G'day again all,

3 weeks ago I serviced my 1600 twin port (#ADxxxxxx) then it busted both valve springs on number 3 during it's test drive. :cry I replaced them with secoind hand ones, re-did the tappets then drove it to Coffs Harbour and back (3360km) over the following week no problems.

2 days ago I drove it again just into town and back no problems and parked it in the garage and today I serviced it again starting with the tappets and number 3 inlet valve spring is busted again.

Does anyone know of some weird known fault my engine might have that causes this sort of thing or am I just unlucky?

PP.
ps. I'm running out of spare valve springs here!

My guess is rocker geometry or rockers

Where is it breaking? Top, bottom or just breaking???

I can only assume you are having too much travel in your rocker and binding the spring and breaking from there.

Maybe a valve seat is loose and giving a wrong reading when you set the valves ??

If it was ok before you serviced it then it sounds you are making a mistake

get someone from your nearest VW club to come and give you a hand.

bound to be something simple you are missing.

Thanks guys,

I'm presuming it's a stock motor. The rocker gear looks standard but then I wouldn't know what a trick setup looked like either.

I put the motor in the car as I got it (in good nick with new oil, plugs points etc) and had driven it for a few hundred km before doing the service on it so I presume it was OK beforehand. When both springs busted it started running on 3 until you got a few revs up but when I drove it into the garage on the weekend it was running fine but with a very obviously broken inlet valve spring. The springs broke at about 1/3 of their length.

Is there a top and bottom to these springs and I'm putting them in the wrong way around? The coils are wound tighter at one end than the other and I've put the loose wound end to the head.

All help greatly appreciated,

PP.

Yep the tight wound end goes toward the head. Have you checked that the springs are not binding?

Thanks 242,

OK, so I've put the springs in the wrong way around, I'll fix that.

Now, what do you mean by "are the springs binding" please??

PP.

Watch a full cycle of the cam.

Maybe when the cam is at its highest point it is "crushing" the spring. ie compressing it more than it should.

Normally a problem when lumpy cams are used and the rocker geometry is not right.

Thanks for the explanation blue,

I'll check it out this weekend.

PP.

Springs are the right way around ( I don't wear glasses for nothing) and no they are not binding. They don't even come close to binding and after running the engine for about 5 minutes while using the timing light all my springs are still intact.

Hopefully this is the end of it :thumb

PP.