Trying to keep H.M.S. Morale afloat!
Discussion
The fun and games begin! Those who know me will know since I rebuilt the S1, I've had issues with a rattly engine. Not normal-for-an-old-Cologne-rattly. Rattly like, horribly rattly. Drives fine, behaves fine, sounds bloody awful!
Having checked the valve clearances about 5,302 times now, I'm into the next stage; I fitted a solid alloy cam gear set, and a Piper BP270 fast road cam when I rebuilt the engine. I've heard from other people who believe one or the other can cause the horrible noise. Matey from Tickover seemed to think the Piper cams have an aggressive 'off' ramp, which is why they preferred Kent. Other people said the alloy pulley was fine, it's just the steel one that whines a bit. Others said 'oh no, the alloy ones chatter like buggery'! It is a chattering noise that I've got, in fairness.
So, I am now into the realms of stripping down the front of the car, to change the alloy gear back to a used standard one, just to see if it makes a difference. If it doesn't, I have to take it all apart again to change the camshaft for a standard one, and there's no guarantee that will cure it either! And.....there is the chance that the crank gear will also need changing - the steel pulley works with the original crank gear, but the alloy one came with a replacement, which I fitted. Now I don't know whether the replacement was needed because, alloy being softer than steel, it needs a new surface to bed in against, or because the pitch of the helical gears is different. If it does turn out to be different, I'll need to drop the sump off to change that too, just to see if my noise goes away, and that means either removing the engine (no thanks) or cutting the lower brace and modifying it to be a removable one (more likely). And that, boys and girls, is why I've been in a grump with my S for over a year - all this work, and I might still have to live with a horrible chattering noise!
Having checked the valve clearances about 5,302 times now, I'm into the next stage; I fitted a solid alloy cam gear set, and a Piper BP270 fast road cam when I rebuilt the engine. I've heard from other people who believe one or the other can cause the horrible noise. Matey from Tickover seemed to think the Piper cams have an aggressive 'off' ramp, which is why they preferred Kent. Other people said the alloy pulley was fine, it's just the steel one that whines a bit. Others said 'oh no, the alloy ones chatter like buggery'! It is a chattering noise that I've got, in fairness.
So, I am now into the realms of stripping down the front of the car, to change the alloy gear back to a used standard one, just to see if it makes a difference. If it doesn't, I have to take it all apart again to change the camshaft for a standard one, and there's no guarantee that will cure it either! And.....there is the chance that the crank gear will also need changing - the steel pulley works with the original crank gear, but the alloy one came with a replacement, which I fitted. Now I don't know whether the replacement was needed because, alloy being softer than steel, it needs a new surface to bed in against, or because the pitch of the helical gears is different. If it does turn out to be different, I'll need to drop the sump off to change that too, just to see if my noise goes away, and that means either removing the engine (no thanks) or cutting the lower brace and modifying it to be a removable one (more likely). And that, boys and girls, is why I've been in a grump with my S for over a year - all this work, and I might still have to live with a horrible chattering noise!
Shims? It is a 2.8 Cologne? No shims.
Richard, when you fitted the fast road cam did you change the valve springs? If not then valve bounce might be an issue? Wouldnt appear at low revs though.
I'm not a fan of solid cam gears on these engines. Unlike the old Essex engine the composite gear teeth do not break up, unless there has been other mechanical damage in the engine. These cam drive gears are fairly simple angle cut rather than truely helical gears and they do not give the nice gradual engagement that a true helical gear would. Have a look at them. Being cut at an angle they also cause an end thrust which will magnify any end float in the cam itself. The reason Ford went to the trouble of using a composite gear is that the metal to metal ones cut this way are bloody noisy!
You know that, as you turn the engine over against the valves (plugs out) there is some variation in resistance as each valve spring is compressed or released. That causes differences in pressure on the cam, and differences in pressure on the cam wheel/cam drive wheel interface. The composite gear actually takes pressure variations on both sides of the tooth and pretty well deals with what would otherwise be chatter.
The fast road cam will increase the contact pressure variations, and the metal gears will reduce the gear trains ability to deal with it. Put a good composite cam wheel back on!
Richard, when you fitted the fast road cam did you change the valve springs? If not then valve bounce might be an issue? Wouldnt appear at low revs though.
I'm not a fan of solid cam gears on these engines. Unlike the old Essex engine the composite gear teeth do not break up, unless there has been other mechanical damage in the engine. These cam drive gears are fairly simple angle cut rather than truely helical gears and they do not give the nice gradual engagement that a true helical gear would. Have a look at them. Being cut at an angle they also cause an end thrust which will magnify any end float in the cam itself. The reason Ford went to the trouble of using a composite gear is that the metal to metal ones cut this way are bloody noisy!
