Picked up a 3.0 to put in my 94 4runner. I was changing the valve cover gaskets before I put it in and noticed milkshake on the tops of the cam bolts. I was told this engine was rebuilt and then reverse went out. The truck sat for 2 years, the owner died and then the guy I got it from acquired it. He said he drove it home no issues but it was only like a mile or so away. He is using the frame for a different project and I got the engine from him. Anyways, this is what I found when I cracked the valve cover gaskets. Blown head gasket or moisture from sitting? Cams seem rusty too.

 

You didn't pop the valve covers before you bought it? Do a compression test on it

 

No I didnt have time or tools to do that when i looked at it. Got it from a police officer he was really cool and seemed to know his stuff although that could account for nothing. How would I do it? Never done a compression test with engine out of the vehicle. I have one of those triggers you hook up to the starter though.

 

The same as in the vehicle, just make sure the engine is secured

 

You have more things to worry about, besides the compression!
The rusty cams are just one.

 

X2 some of that rust looks deep. Might not be save-able.

 

Check the oil in the pan, Looks good do a compression test.


If you cant return it and the the above is good, I say go for it.

 

Its just from sitting. There is a little surface rust on the lobes....probably be fine. The factory hardening goes a little deeper than that rust. Put it in and run it. fix any gaskets etc on the outside while the motor is out.
Dont listen to the doom sayers till its running and you see smoke or hear knocking.

 

Yea I'm going to run it and see what happens. Got the crossover pipe mod done so it's going in. Hopefully it wont be too difficult with the exhaust attached like it is lol.

 

Yes I have to agree just from sitting.

Run it put in some cheap Walmart oil run it till it gets up to temperature change oil and filter looking close at the oil.

It is a moot point because when I sell things it is most often very cheap like scrap price .

I don`t think I would let just anyone do a compression test on any of my engines .

 

Doom sayer. that's funniny.
Did I say op was screwed? no. But I sure didn't say to 'go for it' and let the consequences-be-damned either.
I don't give a crap if the hardening goes to the center of the cams. These are pitted. I don't even have to get my microscope out...


Just sayin they need to do a little prep tlc on OTHER things besides the original 'compression test' question...
You do realize that Iron oxide is just one of several different grits used to make sand paper?
This motor may very well be savable, but blindly spinning it over NOW sure won't do it any good.

 

Once you get some fresh oil lubricating those cams again that rust will work itself off. Having silky smooth cams is nice, but that will still run just fine. These engines are tougher than people give credit for.

 

Update: The engine runs great! Most of the stuff on the cams came right off. Doesnt over heat, holds fluids.. Smoked like crazy for like 15 mins after first start up but now theres nothing. Flushed the coolant passages then filled it up with water without the t-stat and added some mystery oil to the crankcase. Ran it for 20 mins then drained them both and filled up with 50/50 and a fresh oil change. Just took it for a spin down the road and no issues except its slowww. Got an automatic trans, 4.88s and bald 32x11.50s. Probably going to swap the 31s from my other 4runner.

 

eh? I'd be like "go. to. hell." if some random ape tried to get under the valve covers to satisfy his curiosity. unless, of course, he agreed ahead of time to adjust the valves.

 

Then the way I look at it your hiding something and I wouldn't buy it.