1969 VW Beetle 1600cc - Engine Problem

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Sun 30 May 2010 15:57
1969 VW Beetle 1600cc - Engine Problem - Pacific

My car recently developed engine problem. The engine would turn backward a few turns for a few seconds before it stopped completely. This does not happen all the time but mor often when engine is hot. The coil is new and so is the distributor. All the valves have been checked and cylinder head has been overhauled. Its running on a Twin Carb and the engine is running very smoothly without any problem. The only fault is the engine continues to turn backward for a few turns before it finally stopped. It sounds as if the compression within the combustion chamber forces the engine turns backward when I switched off the ignition. The guys at the workshop and I are at a lost. We sure can do with some advice. Help!!!

Many Thanks

Pacific

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Sun 30 May 2010 18:00
1969 VW Beetle 1600cc - Engine Problem - jc2

That's a blast from the past.It's called "run-on";The engine can continue in either direction of rotation after the ignition is switched off.Usually caused by part of the combustion chamber getting too hot-either glowing carbon or a very thin metal edge.Does not occur on engines since the 80's due to injection systems and carbs. with idle shut-off valves.

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Sun 30 May 2010 18:42
1969 VW Beetle 1600cc - Engine Problem - Peter D

If the top end has been overhauled and the pistons were cleared of carbon then it sounts if you have fitted plugs that are rated at a higher temperature and causing the pre-ignition. Check what is fitted and use a colder running plug. Do you know what CO it is running at, is it too rich. Regards Peter

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Mon 31 May 2010 02:45
1969 VW Beetle 1600cc - Engine Problem - Pacific

Hi Peter,

Many thanks for your advice, first of all just to let you know that I moved to Malaysia 2 years ago from UK and my Beetle is at one of the workshop in Kuala Lumpur ,and the workshop here is of the old school type without sophisticated diagnostic machine. There is no carbon deposited within the all combusion chambers. I don't think they know the CO level which the engine is running on ( they don"t have the machine to measure the level). They told me the Carbs are ok because the car is running very smoothly. The Plugs are Bosch Platinum and I have been using them for nearly 6 months prior to having this problem. Any further advice from you will be much appreciated.

Pacific

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Mon 31 May 2010 04:15
1969 VW Beetle 1600cc - Engine Problem - Pacific

Many thanks for taking your time to answer my quesion.

Regards,

Pacific

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Mon 31 May 2010 06:59
1969 VW Beetle 1600cc - Engine Problem - Peter D

http://www.vw-resource.com/wires_plugs.html#plugs

Regards Peter

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