You know that, as you turn the engine over against the valves (plugs out) there is some variation in resistance as each valve spring is compressed or released. That causes differences in pressure on the cam, and differences in pressure on the cam wheel/cam drive wheel interface. The composite gear actually takes pressure variations on both sides of the tooth and pretty well deals with what would otherwise be chatter.
The fast road cam will increase the contact pressure variations, and the metal gears will reduce the gear trains ability to deal with it. Put a good composite cam wheel back on!
Valve springs are piper ones as per the cam kit.
I now have a good used wheel. I only changed it for solid as I dropped my origin and couldn't find a replacement. I didn't want to risk a weakened gear.
First stage is to fit the fibre one to the current setup, if the bottom gear allows it. See what happens. I'll probably make a flow chart!
I now have a good used wheel. I only changed it for solid as I dropped my origin and couldn't find a replacement. I didn't want to risk a weakened gear.
First stage is to fit the fibre one to the current setup, if the bottom gear allows it. See what happens. I'll probably make a flow chart!
Think that is the right approach. Worth putting in the effort to check the amount of end float you have on crank and cam, if either is excessive the gears are likely to chatter. Good luck, be very interested to hear what happens.
I once built a Ford V6 engine, very carefully. When I ran it there was a small but distinct tap at half engine speed, no choice but take it out again. Stripped it and didnt find a thing. Very p....d off indeed.
I had steam cleaned the block to check it. I went away a few days and left it in disgrace. When I came back I noticed a brown line deep down the bore. There was a crack in the block either from before, or caused by the rebore. It was just above the lowest point of the rings of one piston and was just opening at b.d.c..
You know how heavy those blocks are...it is now anchoring a boat mooring buoy!!
I once built a Ford V6 engine, very carefully. When I ran it there was a small but distinct tap at half engine speed, no choice but take it out again. Stripped it and didnt find a thing. Very p....d off indeed.
I had steam cleaned the block to check it. I went away a few days and left it in disgrace. When I came back I noticed a brown line deep down the bore. There was a crack in the block either from before, or caused by the rebore. It was just above the lowest point of the rings of one piston and was just opening at b.d.c..You know how heavy those blocks are...it is now anchoring a boat mooring buoy!!
Well, H.M.S. Morale hit a mine today, and is taking on water.
Sump has to come off
The crank gear is cut very slightly differently, and it's not suitable for the original fibre gear. My dreams of popping a fibre gear wheel back on and finding it sounding sweeter than the idea of Bianca Kajlich soaked in Golden Syrup are in tatters!
Now I'm either faced with the prospect of trying to find time to cut the lower beam out of the (freshly refurbished) chassis and modify it so it's a removable part, or I remove the engine. I don't really like the idea of cutting that brace out, but I like the idea of taking the engine out even less, and if I find a sensible way of doing the brace, I might be able to start incorporating the design into future chassis restos.
Bugger.
Sump has to come off
The crank gear is cut very slightly differently, and it's not suitable for the original fibre gear. My dreams of popping a fibre gear wheel back on and finding it sounding sweeter than the idea of Bianca Kajlich soaked in Golden Syrup are in tatters!
Now I'm either faced with the prospect of trying to find time to cut the lower beam out of the (freshly refurbished) chassis and modify it so it's a removable part, or I remove the engine. I don't really like the idea of cutting that brace out, but I like the idea of taking the engine out even less, and if I find a sensible way of doing the brace, I might be able to start incorporating the design into future chassis restos.
Bugger.
Bugger indeed! But only rats leave sinking ships 
so keep it afloat.
Not a great fan of the removable cross member, it simply cannot be replaced with a removable member which gives the same rigidity. But maybe I am just a cautious engineer.
?
Bit surprised to find the steel gear has a different tooth profile. I take it the two gears were changed together and from the same supplier?
But only rats leave sinking ships so keep it afloat. Not a great fan of the removable cross member, it simply cannot be replaced with a removable member which gives the same rigidity. But maybe I am just a cautious engineer.
?Bit surprised to find the steel gear has a different tooth profile. I take it the two gears were changed together and from the same supplier?
It was an alloy gear set. I didn't buy the steel one because (and you're going to love this).....I didn't want it to sound crap.
I know.
As for the removable member, I'm pretty much decided to do it, but I just want to figure out the best way to do it. Looking at the chassis, it can only really reinforce the distance between the lower chassis rails laterally, and possibly (at a stretch) spread the load transmitted by the engine mounts. The Cologne's a heavy old lump, so having that brace there sures things up a bit. I certainly wouldn't want to do without it. I just need to figure out a way of replacing it. I have a couple of ideas in my head, will sit on the can tonight and have a think
I know.
