Notices
Series I Major Horsepower Upgrades This is the place to discuss Super Chargers and Turbos, Nitrous, Porting, etc

slash128's Top Mount Build

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 11-23-2018, 07:45 PM
  #2301  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Originally Posted by madrotor
Slash, what's your exhaust setup from the turbo down please
Thanks
Just downpipe to Agency Power midpipe. Any specifics you are looking for?
Old 11-23-2018, 07:52 PM
  #2302  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
I recently got a "rattle" like Brettus:

https://www.rx8club.com/series-i-maj...0/#post4792932

and an oil leak between the front iron and house so I pulled it out and tore it down. No wear from the E&J seals, all apex seal surfaces have a mirror finish. Looks like I do have some exhaust port wear from the solid corner seals. Haven't found the cause of the rattle yet but the oil chain had excessive slack so I am thinking that might have been it...



























Last edited by slash128; 11-23-2018 at 08:00 PM.
Old 11-24-2018, 12:23 AM
  #2303  
Registered
 
madrotor's Avatar
 
Join Date: Apr 2015
Location: Leicester, UK
Posts: 60
Received 8 Likes on 7 Posts
Sorry you had to pull your engine out Slash
Thanks for replying to my question, I was wondering if its 2.5" or 3" exhaust basically.
Old 11-24-2018, 10:39 AM
  #2304  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Originally Posted by madrotor
Sorry you had to pull your engine out Slash
Thanks for replying to my question, I was wondering if its 2.5" or 3" exhaust basically.
Ah, gotcha. The turbo outlet is 3" but the down pipe ID is 2.75". The mouth of the AP midpipe is 2.5" but then it opens up again. I'd of course prefer 3" or even 2.75" all the way back, but it seems to do the job.

No worries about pulling it out, I have been curious to see what it looked like on the inside after seeing what Brettus found in his awhile back. All part of the Rotary Life
Old 11-24-2018, 10:42 AM
  #2305  
Registered
 
madrotor's Avatar
 
Join Date: Apr 2015
Location: Leicester, UK
Posts: 60
Received 8 Likes on 7 Posts
Thank you very much for the feedback, I am glad it doesn't look scarred or damaged, what's your thoughts on the findings then?
Old 11-24-2018, 11:23 AM
  #2306  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Yeah, I didn't blow this motor for a change, lol. I ran it hard at 17psi for the last 2 years and never had a detonation event that I was aware of, roughly 20K miles. It didn't quite build boost as quick as the remans I ran prior but when it kicked in it was still mean. I have been running W/M injection this time around, along with the E&J RX7 apex seals and solid corners. Wondering if the solid corners were not necessarily a good idea as there seems to be some wear around the exhaust ports. Other than the exhaust port areas the sides and center look great. The rotor housings have no wear marks whatsoever. All apex seals are intact. I am sharing because there have been reports of these seals eating housings but I didn't experience that. The donor motor was a used junk yard pull and I didn't measure all the wear surfaces so I attribute the boost lag to either out of spec parts and/or more likely I probably didn't get things optimal since this was my first rebuild ever, rotary or otherwise.

There were two reasons I pulled it: a rattling noise and an oil leak between the front iron and front housing. The oil leak was at the top of the spark plug side, right where the oil goes through that dowel pin. Both o-rings seemed to be intact and in good shape, not pinched, etc. It didn't leak at first but it developed over time until about two weeks ago I parked at work and it deposited a nice oil pool on the ground. I didn't find any smoking gun inside. I Hylomar'ed the seals but being my first rebuild I probably didn't do it right...

As for the rattle, it had developed after I pulled the motor earlier this summer to replace the clutch bearing. It started very faint a few days after and grew to be very noticeable, however only while in boost. I pulled the car apart several times after that and could never find the culprit. Since the oil leak sprung I needed to pull it out anyway so I figured I'd tear down the motor and have a look. Nothing really... The only thing I found suspect was the oil chain is pretty slack. Perhaps it was slapping around under load. The rattle could have started prior to doing the clutch work and I just didn't notice it. For all I know the rattle could still be something non-motor related, we'll see...

