber' project.
'40 Indian Sport Scout bobber
VW T5
!920's Racing Cycle
1920's Premier cycle
A few vintage Heuers

Member No 381
Burma-Shave
Put a fork in me, I'm done!
Posts: 1946
Joined: Mon Jul 31, 2006 9:52 pm
Location: Fife, Scotland

Post by Burma-Shave »

:shock: :shock:

Thanks for the tip. Going to squeeze a little gentler in future..like that audi quattro ad! Must check my fuel lines too, dont know how old they are... :roll:
1990 964 C4, 1999 Boxster 2.5
'89 BMW E30 325i Touring. '83 Mercedes 280E. '84 Citroen 2CV. '16 BMW i3 REx. '03 BMW R1100S. '99 Yamaha R1. '79 BMW R100 scrambler.

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Mike Smith
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Fuel Lines

Post by Mike Smith »

You should change ALL the Fuel lines every 2 x years - if you want to be really safe - the new fuels certainly attack whatever type of rubber the hose is made from

I dumped a gallon of fuel on the road a couple of years ago and that was my own car

It is T6 so the Fuel Cock and feed from it are outside the car (at the front of course) which allowed me to motor home without too much fear of fire

I sliced off the braiding to expose perforated rubber

We have seen a lot of cars like this since my experience - It is CHEAP insurance to renew regularly
Mike at P.R.S.
www.prs356.com
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Post by 912uk »

agreed I need to redo mine again I think the type of fuel hose we get now just does not last. I had some spare on the shelf and I noticed it was cracked and it was only sat on the shelf!!! never been used :shock:
roy mawbey
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Post by roy mawbey »

Being a new guy to the forum thought I would read a few of the old posts. This thread raised my interest. If your 356 has Zenith 32NDIX carbs they have individual accelerator pumps installed inside them. This means when you have to start from cold you turn on the fuel tap and providing you have started the car in recent times and there is fuel in the float bowls you then pump the accelerator pedal to the floor 3-4 times and petrol is injected in squirts into the venturis to give an instant start if everything else is okay! ( no choke of course on our cars )

This sort of replicates the squezing of a rubber plunger system but the Zenith system is safer I think. Over time the small accelerator pump pistons in the Zenith's might have their efficiency reduced if the leather type skirt dries out or wears out and the petrol pumped through the injection tubes reduces. Then you find you have to pump more times on the accelerator to start the car.

The exact amount of petrol that should be injected with each stroke of the carburettor accelerator pump is defined and the method of checking is detailed very well on the "registry" Zenith 32NDIX tuning pages well worth while reading. Stoddard sell new accelerator pump piston assemblies to rectify worn out ones.

Of course the mechanical fuel pump should be working well but normally if its wrong you won't be travelling very far!

Finally, if you take the aircleaners off and lean over the carburettor and get someone to press the accelerator pedal ( or depress the control linkage yourself) and you should be able to see petrol being squirted out of the injector tubes. ( It will show at least if they are working or possibly if the pump jets that connect to the injection tubes are possibly blocked.)

Roy
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Post by 912uk »

good point Roy our cars in general sit for months on end and then come the summer they are out all the time :lol:

I found probs just like you said about the accelerator jets not showing any fuel when operated this transformed the cars starting once that was sorted.. no good trying to start a car with one jet working out of 4 :shock:

I don't mind it cranking over a few times to get going then I know the oil is being pushed round before it does start.. some times I think we all want it to start like our moderns and that's not a good thing..
sjm
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Post by sjm »

Interesting thread Steve - I have exactly the same experience. As I am a total numpty when it comes to anything mechanical I called Paul at PRS when I had a problem, and he kindly talked me through what Roy has explained nicely above. And guess what....it only bloody worked! You have no idea how chuffed I was (like I said, I am a complete waste of space with a spanner).

Alas, my elation was short lived when I then found I couldn't get it in gear as the clutch had given up....so in the end Paul was out with the trailer to get me after all.... :cry:
Simon Moore
1958 356A
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roy mawbey
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Post by roy mawbey »

Over on the registry site this question rose again regarding the fitting of an additional rubber bulb to send fuel to the float bowls. I gained some info from that thread:

It would seem todays fuel evaporates more quickly than when we had leaded. If the car is left for a longer period of time the level in the float bowls drops and the accelerator pumps don't come into operation if you just pump the accelerator 3 times and expect it to start.

So some people have installed an electric fuel pump to push the fuel immediately into the bowls and then you use the Zenith accelerator pump
by pressing 3 or 4 times on the accelerator. Or you use one of these primer bulbs to get the correct fuel level.

But it would seem if you fit an electric pump, it should be turned off after you start and the mechanical one should take over otherwise too much pressure is imparted.

However! another response was if an immediate engine start is made using these devices without first allowing the engine to slowly crank over to build up oil pressure, the moving parts could be dry of oil increasing the chance of wear. ( Sure, the guy who wrote that had a carrera 356 dry sump engine )

So, at the end of this saga, at the at very beginning of this thread it was stated turn the engine over 20 times and walk away and come back to it and it will start. Well it would seem the 20 cranks brings up some oil pressure and fills no doubt to Zenith carb bowls but then before starting, it still might be best to depress the accelerator a few times to make the internal accelerator pumps work.

All this is valid, providing the mechanical fuel pump is in good condition and the small pistons with their leather skirts are not worn out along with injector nozzel jets being clear.

You learn a lot on forum pages but you don't have to follow every thing to the letter. I will continue my method but will possibly crank the engine first a few more times than before if I have left my car standing a while.

If your problem is not starting from cold but when the car is hot and it cranks over very very slowly its likely to be the bush that supports the starter motor output shaft has worn. When I found that out on forum pages it really made my day. (I had tried everything else, earth leads, battery, etc etc.)

Roy

Roy
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40 scout
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Post by 40 scout »

hate to say I told u so -but it works -x! - had a good drive yesterday :wink:
'72 911T - 212 BHP 2.7, on PMO's
'62 RHD T6 B outlaw
'71 Alfa GT Veloce 2000

1929 Indian 101 'bobber' project.
'40 Indian Sport Scout bobber
VW T5
!920's Racing Cycle
1920's Premier cycle
A few vintage Heuers

Member No 381
roy mawbey
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Post by roy mawbey »

I took mine out yesterday also. But I will be surprised if you took it out today! I must be about 30 minutes from you and its p-----g down here at the moment!

Roy
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Post by 912uk »

I was out yesterday Our way was nice and summer if abit of a chill in the air..summers coming 8)
40 scout
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Post by 40 scout »

Your right there roy - the car stayed in the garage today!

steve
'72 911T - 212 BHP 2.7, on PMO's
'62 RHD T6 B outlaw
'71 Alfa GT Veloce 2000

1929 Indian 101 'bobber' project.
'40 Indian Sport Scout bobber
VW T5
!920's Racing Cycle
1920's Premier cycle
A few vintage Heuers

Member No 381
Barry Wolk
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Post by Barry Wolk »

Please correct me if I'm wrong. Doesn't the fuel tank sit higher than the carbs when full? Wouldn't the fuel seek its own level and refill the carb as the fuel evaporates? Wouldn't this explain that it started right up after walking the dog?

I never turn my fuel supply off. If the valve is operating properly, why should I? I've never had to do that on any other car. Please enlighten me.
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