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grahambehan
11-05-2019, 03:28 PM
Found on a recent teardown

Graham
billschroeder5842
11-05-2019, 08:16 PM
Yikes- that is scary!
XfireZ51
11-05-2019, 08:35 PM
Graham,

Any sense on the cause of failure? Are these OEM?
grahambehan
11-06-2019, 08:48 AM
Graham,

Any sense on the cause of failure? Are these OEM?

Valve guides are stock. From the uneven tool marks on the end of the guides, they were over stressed whilst being knocked back to perform the port work then knocked back into position. After that it was just a matter of time.

Graham
XfireZ51
11-06-2019, 09:31 AM
Thx Graham. Any outward signs, ie oil burning, spark plug coloring, indicative of a problem here?
grahambehan
11-06-2019, 09:42 AM
Thx Graham. Any outward signs, ie oil burning, spark plug coloring, indicative of a problem here?

No comments from the owner re that, although it has heavy carbon deposits. The actual reason for taking it apart was, no compression on cyl 7 due to the parts of valve guide passing through the cylinder.

Graham
Jagdpanzer
11-06-2019, 05:38 PM
Graham,
Do you have any experience with the VG 19292/00 aluminum bronze valve guide SI International makes for the LT5 cylinder head?


Sent from my iPhone using ZR-1 Net Registry (http://r.tapatalk.com/byo?rid=90383)
grahambehan
11-06-2019, 05:48 PM
Graham,
Do you have any experience with the VG 19292/00 aluminum bronze valve guide SI International makes for the LT5 cylinder head?


Sent from my iPhone using ZR-1 Net Registry (http://r.tapatalk.com/byo?rid=90383)

No sir, not in LT5 applications, but al bronze should be fine.

Graham
rkreigh
11-12-2019, 10:06 AM
on the old LSV we saw 3 guides that had noticeable wear after 106k. The other thing was the idler shaft for cam chains.

That was a bit of a surprise. Thanks Phil for all your help on this!