I recently rebuilt my 22re engine. Everything went well and drove it 500 miles. Drained the oil. Then planned to adjust the valves. Pulled the cover and found the cam completely destroyed. This was a new head assembly w/ cam and new rockers. Admittedly it was a cheap one I found on Amazon.

Can anyone tell me what would cause this. I've read through the threads but not sure if this is just a failed cam or a symptom of something worse. I have purchased an LC cam and new set of rockers, but I'm terrified the new cam will have the same result.

I've rebuilt several engines and never seen anything like this before.

As you can see from the picture the damage was substantial. All of the lobes look the same. No significant wear on the bearing surfaces, just the lobes. Rockers were not significantly worn. They were scarred but not deformed or worn down.

Any help would be great. Thanks.

 

Cheap cams are often soft, this being said, even soft cams can often be broken in (burnished) and give long service.

Break in oil containing high zinc (ZDDP) is necessary to burnish new cams.

Are the oil dams in your head casting sound?? That is, are they able to pool sufficient oil to wet the cam lobes every revolution???

I have seen cheap heads where the oil dams are incomplete and ineffective.

I bought a dead 4Runner whose cam looked like yours and I put another inexpensive cam and rockers in it and

it's still running well after more than 15,000 miles. I broke it in on 10-30 Castrol GTX with addition of a common ZDDP additive.

Please let us know what you find and how your second try goes.

 

It's possible to assemble the rocker arm shafts wrong.

Then the oil holes don't align properly with the holes it the rocker arms and the lobes don't get enough oil......

Did it once on a 20R.

But I only screwed up one lobe.....

 

I had a newly built 20R eat an aftermarket cam that way. IIRC, it was a Crane cam and specified it needed 22R cam followers but the builder used the 20R followers. If you looked closely it was obvious the followers were dragging on the cam lobes.

 

You will probably want to change the head gasket also before bolting it back together.

 

After reading everyone's responses I looked at the valleys and dams. I'm missing two sections of dams. See below.





Was I given the wrong head? Did they cast it wrong?

 

Many of the new cast heads are junk.
Best to stick with a rebuilt genuine Toyota casting and Toyota valves, if you expect long service.

 

I don’t see what you are referring to in the photos. If “some” dams are missing in this casting and the only way the cam lobe gets lubed is by a “dipper” method(which I am not sure of) I would expect only the lobes in the non-pooling area to have worn. Yet you say the whole cam is wiped. What am I missing?

 

The dams are not the 'only way' the cam lobes are lubed, but the pools provide substantial lubrication from the first instant the engine is cranked.

The Toyota engineers did not include the dams for no reason.

Obviously there is oil flying everywhere when the engine is running.

The main cause of this cam lobe attrition is the failure of the cam lobe faces to burnish perfectly smooth, without any scuffing, in the very first minutes to an hour of operation.

The ZDDP in proper flat tappet break in oils facilitates this.

 

The oil soaked head is the new one. The clean head is my old cracked one which needed to be replaced. There is a small section of casting missing in the first and third valleys (front to back). Not sure if this would/could cause my problem.

I spoke to the guys at LC this morning. They are sending me a bunch of parts and hopefully it will work the second time. They do not believe the differences in the head casting would cause the issue. For the same reasons stated above. The whole cam is damaged not just the first and third set.

 

I’d like to know how the valve spring pressures compare. Kind of difficult to measure without the proper equipment but if there was a crude backyard method it would be interesting to learn what came on the new head.

 

I wound up replacing the cam, rocker arms, rocker arm shaft, head gasket, and head bolts. All parts were purchased from LCE. They gave me very good instructions on how to install and break in the new cam. Everything was installed per their directions and the truck ran fine. Today we did the 500 mile valve adjustment and oil change. Thankfully everything looked great. Cam is smooth and nothing looks worn at all. Only one intake and one exhaust valve needed very minor adjustment.

So... I have no idea what caused the cam failure the first time. A friend of mine (old timer who's built a lot of engines) took a look at everything and made the assumptions the cam wasn't hardened properly. He could not find any other cause for the cam failure. The failed parts were purchased from Amazon. My only suggestion to anyone with a similar issue is to buy quality parts the first time. In my case it would have been cheaper in the long run. The guys at LCE were very helpful and I appreciate everyone's responses. Thanks, Mike