well, I think I may have run into an engine that's been serviced by someone who used an impact wrench to reassemble things.
I got the left head off without too much difficulty, but noticed that the 6mm bolts that hold down the cam bearings were too tight. They required a pretty good tug to break them loose, and a loud "crack" with each one breaking loose. And pulling the top bearing plate off was way tighter than I remember on my own bike. The head bolts took way more than their spec 42 ft-lbs to break loose, but I got them out without incident.
But the real fun was on the right side. Bearings were similar to the left, but 2 of the 6 head bolts just would not break loose. The 4 that did break loose were probably at least 75 ft-lbs before they released (15" Snap-On 1/2" drive ratchet with all my strength). Edit: I've used this ratchet for years to loosen lug nuts on my truck that are 125 ft-lb and it was less effort than with these bolts, so I think the 75 ft-lb figure is probably way low, they were crazy tight.
So, the right head is going to stay put for now, I used a 6pt SnapOn socket and its a bit buggered now, and I think the bolt head is too, I can't seem to get a really good drive on it now.
Any chance at all that these were factory torqued bolts and they just got this stubborn over 27 years on the bike? Or did someone likely put it back together with an impact?
I got the left head off without too much difficulty, but noticed that the 6mm bolts that hold down the cam bearings were too tight. They required a pretty good tug to break them loose, and a loud "crack" with each one breaking loose. And pulling the top bearing plate off was way tighter than I remember on my own bike. The head bolts took way more than their spec 42 ft-lbs to break loose, but I got them out without incident.
But the real fun was on the right side. Bearings were similar to the left, but 2 of the 6 head bolts just would not break loose. The 4 that did break loose were probably at least 75 ft-lbs before they released (15" Snap-On 1/2" drive ratchet with all my strength). Edit: I've used this ratchet for years to loosen lug nuts on my truck that are 125 ft-lb and it was less effort than with these bolts, so I think the 75 ft-lb figure is probably way low, they were crazy tight.
So, the right head is going to stay put for now, I used a 6pt SnapOn socket and its a bit buggered now, and I think the bolt head is too, I can't seem to get a really good drive on it now.
Any chance at all that these were factory torqued bolts and they just got this stubborn over 27 years on the bike? Or did someone likely put it back together with an impact?
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