Cam Sprocket Problems

mustang6771 · Posted: Mon Mar 08, 2010 2:46 pm Post subject: Cam Sprocket Problems

So I posted here a week or so ago about breaking something in my engine that I assumed was my cam chain. I finally got to breaking it all down and found that the chain is fine.
What I found was the two bolt heads from the cam sprocket lying in the cam case with the other half of each (the threaded half) screwed into the cam sprocket. One of the threaded halfs was screwed in completely like it should (only missing the head) while the other was halfway screwed in. I believe that one of the bolts vibrated free enough for the sheer forces to break it leaving only one bolt for the work of two and that ended up breaking due to increased stress.
Here's what I'm going to do and this is where I want some opinions if I'm heading in the right direction:
I'm going to replace the cam tensioner wheels, check for any damage that may have happened but I think I'm good, replace the cam bolts and use locktite this time. I think I may replace the cam chain but I'm not sure if that's something I need to do.

I'm running a 70's ish cam in my K0 model but I've been running that for a while so I don't believe that that is the cause of all this.

Bikegeezer · Posted: Mon Mar 08, 2010 6:35 pm Post subject:

One of those bolts is threaded all the way, and the other isn't. They need to go in the specific locations shown in the service manual - not interchangeable. They're special hardened bolts and get tightened to 10 - 13 ft, lbs, if I remember correctly. Use a torque wrench and blue Loctite.

Stu

tbpmusic · Posted: Mon Mar 08, 2010 9:13 pm Post subject:

Correct, Stu - the shouldered bolt goes in the top hole when installing.

Those are special bolts, and haven't been available in many years.
Good luck finding any........

mustang6771 · Posted: Tue Mar 09, 2010 9:20 am Post subject:

I have an extra set of bolts so I'm not worried. I've picked up a few complete cam sets on ebay for $20 over the past few months. I guess I wanted to know if anybody thought that my analysis of the problem is correct. If Stu says I need locktite on the screws then, guess what? I'm definately putting locktite on them screws.

Also, one of the spare cams I have is missing the little nipple that the advancer aligns to. If fell out when I was working on the engine a few months ago. It was there when I started and wasn't there when I went to go put it back in. I tried to remove one from another cam but couldn't. I think it's press fit in there pretty good. I found this odd.

tbpmusic · Posted: Tue Mar 09, 2010 9:36 am Post subject:

mustang6771 · Posted: Wed Mar 10, 2010 1:27 pm Post subject:

What other bolts/screws are known to have fallen out so that i can use locktite on them? I wanna make sure this is the last time I need to go through this for a while.

fasterspider · Posted: Wed Mar 10, 2010 1:57 pm Post subject:

I only used Lock-Tite thread locker on my cam sprocket and countershaft sprocket bolts in my 350 engine.

I learned the hard way about Lock-Tite on cam sprocket bolts when one backed out of the cam and fell down and broke my cam chain leaving me stranded 25 miles up into the San Gabriel mountians.

fasthonda · Posted: Thu Mar 11, 2010 6:49 pm Post subject: Cam Bolts

Sounds like wrong bolts were used as this has never happend to me in 50 years locktite will always help. most honda motors will not break bolts if factory parts are used where they should be used as engineered by Honda.Good Luck Fast Honda Cool