Looks like I'll be getting one of those race caps with bellows, makes sense. As for the vibrations, thanks for the guidance guys. I will get it up on axle stands and have a play this weekend. It is quite serious vibrations. Maybe there is something wrong with one of the engine mounts, as to unscrew the cam cover in a few hundred miles and to shake me almost senseless must be something like that.
Might need your support Andrew R if you have any time?
I will be tied up with kids stuff on Saturday but I may have some time on Sunday. Better check plans with the social secretary. I don't mind offering support but I think you will find the axle stands work better!
This may be a silly question from someone who drives and not built !, are the engine mounts straight or angled, if they are angled and fitted the wrong way round is the engine set back further than should be ?.
Can't see it myself. One mount has a triangular base and a significant angle in the horizontal, the other mount angles vertically. Incorrect fitment of either would stop the other fitting at all and try to put the engine all over the place, wrong height, canted over etc.
I guess it could happen if there was too much tolerance around the various bolts holding the mounts to the engine and the chassis but, from memory of my build, they were all a pretty good fit.
Good point about the steering column.
Wiggle all the exhaust joints and brackets? Loosen them one at a time and see if it affects the vibration?
Ditto engine and gearbox mounts?
Take up thy stethoscope?
It's probably worth jacking up the engine a bit either before or immediately after getting the car on stands and seeing if that changes anything.
I had a similar vibration which gave an unpleasant fuzzy feeling which made me feel quite sick. Traced the problem to a primary pipe touching the chassis (incorrectly made). This was on a new Sigma.
I have diagnosed the problem. I checked Primaries, steering, engine mounts and gearbox. All is perfect apart from teh gearbox.
Basically its sitting on the left hand side (near side) on the chassis. It's mounted centrally, I don't see how I could move it further right. The only immediate option is to push the tail end of the gearbox higher with some form of spacers under the chassis mount.
I took some photos, and the best ones are here. I'd really like your thoughts, as this is the current most common gearbox so surely others may be experiencing the same problem. If they haven't owned a Caterham previously they may even think that "they all do that".
Looks like I'll be getting one of those race caps with bellows, makes sense. As for the vibrations, thanks for the guidance guys. I will get it up on axle stands and have a play this weekend. It is quite serious vibrations. Maybe there is something wrong with one of the engine mounts, as to unscrew the cam cover in a few hundred miles and to shake me almost senseless must be something like that.
Might need your support Andrew R if you have any time?
SV VVC 170 - 170.4 bhp @ 7100 rpm - 142.4 ft.lb. @ 4900 rpm
This may be a silly question from someone who drives and not built !, are the engine mounts straight or angled, if they are angled and fitted the wrong way round is the engine set back further than should be ?.
John.
You couldn't really do that JNC, all sorts of things wouldn't line up, gearbox mount, exhaust, inlet......
....and I'm sure it would be picked up at the PBC. Well I would hope so!
If you are only talking mm it's possible!
John.
Can't see it myself. One mount has a triangular base and a significant angle in the horizontal, the other mount angles vertically. Incorrect fitment of either would stop the other fitting at all and try to put the engine all over the place, wrong height, canted over etc.
I guess it could happen if there was too much tolerance around the various bolts holding the mounts to the engine and the chassis but, from memory of my build, they were all a pretty good fit.
Good point about the steering column.
Wiggle all the exhaust joints and brackets? Loosen them one at a time and see if it affects the vibration?
Ditto engine and gearbox mounts?
Take up thy stethoscope?
It's probably worth jacking up the engine a bit either before or immediately after getting the car on stands and seeing if that changes anything.
Jonathan
John Vine published a list of factors but the links are broken.
Broken link now fixed.
JV
I have diagnosed the problem. I checked Primaries, steering, engine mounts and gearbox. All is perfect apart from teh gearbox.
Basically its sitting on the left hand side (near side) on the chassis. It's mounted centrally, I don't see how I could move it further right. The only immediate option is to push the tail end of the gearbox higher with some form of spacers under the chassis mount.
I took some photos, and the best ones are here. I'd really like your thoughts, as this is the current most common gearbox so surely others may be experiencing the same problem. If they haven't owned a Caterham previously they may even think that "they all do that".