I learnt a valuable lesson very recently. That is you do not mess with your PCV system I replaced the lines with non-standard ones and added a 90° elbow to join 2 lines together this massively increased crankcase vacuum causing oil to be pulled directly out of the sump it was wild.
My '04 Forester XT developed rod knock after 230,000 miles. I wasn't even sure it was rod knock at first, because it did not knock at all while idling, and I still had great oil pressure. It would only start knocking around 1800 RPM and then go away above like 2800 RPM. I stopped driving it almost immediately when it happened. I drove 1 more mile, slowly, to get home and parked it. Finally pulled the engine and sure enough, cylinder #3 rod bearings were trashed. Even with such a short amount of engine runtime after hearing the first sign of rod knock, there was A LOT of metal shavings (not just tiny glittery dust particles) in the oil pan!
I did a 200kmh pull with my STI, when I was done and just going normal speed at low rpm I thought it didn't sound quite right, someone that doesn't know the car would not have known. I got home 5-10km further and it was getting slightly worse but wasn't sure still. The next morning I went to investigate and it was very clear it was that.
Having gone through this twice in the last year, I feel like the coolant temp has a big effect on the oil temp. The first time I blew it(ej20 in a 2005 WRX wagon) outside of Vegas. Blasted 2 trucks on US 93 and 2-3 minutes later let up to slow down to pass another truck and it was knocking. Looked down and the temp was around 3/4. Turned the heater on and fan to full, temp dropped back to normal. After I got it back from the “shop” in Vegas, a coolant line came off. Steam billowing. Once again temp at the same spot. Right after that towed it to SurgeLine and they said all the coolant lines and all the oil seals leak. Oil all over the timing belt(dippy tossed the timing cover) and the accessory drive belts. And now rod knock again. Pretty sure the second time was 100% the oil heated in the oil cooler. As the coolant left the system it got hot and the oil was cooling the engine. The first time I lost 1 qt of oil the second I lost 2 qts. Weird thing was the only thing in the catch can was dust. So I think the oil got so thing it just passed out the seals. It doesn’t leak anymore. The oil pressure light didn’t come on either time. Side not the “shop” in vegas blew it up at least 1 more time maybe twice. And I have the analysis report from black stone saying there was a large amount of bearing material in the oil and it may be need another rebuild. Well now it knocks pretty good, we’ll not good but you know.
One of the most important topics to cover with a Subaru. Definite with a performance based one. One thing is not sure if its been done but the stock oil pressure light switch, if you could upgrade that to a higher setting before its too late.
Depending on factors, with a stock 10mm oil pump your oil pressure at warm idle is barely more than 16psi, so a higher-pressure switch to trigger the oil pressure light on the dash would be "on" at idle a lot more. A proper oil pressure gauge (with a low-pressure alarm you can set) would be much better.
nice video and really useful information, I never though detonation can case bearing failure, so that is why a good tune is so important both for the piston and bearing. good to know!
I love the comments about Subaru and the rod bearings and failures when in all reality it’s the factory rod bolts if you take stock sti rods. Put arp2000 rod bolts and then obviously hone and resize cuz it changes clearances, but every rod bearing failure I have had except the pickup tube failure was a factory rod bolt that has broken, stretched, or fretted from high torque runs. Once I fixed the rod bolts problem my issues went to broken ringlands. So now with my set up 100mm bore stock sti forged rods and 400ft lbs of torque I have had much more success, my Subaru runs and I’m proud to say IV blown up 22 Subaru motors and continuing, and they sit around 375-450 hp for 50-60 thousand miles on stock block ej257 they are tough engines, and if you don’t get greedy with horsepower numbers then you can have a very reliable car.
And if you have a rod failure it is mandatory you clean every part and flush every oil galley oil pan, cam gears in avcs and after first start run for 5 mins and change oil. Then repeat process, untill oil is clean. Do break in in driveway, oil cooler is impossible to clean has to be replaced IV tried, it’s pre filter so it doesn’t go to the rods but it does go through the oil pump. It can also plug up and cause your pump to be stuck in bypass and cavitate I do 3-4 oil changes in 100 miles after a spun bearing rebuild. Cleaned everything and have had really good luck. I think the factory oil cooler/warmer is part of the problem as well. Keeping oil temps at bay also help. How many subarus have spun a bearing but not realized their oil temp is at 260 degrees. This is also what bites people in the butt. Oil pressure gauges and temperature gauges are a must
Hey guys I would love to hear you talk about keeping the torque curve to the left of the chart. And moving the torque curve left if you feel it’s too far right. I have an oem turbo 2.5 wrx and would love to figure out how to get more bottom end
That is a good question. We have discussed it somewhat here: th-cam.com/video/c-ZfPk75Tjg/w-d-xo.htmlsi=HQvky9oRLyvV_0qF But this is always a good topic. I'll add it to the list.
