compression check on old engine

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Ontheboulder

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hey guys, gonna hook up a starter and check compression on this new to me 350 i picked up. the cylinder will probably need a shot of oil since it has been awhile so what to use?? marvel mystery,ATF regular oil?? also gonna put a drill on the oil pump to get an idea of oil pressure. any thoughts , ideas,do's and don'ts?? thanks
 

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bucket

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I'd just put a drill on it and verify oil pressure at all. I don't believe a pressure reading is going to mean much, compared to pressure with the engine actually running and driving.

I also wouldn't worry about putting oil in the cylinders, unless you have cylinders with very low compression.
 

75gmck25

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A squirt of oil in each cylinder will never hurt, and then use a drill to run the pump and verify it works. With the plugs out you should be able to turn it over by hand, either using are the flywheel or crank adapter, and make sure it turns over smoothly.

Pull the valve covers and adjust/set the valve lash. Checking compression is also a good idea, just to see that that compression is even cross cylinders.
 

Ontheboulder

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I'd just put a drill on it and verify oil pressure at all. I don't believe a pressure reading is going to mean much, compared to pressure with the engine actually running and driving.

I also wouldn't worry about putting oil in the cylinders, unless you have cylinders with very low compression.
thanks I was just planning on a check, then after that probably just go ahead and ring and bearing the motor, the guy i got it from said he rotated and oiled - drill motor on the pump- a couple times a year. supposedly only 90K on the engine so we shall see. I just want to check out of my own curiosity
 

Ontheboulder

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A squirt of oil in each cylinder will never hurt, and then use a drill to run the pump and verify it works. With the plugs out you should be able to turn it over by hand, either using are the flywheel or crank adapter, and make sure it turns over smoothly.

Pull the valve covers and adjust/set the valve lash. Checking compression is also a good idea, just to see that that compression is even cross cylinders.
I am gonna get a mech oil pressure gauge and just see what the pressure is out of curiosity, definetly gonna get a new pump before it goes back in the truck
 

Ricko1966

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I am gonna get a mech oil pressure gauge and just see what the pressure is out of curiosity, definetly gonna get a new pump before it goes back in the truck
That's not going to tell you anything other than you have pressure or you don't have pressure. If you have a sender for a light screw it in put a multimeter on ohms to the sender and on the block see if you can work the sender, should be 0 ohms resistance stopped and infinite with oil pump running. Your drill motor IDK. Oil pump turns at 1/2 crank speed so if you know your drills rpms double that to see oil pressure at engine rpm.but the values change with heat. I'd make sure it could work the light or gauge sender and call it a day. I also think it would faster, easier and more accurate to blow 100 psi shop air in each cylinder. Make sure air stays in the cylinders not out the tailpipe,intake,water pump or intake.
 
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