captdistraction
GrumpyRacer
Long story short, I just put a motor in the racecar that was used, but I installed a new boundary oil pump gear set and new oil pan (same moroso model I've used with great success on other motors).
While the motor runs well, I'm certain I have an oil pressure issue. I've got 3 different "sensing" locations in the setup: an oil pressure switch on an accusump, a resistive oil pressure gauge that reads on the dash, and a transducer-based sensor that feeds my race-capture telemetry system and has a digital multistage warning light.
Anyways, at idle, the lights all are in warning states (and telemetry shows not much oil pressure or any, for that matter). If I blip the throttle, I get 25 PSI, can hear the accusump audibly fill with oil, but if I let it idle I hear the accusump discharge and then get the warning lights. Running it on a race course made 85-90 PSI which is great. There's one last issue (that may shed some light) in that on track under heavy G load the oil pressure dropped significantly (as low as .4PSI on track per my telemetry).
A previous event:
The current setup (note just shows pressure, map is off):
There are a number of contributing factors that can be in play:
Incompetent Mechanic: I did assemble this, I could have made a mistake somewhere along the line. I did take the front primary tensioners off, the oil pickup tube, oil pump and oil pump gears apart and back together. Additionally I installed an oil pan (the said moroso pan), gaskets, oil cooling loop, sensors, etc.
Oil Cooling Loop: I had a setrab 925 cooler core plumbed in with -10AN lines and an accusump system. There's a number of lines, fittings (and one way check valve). That does cost some pressure drop.
Operating Temperatures: during the race, I did see oil temperatures above 300*. Not bueno by any means. I'm not sure how much higher than 300 as that's where the gauge tops out. Water temps reached 230*. Cooling capacity is being improved for going forward. Ambients were 80* near seal level and low relative humidity. However, the oil pressure was low even when cold
G-Forces: On track, some drops definitely came from decel and high G events (lower RPM as well). In the past the motors never dropped so much, however, maybe 20-30 PSI on a rare event but still well over 50. The accusump responds a bit slowly as well (length of hose probably too long)
Motor condition: Not really a lot of stock in this one as the motor made great oil pressure before being put in my hands. That said it had sat for some time and I had used some unusual tricks to try and prime it with oil. I wonder if I did unusual wear during start up as the lifters definitely took longer than I'd have liked to refill with oil (tapping noises persisted the first 30 seconds of run time). However, I didn't notice it burning oil but only have one event (2 races, 1 warmup, 2 qualify sessions I kept fairly short) on it.
So I'm curious where to start looking for the issue. My next steps are to put the better cooler in place, shorten some lines but some of the things I can try:
Thoughts? I need to make this motor last this season and I know with pressure running like this the motor won't survive forever.
While the motor runs well, I'm certain I have an oil pressure issue. I've got 3 different "sensing" locations in the setup: an oil pressure switch on an accusump, a resistive oil pressure gauge that reads on the dash, and a transducer-based sensor that feeds my race-capture telemetry system and has a digital multistage warning light.
Anyways, at idle, the lights all are in warning states (and telemetry shows not much oil pressure or any, for that matter). If I blip the throttle, I get 25 PSI, can hear the accusump audibly fill with oil, but if I let it idle I hear the accusump discharge and then get the warning lights. Running it on a race course made 85-90 PSI which is great. There's one last issue (that may shed some light) in that on track under heavy G load the oil pressure dropped significantly (as low as .4PSI on track per my telemetry).
A previous event:
The current setup (note just shows pressure, map is off):
There are a number of contributing factors that can be in play:
Incompetent Mechanic: I did assemble this, I could have made a mistake somewhere along the line. I did take the front primary tensioners off, the oil pickup tube, oil pump and oil pump gears apart and back together. Additionally I installed an oil pan (the said moroso pan), gaskets, oil cooling loop, sensors, etc.
Oil Cooling Loop: I had a setrab 925 cooler core plumbed in with -10AN lines and an accusump system. There's a number of lines, fittings (and one way check valve). That does cost some pressure drop.
Operating Temperatures: during the race, I did see oil temperatures above 300*. Not bueno by any means. I'm not sure how much higher than 300 as that's where the gauge tops out. Water temps reached 230*. Cooling capacity is being improved for going forward. Ambients were 80* near seal level and low relative humidity. However, the oil pressure was low even when cold
G-Forces: On track, some drops definitely came from decel and high G events (lower RPM as well). In the past the motors never dropped so much, however, maybe 20-30 PSI on a rare event but still well over 50. The accusump responds a bit slowly as well (length of hose probably too long)
Motor condition: Not really a lot of stock in this one as the motor made great oil pressure before being put in my hands. That said it had sat for some time and I had used some unusual tricks to try and prime it with oil. I wonder if I did unusual wear during start up as the lifters definitely took longer than I'd have liked to refill with oil (tapping noises persisted the first 30 seconds of run time). However, I didn't notice it burning oil but only have one event (2 races, 1 warmup, 2 qualify sessions I kept fairly short) on it.
So I'm curious where to start looking for the issue. My next steps are to put the better cooler in place, shorten some lines but some of the things I can try:
- Bypass the cooling loop and see if pressure improves
- Install the revised oiling loop
- Pull the K-member and look in the pan, check for clearances on the rods
- Check the pan's trap doors
- Pull the timing covers, check a cam cap
- Pull the oil pump out, try a different one
- Check pump pickup clearance to the pan floor
- Try thicker oil (I run synthetic 5w50)
Thoughts? I need to make this motor last this season and I know with pressure running like this the motor won't survive forever.