Author Topic: Super tight cam cap bolts  (Read 1721 times)

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Offline Chuck Hahn

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Super tight cam cap bolts
« on: March 28, 2018, 07:50:09 PM »
So Ive been working on this 79 CB 750K on and off and finally got a new cam cover gasket in and was gonna check valves.   SADLY, I saw that one of the shim buckets has a small chip out of the rim the shim sets into.  No biggy, take the cam out and replace the offending bucket right??  So i tried to loosen a bolt and it seemed incredibly uncredibly tight,  so for fear of snapping a bolt off i stepped away.

Question is did they get loctited at the factory??  I was thinking get the MAPP gas out and heat the heads of the bolts so heat will migrate down and possibly loosen any thread locker???   How should i tackle this so I dont snap any bolts off in the head while trying to swap out that damaged bucket???

Offline Chuck Hahn

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Re: Super tight cam cap bolts
« Reply #1 on: March 29, 2018, 07:23:25 PM »
Noone??   Any tips at all???

Offline HondaMan

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Re: Super tight cam cap bolts
« Reply #2 on: March 29, 2018, 08:33:44 PM »
Could be the DOHC bias here?;)
If the chip is not big enough to let the shim lift up, I wouldn't worry about it. It's not going anywhere.
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Offline MikeSimon

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Re: Super tight cam cap bolts
« Reply #3 on: March 30, 2018, 05:02:42 AM »
On a DOHC, you do not have to remove the cam(s) to take a shim out. You need the proper tool(s) for valve adjustment, rotate the engine/cams to the proper position, depress the valve and fish the shim out.
Be careful applying raw force to the cam cap bolts. They have a tendency to snap. Even when taking them out.
1973 CB350F -sold
1974 CB350F -218 orig miles, sold
1976 CB750K - in restoration

Other Hondas:
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CB1100R
GB500
Plus Kawasakis, BMws & Ducatis

Offline MikeSimon

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Re: Super tight cam cap bolts
« Reply #4 on: April 02, 2018, 04:24:40 PM »
Noone??   Any tips at all???

So, you are complaining you don't get an answer and when you finally do, you are one of these guys who don't bother to say anything. That's probably why people don't take the time to respond.... ::)
1973 CB350F -sold
1974 CB350F -218 orig miles, sold
1976 CB750K - in restoration

Other Hondas:
3 x CBX
CB1100R
GB500
Plus Kawasakis, BMws & Ducatis

Offline Chuck Hahn

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Re: Super tight cam cap bolts
« Reply #5 on: April 06, 2018, 06:30:03 PM »
Well  Mike. seeing i have been really busy and not checked back to the thread till just now !!!!   Im gonna read and catch up on all the responses.

Offline Chuck Hahn

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Re: Super tight cam cap bolts
« Reply #6 on: April 06, 2018, 06:32:31 PM »
And yes I know you need the bucket compressing tool and I got the Motion Pro one here now.   Same kinda set up as all me Suzuki GS bikes use..shim over bucket.

Offline Chuck Hahn

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Re: Super tight cam cap bolts
« Reply #7 on: April 06, 2018, 06:34:54 PM »
Hondaman.  The chip was maybe 3/16 inch of the rim.  Got one off Ebay and just installed that and set the cam back in place.   Now I gotta get new bolts as AMC had PMed me advising the stock ones have a legacy of snapping.

Offline MikeSimon

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Re: Super tight cam cap bolts
« Reply #8 on: April 07, 2018, 02:10:33 PM »
So, why did you take the cam out??
1973 CB350F -sold
1974 CB350F -218 orig miles, sold
1976 CB750K - in restoration

Other Hondas:
3 x CBX
CB1100R
GB500
Plus Kawasakis, BMws & Ducatis

Offline Chuck Hahn

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Re: Super tight cam cap bolts
« Reply #9 on: April 09, 2018, 07:13:09 PM »
To replace the shim bucket that had the broke off piece of the rim the shim seats in.   Got a bucket off Ebay for it.  Im so overwhelmed and hope i can get back to the bike soon...but not to optomistic at this very minute.......chase that all mighty dollar when ya get a chance....LOL

Offline MikeSimon

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Re: Super tight cam cap bolts
« Reply #10 on: April 10, 2018, 09:01:31 AM »
Make sure you got the right bucket. The DOHC buckets are coded for the "holes". At least two different ones, "A" and "B"
1973 CB350F -sold
1974 CB350F -218 orig miles, sold
1976 CB750K - in restoration

Other Hondas:
3 x CBX
CB1100R
GB500
Plus Kawasakis, BMws & Ducatis