ASH8

Smart *** POM...

this coming from an Englishman who does not even OWN an RX-8...HOW Dare you!

ASH8

Denny, thought the same, sort off.

Some say Mazda's "sloppy" side seals are moving too much when cold and cutting through the Side Seal Spring (S), Mazda have modified side Seal Springs in 2009, but left the Side Seals as they are.

Yeah, I would like to know more about engine history..

ASH8

Well 5W30 WONT CUT IT...

Seriously, starting Pre-Mixing at 38K is too late, yes I know you got to 100K, But think about it, if the middle of the Apex Seal was wearing unevenly because of the lack of Lube in the middle after 38K, the damage is done (well some), by adding pre-mix it is not going to correct or straighten a slightly concaved Apex Seal is it.

WOW how long did you drive it for, the damage on the rotor/housing is pretty bad.
Must of ran like a piece of crap, starting?, or did it just die on you??..

What are you going to do, buy new parts, strip another engine for parts??
Or have you though of buying a Mazmart engine from Paul??

They do beautiful Rebuilds and at a good price, and are great honorable Vendors you can trust....

WHERE is Paul when you need him??..

Good luck and thanks for the pics..

Brettus

iTrader: (2)

Thems the whitest gloves I've seen for a while ....

SilentSpring

Doc - Yes the car has a cat, and there is nothing solid in there....just fine powder.

Ash - What would you like to know about the history? Oil was changed round about every 3000 miles, coolant every 30,000 or 1 year.

The car was driven about a half mile after it died. It restarted after sitting for about 15 minutes and had to be held at 1500rpm just to stay running.

I'm with you on the seal wear

Thanks

SilentSpring

Had to prepare for my photo shoot

PhillipM

They keep having engine problems, what'd I want one of those for

Besides, I can't afford 7 litres of treacle every time the engine wants servicing

ASH8

I heard molasses is good an cheap in UK, particularly for those glorified "Beach Buggies"

PhillipM

It's not doing too bad for a beach buggy, it's towed 4 people out of hedges/ditches today in the snow already...'specially with this torqueless engine
20w-50 would look like molasses here at the minute anyway, -12*c this morning

Rotary Inspired

iTrader: (1)

subscribing. I have more to add, but it will be later.

olddragger

iTrader: (3)

Hince my statement that others have seen more than me.
I do know I drove for around 100miles on one rotor after breaking an apex seal on the race track and my rotor didnt look ANYTHING like that?
Regardless the plate stuff had to go somewhere and thats where the powder came from?
I wonder if plate failure took out the seal?

Man that looks as bad as my cousins face when he was 14 yrs old.

Ash thanks about the side seal info.
OD

Rotary Inspired

iTrader: (1)

OK here is my take on it.

You had an apex seal fail on the front rotor. The reason it failed I can only speculate over the computer, but history repeats it's self so I have a pretty good idea.

As the apex seal wears it gets smaller, and the rx8 seals are already much smaller new than previous 13B seals. As it wears it is less stable in the apex seal slot at high rpms and begins to chatter. At this point it the seal could have damaged itself during the chatter or actually left the apex seal slot during high rpm use due to the wear. Take your pick neither are good.

This happened more often than you would realize w/ the 89-91 rx7 N/A motors. Before you dismiss this read on. In 89 Mazda raised the redline from7K to 8k, lightened the rotors, increased compression, and changed the intake manifold design. Sound familiar? Now I have seen several of these motors loose an apex seal at 4K and up in the rpm range on stock 3 piece seals as they wear and get over 60K miles. The 3 piece seals will actually loose the top piece as it wears and will flip out of the groove or break.

