21 replies to this topic

[Sawyer]

Hello,

 

I am hoping for some advice of where to look next please..

998 I've owned for a few months which has an annoying tapping noise, tapping increases with engine speed.

Fans not catching and I've checked valve clearances, all seem good 0.30mm.

Noise does seem to be coming from the right hand side, is timing chain the next component to check out?

 

See link to youtube video to hear noise.

 

https://youtu.be/JVtVKHmf7Y8

 

Ben

[Avtovaz]

i would say, [and its a pure guess] its half engine speed. So id look at your tappets again? as i say a guess.

 

I dont know what they are like on  minis, but on Ladas they could wear, and you could put a feeler gauge in, and it would cover the wear in the rocker. maybe worth taking them off for a look.

 

Or wait for more ideas.

[Sawyer]

Thanks Avtovaz. I did expect tappets to be out of tolerance so was surprised to find they were ok.

Previous owner may of tried them, you can see someone has done them before with a poorly fitting spanner as some of the corners are marred.

 

I checked each tappet with a .30mm feeler gauge and it fitted in with more or less drag across them all. I didn't have to force the gauge and none slipped freely although there were varying ranges of resistance. I was hoping to find no 1 and/or 2 out of spec, the noise in the flesh is very much coming from the right hand side like it could be the radiator fan, I have had that in the past on other minis.

[PoolGuy]

A slight blow from the exhaust gasket can sound like that (it could be the limitations of video sound though)

[Quinlan minor]

These can be helpful when locating the source.

NOTE: Great care must be taken when using on a running engine.

 

This is an example they can be sourced at a great variety of prices.

https://www.ebay.co....02&algv=Default

 

[1314cc]

In the past I've twice come across a tapping/ticking sound and turned out to be a blown head gasket.
May be worth doing a compression test?

[1314cc]

Just watched the video and sounds just like what I've experienced. Head gasket blown between cylinders. Any power loss?

[johnv]

Does it sound like this?
https://youtu.be/Vmn2tci1Fco

[Sawyer]

Thank you 1314cc, it is the first 998 I've owned and driven so I don't have any comparison to power. It is slow but gets there eventually! it will comfortably sit at 60mph. As suggested I will compression test, hopefully get this done later today.

[Sawyer]

JohnV yes that sounds very similar, what was causing your issue?

[johnv]

The timing chain sprocket on the cam was loose and the noise was coming from the slifmght play it had on the woodruff key.. if that makes sense

[imack]

Could be a worn out rocker pad, even if you've set the clearances with a feeler it'll still be wrong. I'd run the engine without the rocker cover fitted and carefully slide a sacrificial feeler blade under each rocker pad in turn while the engines running. If the tapping disappears you've found the problem.
YOUR FEELER BLADE WILL BE DAMAGED IN THE PROCESS.

[Sawyer]

Good evening,

So I carried out a compression test and looks good to me.

 

[Sawyer]

Noise does seem more audible when removing the rocker cover and when I was playing around undoing the bolts the noise did stop temporarily and then gradually come back again.

I checked and am confident the manifold isn't blowing although the noise is definitely more prominent from the rear of the engine, I could replace the manifold to head gasket and rule that out?

 

Imack, I like your suggestion, I am guessing you are talking from experience?

 

Here is another video with rocker cover removed, the engine did NOT want to idle with the cover removed, I am guessing this is normal. I had to open the choke a touch to stop it from stalling.

 

https://youtu.be/Fo_GN9v09Zk

 

Ben

[RustyAutoCityE]

These can be helpful when locating the source.

NOTE: Great care must be taken when using on a running engine.

 

This is an example they can be sourced at a great variety of prices.

https://www.ebay.co....02&algv=Default

 

You can also use a piece of wood/long screwdriver (handle side ) held to your ear to help locate the source of the sound.