GT6 Rocker tap

[Alex Lowe]

Hi all I took my GT6 Mk3 project out for a quick road test for the first time over the weekend as the car has been off the road for 20 years and after about 5 miles i noticed a tapping sound coming from I believe the rocker shaft as it sounded rather high up in the engine bay and I was wondering if anyone knew what could be causing this as it was not present before setting off. 

My initial thought was it could be the valve clearance could of changed as the car haddent been run at road speeds for so long or could it be something more serious like oil pump problems? As this is my first project im unsure if its anything serious to worry about or not.

thanks in advance guys been so helpful so far

[JohnD]

A stethoscope, either a pukka job,

or a broomstick held to the ear,

can isolate many noises.

john

[Pete Lewis]

or a nice wooden handled screwdriver.

keep it out the fan or a A &E NEED TO EXTRACT IT

i would reset the tappets to 0,010" cold  take into account there will be some wear on the tappet pad 

insert an old feeler in while running at idle , if it makes it go quiet you need to re adjust ,

there are other things taht make tappet speed noises but sort the rockers/tappet  out as first simple check.

use a rule of 13    ie 1 down set 12  etc.

pete

[Colin Lindsay]

Does that broom handle really go right through his head??

[Pete Lewis]

its a  case of fan blade interference        

the engine looks a bit rough.....not whats on his Tee shirt

[Mark B]

I just bought the same stethascope off eBay to try and isolate a similar tapping noise. Only a few quid. I just wanted to make sure the noise was coming from the top half of the engine which the stethoscope confirmed.

Worth checking the oil supply to your rockers if the engine has stood for a long time, as the initial loud tappet noise on start up after the rebuild of my Vitesse engine was gunk in the recon unleaded head oil gallery, and very little oil was reaching the rockers. This was mostly poked out with a piece of mig wire, and the hope was once the engine had been ran upto temperature a few times any gunk left would resolve or dislodge  

Tappets re-set twice and little change, so probably wear or lack of oil to the rockers in my case, under further investigation.  

[Peter Truman]

In the late 70's on a long drive back from Phillip Is in 40C temp our 2599TC developed a very noisy rocker assembly on dismantling it was scored and some rockers lacked full movement, The cause was lack of oil, the little countersunk bolt/screw that hold/locates the rocker shaft had come out letting all the rocker oil to simply pump out draining straight back to the sump. I had to temporally rob the Vitesse Mk2's full assembly till I could rebuild the rockers! Ref the countersunk bolt fortunately it was too big to fall thro to the sump and had lodged against the rear push rod.

My Mk2 Vitesse in the early 70's whilst still in the NE of England suddenly developed a top end "tap" I removed the head checked the push rods, removed the rocker assembly checked all OK, thought a valve might be sticking so gave each valve a tap on the top with the hammer to ensure they moved freely all appeared OK. Time dictated that I put it all back together, NO TAP! and that was nearly 50 years ago and I haven't removed the head again! was the fix luck or ignorance! 

Peter T

[Pete Lewis]

Pete ,  luck or ignorance   thats a new one,

Its a classic they sit outside and listen to you then decide what gremlin they can give to plague the owner just when they are going out in a clean shirt  

And  then when you find the fault it never cures the  problem 

Happy days 

Pete