All the damage you see in your motor is a direct result of the apex seal leaving its home. When it does this in the Renesis it does not have the easy exit through the periphial exhaust ports of the past 13b's. The seal has to try and get to the side exhaust port to escape the motor. Unfortunately this design creates a disaster when the seal fails. Your seal looks to have bounced around on the side of the rotor between it and the front side plate causing the damage to the rotor. The scoring on the side plate came from the damaged rotor and seals running on that plate before shutting the engine off. From there it looks like the seal started to shatter into little bits and traveled around the combustion chamber several times damaging your rotor housing and the faces of your rotor before being crushed enough (your fine dust) to exit the side exhaust ports.

This process above put extra pressure on the front face of the rear rotor cracking the corner seals. I have tried to run a motor on broken or cracked corner seals and the compression is so poor its hard to keep the car running let alone getting it to start.

That's my take on your situation. Hope it helps and good luck w/ the build.

Rotary Inspired

iTrader: (1)

While there is a quite a bit of carbon in the exhaust ports, but its not overwhelmingly more than what I have seen. I would guess that the BHR fuel pump supplies more fuel than the stock pump richening the mixture some, which in turn adds carbon.

Excess fuel is what creates the carbon. The oil injected in the chamber is so small that it really does not have much play in this. You should see the carbon build up on the JDM turbo motors. Quite impressive to say the least.

SilentSpring

Rotary Inspired - Thank you, I won't discount anyone's opinion on what happened as it all will help put the pieces together on what happened.

The apex seal that's missing looks like it broke and bent over into the rotor as there is a depression about a 1/2 inch long. Besides that the front plate has that missing piece and only 1 scratch in between the intake and exhaust ports. The only thing left of that apex seal was the corner piece.

How do you feel the apex seal got in between the side seal and the plate?

What do you think about the side seal springs? Given what you said about the extra forces cracking the corner seals, I am thinking that they might have also destroyed the springs.

Rotary Inspired

iTrader: (1)

The only other way I have seen to accomplish this is w/ boost and lots of it.

The apex seal got between the plate and rotor as it was trying to exit through the exhaust port first time around. It did not succeed in it's endevor and went for a ride getting trapped as the rotor crossed over the exhaust port. Then the rotor carried it up to the intake ports where it got jammed up and took out part of the intake ports. From there it just went round and round throughout the motor til it was small enough to exit stage left.

That's my take on the situation. Good luck.

Brettus

iTrader: (2)

Less than 2% at high rpm in my (turbo) application ....
In normal low load operation ,no difference .

rotarygod

That's definitely not an oil related failure.

9krpmrx8

iTrader: (46)

So basically the bearings look good so using a good synthetic and changing it often seemed to have helped. I just wonder if he had been running the SOHN and premixing since day one would have helped.

rotarygod

I would suspect that lack of lubrication to the center of the apex seals is what ultimately led to the death of this motor. That apex seal died first, and on it's attempt out the exhaust port damaged the side and corner seals.

Mackmazda

here is an option ..http://www.goopyperformance.com/content/corner-seals

DocBeech

iTrader: (1)

who be this member since 2007 with only one post???

paulmasoner

iTrader: (1)

lol that is funny. whats not funny is a website/company charging $75 for a file, feeler gauge, and a SS brush

rotarygod

Goopy? That was the best name available? All I had to see on their site was the claim that their oversized tension bolts were a better alternative to dowel pinning. Um, actually no it's not. Those won't really do anything to strengthen the engine at all as dowel pins are limiting movement in an entirely different plane. I wouldn't use anything from a company that claims that. Keep in mind using studs would be better than using bolts anyways so if you were going to replace the bolts with something stronger, use studs and not larger bolts. That's a waste of time.

PhillipM

*If* the housings can take the extra clamping loads from the larger bolts without distortion, they would do much the same.

But that's a big if....

ganseg

iTrader: (5)

Now I am convinced of synthetic at 3k intervals - except I will go to 3,333 miles so my engine will die at 99,900 miles!

Did you ever have your oil tested? I had rotella 10W30 tested at 3k and it's viscosity was down to5W20. So, I was convinced that wasn't going work.