My cam lobes are done and need to rebuild engine head. What makes more sense to rebuild head or purchase new? What are the pros and cons including cost? There is a machine shop near me that is highly rated but I dont know the experience with 22REs. Also, what would cause this? Low oil pressure? Thanks for the advice.

 

In the first image, you are trying to show the tip of the lower cam lobe?

Looks like the wear starts right near the high point, this could be from improperly adjusted valve clearances. Either combined with lack of oil flow or causing the lack of flow, doesnt matter what pressure you have in the galley if theres no gap/clearance there is no flow so no cooling or lubrication. Aswell pre-ignition could be trying to slam that valve closed.


Bottom line, time for new rocker arms and a cam for sure.

 

What brand of motor oil have you been using??? How many miles has the engine run???

The cam lobes are oiled by dipping into oil that is held in dams in the top of the head.

I have seen an aftermarket head where these oil dams would not hold oil as the OEM heads do.

 

Also seen soft aftermarket cams. Or bad break-in and let to an premature problem as well

 

Co_94_PU...yes that is the tip.

The engine has 171K miles. It runs sluggish as a result of the jacked up cams. I dont recall the motor oil brand that I used, it was a Jiffy lube over 75K miles oil which I believe is Penzoil.

Going to definitely take it to a machine shop for a rebuild.

 

Your rod bearings and main bearings probably do not look much better. I just dealt with this. loose timing chain tensioner, flat cam, worn bearings, wasted crank. Even with new cam, no oil pressure, engine still ran great, just smoked. I would rebuild.

 

Decided to rebuild both the head and engine. Been driving it for two weeks now and drives much better. Can climb hills without problems and accelerates easier. So far looking good and just need to continue driving more to break in the engine. The only thing that stands out is the engine temp indicator gets to operating temp very quickly when I start the truck.

 

I read post by one of "those guys", Ted Todd or maybe Jim, the other day.

They were discussing how the tip of the rocker arm shouldn't be in contact with the cam as it causes premature wear..

Essentially what this translates to is if the rocker arm surface is overly flat there is to much contact pressure put on the cam lobe.
(Edit)
The test for this is to inspect the contact pattern, the solution is to replace the rocker.

 

Would that be caused by a loose timing chain?

Below are some pics of the replaced parts.

 

Updated the previous post.

I don't think the chain has relevance for that issue, but you may have been asking about some things in you last set of photos.