New cam now fitted still some tappet noise.....
Discussion
I have now fitted a new MC1 cam, new lifters, springs, duplex timing set, and rocker gear over the weekend. All went well - only problem I had was difficulty in removing the Y piece (took about an hour alone - ended up having to pull the whole system back an inch for clearance).
The old cam was a TVR 51, which I assume is the original one (car has done 75k) two of the lobes were worn down by 2mm!
I have now run in the new cam (20 mins at about 2500rpm). The tappet noise is a lot quieter than with the old cam, but there is still something there - maybe I am just being paranoid! Is this 'normal' are they all a bit 'tapperty'?
Performance is also better through the rev range..
Cheers Toby.
P.S. I also set the preloads with shims under the rocker posts.
The old cam was a TVR 51, which I assume is the original one (car has done 75k) two of the lobes were worn down by 2mm!
I have now run in the new cam (20 mins at about 2500rpm). The tappet noise is a lot quieter than with the old cam, but there is still something there - maybe I am just being paranoid! Is this 'normal' are they all a bit 'tapperty'?
Performance is also better through the rev range..
Cheers Toby.
P.S. I also set the preloads with shims under the rocker posts.
Eo66 said:
Do you get the tappety rattle type noise after you have rev'd the engine just as the rev's settle ?
I'll check later - what would this mean, as opposed to tapping all the time?
I did not fit a cam retaining plate as there wasn't one on there in the first place (although the tappings were in the block).
Nuggs said:
I have a slight ticking noise, which is apparently the result of having my precats taken out. It's been confirmed that the tappets and manifold gaskets are fine... Could it be the same for you?
I've still got the pre-cats in mine - so don't think it could be this, although the drivers side one seems to have moved down the manifold towards the Y piece more than the passenger side one!
It could be the belt tensioner - the bearing in it felt a bit 'rough' when I took it off - I will need to run the engine without the belt to test it.
Eo66 said:
Do you get the tappety rattle type noise after you have rev'd the engine just as the rev's settle ?
My Chim 500 does this and had a full engine refresh 3K miles ago, I was told it was to do with the tolerance in the little ends and some do it and some dont, whats yoour diagonsis?
Just had a listen after I got back from work. The noise just seems to be general valve train clatter - it does not seem to be a single lifter or rocker - this I assume would be noticable as a lower frequency tapping. Seems to be making the same noise all the time, not just after reving the engine.
It IS quiter than before I changed the cam, however it does not seem as smooth as I was expecting........ Perhaps I was expecting too much and I'm just being a bit paranoid!
I think I'm going to leave it a while and then maybe check the preload again.
Toby
It IS quiter than before I changed the cam, however it does not seem as smooth as I was expecting........ Perhaps I was expecting too much and I'm just being a bit paranoid!
I think I'm going to leave it a while and then maybe check the preload again.
Toby
Just done the same thing, and I still have some tappet noise. Its a hell of a lot quieter than it was though.
I think its too easy to get a bit paranoid about these engines, after all some valve train clatter is to be expected in a 40 year old engine design. Setting the pre load accurately would help, but after spending 3 days with my head in an engine, and after some expert advice I gave up!
I think its too easy to get a bit paranoid about these engines, after all some valve train clatter is to be expected in a 40 year old engine design. Setting the pre load accurately would help, but after spending 3 days with my head in an engine, and after some expert advice I gave up!
I'm using Magnitec 10w-40. This should be OK for the lifters as its ticker than the Mobil 1 water!
I'm now thinking the noise could be due to the new rocker assemblies I have fitted. These have new steel rockers and shafts, but when I assembled them I noticed that the machined holes for the pushrods did not look the same depth on all the rockers (they were 'Britpart' parts). This made setting the preload an average over the lifters. I think I may take the rocker covers off and put the old assembiles back on and see what it sounds like (the old assemblies were not too worn anyway).
Question is, do I also take out the shims I have put under the rockers? I know this will cause the pre-load to be out, but I suppose it will anyway with the different rockers? If I am correct, the only reason for setting the preload to about 0.5mm is to reduce the risk of lifter pump up at high revs?
Ultimatly I think will have to take the inlet off again and reset the preload, with a new set of decent rockers..... just haven't got the time at the moment...
I'm now thinking the noise could be due to the new rocker assemblies I have fitted. These have new steel rockers and shafts, but when I assembled them I noticed that the machined holes for the pushrods did not look the same depth on all the rockers (they were 'Britpart' parts). This made setting the preload an average over the lifters. I think I may take the rocker covers off and put the old assembiles back on and see what it sounds like (the old assemblies were not too worn anyway).
Question is, do I also take out the shims I have put under the rockers? I know this will cause the pre-load to be out, but I suppose it will anyway with the different rockers? If I am correct, the only reason for setting the preload to about 0.5mm is to reduce the risk of lifter pump up at high revs?
Ultimatly I think will have to take the inlet off again and reset the preload, with a new set of decent rockers..... just haven't got the time at the moment...
Hi,
just gone through the same exercise on my Griffith. Maybe woth checking all your exhaust manifold bolts, mine needed nipping up after a few runs, definately cured a slight tapping noise that developed. Apart from that, new cam and lifters (with original rockers)elimated the noisey top end, no surprise 14 of the 16 lobes were worn, several by 2 - 3 mm.
just gone through the same exercise on my Griffith. Maybe woth checking all your exhaust manifold bolts, mine needed nipping up after a few runs, definately cured a slight tapping noise that developed. Apart from that, new cam and lifters (with original rockers)elimated the noisey top end, no surprise 14 of the 16 lobes were worn, several by 2 - 3 mm.
groomvroom said:
Eo66 said:
Do you get the tappety rattle type noise after you have rev'd the engine just as the rev's settle ?
My Chim 500 does this and had a full engine refresh 3K miles ago, I was told it was to do with the tolerance in the little ends and some do it and some dont, whats yoour diagonsis?
After having the work done it was silent, but it recently started to make this rattle after you rev just as the rev settle, i have took it back to my indie to have a look,will keep you informed.
Eo66 said:
groomvroom said:
Eo66 said:
Do you get the tappety rattle type noise after you have rev'd the engine just as the rev's settle ?
My Chim 500 does this and had a full engine refresh 3K miles ago, I was told it was to do with the tolerance in the little ends and some do it and some dont, whats yoour diagonsis?
After having the work done it was silent, but it recently started to make this rattle after you rev just as the rev settle, i have took it back to my indie to have a look,will keep you informed.
Mine does that but only every so often. I reckon it is a sticky lifter picked up by Levens at the 12k service in January. It seems to be OK at the moment but I may get the oil changed to something thicker to see if that helps. Been told that a sticky lifter isn't a major problem but if it returns and gets louder then will probably need to have it looked at
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