Cold start difficulty

[Kenyon]

There's a fair few discussions about cold start priming on the 356registry forum. I liked this article, shows how simple a squeeze pump on the fuel line in the engine bay.

https://porsche356registry.org/article/77

It does suggest cranking first to get some oil flow. And I suppose the other thing is to make sure the right clamps are used to secure the pump to the fuel line as referred to in here:

http://forum.porsche356registry.org/vie ... f=6&t=1968

[POR68]

True, a bit of cranking for oil pressure is always a good thing. Personally, I am not keen on an external and rather ugly 'bulb' fuel primer on these cars. There is the inconvenience and I have probably spent too many years with boat outboard motors and the priming bulbs that came from them. They also tended to crack/leak after time in the heat. I did spend some time working on getting my startup voltage as optimal as possible and eventually fitted one of Fred Winterburn's outstanding 6v CDI units. Amazing difference.

[Julian Hunt]

Over the years I found the method that seemed to work best for me was to simply turn the key, engage the starter and once it was cranking over start to push the throttle slowly to the floor, 99% success!

Regarding building oil pressure - if it's been sitting a while good idea. My old van doesn't get started very often so when I do I always crank it over with the ignition off to build oil pressure and fill the carb with fuel.

[silverboydreamer]

Post script
Hi, after reading all the above, I decided to pullout the carbs, strip and clean out all the passage ways/chambers with air and refit, at same time fitting a small fuel filter to petrol line. Also checked the points and redid the static timing at 5 degrees BTDC. Turned over engine to fill carbs and then linked up the throttle links, turned over again a couple of times whilst pumping throttle and the engine coughed and then caught, success!!!.
Can’t say what the cause of problem was just grateful it seems to be overcome( I hope ), thanks again for all your posts.

[neilbardsley]

PS if you don't like the bulb see this product for cold starts

http://forum.porsche356registry.org/vie ... 19&t=45541

[POR68]

I still suspect that a primer may be in your future. What jet sizes were in those Zeniths? They can get changed over the years.

Neil, the guys at PM never cease to amaze me with their design and development capacity. I wonder, has anyone ever fitted a choke or hand throttle cable to the 356 models that did not have this feature? Seems easier than waiting for a mechanical fuel pump to move enough fuel into the carbs and then going through the guesswork of the number of accelerator pushes to finish the job. My 68 SWB was a pain to start at times, but later 911 models with a choke, pretty straight forward.

[Kenyon]

Yes, the Precision Matters guys seem to have some great pieces of kit. Their website seems to have come down. I was thinking about one of the Dipstick Thermometers. Though that said I did manage to find a digital one for food that is effective and was pretty cheap.

[DavidHailMan]

I have a out board engine hand pump under the dash. When I have not used the car for a few weeks. I pump untill I feel resistance. Pump the throttle 10 times and hold the throttle open and It fires 1st time.

When hot I turn the it over with no throttle then open up 1/2 way and again away she goes.