Too much cam noise?
Discussion
So it just goes from bad to worse really.
I decided to go for the used clatter cams & a set of new followers to run with them.
It was not a good feeling taking out the other good cam that looked like this:
I'd also gone to a lot of trouble to get the clearances spot on for them 400 miles ago.
But there was only one way forward so I set the clearances again on the clatter cams & new followers, this now being the third time I've done it in 400 miles (the first time it only ran a few hundred yards before the valve stuck in the new guide & the heads had to come off again). I didn't try to get them bang on this time as I figured the new followers would wear slightly as they bedded in. I've now got a collection of shims big enough to get them with in a few thou with out grinding, but still needing to swap from one side to the other.
So I fitted the cam covers back on with just what was left of the old sealant left on them & ran it at a fast idle of 2k for five mins, it sounded good, much quieter than before & very little oil leaked which was nice, the last time I tried to do that there was no sealant & it made a right mess!
A quick check of the clearances showed most had indeed increased by 1 thou, but there were some ominous looking marks on the new followers. On removing the clatter cams I found this:
Just what I wanted to find....
As Plastic man pointed out way back in this thread it looks like they aren't spinning properly. I checked the new followers could rotate as just as easily as my old ones & the most, four in total, were marked on the side that had the perfectly good cam & followers removed from so all I can think is the cam lobes have been damaged some how some where & are not pressing down flat on the follower so not letting it spin correctly.
So it seemed the only option was for new cams, the supplier agreed to give the 100 quid back for the "good" used clatter cam & give a 20% discount on a pair of new cams. And delightfully I get a fourth time of setting the clearances from scratch in 400 miles
I would be more annoyed but I realised after a heart stopping ten minutes of franticly searching for a dropped nut I was sure I'd heard fall down the cam cover, things can still get a lot worse...
With nothing left to do to the car I finally found a bit of time to catch up with some TV with the kids off to bed their mess tided up & my better half away I was too tired for babe station so thought I catch up with some Wheeler Dealers that's been waiting for weeks to watch on the box. Whats the first thing Ed does to the (lovely) 240Z but pull out the cam, I almost laugh till I see what they do to it - weld new metal to the tips & re-grind it FFS lots of banghead emojis. Why hadn't I watched that before I pulled the other good cam out?!
I'm not sure if it's possible to weld to Sintered cams (I think the first two types of cam were that), not sure if I want to know now!
But the clatter cams I've got that are clearly of no use in the state they are in could well be grindable. There isn't large amounts of material missing, though they did seem to leave some on the followers as they cleaned up ok.
However I'm fed up trying different things now I just want something that will work & I think now chill cast cams would be best for that.
Also if it ever actually gets running again I'd like to get it properly mapped & if the cam is questionable with a chance of needing replacing with one of a different profile it's not going to work so well with that custom map.
I decided to go for the used clatter cams & a set of new followers to run with them.
It was not a good feeling taking out the other good cam that looked like this:
I'd also gone to a lot of trouble to get the clearances spot on for them 400 miles ago.
But there was only one way forward so I set the clearances again on the clatter cams & new followers, this now being the third time I've done it in 400 miles (the first time it only ran a few hundred yards before the valve stuck in the new guide & the heads had to come off again). I didn't try to get them bang on this time as I figured the new followers would wear slightly as they bedded in. I've now got a collection of shims big enough to get them with in a few thou with out grinding, but still needing to swap from one side to the other.
So I fitted the cam covers back on with just what was left of the old sealant left on them & ran it at a fast idle of 2k for five mins, it sounded good, much quieter than before & very little oil leaked which was nice, the last time I tried to do that there was no sealant & it made a right mess!
A quick check of the clearances showed most had indeed increased by 1 thou, but there were some ominous looking marks on the new followers. On removing the clatter cams I found this:
Just what I wanted to find....
As Plastic man pointed out way back in this thread it looks like they aren't spinning properly. I checked the new followers could rotate as just as easily as my old ones & the most, four in total, were marked on the side that had the perfectly good cam & followers removed from so all I can think is the cam lobes have been damaged some how some where & are not pressing down flat on the follower so not letting it spin correctly.
So it seemed the only option was for new cams, the supplier agreed to give the 100 quid back for the "good" used clatter cam & give a 20% discount on a pair of new cams. And delightfully I get a fourth time of setting the clearances from scratch in 400 miles
I would be more annoyed but I realised after a heart stopping ten minutes of franticly searching for a dropped nut I was sure I'd heard fall down the cam cover, things can still get a lot worse...
