^^^ You and me both...


Sounds like me...

 

I am convinced after reading this entire thread and several other oil and engine failure threads...

That I want to use Mobil 1 0w-40. But I am concerned about switching from Dino to synthetic in a car I just bought with 106K on it that had the short block replaced at 77K. I am concerned because of the thread I read about one person's engine rebuild by MazMart where it seems the switch to synthetic may have caused the seals to leak.

How valid is this concern valid in my case?

 

in an engine with ~30,000 miles on it? Not at all.

 

Do you know that mobil 1 is possibly the only bad synthetic choice for a rotary nowadays?
It poorly mixes with fuel. Other synthetics are 100% fine just do a quick search and you'll see the best ones for yourself

 

??? What????

I know all about Rotary Gods opinion about Mobil1 and the source of his concerns. And I'm honestly not sure where I stand on that issue.

However, your comment above astounds me. Have any facts or quotes to back that up? ...because it just seems absurd to me.

Not just the statement on itself, but the assumption that Mobil1 is SO much different than all other synthetics when it comes to mixing with fuel.

It amazes me how much oil is considered almost to be this mythical magical substance with all sorts of properties beyond the realm of reality.

 

A search reveals rotarygod's opinions and quotes about Mazda personalities discarding it.
I can attest what i have seen first hand. That is higher wear rates than engines running on 5w30 dexelia or 5w30 oil of the "common" brands here.
Mobil 1 is fairly common as a performance lubricant in Italy so a lot of douchebags just pour it in, then after 40.000kms start crying and need a rebuild

 

I did see that in the thread but that a lot of people were using it anyway...

 

Oh come on now! I've pumped many gallons of different kinds of oils, some before or after gasoline, and a few times I sure wish you were right.

It's possible that a few additives that have alcohols in them don't, but pretty much every motor oil in the stores will straight up mix as soon as poured and not separate.

Please someone post a pic and prove me wrong.

And I mean pure gasoline or even diesel.

One one more note, I don't see 5w30 oil testing that good on BITOG, but many of the high performance factories in Europe are filling with and recommending 0w40; sort of the lastest in mo technology.

 

I'm thinking that the biggest killer of the renesis is the bad coils which turns all the unfired gas into carbon or heat in the cat.

Mine were compromised at 23k, so I put on the BHR ign.

I only knew to do it by reading all the failures from misfires on this forum; the manual doesn't say a word about it.

I wouldn't run 5w20 except to break in, but I don't think you can ruin the renesis with almost any higher weight oil as long as it fires right.

 

I can't answer your question, but I can tell you that having an oil tested to meet the SAE standards is frackin' expensive! I worked in one of the test labs many years ago. There is a lot more to it than one might guess. I was amazed.

 

Well myself and others have tested Mobil1 a few times and it performs best in my car, so I use it (0W-40). In a way I am glad I got a new motor at 96,000 and then started with Mobil1, premixing, SOHN adapter, Mazmart OP kit, Catless midpipe, and BHR Ignition.

 

Question for you guys. So I use an oil extractor to change oil. Works the ***** but I am afraid of cross contamination when grabbing a sample to send to BSL. Question is, can i just rinse out the extractor tank and grab a sample and assume that there wont be too much contamination? I would prefer not having to go through the drain plug only because I now have my temp sensor there and dont want to much around with it.

 

I use the same and since I empty it after each use, I don't worry about it. Any small amount left is as the bottom so when you pour your sample it should be okay.

 

Good deal, figured as much but wanted to make sure. Thanks for the quick response

 

Wow, I have not read this thread in a long long time... My engine on my 2004 has been problem free so far (knock on wood) and I use dino 5w-20 and change every 3-4K miles. My car has 86K miles on it. Should I continue to do this since it is working fine so far or use a 0-40 synthetic oil? hmm

 

Butt dyno is NOT an accurate way to check engine problem.

at your odo, it doesn't matter anymore. just use whatever till it blows up.

 

Switching to synthetic would be pointless at this point.

 

I read some interesting things over at BITOG while researching oils for my 8. I was reading an oil analysis done on a BMW 335i with 9,000 miles on the BMW brand 5w30 synthetic oil. (Group III) Those twin turbocharged motors commonly push oil temperatures above 250F. This particular car pushed temps upwards of 275F! However, the oil analysis done shows that the oil still had plenty of life and the engine was wearing nicely. I hear a lot of concern for the Renesis when oil temps go above 220F. It seems to me that a modern, good quality oil will have no problem dealing with heat like that. I'm curious why there is so much concern over 1. Oil temps and 2. Using oil as thick as 20w50 as some deem 5w30 too "thin" because the renesis gets too "hot". Please comment on this. Thanks!

-Lawrence

 

...

oh no you didn't.

that topic has been discussed like 50 thousand times.

 

Sorry not trying to stir anything up. From all the reading that I've done it just seems like a common misconception that I wanted to clear up. I found the results of the oil analysis surprising myself. And if I'm not mistaken I think I've seen your screen name pop up on BITOG also. I'm sure you're well versed on oil

 

one thing you gotta remember is that Piston engine is not the same as us. Rotary engines have different requirements.

so something works for them does not mean will work for us.

 

You cannot equally compare data in piston engines to data in rotary engines.


One reason for concern is that unlike a piston motor, in a rotary engine about 1/3 of the engine heat is release through the oil coolers. The general rule of thumb from what I have read is that oil temps in a rotary should not exceed 205-210F (seems low to me but lower is better). You also have to remember that oil is sprayed through the Eccentric shaft on the insides of the rotors themselves to cool the inside of the rotors so it seems the cooler the oil, the better.

 

I have premixed since I got the car at around 16K miles on it... I will cross my fingers it blows up a few years from now lol.. or maybe i should wish it happens sooner to get a new engine before the warranty ends? lol

 

I'm going to keep running synthetic but I keep lingering on the thought of my engine failing, and then taking it to the dealership, and then they say "We won't give you a new engine because you used synthetic".

Would I be able to use that whole "Prove that synthetic oil was the cause otherwise you must honor my warranty" thing on them? After reading through this thread I still see no reasonf or me to switch to conventional but maybe I should if my engine decides to crap out on me in five years...

 

First you show them the line in the manual that says "synthetic not recommended" and say that all it says is that its not recommended, doesn't say "synthetic will void warranty" or "conventional is required"

Then show them the Moss act that states they must explicitly prove that what they claim was the root cause of failuer.