Oil pressure
03-10-10, 04:54 PM
#26
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Thread Starter
Eh, I'm nobody special. Just some guy. Some things I know, some things I don't. Expected oil pressure is one of those things, since I'd never actually had a mechanical gauge before. Heck, my first RX-7 didn't even have an electric gauge, just a low oil light.
If I don't know, I ask, and listen. Then, combined with experience, I know.
I still have no idea what was up with the front cover O-ring. The front cover came off 'violently' (euphemism) and it's entirely possible that it popped out and disappeared.
Do I know it was the front cover O-ring displaced/missing? No, the oil clearance was way out of whack.
Do I know that the oil clearance was the whole problem? No, because I don't know for absolute certain about the front cover situation. Plus, the bearings were like that before...
Do I know that I have it fixed? No. I won't know until after I yank the trans and flywheel, change the rear bearing, throw it all back together, and drive it. Before I see it holding pressure, I might have, I don't know, a clogged oil cooler or something. I did verify that every piece of the oil system that I could see with the front cover and oil pan off was in good condition.
BTW - FC oil pans are the same length as 12A oil pans. Just a useless FYI.
If I don't know, I ask, and listen. Then, combined with experience, I know.
I still have no idea what was up with the front cover O-ring. The front cover came off 'violently' (euphemism) and it's entirely possible that it popped out and disappeared.
Do I know it was the front cover O-ring displaced/missing? No, the oil clearance was way out of whack.
Do I know that the oil clearance was the whole problem? No, because I don't know for absolute certain about the front cover situation. Plus, the bearings were like that before...
Do I know that I have it fixed? No. I won't know until after I yank the trans and flywheel, change the rear bearing, throw it all back together, and drive it. Before I see it holding pressure, I might have, I don't know, a clogged oil cooler or something. I did verify that every piece of the oil system that I could see with the front cover and oil pan off was in good condition.
BTW - FC oil pans are the same length as 12A oil pans. Just a useless FYI.
03-12-10, 11:42 AM
#27
I'd take the feed and return lines and the pressure valve off the oil cooler and throughly clean it out. I've seen excess silicone sealant and all kinds of junk come out with a good cleaning.
Are you using the Teflon o-ring around the rubber o-ring?
03-17-10, 12:31 PM
#28
Old [Sch|F]ool
Thread Starter
I haven't "figured it out" just yet... Might still have low oil pressure. Those bearings had to fail somehow.
I found out the reason why I couldn't disengage the clutch. Pivot ball broke. I guess this is common with an FC trans and ACT clutch. Odd how it broke after I used a block of wood to hold the clutch down for about five minutes while I had the front pulley bolt loose.
I found out the reason why I couldn't disengage the clutch. Pivot ball broke. I guess this is common with an FC trans and ACT clutch. Odd how it broke after I used a block of wood to hold the clutch down for about five minutes while I had the front pulley bolt loose.
03-17-10, 12:54 PM
#30
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I haven't "figured it out" just yet... Might still have low oil pressure. Those bearings had to fail somehow.
I found out the reason why I couldn't disengage the clutch. Pivot ball broke. I guess this is common with an FC trans and ACT clutch. Odd how it broke after I used a block of wood to hold the clutch down for about five minutes while I had the front pulley bolt loose.
I found out the reason why I couldn't disengage the clutch. Pivot ball broke. I guess this is common with an FC trans and ACT clutch. Odd how it broke after I used a block of wood to hold the clutch down for about five minutes while I had the front pulley bolt loose.
03-17-10, 11:00 PM
#31
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Thread Starter
I have the milder one in the car right now.
The car came with the 6-puck solid disc and what I assume is the bad-*** ACT pressure plate. (On a stock port 12A. Umm.... right.) I don't think that clutch ever saw this transmission. I am fairly sure the order was 12A/6-puck/orig. trans - 13B 6-port/6-puck/orig. trans - 12A PP/stock clutch/orig. trans - 13B SP/mild ACT/orig. trans - and only then did the original trans start to leak violently from the front and I swapped the FC trans in.
