Gti-6 Tapper Fixes....

[Stu 18]

Hi all,

 

My newly fitted '6 is a tapper, which i knew about, i mainly wanted to get it running and converted as the engine was cheap.. But.. The engineer in me cant leave it tapping

 

So, the infamous 'tapping'.. I presume the noise is a bent valve not seating properly as per any other engine, but, before i go reconditioning is there anything else that causes the noise?

 

Ive got a spare head that i'll rebuild, my action plan was to check the run out on all the valves with a dial gauge and a machined v block (spare press tool ) to make sure they're dead straight, then once i know ive got a known quantity of straight valves check the guides for play, anyone got a tolerance for this?

 

Is there anything else i should look for? Obviously it'll be skimmed (once ive checked the height ) and rebuilt with stem seals and a gasket kit, just wondered if theres owt else i should be looking for?

[chipstick 382 1 Cars]

Make sure it is actually a tapper, and not just the injectors ticking which is very common. There is a distinct difference in noise. You probably realise this, but worth mentioning.

 

You are best off replacing every valve to be sure while it's apart.

[Stu 18]

I can safely rule out injectors, owing to it running 45's

 

I hear bent valves damage guides which makes sense, but i dont see how a guide could cause a tap unless its worn to the point of the valve running out of true?

[welshpug 1,627]

check the guides are central to the valve seats, sticking a new valve in a damaged guide could mean it doesnt seat properly.

[CosKev 16]

All 8 exhaust valve guides needed replacing in mine due to wear,head was not a tapper,bought it to rebuild as you are doing.

 

Had all valves checked and two or three were found to be slightly bent so were replaced.

 

You are best off replacing every valve to be sure while it's apart.

 

Thats a bit OTT if you can get them checked properly and they are not worn out.

 

Bloke that did mine in engine shop said its easy to check them.

[Mad Scientist 106]

Just had a head done by Mark Shillaber at SRD. The head I sent had come from a snapper and several valves were bent right over. None of the guides were damaged or needed replacing. Make sure you get a trusted opinion before you spend money.

[Stu 18]

Just had a head done by Mark Shillaber at SRD. The head I sent had come from a snapper and several valves were bent right over. None of the guides were damaged or needed replacing. Make sure you get a trusted opinion before you spend money.

 

Good point bud, for me, unless the head has been a tapper for a while and hence the bent valve has killed the guide it'll be obvious; the first thing to do is get it apart, identify which valves are bent (im expecting at least two ) then check those guides firstly..

 

Thanks for all the input guys!

[welshpug 1,627]

exactly that indeed