With nothing left to do to the car I finally found a bit of time to catch up with some TV with the kids off to bed their mess tided up & my better half away I was too tired for babe station so thought I catch up with some Wheeler Dealers that's been waiting for weeks to watch on the box. Whats the first thing Ed does to the (lovely) 240Z but pull out the cam, I almost laugh till I see what they do to it - weld new metal to the tips & re-grind it FFS lots of banghead emojis. Why hadn't I watched that before I pulled the other good cam out?!
I'm not sure if it's possible to weld to Sintered cams (I think the first two types of cam were that), not sure if I want to know now!
But the clatter cams I've got that are clearly of no use in the state they are in could well be grindable. There isn't large amounts of material missing, though they did seem to leave some on the followers as they cleaned up ok.
However I'm fed up trying different things now I just want something that will work & I think now chill cast cams would be best for that.
Also if it ever actually gets running again I'd like to get it properly mapped & if the cam is questionable with a chance of needing replacing with one of a different profile it's not going to work so well with that custom map.
Edited by Luckyone on Saturday 13th June 10:57
ukkid35 said:
I save reading your posts for when I'm so depressed about the state of my car that I need reassurance that things are not that bad.
Seriously though, I admire your perseverance and I wish you well. I doubt there is anything I could offer in terms of help or advice, but if you think there is don't hesitate to ask.
Seriously though, I admire your perseverance and I wish you well. I doubt there is anything I could offer in terms of help or advice, but if you think there is don't hesitate to ask.
thanks 
Just waiting for the new cams to turn up now apparently the new chill cast cams have never casued any problems so fingers crossed. I was speaking to a chap called Jason at a place that knows a thing or two about AJPs. He said he has always set the clearances at 7 & 11, from memory that's what the book said. (Thats not Jason at str8six BTW)
I'm fairly sure Jools said he's tested & found 10 & 12 give just the same power but better emissions.
For the cam timing equal on overlap will give the best power, but if I want it a bit more drivable at low revs setting the inlet 1mm lower would make it nicer at the expense of a little top end power. That should be quite easy to test for my self (though I had to jump the cam sprockets when fitting the clatter cam to get it line up as the bolt holes were in a different place - that made me nervous!) He said it would still be the case with the short pipes it's running, though they do of course rob a bit from the bottom end anyway.
So shall I go with 10 & 12 or what the man said of 7 & 11 (he said he'd do it the same for any of the cams).
Or any opinions on clearances & cam timing?
It will be spending more time at low revs with kids in the back so I may well give that a go.
Victor Meldrew's words of I DO NOT BELIEVE IT echoed round my head upon the latest in instalment.
It turns out I was misinformed by a trusted independence source, the latest chill cast cams DO have exactly the same profile as our old non hex drive cams, so all I ever really needed was one new cam to replace the damaged old one. Instead I've wasted loads of time pulling the perfectly good cam with spot on clearances & mucking about with the pair of bad second hand clatter cams.
(It is of course possible there have been 4 types of cam, with one older "new" type that did have a different profile.)
I of course double checked with the cam supplier / TVR engine builder that I did need to buy two new cams & the new ones were not a match for our original, a lot of good that did!
This is the pic I posted a page or so back where I took a cast of our original non hex drive cam:
Taken just to be sure the one free clatter cam I was sent was different:
That same cast fitted the new chill cast cam perfectly:
The measurement from the base of the lobe to the tip was exactly the same too. (The clatter cam only being slightly different there, but the lobe is much fatter)
I was trying to get it fixed with out having to spend any more money as I hadn't done anything to cause any of the issues other than listen to the machine shop say "it will be fine". But when we gave up on that & started spending money the option of the pair of used clatter cams with new followers, would have been much the same as one new cam with 8 followers & I would have only had to do one half of the engine. As it is I've already ground some of the shims I now need again
So I'm putting the perfectly good cam & followers back in as there really is nothing wrong with them along with the one new chill cast cam & 8 new followers, unless any one can give me a good reason not to!
Now to the really interesting bit for anyone else, when put I back in the two now identical profiled cams the new cam with it's new followers needed significantly thicker shims than the other side with its (matched very good) original followers. A little bothered by this I then checked the thickness of the new followers, they were on average between 105 & 107 thou where as our old ones were all 111 thou to with in less than 1 thou. Oddly though I found one new one was 98 thou. So if you happen to have one valve that is getting to close to the minimum shim thickness this follower could keep you going for quite some time.
I'm going to return the other new cam, but could hold on to the thin follower/s if anyone thinks it / they could be of use to them?