I may (have to) put the 6 puck disc in but still keep the milder pressure plate. I really hate the "strong" pressure plate because it is designed with a lot of mechanical advantage, which means the clutch engages right off of the floor. It's still a really light pedal, it doesn't NEED that much mechanical advantage. Then again, a lot of the manual transmission cars I drive have high performance Long style pressure plates and you can pull a muscle when trying to shift. None of this wussy Japanese "all controls must be feather light" crap.
50psi at 1200, 90psi at 2500, at room temperature. We'll see what it does when hot later.
The car came with the 6-puck solid disc and what I assume is the bad-*** ACT pressure plate. (On a stock port 12A. Umm.... right.) I don't think that clutch ever saw this transmission. I am fairly sure the order was 12A/6-puck/orig. trans - 13B 6-port/6-puck/orig. trans - 12A PP/stock clutch/orig. trans - 13B SP/mild ACT/orig. trans - and only then did the original trans start to leak violently from the front and I swapped the FC trans in.
I may (have to) put the 6 puck disc in but still keep the milder pressure plate. I really hate the "strong" pressure plate because it is designed with a lot of mechanical advantage, which means the clutch engages right off of the floor. It's still a really light pedal, it doesn't NEED that much mechanical advantage. Then again, a lot of the manual transmission cars I drive have high performance Long style pressure plates and you can pull a muscle when trying to shift. None of this wussy Japanese "all controls must be feather light" crap.
50psi at 1200, 90psi at 2500, at room temperature. We'll see what it does when hot later.
03-18-10, 11:04 AM
#32
Old [Sch|F]ool
Thread Starter
For some reason, with 5 quarts in the FC oil pan, the temp gauge bulb is still not registering anything. That, or my oil temp never gets up to 100 degrees. (Unlikely)
But after 20 minutes of driving.... 15psi at 1500rpm, 40psi at 3000rpm cruise (FB trans again), and 90psi over 4500rpm. So, I'm going to stick the done stamp on this and worry about other things.
edit: I went back to the car after it'd been shut off and the temp gauge was registering 160 degrees. So, the temp bulb is too high up in the oil pan to register with the engine running.
But after 20 minutes of driving.... 15psi at 1500rpm, 40psi at 3000rpm cruise (FB trans again), and 90psi over 4500rpm. So, I'm going to stick the done stamp on this and worry about other things.
edit: I went back to the car after it'd been shut off and the temp gauge was registering 160 degrees. So, the temp bulb is too high up in the oil pan to register with the engine running.
03-18-10, 11:41 AM
#33
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I have the milder one in the car right now.
The car came with the 6-puck solid disc and what I assume is the bad-*** ACT pressure plate. (On a stock port 12A. Umm.... right.) I don't think that clutch ever saw this transmission. I am fairly sure the order was 12A/6-puck/orig. trans - 13B 6-port/6-puck/orig. trans - 12A PP/stock clutch/orig. trans - 13B SP/mild ACT/orig. trans - and only then did the original trans start to leak violently from the front and I swapped the FC trans in.
I may (have to) put the 6 puck disc in but still keep the milder pressure plate. I really hate the "strong" pressure plate because it is designed with a lot of mechanical advantage, which means the clutch engages right off of the floor. It's still a really light pedal, it doesn't NEED that much mechanical advantage. Then again, a lot of the manual transmission cars I drive have high performance Long style pressure plates and you can pull a muscle when trying to shift. None of this wussy Japanese "all controls must be feather light" crap.
50psi at 1200, 90psi at 2500, at room temperature. We'll see what it does when hot later.
