Rebuilt head installed ready to start. When to change the oil? Now or run it first?

reweb67

Well-known member
I have the rebuilt head back on my 1967 Mustang 200 six engine. Have everything all hooked up and basically am ready to fire it up.

I pulled the head off because my valve guides were shot and oil was being sucked down into the cylinders and fouling out my plugs right away. Now I have new guides, new intake valves and positive stop oil seals. There was no blown head gasket or anything like that.

I'm thinking I should start the engine and let it run for 10 minutes or so and then change the oil? Or should I change it before starting it?

I did change the oil not long before I realized I needed to pull the head if that makes any difference.

Any opinions appreciated. Planning to get it started tomorrow so got to decide what is best. Thanks
 
too bad it wuz not drained when last shut down, still warm, and being diagnosed.

I'd do so now. Since it's not warm (oil, which carries away the contaminates, flows real good when warmer) it will hafta be drailed longer - to get more ou (several hrs)t. Or U could put a lght bulb (the ol incandescent) or 2 on it for a half day (actually touchin the metal motor). That could bring back some heat to facilitate a full drain...

Y put old oil in a new head? Esp @ 'start up' & 'first run'.

Hopefully the head wuz put 2gether w/assembly lube (only @ 'contact points') as these areas of metal-on-metal need friction reduction untill the pump @ bottom of motor gets a flow of lubricating oil up in that new head.

Any 1 have any proceedures on "Head Only Break In" proceedures? Must B smart to use the Brad Penn or other break in oils, the customary change out & refill, run-in RPMs etc...
 
Thanks for the reply.

I followed the instructions in the shop manual to remove and install the head and i did use engine assembly lube at the contact points as instructed in the manual. I does not say anything about changing the oil but just says basically - start the car and check for leaks -.

I think you are right though and it is best to change it now before I start it. Will have some nice new oil in the head.
 
Hi, I would change the oil now. Often times you get coolant dripping into the crank case when you pull the head. Good luck
 
B RON CO":31x2eglm said:
Hi, I would change the oil now. Often times you get coolant dripping into the crank case when you pull the head. Good luck

i agree, change the oil now before firing up the engine.
 
Yes, definitely change the oil before you start it up.
 
U sure, Seth?
 
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