Valve Cover Bolts Torque Spec

[NacsMXer]

Hey guys, just got finished installing a new Hotcam in my motor. Every time i've installed cams in the past i've always used a small 1/4" drive ratchet and tightened the small 8mm head cover bolts by feel. While that works, it doesn't guarantee that you are torquing them all evenly. There is also sort of a gray area on the official spec in the factory service manual.

This time I used my inch-pounds torque wrench and used the spec Hotcams provides.
86 inch/lbs or 7.2 ft/lbs works perfect and they are all torqued evenly now!

Just passing this along for anyone needing this info in the future :)

[CarGuy7a]

When I did mine a while back I just guessed at it and torqued mine at 90 inch/lbs. I guess I was pretty darn close then.

[supraloud84]

After snapping a couple of those bolts in a few of the ex's. One of my buddies starting digging a little bit. Come to find out that for that size of bolt the recommended torque spec is nearly half of what honda calls for in the manual. i dont recall the exact spec. My buddy that found this info is a member on here so maybe he will chime in the the numbers.

[CJM]

Looking right at the manual atm and it says cyl head cover bolt (which I assume is the valve cover bolt) 17 ft-lbs. I somehow read it wrong and torqued mine and a buddys to 33 ft-lbs which is the spec for the cyl head nut.

I wonder if it will cause any issues..

[CarGuy7a]

Well there is one big bolt for the valve cover. That is the one that gets torqued to 17 ft/lbs I believe.

The ones NacsMxer is referring to is the small perimeter bolts.

I assumed the torque spec for the big bolt was also for the perimeter bolts. I tried to tighten the small perimeter bolts to that high torque and one started feeling weird (almost at the point of stripping) so I immediately stopped. My father looked at it and said hmm that torque is way too high for that small of a bolt. So he said just torque the small ones to about 88 or 90 inch/lbs and the big bolt to what the book says.

[JOHNDOE83]

When I put my cam in I tryd to torque the bolts to spec..

they almost striped and broke....I threw out the torque specs and tightend them down in a cris cross pattern.....never had a leak....never broke or stripped a bolt.

The factory has machines that do it in a speacial way, most of the time honda mechanics dont even use the toque specs.

[NacsMXer]

Originally posted by CJM
Looking right at the manual atm and it says cyl head cover bolt (which I assume is the valve cover bolt) 17 ft-lbs. I somehow read it wrong and torqued mine and a buddys to 33 ft-lbs which is the spec for the cyl head nut.

I wonder if it will cause any issues..

33 ft lbs is way too much for that one. Go back to 17 ft lbs if it's a stock cam or 10 ft lbs if it has a Hotcam in it. It's the center "12 mm head" bolt like CarGuy7a said. That bolt is closest to the cam, and the headcover supports the cam journals. So if you have too much torque on it, you are putting too much pressure on the cam journals/bearings.

This torque spec confuses a lot of people including myself at one time because it says "8mm" head cover bolt. I'm sure CarGuy7a and JOHNDOE83 made the same mistake lol. It has a 8mm thread/shaft but a 12mm head on it, so a lot of people think that it is for the smaller 8mm head/6mm thread bolts that secure the valve cover. I snapped one of those little bolts in half the first time I did a cam swap trying to torque it to 17 ft lbs. Go with the 86 inch/lbs or 7.2 ft/lbs for the smaller "8mm head" valve cover bolts, it works perfect i'm telling ya! You want nice even torque clamping that camshaft in place ;)

[CJM]

Well I did do it in a criss cross pattern at least. Ill have to take it all apart and do it again.

[NacsMXer]

Originally posted by CJM
Well I did do it in a criss cross pattern at least. Ill have to take it all apart and do it again.

I usually torque that one fully last anyway (tighten it half on the 1st criss cross pass, fully on the next), so not sure if you would have to undo all the smaller bolts just to retighten that one bolt. I would just carefully back it off a little bit and retorque to 17 ft lbs (10 if it has a Hotcam) :macho

[CJM]

Just redid them all, 7.5 for the 8mm and 10 for the middle one thats 12mm actually.

Ya know I had no issues torquing them to 33 last time either. Also redid the valves to be sure since the clamping force is different now with less pressure on them.

Funny tho, redid it all and I didnt remove the gas tank but just slid it off a bit and i go for a ride and it sputters then shuts off.

Ok I figure its outta gas , push it back and check everything, add gas. Hmm, wont start period..odd. Figure wtf did I break now. Then I look at the fuel line from the tank, got twisted lol..

[NacsMXer]

Originally posted by CJM
Just redid them all, 7.5 for the 8mm and 10 for the middle one thats 12mm actually.

Ya know I had no issues torquing them to 33 last time either. Also redid the valves to be sure since the clamping force is different now with less pressure on them.

Funny tho, redid it all and I didnt remove the gas tank but just slid it off a bit and i go for a ride and it sputters then shuts off.

Ok I figure its outta gas , push it back and check everything, add gas. Hmm, wont start period..odd. Figure wtf did I break now. Then I look at the fuel line from the tank, got twisted lol..

Lol, that's frustrating when that happens but I love when it's something stupid like that :p

I bet your cam will be much happier without so much pressure on it now haha. That was smart of you to redo the valves because there is a difference now. And you're right it's a 12mm head for that center bolt, I edited my post so I don't throw someone off.

[CJM]

Yea everything worked out good, seems so odd to torque those 8mm head (actually a 6mm shaft) valve cover bolts to less than 10 ft-lbs since it barely requires effort. Had been thinking about doing them to 10-12 ft-lbs b/c it just seemed so little.

Im sure everything is fine tho :)

[NacsMXer]

Originally posted by CJM
Yea everything worked out good, seems so odd to torque those 8mm head (actually a 6mm shaft) valve cover bolts to less than 10 ft-lbs since it barely requires effort. Had been thinking about doing them to 10-12 ft-lbs b/c it just seemed so little.

Im sure everything is fine tho :)

Yeah I think in the factory manual, there is a torque chart for the 8mm head bolts. It's not specifically for the valve cover bolts, but for any bolt of that size on the machine (i.e. oil filter cover bolts, valve cover bolts, cam chain tensioner bolts, etc). It's listed at 9 ft lbs. So 10-12 would be a little over and that's not good for those tiny bolts. Being that I and a lot of people use oil/antiseize on the threads of the bolts, it's better to go a little less and use the 86 inch/lbs or 7.2 ft lbs. 9 ft lbs would be more accurate if the motor was new and the threads were clean and dry but that ain't reality in 98% of the motors out there.

I tell you what though, it's much nicer to get those tiny bolts with a torque wrench and have them all even than to do it by feel. That part always made me nervous because they strip/break easy and you can never tell if you have them exactly even doing them by hand.

[CJM]

Friend of mines was totally overtoqued, the bolts were almost all helicoiled and they wouldnt tighten anymore, one was even tapped for a standard thread pitch with an allen head. We had to tap them all out for 7mm thread with 10mm head instead. We did 12ft-lbs and its been holding fine

Honestly if anything my torque wrench is probably not that accurate, its old and beatup and lowest it goes (its a 3/8 old, old, old craftsman that no longer locks in the adjustment too) is 10 ftlbs. Im sure its fine. I am amazed that it held 33ft-lbs with no issues before honestly.

Im not worried until it starts to leak..