The car came with the 6-puck solid disc and what I assume is the bad-*** ACT pressure plate. (On a stock port 12A. Umm.... right.) I don't think that clutch ever saw this transmission. I am fairly sure the order was 12A/6-puck/orig. trans - 13B 6-port/6-puck/orig. trans - 12A PP/stock clutch/orig. trans - 13B SP/mild ACT/orig. trans - and only then did the original trans start to leak violently from the front and I swapped the FC trans in.
I may (have to) put the 6 puck disc in but still keep the milder pressure plate. I really hate the "strong" pressure plate because it is designed with a lot of mechanical advantage, which means the clutch engages right off of the floor. It's still a really light pedal, it doesn't NEED that much mechanical advantage. Then again, a lot of the manual transmission cars I drive have high performance Long style pressure plates and you can pull a muscle when trying to shift. None of this wussy Japanese "all controls must be feather light" crap.
50psi at 1200, 90psi at 2500, at room temperature. We'll see what it does when hot later.
that oil pressure sounds right
with mine i ordered the MFR regulator but it was back ordered, so i took one of the old ones apart, and shimmed the crap out of it. i get like 110 on the stock gauge, close enough
03-18-10, 08:58 PM
#34
Old [Sch|F]ool
Thread Starter
And I think I see why it killed the bearings, too... driving around in town in 5th gear at 15psi oil pressure. Hmm, probably not so good.
I managed to get the engine to ping at about 600rpm while trying to set the idle. I ended up taking a bit over half of the fuel away, for now idle is set at 1200-1500. At it idles at 50kpa?!?!
I managed to get the engine to ping at about 600rpm while trying to set the idle. I ended up taking a bit over half of the fuel away, for now idle is set at 1200-1500. At it idles at 50kpa?!?!
03-19-10, 10:01 AM
#35
Believe it or not but one of the hardest things on your oil is lugging it around at low rpms. As strange as it seems, that is much more stress on them than higher revving at higher loads. To a point of course. I actually do this all the time but with a thicker oil that we run it really isn't a problem. You just ran out of oil flow.
09-23-10, 11:02 PM
#36
Old [Sch|F]ool
Thread Starter
ANCIENT THREAD BUT I HAVE AN UPDATE
Oil pressure had been steadily getting worse. Finally at a rallycross a month or two ago (it's been so long..!) I had maybe 10psi at idle. It would take three or four seconds after startup for oil pressure to come up from zero, too, so I parked the car after only seven runs and jumped into a ZX2 (and found that I forgot how to drive a FWD).
On the way home, about 150mi away from the rallycross site, the engine wouldn't hold any kind of idle when I pulled off for fuel. Ut-oh. When I got home, I found that I'd gone through three quarts of oil on an engine that normally added a quart every 2500 or so from fuel dilution.
What I found on teardown was seriously trashed rotor bearings, a badly scored and blued eccentric shaft, an oil pump that looked like it'd been chewing on gravel, a coating of iron dust everywhere, a handful of flattened (FD) corner seal springs, some seriously worn oil control ring holders (like, the full face was shiny) on the rotor face that had the flat corner springs... and a demolished rear end housing from where the rotor was grinding on it.
It was easier for me to change rotor assemblies than it was to change rotor bearings, so I did that, took every used rotor I had laying around and picked the best oil control ring holders, and bought all new seal springs and Atkins oil O-rings. As well as a new set of side housings, and a GSL-SE eccentric shaft that I'd teardropped the oil holes to promote oil flow to the rotors. And an oil pump that I'd blueprinted. And I ported the oil passages in the front end housing. And I used an RX-8 front cover gasket (it's metal!) to completely eliminate the possibility of the O-ring blowing out, because there ISN'T one.
Current status: 90psi cold idle (~900rpm), 40psi hot idle, 85-95psi at 3000rpm cruise.
YEAH WE GOT PRESSURE NOW
I want to repeat this because it's so awesome: Use an RX-8 front cover gasket. It fits the old engines and SOLVES the cover O-ring problem.
