How much tappet noise is normal?
Discussion
I'm a newbie Chimaera owner - had it just a few months now and loving it. It's a '99 450 with about 57,000 on the clock. As far as I know the engine is unmodified, and I don't believe it's had a new cam or other bottom-end work done.
I'm beginning to wonder how much tappet noise can be considered normal on this engine at this mileage. Mine produces a light tappet noise, which is audible from inside the car and also if you stick your head underneath the car - but it's not particularly noticeable if you listen from above the engine. The noise is there once the engine is warmed up; less so when it's cold. It's only noticeable when the engine's ticking over or at light load.
To be honest the noise doesn't really bother me, but I'd like to know whether a light tappet sound is normal or whether the tappets should be silent.
Looking at the invoice for its last service (in August), it has "5W-40" scribbled on it, so I assume that's the oil it has in it. Would it benefit from a slightly heavier oil during its next service - perhaps a 10W-50 like this?
Or should I just not worry about it?
__
David
I'm beginning to wonder how much tappet noise can be considered normal on this engine at this mileage. Mine produces a light tappet noise, which is audible from inside the car and also if you stick your head underneath the car - but it's not particularly noticeable if you listen from above the engine. The noise is there once the engine is warmed up; less so when it's cold. It's only noticeable when the engine's ticking over or at light load.
To be honest the noise doesn't really bother me, but I'd like to know whether a light tappet sound is normal or whether the tappets should be silent.
Looking at the invoice for its last service (in August), it has "5W-40" scribbled on it, so I assume that's the oil it has in it. Would it benefit from a slightly heavier oil during its next service - perhaps a 10W-50 like this?
Or should I just not worry about it?
__
David
Edited by dmjw01 on Monday 24th January 09:32
Just to add another angle on tappet noise, when I bought mine I asked The TVR Center about certain common noises incase I encountered any...they couldn't remember the last time they had one in with a missing rocker pad. Not saying it doesn't happen because it clearly does (as above post proves) but imo if the car feels good then the noise is most likely exh gaskets or the 4 into 1 joint.
For it to be a lifter and cam you'd be pretty down on power if the lifter was that noisy. I had a lobe wiped off my old Dodge 440 (7.2! haha) three lifters were totally ruined, you could feel the knocking through the throttle pedal!
For it to be a lifter and cam you'd be pretty down on power if the lifter was that noisy. I had a lobe wiped off my old Dodge 440 (7.2! haha) three lifters were totally ruined, you could feel the knocking through the throttle pedal!
Hmmm... food for thought already!
I've just been searching P/H to find out more about the rocker pad issue, and it does sound similar. My tapping sound is quite slow - perhaps 5 to 10 taps per second, depending on engine speed. This suggests to me that it could indeed be just one rocker, although it would also fit with a leaking manifold gasket. It's definitely a "tap-tap-tap-tap-tap-tap...." rather than a rattle, if you see what I mean. My impression was that the noise comes more from the bottom than the top - but I need to check this, and also try to determine if it comes from just one side.
__
David
I've just been searching P/H to find out more about the rocker pad issue, and it does sound similar. My tapping sound is quite slow - perhaps 5 to 10 taps per second, depending on engine speed. This suggests to me that it could indeed be just one rocker, although it would also fit with a leaking manifold gasket. It's definitely a "tap-tap-tap-tap-tap-tap...." rather than a rattle, if you see what I mean. My impression was that the noise comes more from the bottom than the top - but I need to check this, and also try to determine if it comes from just one side.
__
David
Edited by dmjw01 on Monday 24th January 10:33
When I took delivery of my car it had just been serviced by a well known Cambridgeshire TVR specialist, the oil was clearly new when the dip stick was inspected.
After a couple of thousand miles I had a very slight tapping noise when hot, I phoned the TVR specialist to see what oil they used and was proudly told they only use Shell Helix 5/40W
A TVR with a RV8 runs quite hot so it is equally quite hard on it's oil, lets face it the design is 50 years old from the days when engine tolerances demanded heavier oils.
Its also likely most of our cars have done a few miles by now, so its wise to move up a grade to limit oil consumption and hydraulic tappet bleed down.
