i have seen a lot of oil catch cans installed with just a breather on them instead of running a vacuum line back to the engine. I was guilty of that myself. However after "reading up on it" from some reputable sources it is generally felt that supplying vacuum to the sump pan--e shaft area is a good thing to do. Not just because it does a better job of removing deposits/gunk but also a vacuum will help seals to seal.
You can actually install a vacuum line on your exhaust pipe.
OD

 

I need a visual, did you do this already?

 

yes.
OD

 

Pics or it didn't happen.

 

aggghhhhhh--you know my rep!
Paul My engine never looked so good
Kinda hard to let it go. snif
OD

 

Ha ha, but the one in your car now is just as pretty!

Paul.

 

That is a thing of beauty. This will sound wrong but I would love to watch you do it. (rebuild an engine you pervs)

 

The engine looks good. How much does this service cost?

 

believe me-- its a bargain--call Mazmart--they have an 800 number.
OD

 

OK Den,

Let's make sure people are understanding what's going on here and not jumping to normal ultra-quick conclusions that dominant this forum.

Please share as much data you can on your fuel starvation event. Very few people know what this means let alone what it does to a rotary. I fear everyone is thinking this is an oil related issue and/or premix and/or other.

A lean combustion event needs explained and needs supporting data so those reading this thread can understand most is most likely the single triggering event for your engine failure.

Might you have:

-Fuel Pressure data just before, during and slightly after this event? If so, can you share
-EGT (Exhaust gas temps) data. This would be HUGGGE. Hope you recorded it.
-A/F (air fuel) data and where it's measured. I don't know how you power adder guys measure it
-ECM correction factors?

Paul--------nice work documenting with pictures.

To all-----please be careful not to read a few of these posts, come to a conclusion and hold your newly found logic as gospel only to perpetuate these beliefs to others on this forum. Shame on you if you do as you're misleading others (people who were once like you) and decreasing the true value that this forum can provide.

Each of you should be asking "WHY' did this or that happen. "WHY?"is the secret to discovering the root cause.

Now----Den---where's the data my friend. Let's help everyone understand what happened here prior to these engine pics.

 

Sure, now you tell me, after I recently installed one with a breather filter.

 

The old man (Engman) is not a fan of anyone (Including his dark skinned son ) looking on. I have to sneak in the engine room at all the opportunities that I can find in order to take pictures in stages. Some people have done rebuild vids but I'm not convinced it's a good thing for the community (Pros and cons exist). There are elements that can NEVER be illustrated on film and many may believe that they should attempt their own build. This of course is not the same as watching a cooking video although there are many similarities. The main difference would be how technical an operation this is and the extent of the consequences when someone does not know how to examine rotor grooves and how to measure rotor housing thickness and how to repair some things that can mostly only be felt rather than seen. Many builders cannot and should not be installing rotor bearings. There is more than meets the eye in all of this. The reason I said all of this is that part of what's wrong in the rotary world relates to people who shouldn't build building and people who shouldn't tune tuning. The end result is a more tarnished reputation than should be.

This may not have been your angle at all and I myself would like to see Rick from start to finish. He usually takes close to a week from initial exterior cleaning of a core unit and draining of fluids. He methodically cleans everything that he removes from the engine before moving on to other items, thereby setting the stage for reassembly. When it's all apart and he has everything cleaned he begins further examination of parts giving a stronger better picture of the cause of failure (To add to his observations during the take apart process). He begins his list of parts needed. He measures flat housings for flatness and machines them when necessary. After other machining processes like bearing pressing etc all parts are put in specific places for reassembly. The prepped front flat housing is mounted to the stand while prepped rotors watch on eagerly ( I try not to be envious), waiting their turn. It's almost like Santa Claus in his toy making fatory . This is the general process.

Paul.

 

Prices start at $2700.

Paul.

 

I kick myself everyday for not jumping on the $1900.00 deal. Even though I have a new motor I could have a Mazmart motor waiting in the wings! Stupid me.