For this round I picked up another reman, the thing looks brand new. The dealer said there were only 26 left in US inventory and they aren't making more. Not sure how accurate that is, but figured I'd snag one while I have the chance. $4275 + tax (plus $1K core) for those interested. Since they are likely going to be gone soon this may be my last reman and I'll have to get some practice doing my own rebuilds, given the way I abuse my car I am contemplating dropping in Goopy RX8 seals on this round, but still thinking about things. Winter has set in here so I have a few months....

Last edited by slash128; 11-24-2018 at 11:31 AM.
Old 11-24-2018, 11:29 AM
  #2307  
Registered
 
madrotor's Avatar
 
Join Date: Apr 2015
Location: Leicester, UK
Posts: 60
Received 8 Likes on 7 Posts
Did you by any chance empty your coolant anytime before that rattle developed?
The reason I am asking is that due to how high our engines rev if you get a tiny bubble or 2 of air in your heater core they seem to cause cavitation under high load and basically it sounds like metal ***** in a can anywhere above 7k rpm or thereabouts.
The following users liked this post:
slash128 (11-30-2018)
Old 11-24-2018, 11:34 AM
  #2308  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
I did when I pulled the motor for the clutch work, but I burped the system when I filled it. And it only happened in boost. I took out the wastegate springs and it never happened, even at redline. I've done coolant fills a few times now so I *think* I did it right, but I can't say for sure so....


Old 11-24-2018, 02:09 PM
  #2309  
Boosted Kiwi
iTrader: (2)
 
Brettus's Avatar
 
Join Date: Apr 2006
Location: Y-cat-o NZ
Posts: 20,523
Received 1,491 Likes on 839 Posts
Originally Posted by slash128
Yeah, I didn't blow this motor for a change, lol. I ran it hard at 17psi for the last 2 years and never had a detonation event that I was aware of, roughly 20K miles. It didn't quite build boost as quick as the remans I ran prior but when it kicked in it was still mean. I have been running W/M injection this time around, along with the E&J RX7 apex seals and solid corners. Wondering if the solid corners were not necessarily a good idea as there seems to be some wear around the exhaust ports. Other than the exhaust port areas the sides and center look great. The rotor housings have no wear marks whatsoever. All apex seals are intact. I am sharing because there have been reports of these seals eating housings but I didn't experience that. ....
I said at the time that I suspected abnormal housing wear was a combination of the soft E&J seals and E50 . As you haven't seen the same wear .... it would seem that is the case ...probably add insufficient lubrication to that mix in my case.
The following users liked this post:
slash128 (11-30-2018)
Old 11-24-2018, 02:36 PM
  #2310  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Yeah, you had some other variables. I was just sharing what I found in my case FWIW.
The following users liked this post:
Brettus (11-24-2018)
Old 11-24-2018, 03:22 PM
  #2311  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Here’s a video of the oil chain slack. I’m no expert but seems loose?

Old 11-27-2018, 10:38 AM
  #2312  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
And the cycle continues,
Old 11-27-2018, 11:00 AM
  #2313  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
You didn't expect otherwise, did you?
Old 11-27-2018, 11:28 AM
  #2314  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
Nope,
Old 11-29-2018, 07:57 AM
  #2315  
Registered
 
strokercharged95gt's Avatar
 
Join Date: Sep 2005
Location: Tampa
Posts: 1,023
Received 200 Likes on 156 Posts
Originally Posted by slash128
Here’s a video of the oil chain slack. I’m no expert but seems loose?

https://youtu.be/jiZERISt-PY
Definitely seems looser than my oil pump chain. I know its has some slack in it. I don't think that would be enough slack to jump a tooth or off completely.
Old 11-30-2018, 01:08 PM
  #2316  
Boosted Kiwi
iTrader: (2)
 
Brettus's Avatar
 
Join Date: Apr 2006
Location: Y-cat-o NZ
Posts: 20,523
Received 1,491 Likes on 839 Posts
Originally Posted by slash128

As for the rattle, it had developed after I pulled the motor earlier this summer to replace the clutch bearing. It started very faint a few days after and grew to be very noticeable, however only while in boost.

