fdbabb

New owner of 93 R1. Very pleased, so far. Oil smelled of gasoline and is thinned out. Replaced oil. Same result. Will drain oil coolers by jacking up front end of car, and try again. Car sold with ~6K miles on rebuilt engine. Has AST, down pipe, mid pipe, Apexi N1s, Stock ECU. Boost limited to 9 pounds via needle valve assembly. No Smog pump. Greddy underdrive pulleys. Those are only mods I know of. Called rebuilder who said he doesn't have a good reason why oil might be in gas except maybe blow-by. But not convinced because of 9 pound limit.
Looked on Robinette's site, as well as RX7club FAQ and archives but haven't found possible answer yet.
Please point me to the answer.
Thanks,
Jeff

ludeowner

gas smell in oil is normal, just change your oil more often. I change my oil and filter every 2000 miles.

Also when you said you called a rebuilder was it a rotary specific builder? or you average piston rebuilder?

fdbabb

Oops, Also has "aggressive" street port.
Thanks. Thats it.

GoodfellaFD3S

iTrader: (213)

I had this same problem. I had my motor rebuilt by a reputable shop, and for some reason my oil always smelled like gas, and was always very thin. I'd change it, put in Mobil1 15w50, and the next day it was dark, diluted, and smelled like gas.

After putting maybe 15k miles on the motor, I cracked a seal. Long story, it always is. This turned out to be a fortunate occurrence, however.

When I tore the motor down I found that my side seals were loose laterally in their grooves. That is, I could take each side seal and wiggle it back and forth between the corner seals, and there was *way* too much play. My rotor bearings were also trashed, and my eccentric shaft was on the verge of becoming unusable. Did anyone say "improprer tolerances" ?

Rebuilt the motor to Gotham specs, and, lo and behold, my engine oil is nice and clean and doesn't smell of gasoline anymore. Coincidence? You decide......

ludeowner

I wonder if the gas in oil smell is only true of stock motors or stock reman motors, and not of blueprinted or built motors. Or maybe it's just a sign of old engine age.

Scrub

iTrader: (25)

come on now....Rich you should know this too, your not cool unless you have gas in your oil. All the Rx-7's are doing it these days

GoodfellaFD3S

iTrader: (213)

Well, gas in your oil means that 20w50 is more like straight 5 weight. It's a pretty easy way to destroy your motor......

Scrub

iTrader: (25)

I have a smell of gas in my oil, but it's not really that thin. I need to get a compression test once I get back from vacation.

Street King

I have it also. It's not thinning out my oil so much as you guys are saying but it can't be good, lol. Just change your oil more often. Instead of draining your oil coolers unless you really want to cause it's a PITA. Just run your standerd good oil through it after you drained the old stuff. Turn it on and let it idle for a little bit, hmmm 10 mins. Drain the ok oil and put in the good oil of your choice. Yes i know the oil coolers will still hold your ok oil some but it's better than the crap you had in there before the oil change right? Do this about once or twice a year.

fdbabb

The rebuilder is Dave Atkins of Atkins Rotary. Cool guy.
____________________

Yeah, Like GoodfellaFD3S, I'm worried that because its thinned out significantly, that the load bearing capabilities of the oil aren't there when ya need it most.

Got the rear window heavily tinted black (on a Black R1 to begin with) - looks badaaaaaass.

Now if I can just get rid of the black tint in the oil.....

Jeff

turbojeff

iTrader: (30)

I bought my 93 R1 with 36K miles. Oil has always smelled like gas. I doubt the motor was worn out with only 36K. I've sent 4 different samples to Southwest Spectro Chemical for analysis, 10% fuel dilution everytime.

I change the oil every 1500-2000 miles with 20W-50, the car has 62K miles on it now.

All the other FDs and TIIs I've owned also had this smell. It seems completely normal.

Since Rich didn't have his oil tested maybe his was worse with the bad side seals, maybe 20% fuel diluition, I dunno.

DamonB

My engine oil always smells of gas, even with a new rebuild. Only very slightly if the car has been doing street duty, but it reaks if the car has been to the track. For this reason I change my oil every 3000 miles or every 2 track events, whichever comes first. The oil does not look or feel dilluted, but with that much gas in it I am taking no chances.