 

question on this though having vacuum maybe good but the 2007(?) + had the oil routed to the lim, and at some conditions it would then be pressurized wouldn't it ? could that then be a issue ? a check valve would fix that i guess

 

Eric---thanks for coming in.
My lean condition was a fluke. The weird stuff seems to happen to me. I have a thread around here somewhere about it.
What happened was the gasline that supplys the 2 upper fuel injectors (the secondaries)from the main rail had a failed connector. That connector has a "spacer" (its that small red part) that can wiggle out under certain circumstances. This is why Mazda recommends that once you take that gasline off do not put the same one back on. Get a new one. The connector that attaches to the main rail was the one that failed.
It came out while i was on the back straight at RA . I was almost to the little hill crest after T-7 no warning, no change in a/f's (dont have fp info) etc. It just suddenly developed a dead skip. Then I saw lean a/f's! I pitted out--duh ( silver eight was with me) ,parked, lifted the hood and freestanding gas had the space between the lim and engine block filled to the brim. It was actually steaming. Close call. After throwing a few things and talking in such a way my mother would not own me, i got to work and found out what happened.
I did drove it a 100 miles home on one rotor pulling about 150-170 grams per sec on my maf!
You live--you learn.
Paul to my rescue with a new engine.
\I bought a new line and since 3 others have had this problem(one burned completly up!) we now have secured these connectors with ties, small clamps or even velcro. Its the spacer not the pop off fitting that is the problem and the only place in the system that has these are on that line. If that line is ever pulled--buy a new one and then secure it.

You are right Paul my new engine is just as or even prettier!
On the vacuum to the oil catch can---just do it! and be sure to use a proper catch can that filters the vapors well.

 

OD do you have a picture of how you zip tied it?

 

Just by way of further discussion, MazdaManiac post extract circa Feb 2008:

If you just do a vented can (like most people), you are just ventilating the "crankcase", which isn't under vacuum to begin with.

Because of the way the Renesis ventilates, you don't need anything more. You just want to catch the oily water vapor that boils out of the pan.

https://www.rx8club.com/showthread.p...ight=oil+catch

 

From a responsibility standpoint, crankcase vapors are very nasty stuff to be throwing into the air. That's why re-burn of crankcase blowby vapors was one of the very first pollution control measures, back in the '60s.

 

very true about the vapors. Tired of smelling "oil" so much.
No engine crankcase (much smaller in the rotary but it is there) is under vacuum by itself. How ever the crankcase does received blow by, it receives moisture (white milky stuff on dipstick for example) and other contaminents. If you do not place a vacuum to your oil catch then in essence you have removed the oem ventilation system.
Now since the crankcase is not under vacuum---is it under pressure? Or is it at atmosphere pressure? If it is at atmoshere pressure how will anything get out? Heat? IMHO thats not enough. Is it under pressure? You bet your sweet butt it is. How is it under pressure since nothing in there is really a pump (other than the oil pump)? Mabe some oil pump cavatation? Hope not that much! Is it blowby? Bingo! And I have seen unadequete vented engines blow the oil pan gasket, or the dipstick out. I have seen the RX8 blow so much oil back through the intake tube that smoke was coming out of the hood.
Ok so stuff needs to get out of the crankcase. Whats the best way?
You want to do everything you can to keep carbon from forming and sludge from developing. A vacuum assisted oil catch can is one thing you can do.

Ask ls1 engine owners that were noticing they were only getting 50K miles out of there rebuilds when then only had a breather can. Once vacuum was added--got many more miles--75-100K --no lie.
Besides all it is --is one vacuum line. What the heck?
Now if I am wrong or if I am missing something--please let me know cause I sure am not perfect--even though I am pretty.
olddragger

 

I nowhere your coming from I just enjoy watching a master at work. I agree with you just because someone makes it look easy people think they can do it. Maybe that explains why I can't play golf like tiger no matter how much i watch him play.

 

Damn right
So my question is when this older master moves on who will take over? you?

 

It's a lot of HARD work. Tons of cleaning, tons of machining. I've built a dozen engines myself including an FD engine that ran 600 plus hp. I've had people ask me recently the same question. I don't know.

The old man's knowledge and experience are extreme to say the least. I've heard some top builders say that Rick has forgotten more than they'll ever know.

Paul.

 

Mr E will never move on.
OD

 

I would give up my career to build engines all day. Seriously. I was a mechanic in my past life.