Plug leads

hi all , how long should the rubber insulator be from tin to cover the plug on type 4 ? As i think mine are short I’m getting misfire from erratic sparks
Thanks all.

 

Anyone have an idea ?

 

The correct insulated leads have Bakelite type spark plug connections. They are different lengths front and back. Reckon that unless you have the right plug connections it will be a thunderstorm in the engine box..

 

There was a time you could buy the long and short insulators separately. I tried a bit back but could only get a full plug lead set. VWH do a genuine Bosch lead set but it'll cost an arm and a leg. Make sure you also get the rubber grommets that fill the holes in the tin.

 

I see JK do a replica set now for £31, including grommets.

 

I wouldn't want anybody to think I was recommending these mind, but if it's £88 from VWH for the real thing you might be tempted (or were you grimacing at even £31 - cheap for us T4 owners).

Then again you can fit short insulators where they're supposed to be long, only about £6.50 a set and they'll work fine, just a bit more fiddly to fit.

VWH did a service bundle a bit back including the Bosch leads which was worth getting.

 

I wouldn’t be tempted with anything replica from JK.

 

Try sparkplugs.co.uk

 

I've heard about poor results from Bosch leads recently.

 

The 109mm long sparkplug caps are still available, they are also fitted to BMWs
Bosch part number 0 356 100 030

https://www.autodoc.co.uk/spares-search?keyword=021035255g

 

If you fit them, will your indicators stop working?

 

Thankyou all I will post my purchase and results from this

 

Bit of late update sorry , stateside tuning porche 914 leads set , good value great Fitment, in black with grommets & long reach insulators. All good