Oil pressure had been steadily getting worse. Finally at a rallycross a month or two ago (it's been so long..!) I had maybe 10psi at idle. It would take three or four seconds after startup for oil pressure to come up from zero, too, so I parked the car after only seven runs and jumped into a ZX2 (and found that I forgot how to drive a FWD).
On the way home, about 150mi away from the rallycross site, the engine wouldn't hold any kind of idle when I pulled off for fuel. Ut-oh. When I got home, I found that I'd gone through three quarts of oil on an engine that normally added a quart every 2500 or so from fuel dilution.
What I found on teardown was seriously trashed rotor bearings, a badly scored and blued eccentric shaft, an oil pump that looked like it'd been chewing on gravel, a coating of iron dust everywhere, a handful of flattened (FD) corner seal springs, some seriously worn oil control ring holders (like, the full face was shiny) on the rotor face that had the flat corner springs... and a demolished rear end housing from where the rotor was grinding on it.
It was easier for me to change rotor assemblies than it was to change rotor bearings, so I did that, took every used rotor I had laying around and picked the best oil control ring holders, and bought all new seal springs and Atkins oil O-rings. As well as a new set of side housings, and a GSL-SE eccentric shaft that I'd teardropped the oil holes to promote oil flow to the rotors. And an oil pump that I'd blueprinted. And I ported the oil passages in the front end housing. And I used an RX-8 front cover gasket (it's metal!) to completely eliminate the possibility of the O-ring blowing out, because there ISN'T one.
Current status: 90psi cold idle (~900rpm), 40psi hot idle, 85-95psi at 3000rpm cruise.
YEAH WE GOT PRESSURE NOW
I want to repeat this because it's so awesome: Use an RX-8 front cover gasket. It fits the old engines and SOLVES the cover O-ring problem.
09-24-10, 06:52 PM
#39
Old [Sch|F]ool
Thread Starter
I break things so other people don't have to.
03-19-11, 03:00 PM
#41
Old [Sch|F]ool
Thread Starter
Okay, I just pulled apart the engine that I built at the end of this thread.
To recap: Series 4 N/A rotors, end housings, and oil pump. S4 T2 center and rotor housings. Early opening street port. Stock seals and springs on the sides, Atkins oil o-rings and apex seals. Series 3 eccentric shaft. Engine went ~400 miles, did a two day rallycross 150 miles away, and lost so much compression that it would not start for the trip home without unplugging the TPS so I could crank it with the throttle wide open. I cranked the idle speed up to 1600rpm (this is a street port, mind you) so it wouldn't stall between runs. By the time I got home the car would barely maintain 60mph, idle speed was about 700 and falling, and the engine died in the parking lot and never restarted.
What I found so far (only have rear rotor apart yet) is another case of flattened corner seal springs and side seal springs. They don't pop up anymore. They move freely, they just don't have any spring tension left. The rear end housing is severely grooved and the center housing is also pretty heavily grooved. Rear rotor bearing shows a little wear. Oil was, in a word, nasty, with black gunk coating everything. Almost as bad as a Diesel engine. And the oil control O-ring holders that measured out at "perfect awesome" are now totally shiny across the faces.
I came upstairs to go to the bathroom and post this... I am taking pictures and I'll probably post another thread. This engine was done up to the nines and it didn't last long at all. And - I hasten to point out - it never lost good oil pressure.
To recap: Series 4 N/A rotors, end housings, and oil pump. S4 T2 center and rotor housings. Early opening street port. Stock seals and springs on the sides, Atkins oil o-rings and apex seals. Series 3 eccentric shaft. Engine went ~400 miles, did a two day rallycross 150 miles away, and lost so much compression that it would not start for the trip home without unplugging the TPS so I could crank it with the throttle wide open. I cranked the idle speed up to 1600rpm (this is a street port, mind you) so it wouldn't stall between runs. By the time I got home the car would barely maintain 60mph, idle speed was about 700 and falling, and the engine died in the parking lot and never restarted.
