Hi all,


what kind of motor oil (brand) is good to use for a brand new motor just to break in the engine period?

Thank you.

 

There is no one recommended brand of oil, but I would NOT use a synthetic until break-in is completed. Just use the appropriate viscosity for your climate and temps. The critical thing IMO during break-in is to change it often with a quality filter.
FWIW after my rebuild I changed at the 100, 500 mile; 1000 mile and 2000 mile marks before resuming my normal interval of 1800 to 2000 miles between changes. That's with all new bearings as well as hard seals. Others may have different takes...but you get the idea.

 

Cam at Pettit recommended Valvoline 20w50 VR1 Racing oil to me.

 

I dont run an OMP so i run mobil 1 syn, but heres a good debate thread you might want to read through.
https://www.rx7club.com/showthread.p...%2Bsyn+%2Bdino

 

+1 for Valvoline VR1 Racing 20w-50. It has a high zinc & phosphorous (.14 zinc/.13 phos)content, plus it is conventional so it's OK to use with the OMP.

 

I'm using Idemitsu Rotary Engine Oil.

there is a good reason for it, read this:
http://www.mazdatrix.com/faq/synthetc.htm

 

I know it's not apparent in his thread title, but the OP was asking what kind of oil to use for breaking in a new engine. Not what to use routinely. Given the frequency of changing, cheap conventional oil would be my choice.

 

Why would you ask opinions here? Don't you trust your engine builder?

 

when my car's engine rebuilt, the builder (Rick's Rotary) used 10 / 30 castrol oil and recommended to keep rpm under 4000. then change oil at 1000miles. after that just I used Idemitsu.

 

I agree that VR1 is good stuff.

What makes you think it's not OK to use synthetic with an OMP?

 

Vr1 20w-50, it's one of the only clean burning oils on the market (ie ashless) and it's the only thing I use. Though it's little known, using the wrong oil in these engines can and does cause detonation.

-J

 

Care to expound on that Big J, King of the Swampland ?

Not to debunk your theory, but back in 2000-2001 I ran VR1 20w50 exclusively and blew 7 engines (yes, seven) due to a combination of bad luck, inexperience/naivete, shitty garbage Hurley apex seals, and bad advice from my engine builder.

 

thanks you all for responding. i forgot to mention that... I'm also running BNR stage 3 Turbos... which i remember correctly.. i can't use full synthetic oil with the bnr stage 3 turbos. Unless changing some internal parts in order to run synthetic.

 

I'm with you Rich. Sounds like BS or too much alcohol talking

 

i was using this before i ever met cam, he was happy to hear i was using it.

 

Delo 15-40 (Chevron), Delvac (Mobile), Formula Shell, Motorcraft (yes, you read that correctly--these are all dino fleet oils) all have good add packs, esp. for the rotary. In addition to ZDDP, those mentioned also have significant boron and moly content; both of which reduce friction and promote wear reduction. (Many oils don't have either.)

The Delo can be had for 10 or $11 gal at walmart and is an excellent deal. It has about the best add pack in the industry (including high zinc & phosphorus; about the same as the VR1). I agree that VR1 is good, I have used it myself; however, overall I think Delo formulation is better.

At these bargain prices, there should be no reason not to change your oil every 3 to 3,500 miles. This is not a fault of the oil, but rather of fuel dilution, which is characteristic of the rotary--and carbureted piston engines. (The dilution can be minimized by making sure you oil system has a thermostat that will let the temps get up to at least 200 deg F on a regular basis, which will help flash off the volatiles, i.e., gasoline.)

Use a good oil filter: Mobile 1 #104, Purolator Pure One, Fram ToughGard (yes, I said the F word) are all decent filters with good media in them. I have used all of them, and cut them open for analysis as well. You really only need to change the oil filter at every other oil change BTW, the depth gradient & blended media will generally improve in efficiency over the life of the filter, so even at 7000miles you are only at half the rated life of the filter.

 

Personally I've always used Silkolene PRO S 5W-40 Ester Synthetic Oil. But I am still on my original engine internals, so have never had to break one in...Never had any issues with it..Except for the fact its more expensive than most oils.

 

How long have you been using that?
I've been using Valvoline 20w50 VR1 Racing oil for a long time. And swear
by it. I've read a lot on the Idemitsu oil. But I've used synthetic in the past.
And Spent some days getting carbon out of the seals. It stuck every seal on
both rotors. So I have been kind of bias since then. At least if your still using
stock omp.

 

I've taken apart many engines that were run on synthetic oil (usually Mobil1, not idemitsu) and stock OMP and there was no abnormal carbon buildup.

I think the amount of carbon is related more to idle/cruise AFR and time spent at high rpm (or lack thereof really) than anything else. Just my opinion

 

^Still way off-topic, but what he said.
I exclusively ran synthetic (Mobil 1) for ~40,000 miles on stock OMP before a coolant seal failure. During rebuild I had no unusual carbon build-up either. And except for an occasional autocross (during which I also pre-mixed a little 2-cycle) it's street driven...probably what most would consider pretty conservatively.

 

I run 20w-50 Castrol GTX

 

+1, I think you assertions are probably right.