Hopefully this weekend will be the big day and I will be firing up my rebuilt 239 "Y" block for the first time. I'm 95% sure I will be using Amsoil SAE 30 Break-in oil. I've always been to cheap to use Amsoil in my other vehicles but have decided to give this a try after some internet research. Please share your experiences with first time start-ups!

 

I use Royal Purple.

 

I hate to admit it but I use GM EOS engine oil supplement. Back in the day it was highly recommended for cam break in

 

There's a lot of thought that when mixed with a modern oil, it may not give the benefits it used to.

I don't know how much spring pressure the Y-blocks have, but I'd guess they aren't real high (for a stock engine). I'd trust a modern oil, as-is.

 

Fifteen years ago I used the parts house brand oil when I first fired up the rebuilt 300-6 in my '66 F-100. I did the 20 minutes at 2000 rpm bit and made sure everything got up to temp. Then I shut it off and changed the oil and filter. I figured during the first fire the filter quality was more important than the oil.

 

I'd recommend having someone there as an assistant, who knows what they are doing, or at least won't cause more problems ha ha. They can keep an eye for the leaks and other tasks as you do yours. On the other hand, try to avoid drawing a crowd of spectators, pets, little kids and other distractions. Have a fire extinguisher on hand. Have everything "preset" (like distributor ignition timing, carburetor) so the engine fires up right away and go straight to cam break-in instead of a marathon crank-fest trying to figure out why it won't start.

 

For my rebuilt 223 I used Brad Penn break in oil, 30 weight. Immediately ran at 2500 RPM for 20 minutes. No issues. Prior to firing, primed the oil system by using a drill with a hex shaft to spin the oil pump until oil flowed to the rockers. Not sure but Brad Penn break in oil may no longer be available.

 

I recently installed a new short block crate engine (twice, first had bad piston –long story). I used Valvoline conventional 20w-50 oil and Comp Cams Break-in Oil Additive. The engine has a roller cam and although the additive is best suited for flat tappet cams, I wanted the extra protection.

Here’s a quote from their web site:

Due to government regulations, in recent years oil manufacturers have removed the zinc and many of the other additives from their motor oil. However, using an “off-the-shelf” brand of oil during the critical break-in process can lead to a failure. Thus, COMP Cams® Engine Break-In Oil Additive is designed to extend the durability of internal engine components including camshafts, valve train components and all moving parts in your new or rebuilt engine. It does so by using a special blend of extreme pressure additives no longer available in “off-the-shelf” motor oils. COMP Cams® Engine Break-In Oil provides added protection during the break-in process and is compatible with any petroleum, synthetic or blended motor oil.

 

When I got my 223 back from the shop, they told me these engines are so low-performance fancy break-in oils aren't really needed. They suggested Valvoline VR1 30w. No fancy oils, no additives. 20 minutes @2000rpm.

Approximately 20,000 miles later, I have no oil burning, great response and good power(good enough from an engine rated at 120hp).


I think vintage car enthusiast spend too much time thinking about break-in oils for their cars that they then let spend weeks/months at a time not running. Letting a vehicle sit for extended periods with intermittent cold starts is one of the worst things you can do. Then you have the guys that cold-start their cars once a week to rev it up in their driveway, only to then put it right back in the garage and shut it off. Ouch.

 

I plan to have our Mechanic from our Fire Dept. Shop assist me. Or should I say, me assist him Him and two other guys maintain a fleet of 16 Fire Engines, 5 ladder trucks, 8 ambulances, and numerous other vehicles. I think I'm in good hands Plus, he's a little older so has a past history with these basic engines.

I agree some of this stuff is way over thought on these old trucks. So, I guess I'm guilty as charged. All part of the obsession! I admire every guy out there, from the guy that can barely keep his engine running to the guys that goes custom with with a brand new crate engine! It's all fun!

 

Perfect, sounds like you're tracking. I'm impressed you're keeping the 239, Y blocks don't get a whole lot of love in general, but the oddball sizes are the real orphans of the breed. More pics and maybe some video on the Banner Day, eh? hint hint

 

My engine builder recomended Brad Penn since it has zinc in it, plus the comp cams break in additive for extra protection. This was on a mild build 429.

 

Hey, watch what you say about 239 Yblocks! Oddball sizes!!!??? Dems fighten words!

 

Ha! Well usually everybody is advised to bail and install 292, and so the earlier Y blocks are almost scarce anymore, and parts are too?

 

Regardless of engine type and rating, it is best to use a specialty break-in oil. As mentioned, prep the engine to fire immediately as slow cranking will remove any assembly lubricants, especially from the camshaft.