Valve problem

[BAlex1990zR1]

My valve guide (not seal) has came loose and slide down valve stem . Anyone every seen this or fixed

[oricale]

This seems to be due to the locating ring slipping...however suprising that it would slide down(would suggest other issues with the guide):

The only correct repair is to pull head, cam cover cam, lifters and springs above the guides and inspect all guides for movement and then if all is good get the guide out and replace...however since they are 90' heads have a head job done and install seals since the 90's didnt come with them.

Im curious if the guide "floated" for a bit after it fell riding on the valve.?..wonder if there is any damage to the guide boss

Dempsey

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[Hib Halverson]

If you have a head with a "loose guide", as "oricale" suggests above, the only solution is to remove the head replace the guide and, if necessary, repair the head.

With an LT5, if the heads are coming off, it's best to pull the engine.

Also, if you have one loose quide, you want to check all 15 others. As "oricale" suggests, you might as well service the heads and, while your at it, install seals on the exhaust valves. '90s didn't have them and you can reduce oil use if you add exhaust stem seals.

[Jagdpanzer]

First I’ve heard of this happening but not surprised given the LT 5 guide design. The guide relies on a retainer clip ring to prevent the guide from being installed to far during factory assembly or from dropping down the bore during operation. Initial installation is with a interference fit which, if within proper tolerance, should retain the guide for the life of the engine. However, if the guide fit was on the loose side then I could imagine the valve operation working the guide loose and eventually pushing the guide past the retainer ring like you have experienced. No question the head will have to come off for repair. Most likely the guide bore in the head will have to be machined out and a oversized OD guide installed. Usual work for a competent motor machine shop.


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[Jagdpanzer]

Like the others have said good time to do a valve job and install exhaust stem seals.

[Jagdpanzer]

Here is what the valve guide looks like with and without the retainer ring https://uploads.tapatalk-cdn.com/20171231/eefd80f4b2520c12ae7ca82cc3dfc845.jpg

And in the head
https://uploads.tapatalk-cdn.com/20180101/9c2a308d09078a2561d3052b528b8630.jpg


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[BAlex1990zR1]

With no timing marks
What the best way to remove the head?