No matter what type of oil you use it can't do its job well if it's dilluted with gasoline. As fdbabb said, the load bearing capabilities of oil on the bearing journals is diminished if the oil is thin.

Kaotic Dan

My motor was rebuilt 7000 miles ago by Pineapple Racing. I also notice a strong gas smell in the oil, and it turns black really quickly. Also, I was burning alot of oil and just replaced the turbo's and i'm still burning oil. Hmmmmm.

I hope your wrong about the side seals not seating.

Street King

It turns black quickly cause you are also storing old oil in your oil cooler/s.

GoodfellaFD3S

iTrader: (213)

It's not that they didn't seat. Imagine a rotor face. The side seals fit in shallow grooves that run in between the corner seals. Well, I could grasp any one of the 12 side seals with two fingers and move them back and forth......basically, they were too short by maybe 1/16th of an inch on each side.

Also, I have an R1 w/dual oil coolers, and now my oil (as evidenced on my dipstick) is very clean, and has stayed clean even after over 1000 miles of hard driving. Steve builds strong, tight motors, and I'm lucky that he showed me his methodology .

Edit: Also, I'm not trying to imply that Pineapple doesn't build strong motors. I've heard nothing but good things about them. There are a few reasons as to why gas gets into the oil.....

7mania

I have had this gas smell in my oil just recently and I posted it on the forum and have no clear answer and now this thread seems to clarify my problem a bit. Well I never had that strong of a gas smell in my oil before and now my oil is filled with a strong gas smell and it is really thin ever than before. I think I just have to change my oil more often.

wonder1and

A strange thing that happened to me was... I have had this problem for some time now and a I guess about 5 months ago I did a hose job... After I did this my oil didn't get thinned out for I would say 2-3 oil changes... and now its doing it again... damnit.

XSTransAm

I also have gas in oil syndrome... Kinda scary if you ask me... This is the only car ive ever had with that issue... right now im mostly stock with the stock twins... Soon I will be converting to single turbo... I will let you all know if this has any effect on the problem

bploz RX7

I also just recently had a rebuild and after getting back from my 2000 mile road trip I noticed a very strong gas smell every time I checked the oil. Was a little nervous but it seems somewhat common gauging from the responses. I guess running extra rich until I get fully tuned doesn't help either...

mako

iTrader: (5)

i dont think i have ever seen an rx7 that did not smell like some gas in the oil. it also seems the richer the car is running the faster the oil gets dirty and needs to be changed. I don't think its anything people should worry about just change the oil more often.

James

jetmech77

Yea I think most rotary people agree on the 2000 mile or sooner rule.

ZoomZoom

iTrader: (2)

You better get that car straight before you blow that motor. Sotck ECU with those mods and a street ported motor? That thing needs a Stand alone and to be tuned on a dyno with a wideband.

rotary-tt

Perhaps leaking injectors? Common problem with the FC's... anyone pull their injectors and test??

JOES95RX7

Hey everyone. I have the solution or atleast the cause... The only thing that I noticed on my engine during a rebuild was that the oil control o-rings were bad. They were distorted and one was broke in half. The car had the same gas in the oil as the rest of you mentioned and this is what I concluded as my problem. FYI every single rotor seal was perfect and well within mazda specs. The only problem that I have seen is all the rubber o-rings and packings are bad, flattened out or distorted. And a few non-related things like split in the plastic atomizers on my injectors, fuel pulsation dampener leaking, one oil injection check valve a little restrictive. Hope this can be helpful. Has anyone else encountered this in a rebuild too?

fdbabb

bploz RX7 wrote:
I also just recently had a rebuild and after getting back from my 2000 mile road trip I noticed a very strong gas smell every time I checked the oil........

Now there's a couple of nice datapoints. We just got back from running mine down from Portland OR to San Diego. About 1300 miles on the oil I'd say. Let me re-iterate there is gasoline present, not just a typical petroleum product smell. That, and its thin like very light machine oil.

ZoomZoom wrote:
You better get that car straight before you blow that motor. Sotck ECU with those mods and a street ported motor? That thing needs a Stand alone and to be tuned on a dyno with a wideband.

As a matter of fact it goes on the dyno tomorrow 10AM for 2 pulls + Wideband A/F.