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Lets look at expo1's over 100K renesis motor

Old Feb 22, 2008 | 02:08 PM
  #126  
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I have been thinking of coating the exhaust/intake ports. This has helped me go more torward that. corner seals, corner seals, corner seals-what to do.
olddragger
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Old Feb 22, 2008 | 02:13 PM
  #127  
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Originally Posted by olddragger
I have been thinking of coating the exhaust/intake ports. This has helped me go more torward that. corner seals, corner seals, corner seals-what to do.
olddragger
Coating them with what?
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Old Feb 22, 2008 | 02:19 PM
  #128  
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Originally Posted by Charles R. Hill
The groove running the circumference of the housing is from the corner seals. Might it be from low OMP volumes?
Nope. The corner seals never touch the rotor housings. That is from the small triangular section of the 2 piece apex seals. It's where the top point rides on the housing. This damage is very common on all engines running 2 and 3 piece apex seals.
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Old Feb 22, 2008 | 02:36 PM
  #129  
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Originally Posted by tdiddy
Coating them with what?
something sexy & slippery .......
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Old Feb 22, 2008 | 06:07 PM
  #130  
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These rotor housings have that groove on both sides of each housing. The apex corner tip and the other side are scraping the chrome surface away. The apex seals were warped in the middle and have ridges along their sides where they'd been rocking in their grooves. The carbon patch on that housing pic is from the seal skipping over the sparkplug hole.

Paul.
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Old Feb 22, 2008 | 06:27 PM
  #131  
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That first pic, with the cabon filling in part of the exhaust port; is that normal? Looks like it is blocking a significant portion of the port. Or is that part of the port not important since by then most of the exhaust is already gone?

Kinda new to this whole "magic triangle" thing
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Old Feb 22, 2008 | 06:31 PM
  #132  
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Originally Posted by Bester
That first pic, with the cabon filling in part of the exhaust port; is that normal? Looks like it is blocking a significant portion of the port. Or is that part of the port not important since by then most of the exhaust is already gone?

Kinda new to this whole "magic triangle" thing
Not important, just as you noted.

Paul.
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Old Feb 22, 2008 | 07:15 PM
  #133  
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Originally Posted by Bester
That first pic, with the cabon filling in part of the exhaust port; is that normal? Looks like it is blocking a significant portion of the port. Or is that part of the port not important since by then most of the exhaust is already gone?

Kinda new to this whole "magic triangle" thing
I think thats what its for ...
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Old Feb 22, 2008 | 07:44 PM
  #134  
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Originally Posted by Mazmart
The apex seals were warped in the middle and have ridges along their sides where they'd been rocking in their grooves.
Paul.
Paul,
Could this help RG's theory on the center of the seals not receiving proper lubrication?
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Old Feb 23, 2008 | 10:46 AM
  #135  
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coatings via Swan's--look into it. Mainly for heat related issues, not for carbon buildup per say. they even have coating that could go on the inside of the waterjackets to help transfer the heat is a faster way.Recips use it on the inside of their pistons etc.
OD
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Old Feb 23, 2008 | 12:45 PM
  #136  
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Here are some very important ones. They show stationary gear bearing damage. The rotor bearings are alright. Better viscosity would have improved these conditions.

Paul.
Attached Thumbnails Lets look at expo1's over 100K renesis motor-pict0487a.jpg   Lets look at expo1's over 100K renesis motor-pict0488a.jpg   Lets look at expo1's over 100K renesis motor-pict0489a.jpg   Lets look at expo1's over 100K renesis motor-pict0497.jpg   Lets look at expo1's over 100K renesis motor-pict0498.jpg  


Last edited by Mazmart; Feb 23, 2008 at 12:49 PM.
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Old Feb 23, 2008 | 12:48 PM
  #137  
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And one more.

PT.
Attached Thumbnails Lets look at expo1's over 100K renesis motor-pict0503.jpg  
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Old Feb 23, 2008 | 01:18 PM
  #138  
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Originally Posted by Mazmart
The rotor bearings are alright. Better viscosity would have improved these conditions.

Paul.
In your eyes what would have made the wear less on the engine?
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Old Feb 23, 2008 | 02:33 PM
  #139  
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Ouch. Looking at the bearing wear, I'm switching to a higher viscosity on the next oil change.

