GP1200R

since there have been so many synthetic oil threads on this forum I think we should all get an oil analysis done and settle this once and for all

I would also like to know if Rich's theory about precise corner/apex seal clearance really mitigates fuel dilution....fuel dilution seems to be a very common, if not ubiquitous, problem with FDs

check this site http://www.oaitesting.com/ (division of Amsoil)

at the bottom of the page is a list of the analytical parameters available (as well as pricing)...the primary tests I am interested in are viscosity and oil dilution....there are plenty of other useful tests (like the four ball wear test), but they get pricey

if we can get a group of FD owners together to get their oil analyzed we could generate a nice little database of info, such as:

- fuel dilution for engines of various mileage (e.g. <30k, 30k-60k, 60k-90k, +90k)

- viscosity of the oil after 3k miles (normal oil change interval), which would help to determine whether synthetics really hold up better in a turbocharged rotary

I sent this Dan Horn guy an email to see what other standard tests he usually recommends, but I wanted to see if there is any interest (I'm going to get it done even if no one else is interested, so I'll update this thread after the results come in)

thanks for reading

DomFD3S

You would also have to factor in things like:

Brand of oil filter (along w/ filtration element type).
Possible brand of fuel filter (whether OEM or not).
When was the last time, fuel filter was replaced.
Whether "new" engine was standard reman or complete rebuild from an engine builder.

Also, have to ensure that oil coolers are properly flushed and cleaned prior to any of this testing, as old oil remaining in an oil cooler could throw off the "ideal" results.

Kento

I'd have to agree. There are way too many variables involved (especially engine condition from vehicle to vehicle) to be able to come to any sort of blanket conclusion on oils based simply on a lab analysis from even 10 cars.

Even something like the four-ball wear test in and of itself cannot be the basis for a judgement on oil. There are too many other considerations that a motor oil must endure in the overall internal environment of an engine.

All you can do is gather as much imperical data as you can, and make your own decision.

For what it's worth, the next issue of Sport Rider Magazine will have a fairly comprehensive lab test on oils (although they are motorcycle-specific, but a few car oils were included in the tests), plus a dyno-test with several oils to see if there's any hp difference at all. We also performed a four-ball wear test on several oils (yes, it's expensive, so we couldn't do too many), and even a shear test (measuring viscosity degradation of several oils over time after exposure to the "shearing" action of meshing gears-- similar to what probably occurs in the eccentric shaft/rotor area of a rotary). Should be on the newstands soon.

turbojeff

iTrader: (30)

I've got 4 separate oil analysis done on my 93 R1 if your interested...

I can't imagine why we need to know what type of fuel filter the car has though.

Oil coolers weren't flushed, but with 4 consecutive oil changes I think we can establish a pattern.

GP1200R

You would also have to factor in things like:

Brand of oil filter (along w/ filtration element type).

the brand/type of oil filter has little or no effect on viscosity degradation or fuel dilution (the two parameters I am most interested in), although it obviously would effect particulate entrainment

Possible brand of fuel filter (whether OEM or not).
When was the last time, fuel filter was replaced.

again, neither of those has any effect on fuel dilution in the ENGINE OIL...think about it

Whether "new" engine was standard reman or complete rebuild from an engine builder.

that would be useful information

Also, have to ensure that oil coolers are properly flushed and cleaned prior to any of this testing, as old oil remaining in an oil cooler could throw off the "ideal" results

the analysis should be representative of a "normal" oil change....most people (I would say almost none) flush their oil cooler during an oil change

GP1200R

I've got 4 separate oil analysis done on my 93 R1 if your interested...

sure!

post the data with how many miles you have on your engine since a rebuild, type/quality of rebuild, type of oil (dino/syth), and mileage on the oil

GP1200R

I'd have to agree. There are way too many variables involved (especially engine condition from vehicle to vehicle) to be able to come to any sort of blanket conclusion on oils based simply on a lab analysis from even 10 cars.

I'm not looking for a "blanket conclusion", more of a statistical analysis of some of the variables

Even something like the four-ball wear test in and of itself cannot be the basis for a judgement on oil. There are too many other considerations in the overall internal environment of an engine.

true....my primary interest is fuel dilution in turbocharged rotaries

All you can do is gather as much imperical data as you can, and make your own decision.

