Author Topic: Rubber Pucks / Solid Aluminum Instead ?  (Read 1675 times)

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Offline george

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Rubber Pucks / Solid Aluminum Instead ?
« on: June 14, 2012, 10:04:30 AM »
  Is there any sure fire way to keep these from leaking ? Bike is K2, Old Ned's on the forum here. I have been helping him rebuild this top end and have become gun shy about these pucks under the cam towers. When I did the top end on my K8 I thought I followed HondaMans directions carefully but I'm leaking. It seems to be coming from around 2-3 spark plug areas. I did not re-torque my head bolts.
  So to avoid this on Ned's motor, any input? Has anyone ever heard of or tried using solid aluminum plugs in place of the rubber pucks? How about using a quarter and some pooky.
  Thanks gents, couldn't find any info on this with the search feature.
Found this bike in completely stock condition in Feb. 08. Paid over twice what my new one cost 30 years ago. Am trying to re-create the look of the late 70's Drag Bike styling.More later. 4-2-10 It ain't stock any more and I have no idea what I am trying to create !

Offline MCRider

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Re: Rubber Pucks / Solid Aluminum Instead ?
« Reply #1 on: June 14, 2012, 10:38:10 AM »
  Is there any sure fire way to keep these from leaking ? Bike is K2, Old Ned's on the forum here. I have been helping him rebuild this top end and have become gun shy about these pucks under the cam towers. When I did the top end on my K8 I thought I followed HondaMans directions carefully but I'm leaking. It seems to be coming from around 2-3 spark plug areas. I did not re-torque my head bolts.
  So to avoid this on Ned's motor, any input? Has anyone ever heard of or tried using solid aluminum plugs in place of the rubber pucks? How about using a quarter and some pooky.
  Thanks gents, couldn't find any info on this with the search feature.
If you think about it retorquing the head nuts has nothing to do with the pucks. Two different levels. If anyhting you would retighten the cam tower bolts (2) and the bearing cap hold downs (4). But be real careful as these shouldn't require much and are prone to stripping.

I thnk you'll find that HMs procedures are your best bet.

On yours, had you removed the 4 studs holding down the cam towers?  When those leak they mimic a leak in the rubber puckies.
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Offline george

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Re: Rubber Pucks / Solid Aluminum Instead ?
« Reply #2 on: June 14, 2012, 07:19:46 PM »
  Is there any sure fire way to keep these from leaking ? Bike is K2, Old Ned's on the forum here. I have been helping him rebuild this top end and have become gun shy about these pucks under the cam towers. When I did the top end on my K8 I thought I followed HondaMans directions carefully but I'm leaking. It seems to be coming from around 2-3 spark plug areas. I did not re-torque my head bolts.
  So to avoid this on Ned's motor, any input? Has anyone ever heard of or tried using solid aluminum plugs in place of the rubber pucks? How about using a quarter and some pooky.
  Thanks gents, couldn't find any info on this with the search feature.
If you think about it retorquing the head nuts has nothing to do with the pucks. Two different levels. If anyhting you would retighten the cam tower bolts (2) and the bearing cap hold downs (4). But be real careful as these shouldn't require much and are prone to stripping.

I thnk you'll find that HMs procedures are your best bet.

On yours, had you removed the 4 studs holding down the cam towers?  When those leak they mimic a leak in the rubber puckies.
Thanks MC , No , did not remove those studs. I changed the head gasket because it actually blew out on #3, I mean to the point of shooting fire out. I did nothing more than clean up the mating surfaces , and put on a new gasket, I missed something .I think maybe my desire to ride made me careless somewhere ! So now , in riding season , it comes back apart ! Sad !
Found this bike in completely stock condition in Feb. 08. Paid over twice what my new one cost 30 years ago. Am trying to re-create the look of the late 70's Drag Bike styling.More later. 4-2-10 It ain't stock any more and I have no idea what I am trying to create !

Offline Don R

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Re: Rubber Pucks / Solid Aluminum Instead ?
« Reply #3 on: June 14, 2012, 09:28:09 PM »
They were rubber nickels, now a quarter fits in there. Inflation I guess.
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Offline george

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Re: Rubber Pucks / Solid Aluminum Instead ?
« Reply #4 on: June 14, 2012, 09:35:03 PM »
They were rubber nickels, now a quarter fits in there. Inflation I guess.
Yes sir , nickel wont work anymore , quarter fit pretty well actually !
Found this bike in completely stock condition in Feb. 08. Paid over twice what my new one cost 30 years ago. Am trying to re-create the look of the late 70's Drag Bike styling.More later. 4-2-10 It ain't stock any more and I have no idea what I am trying to create !

Offline chewbacca5000

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Re: Rubber Pucks / Solid Aluminum Instead ?
« Reply #5 on: June 15, 2012, 04:56:23 AM »
In order to avoid future leaks under the pucks sealant is required.  Can't remember which one though.  The puck shrink over time and leak.

Also the leak between 2 and 3 cylinders is probably caused by head warp.  I had a leak in the same place and the head was not flat.  I would check it with a straight edge and if not perfectly flat it will need a press or be milled flat.  Resembling with heavy duty studs really helps too.

As for the aluminum disk they won't shrink, but I am not sure they would make a seal either.

Offline 70CB750

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Re: Rubber Pucks / Solid Aluminum Instead ?
« Reply #6 on: June 15, 2012, 06:19:46 AM »
I think he means something like engine block plugs.  But if Honda believed they would they would use them.
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