I have 87k on mine and fought off a power loss issue last year with multiple tanks of Techron. I got my power back, but I bet I’ve got a good amount of carbon build up still. Guess I better start saving up for a Mazmart engine in the next year or two.
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Old Feb 23, 2008 | 09:10 PM
  #140  
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Originally Posted by HiTMaNN
In your eyes what would have made the wear less on the engine?
According to Mr Engman: A thicker viscoscity would have provided a greater cushion countering to some extent the mis-alignment that is somewhat natural in engines. The greater cushion allows the fine particles, that are by-products of combstion, to move along without doing as much polishing away at the babbit as occurred in this case. This is his opinion based upon examining bearings for decades.

My own thoughts on the viscoscity issue is this: The requirements for a 5W oil are not present here in the US at any time in the year. The flow rate test for a 10W are conducted at -30C and therefore more than adequate. The 40 weight side that I recommend is important to behavior of the oil when hot (And especially in hot climates). You want to, again, provide that cushion for the shaft. Let's not forget that several other countries have thicker oil recommendations from Mazda for their RX8s. The engines that we build for race teams (Renesis) don't have bearings looking like this because they're running 20W50.

Why are we being told that we should run 5W20? I would think it facilitates a quicker warm up and helps both fuel economy and horse power numbers ever so slightly. I think we have unique emission requirements here that warrant doing every last thing to enhance both the fuel mileage and power numbers.

Paul.
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Old Feb 23, 2008 | 09:52 PM
  #141  
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^sold.. i'm going 10W40 next oil change.. friggin love this site
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Old Feb 23, 2008 | 10:13 PM
  #142  
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How would a thicker oil (e.g. 10W40) affect the operation of the OMP? I would think that it would reduce it's flow rate. That would be calibrated for a specific weight of oil in the ecu. Your racing engines wouldn't be using the OMP.
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Old Feb 23, 2008 | 11:20 PM
  #143  
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Hmmm well for those that believe in synthetics.. I think the best bet is to go for German Castrol.. a 0W-30 that has been found to be thicker than most 40W oils when up to operating temp, yet is very fluid at cold start ups. It's found at Autozones (they have a very good deal at the moment) I'd switch to it now if I wasn't so paranoid about not breaking-in the engine enough (4K miles now).. decided not to switch to syn. just yet b/c I hear rotaries take a while to break-in
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Old Feb 23, 2008 | 11:32 PM
  #144  
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Why do you want it to be so thick? Have you used thick oil in a Rotary before? Your Rotors are like weights lol
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Old Feb 24, 2008 | 12:20 AM
  #145  
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Originally Posted by DOMINION
Why do you want it to be so thick? Have you used thick oil in a Rotary before? Your Rotors are like weights lol
dont know about the current Renesis but most Japanese oil company prefer heavier oil for Rotaries.

In Japan they're selling 45 weight oil to all 13B engines.
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Old Feb 24, 2008 | 12:22 AM
  #146  
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some true insights from credible sources in this thread. i like that.


i would just like to touch on the OMP seal leakage issue for a sec. was it causing all that extra splash on the engine?
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Old Feb 24, 2008 | 12:26 AM
  #147  
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Originally Posted by alnielsen
How would a thicker oil (e.g. 10W40) affect the operation of the OMP? I would think that it would reduce it's flow rate. That would be calibrated for a specific weight of oil in the ecu. Your racing engines wouldn't be using the OMP.
I think what Paul or Mr. Engman trying to say is that, when you use heavier oil, it reduces the wear on the bearings.

If you look closely to the picture, those bearings looks kinda bad.

as for OMP rate, I wouldnt worry too much, Im sure 5w40 can protect better than 5w20. Plus I premix. so no worry for me.
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Old Feb 24, 2008 | 12:39 AM
  #148  
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Originally Posted by nycgps
dont know about the current Renesis but most Japanese oil company prefer heavier oil for Rotaries.

In Japan they're selling 45 weight oil to all 13B engines.
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Old Feb 24, 2008 | 07:55 AM
  #149  
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Originally Posted by DOMINION
Yep ...
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Old Feb 24, 2008 | 08:51 AM
  #150  
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looks like some coatings/treatment may be appropriate for these bearings also?
OD
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