For what it's worth, the next issue of Sport Rider Magazine will have a fairly comprehensive lab test on oils (although they are motorcycle-specific, but a few car oils were included in the tests), plus a dyno-test with several oils to see if there's any hp difference at all. We also performed a four-ball wear test on several oils (yes, it's expensive, so we couldn't do too many), and even a shear test (measuring viscosity degradation of several oils over time after exposure to the "shearing" action of meshing gears-- similar to what probably occurs in the eccentric shaft/rotor area of a rotary). Should be on the newstands soon.

as an avid Sport Rider reader and YZF-R1 owner, I'm looking forward to it, Mr. Kenitsugu

DomFD3S

You also have to figure in the current mileage for the particular engine. An engine that is near it's last legs (in terms of expected rebuild time) may give different results. Especially one that is leaking coolant into the oil for example.

And yes, regarding the oil filter, I was mentioning it regarding particule contamination.

Good luck w/ this testing...

ZeroBanger

There should be no debate as to what type of oil to run in a FD. We do know that synthetic is better for the turbo. With that in mind:

1) Turbo costs more than the engine.
2) The 13B-Rew is not likely to survive past the point where the Pro's or Con's of either oil type (Synthetic or Dino juice) would come into play.

GP1200R

There should be no debate as to what type of oil to run in a FD. We do know that synthetic is better for the turbo. With that in mind:

1) Turbo costs more than the engine.
2) The 13B-Rew is not likely to survive past the point where the Pro's or Con's of either oil type (Synthetic or Dino juice) would come into play.

I'm all for synthetics, and I'll be interested to see the results of the dyno testing in the new Sport Rider

but the overall point is this: is you have excessive blow-by (which these cars are notorious for) and about 10% fuel dilution of the oil, I don't care if you run the same **** they put in a Ferrari Enzo, the performance of the oil is still going to suffer dramatically

so the overall objective is to determine how fuel dilution relates to history and/or quality of engine rebuild....based on what Rich (Goodfellas) is telling me, it makes a big difference, and I want to see if he's right....he claims he has no gas smell in his oil

go out to your car right now, pull the dipstick, and take a big whiff

GP1200R

http://www.usoilcheck.com/fuel_dilution.htm

GoodfellaFD3S

iTrader: (213)

It's not a theory, it's a fact. If your side seals are improperly clearanced, and there are gaps in between your side seals and corner seals, you're going to get the by-products of the combustion process into your oil.
I'm not going into any more detail, b/c I am by no means an expert on the subject and don't want to talk out of my *** .

Now, in my opinion all boosted rotaries are going to get some gas in their oil, but it should be a minor amount--not enough to make 20w50 look like 5 weight on the dipstick. The difference between my current motor and my last motor is like night and day. One other phenomenon I noticed--my oil level never went down.....could it be b/c of all the fuel being added?

That said, I think oil analysis is an excellent idea. I've actually been thinking of doing it myself--here's another link:

http://blackstone-labs.com/index.html

take it easy--

GP1200R

hey Rich, what was the break-in period on your new motor before you went to Mobil 1? improper break in could also effect poor sealing

I guess that's yet another controversy: how long to break-in the engine before switching to synthetic....I switched at 300 miles and I may need to put dino juice back in for awhile

GoodfellaFD3S

iTrader: (213)

I've typically went 500 miles with dyno, change oil, 1000 more miles with dino, then switch to synth.

It all depends on how thorough of a rebuild it is, and how new all the components are. We've had guys that put 2000 miles on a motor, blew it, and brought it to us to rebuild. After she's back on the road, a 1500 mile break in is prolly overkill.

GP1200R

I've got two new housings and new seals of course

turbojeff

iTrader: (30)

Original motor, 20W-50 oil, OEM oil filter.

turbojeff

iTrader: (30)

Doesn't seem to want to attach...

Does anyone want to host a small pics for me? It has 4 oil analysis done on my car, mileage was around 50K at the time.

GP1200R

just summarize the key parameters....how many miles on the oil? dino or syth? what brand?

rex u.k

may be a poll would be a good idea,just to see what people are using synth. or non synth.(if this hasn't already been done) what are your experiences? do you have any problems with carbon buid when using synthetic?

