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Pushrods Touching Head


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#1 merther

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Posted 17 June 2024 - 06:05 PM

Been having a ticking noise form the engine and it appears after looking the pushrods on 1&2 are touching the head hole causing the pushrod to have a scoring mark on them. Would this cause a noise like ticking tappets? Looking at number 8 the pushrod comes out of the head hole more central  than 1&2. How can cure this?



#2 imack

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Posted 17 June 2024 - 06:11 PM

What rockers are you using?
I think the old pressed steel ones had shims between the rock and post to correctly position the rocker pad and pushrod.
Not sure if sintered rockers had shims.

#3 Avtovaz

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Posted 17 June 2024 - 07:15 PM

are the rods bent?!



#4 merther

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Posted 17 June 2024 - 07:19 PM

are the rods bent?!

No all straight

#5 merther

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Posted 17 June 2024 - 07:19 PM

What rockers are you using?
I think the old pressed steel ones had shims between the rock and post to correctly position the rocker pad and pushrod.
Not sure if sintered rockers had shims.


I'm using old steel rockers

#6 imack

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Posted 17 June 2024 - 07:48 PM

I presume they'repressed steel, not forged steel Cooper S ones.

I believe there's different rockers for small bore engines (850, 998, 1098) and 1275's. Not sure whether you can swap rockers between small bore and big bore engines.
As previously mentioned, they need shimming correctly.

Edited by imack, 17 June 2024 - 07:50 PM.


#7 DeadSquare

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Posted 17 June 2024 - 07:48 PM

It would help to know if the pushrods are rubbing:-  front - back - or if sideways, which side.

 

If the rubbing involves enough friction, it might be possible for the pushrod to be left "hanging" so that the cam follower hits the bottom of the pushrod with a click, but I doubt it, as there is at least a smidgen of oil in the rocker chamber, and cam followers are also called 'cam buckets' and hold more than a film of oil, to lubricate the bottom of the pushrod



#8 Lplus

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Posted 18 June 2024 - 07:35 AM

I presume they'repressed steel, not forged steel Cooper S ones.

I believe there's different rockers for small bore engines (850, 998, 1098) and 1275's. Not sure whether you can swap rockers between small bore and big bore engines.
As previously mentioned, they need shimming correctly.

Minispares parts catalogue shows the same part no for all rockers from 850 to 1275 turbo.  We don't know what engine the OP has or if it has any mods at all such as head change, skimmed etc.



#9 imack

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Posted 18 June 2024 - 11:30 AM

Sintered rockers are the same for all engines, pressed steel are different.

#10 merther

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Posted 18 June 2024 - 06:16 PM

Sorry I should have been more specific.

 

its a 1275, running a swiftune cam and they are rubbing the front of the cylinder head hole (towards the front panel)

 

I’ve done a compression test (hot) and all cylinders are equal at 200psi. I took it for a run and I got a rather alarming rattle more than what I’ve heard before when I was deaccelerating turning into a road. 
 

The ticking/ rattle only seems to happen when the car is ticking over or I’m slowing down for a junction (de accelerating ) when it’s running along its fine. I can out the car into neutral and let the revs drop and the rattle starts again. It sounds like worn tappets but when I look at the tappets I can’t see anything alarming or anything loose to warrant this noise. 



#11 merther

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Posted 18 June 2024 - 07:09 PM

This is a vid of the tapping. Ignore the drop gear rattle.

It was considerably worse under de-accelration turning into one junction.

Edited by merther, 19 June 2024 - 06:58 PM.





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