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Discussion Starter · #1 ·
During the teardown I found this in the head area. Not sure what it is. Looks like some sort of thrust washer and a plastic circular or semicircular ring. The contour isn't the same as the bore size so a little confused. I will post a few more pics of the teardown as soon as my computer cooperates.

 

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owdskl said:
During the teardown I found this in the head area. Not sure what it is. Looks like some sort of thrust washer and a plastic circular or semicircular ring. The contour isn't the same as the bore size so a little confused. I will post a few more pics of the teardown as soon as my computer cooperates.

The plastic bit is the cam chain rubber that is on the cam (part number 2), second is the spacer/washer/shim (part number 5)that is used to on the end of the cam shaft to reduce end float, when replacing cam cover gaskets you should measure the gap between the cam end and the cover and use the correct shim to reduce the gap to factory spec (all in the maintenance manual)



Rod from OZ :cool:
 

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Discussion Starter · #3 ·
Heres some of the progress. I noticed that the left side piston had more carbon builup and there appears to be a gasket leak at the base of the cylinder as well. And damn that cam chain is going to be a pain in the ars to put back on. :cry:

 

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little bitty pics that you can't see
 

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Discussion Starter · #8 ·
Sorry about pic size. All of them were shot the same size. Not sure why one is bigger. You were right about the cam shaft plastic. I only had 1 thrust washer and the one chewed up one. The fiche shows a total of 4. One on each side of the cam shafts.
 

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owdskl said:
Sorry about pic size. All of them were shot the same size. Not sure why one is bigger. You were right about the cam shaft plastic. I only had 1 thrust washer and the one chewed up one. The fiche shows a total of 4. One on each side of the cam shafts.

What the fiche pictures in this case is irrelevant - most installations don't need any "thrust washers" at all.
Actually I think "shims" might be a better term to use here......

Dry fit the cam covers (bearings) with gaskets, then measure the end play of the cam.
If it's out of spec (0.002"-0.014") and needs shims, try to use one on each side, if possible.
If it's "under" spec (too tight), try using an extra gasket on one side.
 

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tbpmusic said:
owdskl said:
Sorry about pic size. All of them were shot the same size. Not sure why one is bigger. You were right about the cam shaft plastic. I only had 1 thrust washer and the one chewed up one. The fiche shows a total of 4. One on each side of the cam shafts.

What the fiche pictures in this case is irrelevant - most installations don't need any "thrust washers" at all.
Actually I think "shims" might be a better term to use here......

Dry fit the cam covers (bearings) with gaskets, then measure the end play of the cam.
If it's out of spec (0.002"-0.014") and needs shims, try to use one on each side, if possible.
If it's "under" spec (too tight), try using an extra gasket on one side.
I have found that the "honda" gaskets are thicker than the aftermarket gaskets and tend to be fairly close to required spects.
But "and there is always a but" an engine that requires a rebuild will need some checking in this area as the shims do wear the alloy housing requiring either a thinner gasket or thicker shims to close the gap. The shims do appear on Evilbay from time to time and are available in 0.1 and 0.2mm. I have some 0.3mm ones that came with some extra gear i brought years ago but have not seen a honda number for them :roll:

Rod from OZ :cool:
 

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I forgot to address your running problem - air leak is a good possibility, considering your comments.

But be advised that tight intake valves will also cause runaway idle on 450's.
This has been corroborated by Terry Naughton of Team Hansen, who's observed it as well. If there's anyone who humbles me with his 450 juju, it's Terry.

The "book" setting of 0.0012" is ridiculous - normal humans can't really do that with any repeatability, and the feelers are like tinfoil. 0.0015" isn't much better. It's very easy to get it too tight......
Most of us use 0.002", I've done it for over 40 years - Terry uses 0.005" on his racers.
 

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tbpmusic said:
owdskl said:
Sorry about pic size. All of them were shot the same size. Not sure why one is bigger. You were right about the cam shaft plastic. I only had 1 thrust washer and the one chewed up one. The fiche shows a total of 4. One on each side of the cam shafts.

What the fiche pictures in this case is irrelevant - most installations don't need any "thrust washers" at all.
Actually I think "shims" might be a better term to use here......

Dry fit the cam covers (bearings) with gaskets, then measure the end play of the cam.
If it's out of spec (0.002"-0.014") and needs shims, try to use one on each side, if possible.
If it's "under" spec (too tight), try using an extra gasket on one side.
I have no idea what you guys are talking about ! I can't find this in the Honda manual. Maybe I'll understand when I get there but, do you have the page/section number in the Honda shop manual where this is defined ?
 

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RicH2 said:
I have no idea what you guys are talking about ! I can't find this in the Honda manual. Maybe I'll understand when I get there but, do you have the page/section number in the Honda shop manual where this is defined ?




The arrow in the photo indicates where the shim actually goes (if you need it). Right between the end of the cam cover and the shoulder of the cam.
The manual page is from the Annotated 450 Manual......
 
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