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Discussion Starter #1
Hi,

I found an engine/transmission combo I liked on Craigslist. I heard it running before pulling the motor from the car. It sounded fine. I checked the oil and it looked good.

My plan was to just drop the motor into my other 68 Camaro and run it.

When I pulled the valve cover, I noticed a lot of white foam in the tops of the valve covers. I attributed that to a bad PCV valve. When I drained the oil, it had a color that was different than the black I'm used to seeing. It didn't look like the typical "milky" oil that is typical of a coolant leak. It was more like the color of chocolate or dark chocolate milk.

I collected a sample of it in a plastic water bottle. When I let it sit, it turns blacker with the brownish oil settled at the bottom.

Part of me wants to just drop the motor into the car, change the oil, fix the PCV problem and see how it turns out.

I know that I should probably pull the heads but then I may be introducing a head gasket leak that wasn't there if I don't have the heads resurfaced. These are iron heads and I have a Starrett precision straight edge to check the heads so maybe that won't be such a problem. I might also pop the crank out and check the bearings while I've got it out. But then again... if it ain't broke, don't fix it.

Thoughts?



Thanks,
Sal
 

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Sal, Like you, part of me says run it but the mention of white foam or dark oil tells me to pull heads off while you got it out. Put it on and engine stand and open up. Look for problems . I would also pull pan and see whats in there also. Fix any leaks .
But , if you have any access to a leak down tester, to test leakage in valves or rings, I would do it. You may find more issues.
Knowing small blocks, I would also guess that you have some valve guides worn out , but pulling the head, popping off a couple of valve springs could verify that and while you are at it, new valve seals.
Never ends right? Like opening up a can of worms. All depends on how long and how dependable you want this motor to run.
Bad pcv valves don't cause foam.
 

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Discussion Starter #4
I think I'll do the leak down test. Compression test would be hard now that the engine is on the stand... no flywheel, etc.

I was planning on building a 383, but decided to throw a running 350 in the Camaro to get it on the road sooner. So this motor is really a stop-gap solution. I'd like it to last a couple years which will likely equate to around 10,000 miles.
 

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Discussion Starter #5
Now I'm more curious about the motor... Here is what I've found so far:

1) The clutch plate bots were loose when I took the motor apart (bad sign)
2) Someone plugged the water pump bypass hole in the block (someone thought they were building a race engine)
3) The oil galley plugs are tapped and plugged with threaded pipe plugs (good sign)
4) The harmonic balancer was only pressed on, there was no crank bolt (bad sign)
5) The heads are put on with ARP bolts (good sign)
6) One of the TORX screws that holds in the CAM plate (on front of engine) has the tip of a TORX bit broken off in it (bad sign)

Given what I've seen, I'm guessing whoever assembled this engine was a bit sloppy. I may pull the heads just to see more about what's going on in the bores. I'm guessing they would have only tapped and plugged the oil galleys if the block was out and in a machine shop... so maybe its been decked, bored and honed. Then again, you never know...
 

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Discussion Starter #7
I got the motor apart...

The cylinders looked good. I could still see some of the cross hatches from the hone. The block had been decked to 0.005 inches. I checked the deck with my straight edge and it looked great.



I couldn't find any signs of leaking through the head gasket. The intake gaskets also looked good.

Then I flipped the engine over and found trouble in the main bearings.. grooving and excessive wear. I also see debris embedded in the bearing.





The cam bearings looked great. Most of the rod bearings were fine. One rod bearing had excessive wear but no grooves. Another one of the rod bearings had some grooving.

I suppose I'm glad that I checked... though sometimes ignorance is bliss. I wonder how far it could have gone on those bearings.
 

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Coulda gone 5 years or 5 mins.

As long as it's apart change the cam bearings along with the rod and mains.
 

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Discussion Starter #9
Agreed. The motor is going to get hot tanked and then new cam bearings, rod bearings, main bearings and a new crank. The old crank was already 0.010 over and was scored pretty bad on the mains.
 

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Keep in mind, when some machine shops tank and boil a motor, they take out all plugs, including the one in the vertical oil passage near the oil pressure sender. Leave it out and you will have no if any oil pressure at start up. Some shops forget to put this back in.

Since your cly bore looks great, are you going back with new rings? If clearance is good, clean up bore with a ball hone.
Might even look for piston rings that are .005 over size and fit to cly bore if ring end gaps are over the standard.

Since block is decked, might check clearance on piston in hole, do the math and you might be able to use thin head gaskets. Just have to check that.
On the head gasket topic, depending on what heads you have, if there are cooling holes in the head that would allow you to match that opening with the block. Some felpro gaskets have that hole so all you have to do is match it on the block and drill block. This provides some extra cooling flow between the cly walls. Instructions come with the felpro 1010 gasket and maybe others.
 
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