Tappets / Tapping noise

[bholleran]

I am looking for some advice for you good people.

I recently started getting a tapping noise from my tuscan, It starts as soon as the engine is running and increases in rate as the revs rise. It sound VERY like tappets, however I have checked and adjusted them, but the noise continues, does any one have any suggestions.

As per a previous post I undestand the tappet gap should be:

5 - 7 thou Inlet
10 - 12 Exhaust.

Values when I first noticed noise (Assuming 1 is at the front of the car)

Inlet
1 2 3 4 5 6 7 8 9 10 11 12
GAP 0.003 0.005 0.006 0.005 0.005 0.005 0.006 0.005 0.005 0.005 0.004 0.004


Exhaust
1 2 3 4 5 6 7 8 9 10 11 12
GAP 0.010 0.010 0.012 0.013 0.012 0.011 0.012 0.011 0.012 0.013 0.012 0.012


From This I decided to do the following:

Inlet: 1
Exhaust: 3,4,9,10

I know that 11,12 inlet are out but given it is not a lot and how akward it is to get to, I decided not to.

Current Values after adjustment.

Inlet
1 2 3 4 5 6 7 8 9 10 11 12
GAP 0.006 0.005 0.006 0.005 0.005 0.005 0.006 0.005 0.005 0.005 0.004 0.004


Exhaust
1 2 3 4 5 6 7 8 9 10 11 12
GAP 0.010 0.010 0.011 0.011 0.012 0.011 0.012 0.011 0.011 0.011 0.012 0.012


So by my reconing this all looks ok but I can still her the tapping noise.

Please help.


Thanks.

[tuscandom]

is it possible that you may have a valve sticking/worn valve guide,if the tappets are ok the problem may be further down,i read a thread on here a while ago,similar problem to yours(tappety tap tap) ,one of the valve seats had burnt not letting the valve close properly and making a tappety noise,im no expert on the subject,different point of view is sometimes helpful

[nelly1]

Could be the timing chain hitting the cam cover.

Are there any witness marks at the front?
The chain may need re-tensioning.

[bholleran]

nelly1 said:

Could be the timing chain hitting the cam cover.

Are there any witness marks at the front?
The chain may need re-tensioning.

Thank you, I think you are spot on the money, I dont know how I missed this when cleaning the excess silicon off the rocker cover before.

Yes I can now see what looks like new witness marks.

Do you know which way to turn the adjuster for the timing chain.. (I would have guessed clock wise) but I you know for sure it would be helpful.

Also do you know is there a certain amout of deflation the would be in normal rage. What i mean is I i took the rocker back off and but a steel rule across the timing chain cogs, and measure from the middle of the rule down to the chain to get the deflection?

I hope this makes sense.


Thanks

Barry

[bholleran]

I have adjusted the timing chain.

For information: The adjuster is in 2 parts. the bigger parts is a locking nut, and the smaller part is the adjuster. As best I can tell turn the adjuster anticlockwise to tighten the timing chain.

Back on topic, it did not fix my problem, yes it was a little loose and it did need adjusting. But the noise still persists.

In the mean time, I am going to adjust the remaining marginal tapets to the lower end of the range.

If it was a sticky valve would a compression test show this?

[tuscandom]

possibly/possibly not,would depend if the valve was stuck open when compression tested,might be that it is sticking enough to make a noise but then closes when engine is not running.is it cheaper to get a compression check or whip the head off and inspect it yourself ??? you sound like you have a good idea of what you are doing,i would go with the cheapest option first,keep us posted when you find the fault.cheers

[donaldhunter]

I guess you're not absolutely sure it's tappet noise and the clearances suggest it's not either.

Have you tried using a large screwdriver as a stethoscope and listened to the noise from different points along the head cover? Do you hear a significant tappet noise anywhere?

I had what I thought was tappet noise, but I'm reasonably sure it's actually combustion noise from the exhaust manifold. Maybe you have the same, although it doesn't explain why it started recently.

[phil350i]

have you adjusted both tensioners as the lower one can make quite a row if slack? p.s. anti-clockwise again to tigthten....phil

[bholleran]

OK I give up.

I have done the tappets and timing chain. The noise is still there. It is begining to sound more like a ticking rather than a tapping noise.

I have used a screwdriver to try and narrow it down, it still sounds like it is coming from the head area, only possible a little further down. It seems to be more obvious on cylinders 2 / 3.

I had to put more water in than I would have expected when I topped up. This made me start to think about the cylinder head gasket. Hmm.

Has any one ever heard of a blown cylinder head gasket causing a ticking noise?

I have checked the oil and water there is no cross contamination in either, there does not appear to be any loss of power or overheating. (to be fair I have not really tried for fear of breaking it more)

The only things I can think of that might cause ticking from the head are.

