Preparing a "refreshed engine" for first start.

Joined
Sep 5, 2003
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454
Location
Yuma, AZ
Moving along in an engine refresh for my FJ40. Original cam and lifters. 5/6 original pistons. One piston replaced due to damage by rings. All new piston rings. Cylinder head disassembled, cleaned and reassembled. Will do initial valve adjustment and set initial timing per FSM. Cylinders will be honed. Rings will be checked for correct gaps.

I've read about the oil and the zinc additives and multiple oil changes. Does any of this change due to piston rings and rod bearings being the only changes? Is the only main concern getting it fired, getting the RPMs up and running for 20 minutes or so to seat the rings? One oil change after that...more?
 
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Nov 25, 2014
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Western victoria Australia
You probably know this from reading about the zinc , it's important to not use oil with additives, friction modifiers . If the bores glaze , it's not possible to remedy , and will have to be honed again.
I would use cheap mineral oil, and avoid synthetic even if it has no additives.
 

Skreddy

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Feb 3, 2020
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Stanwood, WA
I use Valvoline VR1 in all my engines with flat tappet cams, even for break in (even in my roller cam big block and every harley I’ve had/built for others).
I think (though I’m no pro engine builder) that if using the same cam and lifters, no need to rev it up for 20 minutes on startup; that’s usually for cam break in. I’ve been told (and done) not to idle too long, get it running, make sure no leaks, then drive it to put load on it to seat the rings. Varying rpm’s. Lots of procedures and opinions on this though.
Usually in this scenario, I’ll get it running, timed and idling, then take it on the road and stay in say 2nd or 3rd gear (depending on application), increase speed up to 45-50 mph then let off and engine compression will slow me to 20 or so, then repeat a few times. Then, good or bad, I drive it like I stole it! That’s usually on bikes though.
 
Joined
Sep 5, 2003
Messages
454
Location
Yuma, AZ
Thank you for the replies. I'll source the dino oil and probably run it like Skreddy says - that seems to mirror some of what I've been able to find on the inter-webs.
 

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