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Newbie asking for some help with noisy tappets

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LowCarbs Thomas W
Boston, MA, USA   USA
1977 MG MGB
That's a great trick to remember. Although i think he replaced rockers and shafts already. About the only thing left is pushrods, which he has on order.

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GlennMGB Avatar
GlennMGB Glenn G
Fort Worth, Texas, USA   USA
1967 MG MGB GT "Rose"
I just listened to the video, and I agree that it is one tappet, or possibly two. It should be easy to figure out which ones are noisy by using a mechanic's stethoscope or a piece of hose to your ear. With the rocker cover removed and the engine running, put the other end of the hose near to each pushrod hole in sequence. The culprits will soon be apparent. Finding the exact components may be more difficult, as you'll need to rule out the cam, tappet, push rod, rocker arm, adjusting lug and rocker shaft.

Southdpwns Martin Koronka
Arundel, West Sussex, UK   GBR
Dear Douglas
Many thanks for your thoughts however, the entire rocker shaft is new and the camshaft and followers also. All of the B's I've had I've managed to silence somehow but this one is proving more stubborn than usual.

Some say that one can run the gaps at ten thou but I'm a great believer in engineers and they set it at 15 thou for a reason but, at the moment, this one has the better of me. I'll see if the pushrods help and report back.

This is though, the very best forum I've used: clear, logical thoughts from lucid people that know their subject.
Martin

In reply to # 3493570 by Grenehurst Dear Martin,
This always was a weakness of the "B" engine.
The rocker shaft wears, and becomes scored - this in turn wears the rocker arm bearings.
I think that you can still obtain the rocker arm bearings, as they are a standard size.
Changing them is not difficult, although you have to measure the bearings for the location of the two oilways, and then drill them before pressing the bearings in to the rocker arms.
The bushes/bearings will need reaming to size after fitting - I think that I still have the correct reamer safely stored away.
Did you check the camshaft followers when you changed the camshaft?
Please let me know if I can be of further assistance.
Kindest regards,
Douglas



Currently MGB GT, 73
Two midgets
Morris Minor
VW Camper van
Morris 1300

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Grenehurst Avatar
Grenehurst Douglas Wragg
Haywards Heath, Sussex, UK   GBR
1928 Morris Cowley "Leslie"
1963 Rover P4 "Lord Peter"
Dear Martin,
Many thanks for that.
I am assuming that the rocker pads are ok.
If it is of any help, I have a sonoscope, and as we are not that far from each other, it would be quite possible to bring it over and have a listen to the engine.
Should you wish to contact off line, my e-mail address is dgwragg@tiscali.co.uk
Kindest regards,
Douglas

Southdpwns Martin Koronka
Arundel, West Sussex, UK   GBR
A big thank you to everyone for your help and input.

I collected the pushrods, fitted them and adjusted the rockers to 14 thou.

It's as bad as ever.


Just to re-cap: New Camshaft, followers, pushrods, rocker assembly, timing chain and tensioner.

Not sure I can live with that noise.
Regards
Martin



Currently MGB GT, 73
Two midgets
Morris Minor
VW Camper van
Morris 1300

Grenehurst Avatar
Grenehurst Douglas Wragg
Haywards Heath, Sussex, UK   GBR
1928 Morris Cowley "Leslie"
1963 Rover P4 "Lord Peter"
Dear Martin,
This is inded an interesting problem!!
As Sherlock Holmes would have said - "Pray leave me Watson, for this is a two pipe problem."
It is the Stoneage Axe Syndrome - replace the head and the handle, and it should work.
You have renewed everything, and yet you still have this noise!!!!
Could it be that the noise is coming from elsewhere?
Let me know if I can be of practical assistance.
Kindest regards,
Douglas

Southdpwns Martin Koronka
Arundel, West Sussex, UK   GBR
Hello Douglas,
I think another Sherlock Holmes expression was 'one will find it in the only place one hasn't yet looked' or words to that effect.

On that basis the other obvious candidate is a mismatch in the face of the the timing chain cogs but I did measure that very carefully and, as far as I could tell, they were spot on. Straight edge steel ruler and no gaps on either cog. Also the noise is definitely from the tappet area. I did measure the old camshaft lift prior to swapping the camshaft and number five had slightly less lift than the other but hardly noticeable.