1. Tappets gap too big
2. Tappets gap too small (Not sure if this would tap or just affect performance)
3. Broken finger Follower
4. Worn Camshaft or finger follower (This would have led to a tappet gap? Is it possible to have the tappets correct and still have worn camshaft or followers and cause ticking?)
5. Valve sticking open (Would this cause a ticking?)
6. Cylinder head gasket (Would this cause a ticking?)

I think I might have to take it to Fernies and get them to have a listen.

Thanks for all the suggestions so far.

[bholleran]

bholleran said:

OK I give up.

I have done the tappets and timing chain. The noise is still there. It is begining to sound more like a ticking rather than a tapping noise.

I have used a screwdriver to try and narrow it down, it still sounds like it is coming from the head area, only possible a little further down. It seems to be more obvious on cylinders 2 / 3.

I had to put more water in than I would have expected when I topped up. This made me start to think about the cylinder head gasket. Hmm.

Has any one ever heard of a blown cylinder head gasket causing a ticking noise?

I have checked the oil and water there is no cross contamination in either, there does not appear to be any loss of power or overheating. (to be fair I have not really tried for fear of breaking it more)

The only things I can think of that might cause ticking from the head are.

1. Tappets gap too big
2. Tappets gap too small (Not sure if this would tap or just affect performance)
3. Broken finger Follower
4. Worn Camshaft or finger follower (This would have led to a tappet gap? Is it possible to have the tappets correct and still have worn camshaft or followers and cause ticking?)
5. Valve sticking open (Would this cause a ticking?)
6. Cylinder head gasket (Would this cause a ticking?)

I think I might have to take it to Fernies and get them to have a listen.

Thanks for all the suggestions so far.

Just a thought, the last 2 times I ran the car when I sat at idle there was a small pool of water below the passenger side exhaust at the rear of the car. Is this the exhaust that goes to cylinders 1,2,3? The other side was dry.

I only notice the water after I stopped the engine and was about to put her (Her name is Lois) back in the garage.

[L1OFF]

phil350i said:

have you adjusted both tensioners as the lower one can make quite a row if slack? p.s. anti-clockwise again to tigthten....phil

Are there 2 adjusters? I can only find one.

Alan

[bholleran]

L1OFF said:

phil350i said:

have you adjusted both tensioners as the lower one can make quite a row if slack? p.s. anti-clockwise again to tigthten....phil

Are there 2 adjusters? I can only find one.

Alan

Yes there are two, the second one is lower down on the left of the engine. If you have air conditioning it will be behind the air conditioning pump. I had to have it pointed out to me. If I get a chance I will try to get a better description / photo to you.

[so called]

It wont be piston slap will it or a small end bearing ?

[bholleran]

so called said:

It wont be piston slap will it or a small end bearing ?

Would piston slap sound like ticking?

I dont think it sounds like small ends, would that need the head off to fix or is a complete strip down.


Also what about fuel injectors?

[so called]

I had a problem in Germany earlier this year,
The ADAC man said bust valve, piston slap or little end bearing.
I've never heard piston slap mayself.
Hopefully yours is not a wear problem anyway.

By the way ADAC man was wrong, valve shim had moved.

[Tuskaa 7]

Could be way off here, but had a similar noise recently. Both TVR dealer and myself initially thought top end, tappet or finger follower. Turned out to be slipped liner.

[L1OFF]

bholleran said:

L1OFF said:

phil350i said:

have you adjusted both tensioners as the lower one can make quite a row if slack? p.s. anti-clockwise again to tigthten....phil

Are there 2 adjusters? I can only find one.

Alan

Yes there are two, the second one is lower down on the left of the engine. If you have air conditioning it will be behind the air conditioning pump. I had to have it pointed out to me. If I get a chance I will try to get a better description / photo to you.

thanks mate, will have another look.

[bholleran]

Tuskaa 7 said:

Could be way off here, but had a similar noise recently. Both TVR dealer and myself initially thought top end, tappet or finger follower. Turned out to be slipped liner.

How did they fix / diagnose it?

[L1OFF]

L1OFF said:

bholleran said:

L1OFF said:

phil350i said:

have you adjusted both tensioners as the lower one can make quite a row if slack? p.s. anti-clockwise again to tigthten....phil

Are there 2 adjusters? I can only find one.

Alan

Yes there are two, the second one is lower down on the left of the engine. If you have air conditioning it will be behind the air conditioning pump. I had to have it pointed out to me. If I get a chance I will try to get a better description / photo to you.

thanks mate, will have another look.

nope, still can't find it.

Alan

[donaldhunter]

Yep, a blown head gasket can make a ticking noise, I'm afraid.