Possible New Renesis Engine Failure Theory?
Nope. The S1 oil metering system was inadequate causing mixed results, power levels, mileage figures, and reliability between engines. The oil coolers have no fans so don't get any cooling while the car is not in motion or is moving slowly. The engine bay is cramped which doesn't allow air to easily get out. This leads to the engine running hotter. I'll remember a couple of other things but the point is that all of the issues with that motor are known and no new theories are needed.
4 second gens and a first gen. One of the second gens was near 400 hp street ported and beat on pretty hard. Blew up 4 clutches and a few transmission synchros in that one. Engine lived. The first gen was a street port. No problems with the motor in it either. I've had ceramic from at least 2 spark plugs break off and fall into the motors. No problems. I've run one of them out of oil when an oil cooler line broke. Fixed the line and the engine kept running. I've overheated them. No problems. I've even gone with no oil changes only adding it when the oil metering caused it to get low. No problems. I've run everything from 20W50 to 0W20 oil, obviously synthetics and conventional. No problems. It's not to say that with the way I've treated engines that none of those motor didn't have any wear inside but none of them failed. I have never had a broken seal or a bad water or oil ring. All of those cars had over 100K on them with one of them topping 200K. I drive all of my cars hard. I don't believe in babying them. I bought them all used from owners who probably didn't take perfect care of them and I drove them like they should be.
Those cars had mechanical fans which pulled more air than the electric fans. The radiators were larger and the engines made less power, except for the turbo car. The oil cooler was in front of the radiator and always had air being drawn through it. The engine bay wasn't cramped and there was room for air to move and escape. As a result everything was easy to keep cool and there was cooling capacity to spare. Many people put very high powered engines in those cars with no issues. Those engines also had oil metering done in the center of each rotor housing as well as in the primary intake ports. No oil metering lubrication issues.
The third gen had a small engine bay much like the RX-8's that was cramped where air couldn't get out. They had oil coolers without fans. They had an inadequate radiator. Those engines made more power which produced more heat. The turbos were small and restrictive which didn't help things. Mazda changed the water o-rings and unfortunately they failed easily. Rebuilds used the old o-rings for reliability and added a metal heat shield for them. Those cars could overheat sitting in traffic! It's ecu was MAP based so when people increased flow through the motor it didn't take long for things to go bad. Those cars got a bad rep as a result of the way it was designed and because of owners not tuning them. Sadly Mazda didn't learn too much with the RX-8. They fixed a couple of mistakes but made a few more.
There are 2 things required to keep a rotary alive. It's got to be well cooled and it has to be well lubricated through the oil metering. They are amazingly tough if you can do those things.
Those cars had mechanical fans which pulled more air than the electric fans. The radiators were larger and the engines made less power, except for the turbo car. The oil cooler was in front of the radiator and always had air being drawn through it. The engine bay wasn't cramped and there was room for air to move and escape. As a result everything was easy to keep cool and there was cooling capacity to spare. Many people put very high powered engines in those cars with no issues. Those engines also had oil metering done in the center of each rotor housing as well as in the primary intake ports. No oil metering lubrication issues.
The third gen had a small engine bay much like the RX-8's that was cramped where air couldn't get out. They had oil coolers without fans. They had an inadequate radiator. Those engines made more power which produced more heat. The turbos were small and restrictive which didn't help things. Mazda changed the water o-rings and unfortunately they failed easily. Rebuilds used the old o-rings for reliability and added a metal heat shield for them. Those cars could overheat sitting in traffic! It's ecu was MAP based so when people increased flow through the motor it didn't take long for things to go bad. Those cars got a bad rep as a result of the way it was designed and because of owners not tuning them. Sadly Mazda didn't learn too much with the RX-8. They fixed a couple of mistakes but made a few more.
There are 2 things required to keep a rotary alive. It's got to be well cooled and it has to be well lubricated through the oil metering. They are amazingly tough if you can do those things.
If you have an S1 RX-8, even a sohn adapter doesn't fix the problem with the oil metering. Only an S2 engine does that. Pre-mixing addresses the issue better but it comes with it's own downsides as well. Cooling (water and oil) is something everyone can address though.
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-clean-your-omp-mop-injectors-225253/
Cleaned my OMP/MOP injectors. Here is a DIY for it.
https://www.rx8club.com/showthread.php?t=225253
Cleaned my OMP/MOP injectors. Here is a DIY for it.
https://www.rx8club.com/showthread.php?t=225253
Good to see that you are still around!
Can you elaborate?
thanks
thanks
Yeah I'm still here. I've always been here. I just don't post much anymore. I'm more of a tech person and I think I've pretty much run the course on those topics so I haven't really had much to post. I got a bit burned out on cars for a while too. I'm still a mod here though so I've got to clean things up here and there.
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So perhaps the Sohn adapter plus premixing 6-8 oz per tank may be the best solution for S1... eventually together with an increased MOP rate compared to stock.
Nice to see you posting again RG not to many I trust here on rotor topic including me. I consider myself like Sergeant Schultz from Hogans Heros's "I know nothing" that's why I keep my ear to the ground and wait for some good ol' info from the few I trust around here.
Many talents? I'm back to driving a bone stock '90 n/a FC (when I'm not driving a Camry)! I do have a bunch of goodies lying around though. I might have a Vortech V5G sitting around here somewhere.
If you have an S1 RX-8, even a sohn adapter doesn't fix the problem with the oil metering. Only an S2 engine does that. Pre-mixing addresses the issue better but it comes with it's own downsides as well. Cooling (water and oil) is something everyone can address though.
It doesn't affect your octane enough to matter but it may cause problems with fuel filters clogging. It never seemed to be a problem on the RX-7's but RX-8 owners have reported potential problems.



No, RX-8's.
WELL...I think you are and have engineering skill, and talent.