Port your turbo, headers exhaust down pipe. And tune and you will increase spool. Also port waste gate so you can carry top end power. Also 4.44 gear swap to a 2006 wrx jdm tranny. That will make a torque monster
Great topic guys, I think the 6 qt oil pan from KillerB is a good improvement for a modified EJ as it increases likelihood that oil is available for the pickup tube and pump. Also an extra quart keeps the oil a little fresher during that 3000 mile interval. Quick question: Do you think an oem STI oil cooler added to the EJ255 will lower oil pressure with the stock 10mm oil pump? Thanks!
Great question. We like the Innovate Oil Temp and Pressure dual gauge: www.flatironstuning.com/innovate-mtx-d-dual-gauge-oil-pressure-temperature A big reason is that you can get both of those important pieces of information from a single gauge. We have been putting them in place of the factory "sensor". It works well, but the reading can move around a lot, so a damper can be a good idea as well. Hope that helps and Stay Tuned!
I use the AEM (150PSI max) "X Series" oil pressure gauge and am pretty happy with it. Visual "bar graph", large numerical readout and programmable alarm.
@@FlatironsTuning thanks for the information! This is super helpful for my new build. What does the damper look like? And would it got in the oem sensor location first take like a flow meter resistor?
@@Nightdeath4223 Here is a link to the Prosport kit: www.flatironstuning.com/prosport-remote-oil-pressure-sender-installation-kit Basically it just puts the sensor further away from the block, so the pulses of pressure are smoothed out a bit.
Thanks for the question. Something like the Fluid Damper can be helpful on higher power cars, or cars that are revving higher. I wouldn't say it would extend bearing life though. If you want to keep vibration down, doing something like a dynamic balance of the rotating assembly would be the ideal way to do that. Thanks for watching and Stay Tuned!
I have my car in the shop right now I thought is had rod knock sounded bad but they open my oil pan and found no metal shaving in there so they are looking into it more ? What else can it be
About stock subaru oil pressure sensor - don't you guys replace it with, say, mitsubishi sensor? it has 1bar pressure threshold... so the light becomes more informative then "your engine is dead"?
Thanks for the question. The Subaru light comes on around 16 psi which is higher than 1 Bar. I'd say rather than simply replacing it with a sensor that triggers at a single pressure, replacing it with a gauge that actually shows you what is happening in the engine is more ideal. And if you can data-log that pressure, that is way better. Thanks for watching and Stay Tuned!
Upgrading the oiling system is more to do with mitigating the effects of G forces on the boxer engine than power level. If you are taking a long, high G turn with the stock setup, you are cruising for a bruising imo.
@@johnwesely I guess what I want to know is what are the limits of lateral G force for stock oil pan and is there any data for the iag and killer b setups for how much g force they can take, as well as any flaws in those aftermarket designs vs stock oiling system. Thanks
I've been taught from a young age to change my oil every 3 thousand miles and always fix your oil leaks, I'm 56 and have never blown an engine. also killer B told me to use 6 quarts of oil in my ej255, can you confirm that john? with killer B pan
Thanks for your question. There can certainly be errors that are thrown that are related to AVCS cam gears, and in those cases, it can be part of the diagnosis to change them. I would generally say that you would want to take a look at oil pressure before simply changing out the gears, but it is possible that they could develop an issue over time. Hope that helps and Stay Tuned!
0:45 What is bearing failure
1:15 Bearing definition
3:44 What is spun & knock
7:02 Main vs rod & oil path
8:42 Symptoms & analysis
11:36 Bearing deformation
13:40 Not waiting & why
16:54 Reusing & cleaning
20:10 Oil sensors & gauges
22:30 Oil level & g-forces
28:20 Crankcase ventilation
29:18 Oil consumption
30:51 Pans, pickups, baffles
32:51 AOS & catch cans
33:35 Oil pumps
35:08 Oil temperature
Thank you for covering what's probably the most important topic affecting these engines.
Absolutely! Thanks for the question Mike!
Stay Tuned!
I learnt a valuable lesson very recently. That is you do not mess with your PCV system I replaced the lines with non-standard ones and added a 90° elbow to join 2 lines together this massively increased crankcase vacuum causing oil to be pulled directly out of the sump it was wild.
Great discussion, I've learned so much from your videos/podcasts.
Thanks very much and we really appreciate that! Glad that the videos have been helpful.
Thanks for watching and Stay Tuned!
I really appreciate these detailed technical videos. Thanks yall.!
Thanks very much. Really appreciate that.
Glad that you like the tech videos and Stay Tuned!
