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Discussion Starter · #1 ·
Trying to remove the head in my '76 framed T140 with a '71 motor, here's the problem:
There are 4 torque stay bolts on the rocker box covers and when I tried to remove the 4 bolts hit the bottom of the frame (where the gas tank mounts)

What should I do to get these out so I can remove the rocker covers then the head? Are there supposed to be 4 torque stay bolts?
Thanks in advance for the help!

This just doesn't seem right even according to the manual.
 

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You should always remove the rocker boxes before the head, I don't think you can get the head off with them there. Do you have a shop manual? If not, it would sure help a lot.
 

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Discussion Starter · #4 ·
68TR6R, that's the problem, I can't even take the rocker boxes off because the 2 torque bolts are too long to clear the frame on each of the rocker boxes.

I guess I will have to loosen the motor mounts like GrandPaulZ suggested to get them out. Yes, I have 3 different shop manuals for this bike.

My next question is: because this motor is 5 years older than the frame is this why I am having a clearance issue or are the bolts the problem?
Thanks again!
 

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OK. I see what you're saying now. Me, I'd hack off enough of the bolt to get them out and buy the correct sized ones for re-assembly
 

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Discussion Starter · #8 ·
Yup, I think it's much easier to hack them off at this point like you said. It's amazing how many things I've noticed that are assembled wrong or done incorrectly on this bike but for what I paid for it I'm not going to complain! :)
She may look nicebut the beauty is oly skin deep! :)
 

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It looks like you have the head bolts (and maybe rocker boxes) form a 70 or earlier top end. The oil in frame (71 and later) had shorter head bolts that fit inside the rocker boxes. The new style rocker boxes had to be redesigned by removing material to clear the head bolt head that is now inside so it is not as strong in compression (like when you torque the head bolts) as the old style box. The new style rocker box bolts threaded into the top of the new head bolts. The factory had to go to that set up for exactly the reason you are experiencing, i.e. "ya cant get the old style head bolts past the top frame". Only way around it is as GPZ says, tilt the whole engine. Kinda a PIA ain't it.
I see others have suggested "Hacking off the bolts" while I was compsoing this. If you do that and have the old style rocker boxes, the new correct bolts aren't going to fit inside so you'll have to get the correct boxes also. Easy check for correct boxes is if they have two rolled dowels to locate the boxes.
 

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Discussion Starter · #10 ·
Jimmy,
Thanks for all the info. That makes a lot of sense now!
Maybe that's why the part# book I have doesn't match up to what I have for a '71 motor. I would like to get the correct rocker boxes and bolts so I don't have to go through this again.

Oh yeah, the reason I have to take the heads off in the first place is because I took out the left side spark plug and low and behold a heli-coil came out with it too. :mad:

Thanks again for all of the info. everybody.
 

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yeah, I'd get the correct rocker boxes too. There's no sense dealing with that everytime and I imagine the correct ones can be found relatively easily
 

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leave the head on and install a new helicoil or better yet a timesert .
 

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Discussion Starter · #13 ·
After looking at my "Triumph Replacement Parts Catalogue"
engine section (which gives a detailed view) it looks like I might need a new head in order for the correct rocker boxes to work.
There is a slightly different configuration of the bolt pattern for the "Cylinder head bolts (for torque stay)".
 

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The configuration changed but the pattern is the same. There were some pattern changes when Triumph went from 8 head bolts to 9 and later 10 but any 9 bolt can be used on any 9 bolt cylinder. The rocker boxes can be interchanged also to accomodate the different head bolt configuration. On earlier engines, the head bolt clamping pressure is applied on the top of the rocker boxes on the two inner head bolts and the rocker boxes were designed to accept this clamping force. The head bolt holes that passed through the earlier boxes fit fairly snug around the shank of the head bolts so were held in alignment by them. On later engines, the head bolt clamping pressure is applied directly to the top of the head. The later boxes are not as strong in compression because they had material removed from the bolt area to clear the bigger size of the head bolt head which is now inside the rocker box. The later boxers had 2 small roll pins that located the rocker boxes correctly to the head for proper gasket surface match.
 
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