80-CU.IN.T

Not a bad idea - Major factors - Average oil temp, highest oil temp and for how long, oil or water cooled turbo, how much boost you are running and how often you see that boost level. There are many different variables to consider but a basic data base can be established. I am currently running Royal Purple 10 - 40 racing with their 2 stroke oil as a pre-mix. OPM disconnected. I change oil & filter every 800 miles.

GoodfellaFD3S

iTrader: (213)

Damn, man. Your dad must own Royal Purple or something......that's some serious cash on oil

RonKMiller

This of course will never put the thread to rest, but here's Mazadspeeds' official recommendation for race engines:

" A proper and careful break-in period for a newly rebuilt engine is extremely important. The break-in procedures listed on the following page may seem excessive. However, an engine that has been broken in properly will see more power across the engine's rpm range and longer service life than a comparable engine that has not. If using the old bearings, please note the difference in hours and mileage requirements for the break-in period.

(side note: OLD rotor bearings that are within spec are PREFERRED over new bearings.)

When breaking in any engine (race or stock), use a low ash content, mineral-based racing oil (20W or 30W). After the break-in period, change to a mineral or synthetic racing oil (30W or 40W).

Using a dynamometer for engine break-in is preferred. If you do not have access to a "Dyno," use the mileage break-in figures on the following table. The engine should first be run at idle for 30-45 minutes. During this time, be sure to check for leaks and keep an eye on the gauges. Ideally, for the first 100 miles (depending on use of new or used bearings), avoid operating the engine above 5000 rpm or under heavy load.

From 100-200 miles, gradually increase rpm, but never allow the engine to approach red line. Beyond 200 miles we recommend only short bursts of power approaching red line for 100 miles. At this point, change the break-in engine oil. The engine break-in period is now complete."

In my opinion, a longer, "kinder and gentler" break-in period is appropriate for street engines. It is VERY important to run the engine to redline once in a while during break-in in order to allow all the seals to seat hard. I think Rich's recommendations are right on the money for 99% of us.

GP1200R

I put dino fluid back in last night and I'm going to run it for another 500 miles before going back to Mobil 1, and then see how the smell is affected (if at all)

the seals of a rotary engine may take longer to "seat" than piston rings...I've heard speculation about this

anything that can be done to mitigate fuel dilution is extremely important to the overall life of the engine....fuel dilution greatly reduces oil performance and it seems to be very common in FDs

http://www.scuderiaciriani.com/rx7/oil.html

Here are the survey results with new responses since the last posting. There were a total of 39 responses to various parts of the survey. Here we go:

Gasoline smell:
Slight/None: 31%
Noticeable: 44%
Strong: 25%

Oil usage, miles/quart, among "Slight/None" gasoline smell:
Less than 1000: 0%
1000-3000: 36%
3001-6000: 27%
More than 6000 or no usage: 27%
Negative consumption: 0%
No answer: 9%

Oil usage, miles/quart, among "Noticeable" gasoline smell:
Less than 1000: 0%
1000-3000 miles: 12%
3001-6000 miles:18%
More than 6000 or no usage: 47%
Negative consumption: 6%
No answer: 18%

Oil usage, miles/quart among "Strong" gasoline smell:
Less than 1000: 10%
1000-3000 miles: 20%
3001-6000 miles: 10%
More than 6000 or no usage: 30%
Negative consumption: 20%
No answer: 10%

Oil usage, miles/quart among "Noticeable" or "Strong" gasoline smell:
Less than 1000: 4%
1000-3000 miles: 15%
3001-6000 miles: 15%
More than 6000 or no usage: 41%
Negative consumption: 11%
No answer: 15%

Gas smell, among those reporting less than 6000 miles/quart consumption:
Slight: 44%
Noticeable: 31%
Strong: 25%

Gas smell, among those reporting 6000+ oil consumption (including
negative):
Slight: 18%
Noticeable: 53%
Strong: 29%

There was still no noticeable pattern as regards miles since last change, oil weight/type, style or length of driving, mileage on the engine, and so forth.

So there is (still) a decent correlation between gasoline smell and lack of oil consumption. But what makes those engines which use oil as expected, different from those that use very little or no oil? Still a mystery.