Dylan needs a raise
Thanks for watching and thanks for the comment. I'll pass that along.
Stay Tuned Sawyer!
My '04 Forester XT developed rod knock after 230,000 miles. I wasn't even sure it was rod knock at first, because it did not knock at all while idling, and I still had great oil pressure. It would only start knocking around 1800 RPM and then go away above like 2800 RPM. I stopped driving it almost immediately when it happened. I drove 1 more mile, slowly, to get home and parked it. Finally pulled the engine and sure enough, cylinder #3 rod bearings were trashed. Even with such a short amount of engine runtime after hearing the first sign of rod knock, there was A LOT of metal shavings (not just tiny glittery dust particles) in the oil pan!
I did a 200kmh pull with my STI, when I was done and just going normal speed at low rpm I thought it didn't sound quite right, someone that doesn't know the car would not have known. I got home 5-10km further and it was getting slightly worse but wasn't sure still.
The next morning I went to investigate and it was very clear it was that.
Having gone through this twice in the last year, I feel like the coolant temp has a big effect on the oil temp. The first time I blew it(ej20 in a 2005 WRX wagon) outside of Vegas. Blasted 2 trucks on US 93 and 2-3 minutes later let up to slow down to pass another truck and it was knocking. Looked down and the temp was around 3/4. Turned the heater on and fan to full, temp dropped back to normal. After I got it back from the “shop” in Vegas, a coolant line came off. Steam billowing. Once again temp at the same spot. Right after that towed it to SurgeLine and they said all the coolant lines and all the oil seals leak. Oil all over the timing belt(dippy tossed the timing cover) and the accessory drive belts. And now rod knock again. Pretty sure the second time was 100% the oil heated in the oil cooler. As the coolant left the system it got hot and the oil was cooling the engine.
The first time I lost 1 qt of oil the second I lost 2 qts. Weird thing was the only thing in the catch can was dust. So I think the oil got so thing it just passed out the seals. It doesn’t leak anymore. The oil pressure light didn’t come on either time.
Side not the “shop” in vegas blew it up at least 1 more time maybe twice. And I have the analysis report from black stone saying there was a large amount of bearing material in the oil and it may be need another rebuild. Well now it knocks pretty good, we’ll not good but you know.
One of the most important topics to cover with a Subaru. Definite with a performance based one. One thing is not sure if its been done but the stock oil pressure light switch, if you could upgrade that to a higher setting before its too late.
Depending on factors, with a stock 10mm oil pump your oil pressure at warm idle is barely more than 16psi, so a higher-pressure switch to trigger the oil pressure light on the dash would be "on" at idle a lot more.
A proper oil pressure gauge (with a low-pressure alarm you can set) would be much better.
nice video and really useful information, I never though detonation can case bearing failure, so that is why a good tune is so important both for the piston and bearing. good to know!
Those KING XPG bearings are what I run in my WRX. Seem great so far 😎👍
Excellent!
Thanks for watching and Stay Tuned!
I love the comments about Subaru and the rod bearings and failures when in all reality it’s the factory rod bolts if you take stock sti rods. Put arp2000 rod bolts and then obviously hone and resize cuz it changes clearances, but every rod bearing failure I have had except the pickup tube failure was a factory rod bolt that has broken, stretched, or fretted from high torque runs. Once I fixed the rod bolts problem my issues went to broken ringlands. So now with my set up 100mm bore stock sti forged rods and 400ft lbs of torque I have had much more success, my Subaru runs and I’m proud to say IV blown up 22 Subaru motors and continuing, and they sit around 375-450 hp for 50-60 thousand miles on stock block ej257 they are tough engines, and if you don’t get greedy with horsepower numbers then you can have a very reliable car.
And if you have a rod failure it is mandatory you clean every part and flush every oil galley oil pan, cam gears in avcs and after first start run for 5 mins and change oil. Then repeat process, untill oil is clean. Do break in in driveway, oil cooler is impossible to clean has to be replaced IV tried, it’s pre filter so it doesn’t go to the rods but it does go through the oil pump. It can also plug up and cause your pump to be stuck in bypass and cavitate I do 3-4 oil changes in 100 miles after a spun bearing rebuild. Cleaned everything and have had really good luck. I think the factory oil cooler/warmer is part of the problem as well. Keeping oil temps at bay also help. How many subarus have spun a bearing but not realized their oil temp is at 260 degrees. This is also what bites people in the butt. Oil pressure gauges and temperature gauges are a must
Thanks for watching and thanks for the comment.
Stay Tuned!
Hey guys I would love to hear you talk about keeping the torque curve to the left of the chart. And moving the torque curve left if you feel it’s too far right. I have an oem turbo 2.5 wrx and would love to figure out how to get more bottom end
That is a good question. We have discussed it somewhat here:
th-cam.com/video/c-ZfPk75Tjg/w-d-xo.htmlsi=HQvky9oRLyvV_0qF
But this is always a good topic. I'll add it to the list.