...
I had a rattle on one of my earlier engines that had done about 60000kms ....... turned out to be caused by the corner seals dropping into that step beside the exhaust ports.
The oil leak is likely a crack in the front iron beside the dowel pin .
The following users liked this post:
slash128 (11-30-2018)
Old 11-30-2018, 10:09 PM
  #2317  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Originally Posted by Brettus
I had a rattle on one of my earlier engines that had done about 60000kms ....... turned out to be caused by the corner seals dropping into that step beside the exhaust ports.
The oil leak is likely a crack in the front iron beside the dowel pin .
Appreciate the feedback! And I certainly never meant to imply that your findings about seals and housing wear were not valid, I just wanted to share my findings as data points. Others also suspected the E&J apex seals of housing wear. I am not a advocating for or against them, just sharing that I found no housing wear after 20K miles of beating on it at high boost. Take it for what its worth.

I couldn't find any smoking gun for either the rattle or oil leak in my case. There was some wear around the periphery of the exhaust ports, similar to what you posted, which could have been the source of the rattle but I don't have any way to know for sure. This wear could have been due to the solid corner seals, also E&J.

As for the oil leak- I could find no cracks in the iron. But the o-ring that goes around the dowel appeared to be a bit flat, so could have been that.

I am not an experienced engine builder so either or both issues could have been a number of things attributed to my lack of experience. I plan to put some Goopy RX8 seals in this reman I picked up, hopefully I put it back together right I've got enough parts for another rebuild if I blow this one. I am not satisfied to live in the "safe" zone so I will continue to pay to play
The following users liked this post:
RotaryMachineRx (12-10-2018)
Old 11-30-2018, 10:57 PM
  #2318  
Boosted Kiwi
iTrader: (2)
 
Brettus's Avatar
 
Join Date: Apr 2006
Location: Y-cat-o NZ
Posts: 20,523
Received 1,491 Likes on 839 Posts
Originally Posted by slash128

As for the oil leak- I could find no cracks in the iron. But the o-ring that goes around the dowel appeared to be a bit flat, so could have been that.

:
Have a really close look at the thinest part of the cast iron around that dowell hole ...if it were cracked ...that's where the crack would be.
Old 11-30-2018, 11:09 PM
  #2319  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
I looked pretty close at that area but didn’t find any cracks. I could have missed it. Anywho, it’s on its way back to Mazda as the return core on this reman.
Old 12-04-2018, 11:23 AM
  #2320  
Registered
 
Darkning's Avatar
 
Join Date: May 2011
Location: Charlotte, NC
Posts: 121
Received 0 Likes on 0 Posts
Is it possible it was just other inherent RX8 issue like a gunky SSV? It's easy when you dive deep into FI builds to overlook the simple things.
Old 12-04-2018, 08:14 PM
  #2321  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
I'm not ruling anything out. We'll see if the rattle remains with the new motor.
Old 12-21-2018, 01:29 PM
  #2322  
Registered
 
madrotor's Avatar
 
Join Date: Apr 2015
Location: Leicester, UK
Posts: 60
Received 8 Likes on 7 Posts
I fixed my SSV rattle fairly easily, I am sorry I have no pics to show but if you have a look at yours you'll find that on the inside there is a backing plate that the bolts from the front screw into because it's all metal on metal contact some wear is bound to happen, what i did was add a very thin shim that I cut in the shape of this backing plate between the plate and the SSV valve body, I smeared heavy duty moly grease on it to insure a slower wear rate and put everything back together and there is no more rattle and that was nearly 2 years ago, if your engine is out I advise you to do it, I am sure you know pulling the SSV out is a bitch when the engine is in the car.
Old 02-25-2019, 04:07 PM
  #2323  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Hmm, looks like I found the cause for low boost maybe a potential candidate for the elusive rattle as well...





Old 02-25-2019, 04:12 PM
  #2324  
n3rd
Thread Starter
 
slash128's Avatar
 
Join Date: Aug 2009
Location: in my mind
Posts: 2,129
Received 40 Likes on 34 Posts
Fresh remain torn down and Goopy RX8 seals installed. All dressed up and nowhere to go...










Old 02-25-2019, 04:32 PM
  #2325  
Boosted Kiwi
iTrader: (2)
 
Brettus's Avatar
 
Join Date: Apr 2006
Location: Y-cat-o NZ
Posts: 20,523
Received 1,491 Likes on 839 Posts
Is that just a spare one Slash or is the other one gone ?


You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: slash128's Top Mount Build



All times are GMT -5. The time now is 08:16 PM.