To come full circle some may remember how I actually ended up in all this mess with a non running Cerb getting on for getting on for two years now, because I found I needed a shim that was less than the thinnest
On that note a quick recap:
The engine had always been a great runner, had never given any problems but was out anyway as I'd done a full body off rebuild, so finding it needed a shim that was too thin seemed like a good reason to whip the heads off & fit new inlet valves. Only when it was in bits I found the exhaust guides were badly melted, so the head had to go off for new exhaust guides. I was told I should really fit new exhaust valves, but as the old ones were in top shape the machine shop couldn't give a good reason why so it was agreed I'd keep the old exhaust valves. But on the first very short test run one of the exhaust valves stuck. So engine back out, heads back off & off to the machine shop again, then they remembered that when they were testing their new cast iron guides they did have some problems with the original stainless valves, so did all the re-machine for nothing & threw in a new set of coated exhaust valves. As I was still doing shift work I didn't mind wasting lot's of paid days off putting it all back again.
The really annoying bit starts with this thread, as the time of the second lot of machine work I was worried about the state of the tip of the cam from that stuck valve & asked about it but was told "it would be fine". As it goes those same crap shims with all the lips inside also came from the same place, they also waisted me a lot of time.
Still hopefully after the next batch of new shims turn up (I now need thicker ones) they will be good ones & it may possibly be running again...
It turns out I was misinformed by a trusted independence source, the latest chill cast cams DO have exactly the same profile as our old non hex drive cams, so all I ever really needed was one new cam to replace the damaged old one. Instead I've wasted loads of time pulling the perfectly good cam with spot on clearances & mucking about with the pair of bad second hand clatter cams.
(It is of course possible there have been 4 types of cam, with one older "new" type that did have a different profile.)
I of course double checked with the cam supplier / TVR engine builder that I did need to buy two new cams & the new ones were not a match for our original, a lot of good that did!
This is the pic I posted a page or so back where I took a cast of our original non hex drive cam:
Taken just to be sure the one free clatter cam I was sent was different:
That same cast fitted the new chill cast cam perfectly:
The measurement from the base of the lobe to the tip was exactly the same too. (The clatter cam only being slightly different there, but the lobe is much fatter)
I was trying to get it fixed with out having to spend any more money as I hadn't done anything to cause any of the issues other than listen to the machine shop say "it will be fine". But when we gave up on that & started spending money the option of the pair of used clatter cams with new followers, would have been much the same as one new cam with 8 followers & I would have only had to do one half of the engine. As it is I've already ground some of the shims I now need again
So I'm putting the perfectly good cam & followers back in as there really is nothing wrong with them along with the one new chill cast cam & 8 new followers, unless any one can give me a good reason not to!
Now to the really interesting bit for anyone else, when put I back in the two now identical profiled cams the new cam with it's new followers needed significantly thicker shims than the other side with its (matched very good) original followers. A little bothered by this I then checked the thickness of the new followers, they were on average between 105 & 107 thou where as our old ones were all 111 thou to with in less than 1 thou. Oddly though I found one new one was 98 thou. So if you happen to have one valve that is getting to close to the minimum shim thickness this follower could keep you going for quite some time.
I'm going to return the other new cam, but could hold on to the thin follower/s if anyone thinks it / they could be of use to them?
To come full circle some may remember how I actually ended up in all this mess with a non running Cerb getting on for getting on for two years now, because I found I needed a shim that was less than the thinnest
On that note a quick recap:
The engine had always been a great runner, had never given any problems but was out anyway as I'd done a full body off rebuild, so finding it needed a shim that was too thin seemed like a good reason to whip the heads off & fit new inlet valves. Only when it was in bits I found the exhaust guides were badly melted, so the head had to go off for new exhaust guides. I was told I should really fit new exhaust valves, but as the old ones were in top shape the machine shop couldn't give a good reason why so it was agreed I'd keep the old exhaust valves. But on the first very short test run one of the exhaust valves stuck. So engine back out, heads back off & off to the machine shop again, then they remembered that when they were testing their new cast iron guides they did have some problems with the original stainless valves, so did all the re-machine for nothing & threw in a new set of coated exhaust valves. As I was still doing shift work I didn't mind wasting lot's of paid days off putting it all back again.
The really annoying bit starts with this thread, as the time of the second lot of machine work I was worried about the state of the tip of the cam from that stuck valve & asked about it but was told "it would be fine". As it goes those same crap shims with all the lips inside also came from the same place, they also waisted me a lot of time.
Still hopefully after the next batch of new shims turn up (I now need thicker ones) they will be good ones & it may possibly be running again...
Not wishing to jump the boat, but I think I've got a running Cerb again. Tests in one of our fields went well, the kids loved the power slides & I was pleased to find that dry grass when cut nice & short can take quite a lot of punishment so we had quite a few more laps
What was wrong with your drivers side cam?
Jimm218 said:
That is quite a tale. Giving me the fear as I may have to go through this in the future. I could certainly make use of a follower that was thinner and would allow me to run for longer. I don't recall how thick mine were unfortunately. I'm also looking for a drivers side cam. Mine have the hex drive on them so I think that might make them caller cams? But really confused on that!
