First oil after rebuild?

AlanEdwards

Registered User
I'm about to complete my short block rebuild. I was going to start out with Mobil 1 synthetic oil and Slick 50. But, I was advised not to install synthetic until I change the oil at 500 miles because it would be a waste of money. And, not to install Slick 50 until 2nd oil change at 3000 miles, to give the rings a chance to seat correctly. What do you guys think? Take care.
 
I have always just used a thick cheap organic oil and then changed it after a few hours of operation or 500 miles if you need to seat the rings.
 
After my engine rebuild, Motorcraft 5W-30 works the trick. I have seen the formulation charts on these oils and trust me, these grades are about the best thing you could put in that engine. It is also safer because changing oil after 500 miles is good but if for any reason you can't get the car in the shop for another 100 or so miles, the 10 grade oil still permits to be filtered, so it stands up to your specs even when you're just breakin her in and setting the rings. Also, I understand that red may be your favourite colour but just know that "chevy red" does not look good under the hood of an SC. Good luck with your project and hope it turns out well. (Although red does add a nice touch to brighten up the powerplants of these cars).
 
I just fired my engine up for the first time in 2 years (rebuilt the engine & trans) last Monday. I used a generic name brand (castrol) 5w-30, let her run for 15 mins in the garage then dropped the filter and the oil. Replaced with a new filter & oil and I am breaking her in (only running to 4k) until 500 miles, which will induce another filter / oil change. Then all bets are off, rings should be seated since I did not go for the moly rings (do it if you haven't bought your rings, after the first 15 mins they are seated!). If I knew that before I ordered the piston set, I would have gotten moly. Anyhow, I would go with a dino oil for at least a good 500-1500 miles to make sure the rings seat and your not throwing away expensive oil. I believe its better to run the dino oil for at least the first 1500 miles, but thats just me. :rolleyes:

If it breaks after 500 because of the beatings, its because something wasn't put together right!
 
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hmmm...

When we completely rebuilt my motor, we put it together with fully synthetic mobil 1, and ran it with that right from the get go. Car doesn't burn any oil, and is on about 10-15k already on the rebuild. Runs great :D
 
Thanks for suggestions above, you guys. A suggestion I got today from a guy that runs an auto machine shop, and has for many years, here in San Angelo, TX, said that I should start with Penzoil 40 WT, change it at 500 miles, then again at 3000, then again at 6000. Then I could do what I wanted after that, such as use Mobil 1 and put a quart of Slick 50 in at 6000.

He says that, yes, the rings will seat right away, but only 99%. I should wait until 6000 miles when it's COMPLETELY broken in, to use Mobil 1 and add a quart of Slick 50 at that oil change.

I questioned him about the 40 WT and he said that in the TX heat, the 40 WT would be best. And I'll be going to GA and to FL shortly, so just stick with 40 WT, of whatever brand I choose, from now on.

What do you guys think?
 
Wierd, I've never heard any mechanic or "real car guy" recommend slick 50, sure the autozone and walmart counter guys swear by it, but I've always read it was bad to use any of those "PFTEs" in your engine....

I'm surprised to hear a mcinist recommended it! have I been steered wrong all these years???
 
Sorry for any confusion. He didn't actually recommend using Slick 50 at 6000 miles. He actually said that I could do what I wanted to do at 6000, such as using synth and Slick 50, that I had already mentioned to him.

He also said that he's had customers, that he did the actual rebuild, that have been using Pennzoil 40 WT since day one of the rebuild, and they've got 400K on some of the engines.

I hope that clears it up.
 
Did you see the part about "The Infamous No Oil Demo"

I've seen them do this at the flea market/swap meets.

Of coure it will run all day, there is no load on it!

The worst part was that about the worn bores with the PFTE in the B&S tests....

I've always been afraid that that crap will clogg the filter, and gum up passages.
 
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