I either run Millers CSS 20W50 or Penrite HPR 15W60, when running these oils the slight tapping noise is completely eliminated.
Both contain zinc which has been removed from most modern oils on environmental grounds, zinc is an essential additive for flat tappet engines like the RV8.
Both have a good SAE rating so are very high quality oils, and both are semi-synthetic which is ideal for the RV8.
In my experience anything lighter than a 15W50 is definitely not a good idea in an RV8 that's done 30,0000 miles or more.
If you do use a lighter oil be prepared to hear tapping from the cam followers when it gets hot.
If you run your RV8 on an oil without zinc in it be prepared to replace the cam and followers every 40,000 miles or less.
After a couple of thousand miles I had a very slight tapping noise when hot, I phoned the TVR specialist to see what oil they used and was proudly told they only use Shell Helix 5/40W
A TVR with a RV8 runs quite hot so it is equally quite hard on it's oil, lets face it the design is 50 years old from the days when engine tolerances demanded heavier oils.
Its also likely most of our cars have done a few miles by now, so its wise to move up a grade to limit oil consumption and hydraulic tappet bleed down.
I either run Millers CSS 20W50 or Penrite HPR 15W60, when running these oils the slight tapping noise is completely eliminated.
Both contain zinc which has been removed from most modern oils on environmental grounds, zinc is an essential additive for flat tappet engines like the RV8.
Both have a good SAE rating so are very high quality oils, and both are semi-synthetic which is ideal for the RV8.
In my experience anything lighter than a 15W50 is definitely not a good idea in an RV8 that's done 30,0000 miles or more.
If you do use a lighter oil be prepared to hear tapping from the cam followers when it gets hot.
If you run your RV8 on an oil without zinc in it be prepared to replace the cam and followers every 40,000 miles or less.
Edited by Chimpafrolic on Monday 24th January 12:43
crackedfinger said:
Just to add, when it was a pad missing form a rocker, using a screwdriver as a 'hearing aid' I was pretty certain it was in the rocker area rather than the exhaust. May help rule out the rockers in your case.
A length of heater hose or similar is excellent to detect, (in my case a leaking exhaust manifold gasket)any tapping noises.Chances are, it won't be more serious then the exhaust gasket, very common.
In normal cases if its an exhaust leak it will be louder when it is cold, it will also be more noticible when the car is under load, they do normally quiet themselves down though when they get warm and expand, if a rocker pad has fallen off the noise will be there all the time allthough as the drivetrain expands you will loose what little preload you have left so will be more noticible when warm, same goes if you have a worn cam/follower, the other possibilites that become louder when the engine has warmed up is wear between piston pin and piston, and a cylinder liner moving.
Rob
Rob
This is how mine sounded when the manifold gasket went.
http://redirectingat.com/?id=1044X509854&xs=1&...
http://redirectingat.com/?id=1044X509854&xs=1&...
I have a 1998 450 with similar mileage and from the way you describe it similar noise. The very well respected independent TVR specialist who services my car told me that the 450 is a noisy engine anyway when compared to the 400 or 500. He also suggested that I should get the car dyno tested as this would show up any camshaft wear or lean running due to gasket leaks. I duly had the car tested and it was producing a very healthy 260.7 bhp with good torque curve and no evidence of leaks. The tester suggested, as others here have done, that 5/40 was too thin an oil and the engine would benefit from a thicker one. I intend to discuss this with the specialist when next the car goes for service.
My point is that I would hesitate to assume the camshaft is worn. A replacement camshaft is not a cheap option and you may find that the original is not that worn after all.
Definitely worth checking for exhaust gasket leaks too.
I hope this helps.
PVN
My point is that I would hesitate to assume the camshaft is worn. A replacement camshaft is not a cheap option and you may find that the original is not that worn after all.
Definitely worth checking for exhaust gasket leaks too.
I hope this helps.
PVN
As far as the way the lifters, rods & rockers work, it's the same engine. Bit of waffle I suspect there. 
I'm just passing on what I was told - I don't profess to be an expert. However, the said well respected independent TVR specialist, whose opinion I respect, could have told me I needed a new camshaft when clearly I didn't. That would have been waffle (at the very least). I respect his honesty and his knowledge of TVRs, especially the RV8 engines. Why would he lie??
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