If you have cams that are nice & smooth all over & have hex drives on then you have got clatter cams. If they have hex drives but are rough as hell between the lobs then they are the new chill cast ones. What was wrong with your drivers side cam?
Tanguero said:
I am down for Millbrook - looking forward to seeing what the 4.7 will do!
That will be interesting to see! There was something about testing your car up to 100mph, I hope that's not the speed limit or it could be a bit tame, unless it very twisty. Or kids are very excited to see our "racing car" on the racing track, it's been a garage ornament for just about all their lives so far & the older one on is 5 now!
I've been a bit distracted my other half's nice cars again:
Still that's gone now & not really missed all that much, funny how you can have a fast car that's not fun to drive!
So back to the Cerb, I'm glad to say it's still sounds lovely with no more nasty noises
The ECU is playing tricks now but that's for a different thread.
If you haven't read though the rest of the this old thread, lets just say I've got lots of AJP8 cams!
In the end I got two new chill cast cams, but when I found they were the same as the old cams I had in it to start with (as far as profile went) I just put my good old cam back in with the other new one. Some time later rang up to say I wanted to send the other new one back, the Cerb was back together & running well by this point, my supplier then told me that although the profile of the lobes was the same they had phasing tweaked on the new chill cast cams so I had miss matched cams after all. But he said if it was running ok I should just forget about it & send the cam back.
I didn't really like the idea of it not being right after spending so much time on it, but couldn't face stripping it down again. So as it was running I just left it.
Then recently it occurred to me I had the ideal checking took doing noting tucked away in the work shop I'm slowly building:
It's not in use yet so don't diss me for the state of it but please do point out any flaws in my logic for checking the phasing of the cams.
I had first checked my old duff cam (no pics of that being checked but it was the same way) I marked the pulley wheel of the lathe where the DTI showed the cam lobe was at its peak & the body of lathe at the same point. Then I checked the other lobe for that cylinder & marked the pulley where it lined up with my mark on the lathe body. To be sure I lined up my marks again & rotated the cam in the chuck so it was at peak for a different cylinder, then rotated it all to check the other mark & they matched perfectly.
So then I swapped to the new chill cast cam (the pics). This time I made a new mark on the body of the lathe when the lobe came to the peak, I then rotated it all so the other lobe was at its peak for the same cylinder, the second mark I'd made on the pulley wheel for the other cam lined up perfectly with the new mark I'd made for this cam.
So the marks on the lathes pulley wheel show the exact distance between the lobes for one cylinder & they match exactly for both my old cam & the new chill cast
So if the size of the lobes is exactly the same, the lobe shape is exactly the same & the phasing for one cylinder is exactly the same, as far a the engine can see they are the same right?
Still that's gone now & not really missed all that much, funny how you can have a fast car that's not fun to drive!
So back to the Cerb, I'm glad to say it's still sounds lovely with no more nasty noises
The ECU is playing tricks now but that's for a different thread.
If you haven't read though the rest of the this old thread, lets just say I've got lots of AJP8 cams!
In the end I got two new chill cast cams, but when I found they were the same as the old cams I had in it to start with (as far as profile went) I just put my good old cam back in with the other new one. Some time later rang up to say I wanted to send the other new one back, the Cerb was back together & running well by this point, my supplier then told me that although the profile of the lobes was the same they had phasing tweaked on the new chill cast cams so I had miss matched cams after all. But he said if it was running ok I should just forget about it & send the cam back.
I didn't really like the idea of it not being right after spending so much time on it, but couldn't face stripping it down again. So as it was running I just left it.
Then recently it occurred to me I had the ideal checking took doing noting tucked away in the work shop I'm slowly building:
It's not in use yet so don't diss me for the state of it but please do point out any flaws in my logic for checking the phasing of the cams.
I had first checked my old duff cam (no pics of that being checked but it was the same way) I marked the pulley wheel of the lathe where the DTI showed the cam lobe was at its peak & the body of lathe at the same point. Then I checked the other lobe for that cylinder & marked the pulley where it lined up with my mark on the lathe body. To be sure I lined up my marks again & rotated the cam in the chuck so it was at peak for a different cylinder, then rotated it all to check the other mark & they matched perfectly.
So then I swapped to the new chill cast cam (the pics). This time I made a new mark on the body of the lathe when the lobe came to the peak, I then rotated it all so the other lobe was at its peak for the same cylinder, the second mark I'd made on the pulley wheel for the other cam lined up perfectly with the new mark I'd made for this cam.
So the marks on the lathes pulley wheel show the exact distance between the lobes for one cylinder & they match exactly for both my old cam & the new chill cast
So if the size of the lobes is exactly the same, the lobe shape is exactly the same & the phasing for one cylinder is exactly the same, as far a the engine can see they are the same right?
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