What I found so far (only have rear rotor apart yet) is another case of flattened corner seal springs and side seal springs. They don't pop up anymore. They move freely, they just don't have any spring tension left. The rear end housing is severely grooved and the center housing is also pretty heavily grooved. Rear rotor bearing shows a little wear. Oil was, in a word, nasty, with black gunk coating everything. Almost as bad as a Diesel engine. And the oil control O-ring holders that measured out at "perfect awesome" are now totally shiny across the faces.
I came upstairs to go to the bathroom and post this... I am taking pictures and I'll probably post another thread. This engine was done up to the nines and it didn't last long at all. And - I hasten to point out - it never lost good oil pressure.
03-19-11, 03:16 PM
#42
That's weird. The only times I've come across similar problems are when the side plates have been resurfaced, which causes oil seals to die (become shiny half way across) very quickly. I've had corner springs go flat from retarded timing/running on trailing only. Also flattened apex springs that way. Severe step wear/grooving of side plates comes from not enough oil metering. These are my experiences. I've never seen all these problems in the same engine before, though. You're unique.
03-19-11, 04:42 PM
#43
Old [Sch|F]ool
Thread Starter
The front rotor isn't as bad, but it looks like all three side housings are unsalvageable. Deep side seal related step wear that WAS NOT there before - I converted the engine from T2 end housings because of step wear. Besides that, I can see a definite "landing zone" for the side seals where they were crossing the aux port. Maybe it's not a problem, but I don't want to risk it given that I have probably three engines' worth of FC N/A side housings. It was an experimental port, anyway, and not really worth it in the long run - go bridge or go home.
E-shaft still looks good.
The rotors, however, have V-shaped apex grooves now. I officially don't have any more 2mm seal rotors, now. One set has trashed bearings and these have trashed grooves, and I don't feel comfortable pressing new bearings into an engine. I've never heard of an OEM bearing spinning but have heard lots of stories of replacement bearings spinning.
Which sucks, because I just bought another set of Atkins apex seals.
The rotor housings don't look as bad as I remembered them. I'm going to try something to clean them up.
The corner springs and side seal springs seem okay on the front rotor.
Hmm... I didn't check the apex springs (which were new). The apexes are all sitting in their grooves with little spring tension, but then again the engine went together that way. The apex seals I used were worn out on the backside, which is what I THOUGHT caused my compression problem before I took the engine apart.
This engine always ran 1:128 synthetic 2-stroke oil on the street and about 1:80 in competition. The rotors are heavily carboned but I attribute this to running extremely rich when compression went away, as I'm using a MAP based fuel system.
E-shaft still looks good.
The rotors, however, have V-shaped apex grooves now. I officially don't have any more 2mm seal rotors, now. One set has trashed bearings and these have trashed grooves, and I don't feel comfortable pressing new bearings into an engine. I've never heard of an OEM bearing spinning but have heard lots of stories of replacement bearings spinning.
Which sucks, because I just bought another set of Atkins apex seals.
The rotor housings don't look as bad as I remembered them. I'm going to try something to clean them up.
The corner springs and side seal springs seem okay on the front rotor.
Hmm... I didn't check the apex springs (which were new). The apexes are all sitting in their grooves with little spring tension, but then again the engine went together that way. The apex seals I used were worn out on the backside, which is what I THOUGHT caused my compression problem before I took the engine apart.
This engine always ran 1:128 synthetic 2-stroke oil on the street and about 1:80 in competition. The rotors are heavily carboned but I attribute this to running extremely rich when compression went away, as I'm using a MAP based fuel system.
07-18-11, 11:58 AM
#45
Old [Sch|F]ool
Thread Starter
No updates. See thread about side housing grooving, which was determined to be due to insufficiently good air filtration.
I'm running a half bridge GSL-SE engine now, which sucks, but it's all I had to put together at the time.
I'm running a half bridge GSL-SE engine now, which sucks, but it's all I had to put together at the time.
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