Also interesting is the fact that 2 of 3 persons reporting negative consumption have had major engine failures (Martin Crane, Dave Roberts). So if you see your oil level going UP, look out!


Date: Wed, 07 Jun 2000 00:39:40 -0700
From: Max Cooper (max@maxcooper.com)

There is reasonably clear evidence that some of these cars have a lot of blow-by. The evidence of which I speak is that the oil often smells strongly of gas when changed. And some people even have their oil level INCREASE despite the fact that oil is injected which should cause the level to decrease, which makes me think that a lot of blow-by is going into the oil.

I am by no means an expert on this subject, but there does seem to be a large opportunity for blow-by relative to a piston engine. On a piston engine, gas can blow by the piston rings, which is not a lot of space relative to the combustion chamber size. On a rotary, anything that blows by the side seals would seem to enter the oil. The side seals are long and present a lot of space to blow by relative to the chamber size. Further, the turbo rotary engines we are considering run pretty rich relative to the average piston engine. Also, I think that turbos exacerbate blow-by on any engine. Some combination of these factors (and/or other factors) would seem to explain the experiences that lead me to conclude that the third gen has (or can have) a lot of blow-by.

I have nothing against running synthetic in a rotary. I have run synthetic oil on occasion in both of the rotary cars I have owned. I did this to see if it would last longer and/or to get the increased performance and protection. My oil turned black quickly, as usual. I run synthetic oil exclusively in my piston engines, transmissions, and differentials. I firmly believe that synthetic offers advantages over conventional oil, but not necessarily in this application when cost is considered.

My engine shows no major wear, deposit, or oiling problems (currently being rebuilt at 92K miles for a non-oil related failure). I regularly run 10W-30 mineral oil (since 72K), and the previous owner ran 10W-30 semi-synthetic (a blend of mineral and synthetic oils). The first 52K miles of my car have an unknown oiling history. For my money, I think that I get better protection out of using mineral oil and changing it every 1000-3000 miles depending on how I use the car. It is always thin, black, and has a gas odor when I change it. I doubt it would be significantly better with synthetic. Thus, extending intervals is probably not a good strategy on this particular engine.

By 'better' in the paragraph above, I mean relative to spending the same amount on synthetic oil, which is admittedly a comparison that is not necessarily a good one. My turbo bearings were certainly worn a lot, but the most significant problem with the turbos was that the housings were cracked. This thread has me thinking more about what kind of oil I should run in my new engine, but I am not yet convinced that synthetic is worth the extra cost in this application. My fear is that I would do less frequent changes with the significantly more expensive synthetic oil. And I think frequent changes are of paramount importance for proper oiling on these cars.

fdbabb

This is from : http://www.usoilcheck.com/fuel_dilution.htm


The presence of fuel in the crankcase reduces oil viscosity and weakens detergency. Excessive amounts of the contaminant can so diminish the oil?s lubrication properties that engine failure will result. Although some fuel dilution is expected, amounts in excess of three percent in two cycle engines and four percent in four cycle engines must be considered abnormal. These levels indicate mechanical problems generating from defects in injectors, fuel pumps, gaskets or seals.

They're talkin pistons of course... Anyway I called them up. They'll send sample bottles to you for free... its $12 for each sample. I asked if there was a volume discount , they said "yeah if it was a 100 samples/year" they could work a deal.

I told them that a bunch of us on the RX7Club forum are thinking about having it done so maybe we could include the words RX7Club.com to get discount.

Anybody wanna volunteer to maintain a spreadsheet? ;-) Miles on engine vs. synthetic vs. mineral vs. fuel dilution vs. solids vs. side seal construction/fit/or clearance to apex seal (how ya gonna measure that?) vs. ????


BTW with ~7000 miles on an aggressive street port rebuild, I'd classify my oil as a "strong" gasoline smell and more like 10 W in viscosity (SWAG). I change mine every 2000 or less and jack up the car to try to drain coolers. Level holds steady.

After a fresh change the gasoline presence is there almost immediately, but doesn't seem to get more diluted ( i would've guessed that over time it would get more and more diluted).

My $.02
Jeff

GoodfellaFD3S

iTrader: (213)

Interesting, but what I expected. Max is in agreement on the side seal problem.

My Dad is changing my oil sometime soon, and I'll have him keep a sample so that I can get it analyzed.