As for the removable member, I'm pretty much decided to do it, but I just want to figure out the best way to do it. Looking at the chassis, it can only really reinforce the distance between the lower chassis rails laterally, and possibly (at a stretch) spread the load transmitted by the engine mounts. The Cologne's a heavy old lump, so having that brace there sures things up a bit. I certainly wouldn't want to do without it. I just need to figure out a way of replacing it. I have a couple of ideas in my head, will sit on the can tonight and have a think
Don't be dismayed Richard....chassis member modification is apparently a doodle ...Tel did it in between cups of tea as far as I can tell....
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
...I couldn't, but I think you could
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
...I couldn't, but I think you could
AutoAndy said:
Don't be dismayed Richard....chassis member modification is apparently a doodle ...Tel did it in between cups of tea as far as I can tell....
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
...I couldn't, but I think you could
boltshttp://www.pistonheads.com/gassing/topic.asp?h=0&a...
...I couldn't, but I think you could
I'd be inclined to fit 2 of them and with larger - to retrieve some strength
It is the engineer in me I am afraid, always trying to analyse the stresses concerned and ensure a margin of safety! Not entirely sure TVR designed the chassis that way though! 
From an engineering design point of view Tel's mod is very slightly weaker in tension (which is probably the main stress), as strong in compression, but weaker in sheer and in torsion which increases stresses on the nearby chassis components.
If the holes for the bolts through the chassis are not sleeved then distortion of the main chassis rails is possible.
All theoretical of course, I haven't done any structural calcs...nor do I intend to try!. Like TVR, the viable approach is suck it and see I suppose. Tels is certainly better than at least one chassis mod I have seen.
One thing I would definitely do though. I would check carefully after it has bedded in and see if there is any sign at all of fretting.
Is this why all engineers seem to get early grey hair?
Not entirely sure TVR designed the chassis that way though! From an engineering design point of view Tel's mod is very slightly weaker in tension (which is probably the main stress), as strong in compression, but weaker in sheer and in torsion which increases stresses on the nearby chassis components.
If the holes for the bolts through the chassis are not sleeved then distortion of the main chassis rails is possible.
All theoretical of course, I haven't done any structural calcs...nor do I intend to try!. Like TVR, the viable approach is suck it and see I suppose. Tels is certainly better than at least one chassis mod I have seen.
One thing I would definitely do though. I would check carefully after it has bedded in and see if there is any sign at all of fretting.
Is this why all engineers seem to get early grey hair?
And I thought it was only there because, when making a chassis, it's easier to feed one length of tube through from outrigger to outrigger rather than two "stubs" terminating at the main chassis rails
Mine has been done a while now and no signs of any movement.
Edited by phillpot on Tuesday 5th July 07:58
phillpot said:
And I thought it was only there because, when making a chassis, it's easier to feed one length of tube through from outrigger to outrigger rather than two "stubs" terminating at the main chassis rails
It's much easier just welding some lengths of tube onto the side of the chassis rail, trust me! Trying to feed it through from one side to the other is actually harder to get right.Personally I think it's just to spread the load of the engine it's being thrown up and down over bumps etc.
FRom an engineering point of view, the solution TVRees has used has distinct advantages. The triangle of bolts is much more effective in handling sheer and torsion, the inherent strength of the tube through tube construction is maintained, and there are no bolts going through chassis tubes. The bigger the flange the better the stress is handled but what he has done looks a very good compromise and very well executed. As an engineer that wouldnt give me grey hair!!
From a structural POV, I also like TVRees' design.
I don't think it'll work for me though, as I still have my engine in, and won't be able to seam weld all the way around the circumference of the tube.
At the moment, I'm thinking more along the lines of Philpot's idea, only with a right angle on the bottom of each of the mounting plates to give them more strength. I might also install some bolts vertically into the chassis rail, as well as horizontally, all with crush tubes.
I'll continue to think. And cry.
I don't think it'll work for me though, as I still have my engine in, and won't be able to seam weld all the way around the circumference of the tube.
At the moment, I'm thinking more along the lines of Philpot's idea, only with a right angle on the bottom of each of the mounting plates to give them more strength. I might also install some bolts vertically into the chassis rail, as well as horizontally, all with crush tubes.
I'll continue to think. And cry.
Hi Richard
Sounds like you will have a nice car when done, On the Composite cam gear (fibre gear), I don't like them at all, I used to make my own gears (when I had the machines to do it), I always made Steel straight cut ones with a Vernier adjustment for accurate cam timing, I am sure these will be available from someone.
I do think Mike's idea is good if you have done all the painting but would go for a flange type fixing if it was a bare chassis.
Alan
Sounds like you will have a nice car when done, On the Composite cam gear (fibre gear), I don't like them at all, I used to make my own gears (when I had the machines to do it), I always made Steel straight cut ones with a Vernier adjustment for accurate cam timing, I am sure these will be available from someone.
I do think Mike's idea is good if you have done all the painting but would go for a flange type fixing if it was a bare chassis.
Alan
Gassing Station | S Series | Top of Page | What's New | My Stuff