I was changing the valve cover gasket today and decided to check the bearing cap bolts (just because they were there, or maybe it was just instinct, good thing I did too!) and for the intake cam, for the far right bearing cap (furthest from the cam gears) the bolts were loose, as in I could wiggle them. :eek I tried to GENTLY move the bearing cap itself but it didn't move.

So, I checked the other bearing cap bolts. I could not move or turn any other bolts by hand, but the rest of the intake cam bearing cap bolts were under-torqued. The torque spec is listed as 8.9 ft*lbs, and they needed a little tightening to get there; best guess is that they were at about 6 ft*lbs or so.

Note that the exhaust cam bearing cap bolts were all fine and at the proper torque, as were the bolts for the large bearing cap right next to the cam gears. I did not take off the bearing caps to inspect them (I guess I should have), and I did not notice anything unusual with them, such as unusual metal shavingsm or wear, and the car has seemingly run just fine.


SO, the question is: Did I do any undue damage to my cam shafts, cylinder hear, or bearing caps? My guess is no, as everything seems to be fine, but I'd like a second opinion on this.

As to HOW this happened, well maybe they (if this is even posible) got loose from heat cycling (but why only the intake side?), maybe the more agressive cams (crower stage 2) and stiffer titanium springs did this (again, why only intake), but it may be that when I torqued them both down, I missed the last step on the intake when doing it (It seems unlikely to me, asI am typically very thorough with these things, but certainly possible) and only got to 6 ft*lbs and didn't do the last 9 ft*lbs step.

And idea as to what it could have been, besides the stupidity of the owner (it's almost ALWAYS the nut behind the wheel's fault)

thanks everyone

Im leaning to the cam and spring setup. How long have you been running on them? Remember that the engine and timing belt only move in one direction. Maybe somehow this was enough to reach the right frequency.

Most engineers will tell you... torque settings are to make sure parts do not vibrate loose from hitting certain frequencies.

Same thing happened to a motor my friend and myself built for his integra. We are thinking something along the lines of the timing belt was too tight closest to the caps that were working their way loose. Could have been anything really, but just re torqued them with some loc-tight and they haven't come loose since.

I checked when I put the cam in the car which would have been the last time I did anything with the cylinder head - it was a little longer than I realized, 3 years ago.

So it was potentially like this for three years? Three years of racing, driving, sitting in the freezing cold, etc.. Maybe I just got to it in enoug time, maaybe it would have been fine, who knows? :shrug

I doubt you did any damage. I wouldn't worry about it.

Didn't think so Dino, but glad to hear from you and everyone that I should be ok. Or at least the car is ok, I still don't know about myself