I got this motor from a car with 87,000 miles on it and my motor with 150,000 miles on it looks like new compared to this thing. But ming has a spun rod bearing or main bearing (havent took it apart yet)...

Anyways, there is probly 1/4" to 1/2" in some spots of sludge just under the valvecovers on the replacement motor. Should I take the heads off and clean them? Some people say its best to leave it alone and some have said to clean the whole engine???

Also if I wanted to re ring the motor once I take the pistons out and put them back in can i reuse the rod bearings and just torque them back down to spec?
thanks

 

If you've got that much under the valve cover, then you've probably got more on the heads, in the lifter valley, under the intake manifold, and in the oil pan.

The only way to properly clean it is to completely disassemble the engine and clean the crud up. But, anything you get cleaned up short of that is a step forward.

 

what would be good to clean it with? After I scrape out as much as i can.

 

did you hear it run before you got it

if it ran fine then clean the outside

put a oil pan gasket timing gasket and valve cover gaskets on it while its out of the car

while your at it put a timing chain and oil pump on

if you are going to take it apart let the machine shop clean it

taking it apart means $$$$$

 

I learned the hard way about this just recently. Take the time to take it apart and clean it, most it will cost you is a gasket set. But in the end you'll have the peace of mind that there is nothing wrong with that motor before you put it in the car. I made that mistake, I put in a motor that I was told was rebuilt "about 1Kmiles ago" and after the head gasket blew on me I had to take it apart anyways. I knew something was fishy about it when I found caked junk on the bottom of the heads in the lifter valley but still didn't take it apart. Just pulled it apart in the last two weeks and found that at best they bored the block over 040 and still left pitting in the number 7 cylinder. I just pulled the heads apart in last couple days and found that all of the exhaust valves were pitted real bad on the valve seat area. I have no idea how this engine was running before, but I just got back from the craft shop on post and I had them regrind them for me just to be sure they were good before I put them back in. I also reground them to be sure that they were still straight too, since I've had problems with that before as well on a different motor.

In the end, I would strongly suggest to take the motor apart to take a look at everything after you have it cleaned up. I made the mistake of not doing it and it cost me more time and money in the end. At worst you find a ton of problems and decide not to put that "new" motor in the car and put that old one back in. At best you just spent $50 on a new gasket set and a couple days for the peice of mind that there is nothing wrong with the motor and that it's safe to use.