Port your turbo, headers exhaust down pipe. And tune and you will increase spool. Also port waste gate so you can carry top end power. Also 4.44 gear swap to a 2006 wrx jdm tranny. That will make a torque monster
Great topic guys, I think the 6 qt oil pan from KillerB is a good improvement for a modified EJ as it increases likelihood that oil is available for the pickup tube and pump. Also an extra quart keeps the oil a little fresher during that 3000 mile interval. Quick question: Do you think an oem STI oil cooler added to the EJ255 will lower oil pressure with the stock 10mm oil pump? Thanks!
So, what is a good oil pressure gauge to use? Also, where is it best to install this to monitor the pressure?
Great question. We like the Innovate Oil Temp and Pressure dual gauge:
www.flatironstuning.com/innovate-mtx-d-dual-gauge-oil-pressure-temperature
A big reason is that you can get both of those important pieces of information from a single gauge.
We have been putting them in place of the factory "sensor". It works well, but the reading can move around a lot, so a damper can be a good idea as well.
Hope that helps and Stay Tuned!
I use the AEM (150PSI max) "X Series" oil pressure gauge and am pretty happy with it. Visual "bar graph", large numerical readout and programmable alarm.
@@FlatironsTuning thanks for the information! This is super helpful for my new build. What does the damper look like? And would it got in the oem sensor location first take like a flow meter resistor?
@@Nightdeath4223 Here is a link to the Prosport kit:
www.flatironstuning.com/prosport-remote-oil-pressure-sender-installation-kit
Basically it just puts the sensor further away from the block, so the pulses of pressure are smoothed out a bit.
These videos are great! Would a harmonic balancer like Fluidampr potentially extend bearing life?
Thanks for the question. Something like the Fluid Damper can be helpful on higher power cars, or cars that are revving higher. I wouldn't say it would extend bearing life though. If you want to keep vibration down, doing something like a dynamic balance of the rotating assembly would be the ideal way to do that.
Thanks for watching and Stay Tuned!
Thanks!@@FlatironsTuning
I have my car in the shop right now I thought is had rod knock sounded bad but they open my oil pan and found no metal shaving in there so they are looking into it more ? What else can it be
Could also be the timing belt tensioner. If it is loose, it can make a noise similar to rod knock..
Hope that helps!
Recommendations for thoroughly cleaning a killer B oil pan?
About stock subaru oil pressure sensor - don't you guys replace it with, say, mitsubishi sensor? it has 1bar pressure threshold... so the light becomes more informative then "your engine is dead"?
Thanks for the question. The Subaru light comes on around 16 psi which is higher than 1 Bar. I'd say rather than simply replacing it with a sensor that triggers at a single pressure, replacing it with a gauge that actually shows you what is happening in the engine is more ideal.
And if you can data-log that pressure, that is way better.
Thanks for watching and Stay Tuned!
Wat is a good oil pressure in a ej ?
How good is the stock oil pan/pickup/baffling for track days running stock configuration engine?
Upgrading the oiling system is more to do with mitigating the effects of G forces on the boxer engine than power level. If you are taking a long, high G turn with the stock setup, you are cruising for a bruising imo.
@@johnwesely I guess what I want to know is what are the limits of lateral G force for stock oil pan and is there any data for the iag and killer b setups for how much g force they can take, as well as any flaws in those aftermarket designs vs stock oiling system. Thanks
I've been taught from a young age to change my oil every 3 thousand miles and always fix your oil leaks, I'm 56 and have never blown an engine. also killer B told me to use 6 quarts of oil in my ej255, can you confirm that john? with killer B pan
If you're using a Killer B pan, I'd use Killer B's recommendation. They'd know better than anyone.
70 retired lineman diyer. Same here with my 2006 Subaru sti. Change the oil every 5000 miles on my 98 Honda prelude
Are there other times you would want to replace avcs cam gears other than a spun bearing?
Thanks for your question. There can certainly be errors that are thrown that are related to AVCS cam gears, and in those cases, it can be part of the diagnosis to change them.
I would generally say that you would want to take a look at oil pressure before simply changing out the gears, but it is possible that they could develop an issue over time.
Hope that helps and Stay Tuned!
So whats best journal bearings for the EJ platform?
That's how I spun a bearing, low oil, highway on ramp...😅
Ooof. Sorry to hear that.
Thanks for watching and hope you got your car up and running again.
Stay Tuned!
@@FlatironsTuning No, it was totally my fault. I knew it was low and shouldn't have pushed it on my way home. 😅