Curiouser and curiouser

Martin

In reply to # 3494797 by Grenehurst Dear Martin,
This is inded an interesting problem!!
As Sherlock Holmes would have said - "Pray leave me Watson, for this is a two pipe problem."
It is the Stoneage Axe Syndrome - replace the head and the handle, and it should work.
You have renewed everything, and yet you still have this noise!!!!
Could it be that the noise is coming from elsewhere?
Let me know if I can be of practical assistance.
Kindest regards,
Douglas



Currently MGB GT, 73
Two midgets
Morris Minor
VW Camper van
Morris 1300

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Grenehurst Avatar
Grenehurst Douglas Wragg
Haywards Heath, Sussex, UK   GBR
1928 Morris Cowley "Leslie"
1963 Rover P4 "Lord Peter"
Dear Martin,
The other quote from SH which comes to mind is - "When you have illiminated all the impossibilities, what is left, however improbable, is the answer."!!!
O, for a workshop where I could get to grips with this problem!!!!
As and when you have found the root cause of the problem, I shall very interested to know what it was.
Kindest regards,
Douglas

pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, Nova Scotia, Canada   CAN
I can't tell where the sound is coming from in a video but it sounds like an old hard, fan belt slapping. Cheap to check... just slip the belt off and fire her up.

Adrian



Home built Eaton M62 Supercharger with 9psi boost, "stock" high ratio rocker arms, 8:1 compression, Piper 270 cam, ported head, matched manifolds, CB Performance computerized ignition.

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EMW540D Roy Nolder
UK   GBR
Hello Martin,

That noise seems to have an overrun when you ease off the fuel. That looks like a viscous-coupled fan. Is the noise coming from that?

steve12955 Steve B
Massachusetts, USA   USA
1970 MG MGB "Emma"
Still sounds like excessive valve lash. Noise seemed to lessen when feeler gauge was placed under first (exhaust) and fifth (exhaust) rockers. I believe springs were renewed but that would be my opinion.

Southdpwns Martin Koronka
Arundel, West Sussex, UK   GBR
It's a fixed, plastic fan.

In reply to # 3494833 by EMW540D Hello Martin,

That noise seems to have an overrun when you ease off the fuel. That looks like a viscous-coupled fan. Is the noise coming from that?



Currently MGB GT, 73
Two midgets
Morris Minor
VW Camper van
Morris 1300

LowCarbs Thomas W
Boston, MA, USA   USA
1977 MG MGB
Good video. "Very little oil pressure" is an interesting statement. I've never run an MG engine with the cover off, but is it typical for it to be so dry in the valvetrain area?

If you run an engine momentarily without oil pressure (like when you change the oil and replace the oil filter), it does make quite a clatter until oil pressure reaches the various areas. Could this be what you are hearing?

The picture below comes from this post.


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tigger00 Rick O
Creedmoor, North Carolina, USA   USA
1974 MG MGB "Queenie"
1974 MG MGB
I think at this point I would pull the springs back off and look for worn valve guides

MRoadster Avatar
MRoadster Gold Member Jim Wulf
Doylestown, PA, USA   USA
1938 MG TA Tickford "The TA"
1963 Ford Thunderbird "The M Car"
1967 MG MGB MkI "The B"
I believe Martin stated "very good oil pressure", not "little oil pressure". It's a little difficult to hear clearly over the racket from the tappets. The relatively small amount of oil in the valve train while running is typical of these engines, as compared to an American V8 like a Chevy 350 where oil is spurting all over the place.

Look at the video in Youtube and slow it down to .25 speed. Is there something different/irregular in the movement of one of the valves as compared to the others?

In reply to # 3494851 by LowCarbs Good video. "Very little oil pressure" is an interesting statement. I've never run an MG engine with the cover off, but is it typical for it to be so dry in the valvetrain area?

If you run an engine momentarily without oil pressure (like when you change the oil and replace the oil filter), it does make quite a clatter until oil pressure reaches the various areas. Could this be what you are hearing?

The picture below comes from this post.

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