I looked for a spin on adapter for my bike but cannot find any.
A serious oil pressure question
- Thread starter djlinux64
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I have no idea what the best oil is but i read a lot of folks are using Rotella T Synthetic 15w40 with good results in bike engines.It appears to handle the shearing effects of the transmission well.
30 psi at 4,000 should be enough so the engine doesn't grenade itself as long as there is adequate flow,while not as high as spec it will probably be ok.
30 psi at 4,000 should be enough so the engine doesn't grenade itself as long as there is adequate flow,while not as high as spec it will probably be ok.
You mean clearances not tolerances look up the words in a dictionary tolerance has nothing to do with oil pressure and volume needed clearance of the parts does.
First what oil viscosity does the manaul state to use for takeing the oil pressure reading. This is very very important. For instance many of GM's vechiles that recomend 5W30 the shop manual calls for 10W30 when testing the oil pump for pressure because that is what they used inthe lab. So if I had 5W30 in the sump and my numbers where off that very well could the cause.
For all you know the oil pressure guage you are useing could be wrong as well? One of the perks when I worked for GM was that the paid for my tools to be calibrated once a year some tools more often then that. In fact my Torque wrench has not been calibrated since I lost my job with them none of my tools have been!
With the difference you are seeing I do not think it is the oil to be honest I would expect a higher reading to be honest. I think you either have an issue with the oil pump or your gage. My oil pump gage was made by Bosch and has Swarovski Hand cut Crystal lens and are designed for a lifetime of use and re-calibrations same thing with my Micrometer set. On the other hand I bought a cheap ball type bore gage set of ebay for $23 and I do not expect it to be precise and it is not designed to be recalibrate on a regular basis. Cheap oil pressure gages are usually not that accurate.
I suspect your bypass is stuck partial open or the gears are worn on the oil pump and this is what is causing your problem. So use another gage and if the problem is still their you what you need to do!
First what oil viscosity does the manaul state to use for takeing the oil pressure reading. This is very very important. For instance many of GM's vechiles that recomend 5W30 the shop manual calls for 10W30 when testing the oil pump for pressure because that is what they used inthe lab. So if I had 5W30 in the sump and my numbers where off that very well could the cause.
For all you know the oil pressure guage you are useing could be wrong as well? One of the perks when I worked for GM was that the paid for my tools to be calibrated once a year some tools more often then that. In fact my Torque wrench has not been calibrated since I lost my job with them none of my tools have been!
With the difference you are seeing I do not think it is the oil to be honest I would expect a higher reading to be honest. I think you either have an issue with the oil pump or your gage. My oil pump gage was made by Bosch and has Swarovski Hand cut Crystal lens and are designed for a lifetime of use and re-calibrations same thing with my Micrometer set. On the other hand I bought a cheap ball type bore gage set of ebay for $23 and I do not expect it to be precise and it is not designed to be recalibrate on a regular basis. Cheap oil pressure gages are usually not that accurate.
I suspect your bypass is stuck partial open or the gears are worn on the oil pump and this is what is causing your problem. So use another gage and if the problem is still their you what you need to do!
Originally Posted By: djlinux64
1/4 quart of Castrol Syntec 5w-50. PSI is up from 18 psi to 30-35 at the manual spec 4000 rpm @ 50 psi @ 194F.
Why not just change the oil, it doesn't take much, then you'll know?
1/4 quart of Castrol Syntec 5w-50. PSI is up from 18 psi to 30-35 at the manual spec 4000 rpm @ 50 psi @ 194F.
Why not just change the oil, it doesn't take much, then you'll know?
John and everyone else that has responded, thank you all very much! I really appreciate the help you guys offer for my oil pressure issue. I really don't want this engine to grenade and I started to worry after I saw some seriously unnaturally polished camshafts and one pitted lobe that had developed since last valve check (every 3000 mi). (On a side note, I tend to run this engine continuously close to red line for hours at a time, but I am changing my gearing tomorrow to change that). I will get my gauge checked out and see if it still shows correct pressure.
I only added 400 mL of 5w-50 oil and my pressure went from 18 psi to 30-35 psi @ 4000 rpm. The sump takes around 1.4 L. I am optimistically looking forward to my next oil change when I will try running pure Castrol 5w-50. If the trend continues, I should be well in spec that time. In addition, since 5w-50 is within the allowed viscosity specification, that will mean good news to me because it most likely does not need a new pump. They do not specify which oil to measure pressure with. For all I know they can be using the 20w-50! Hopefully the gauge is accurate enough to register such a difference meaningfully. Thanks again!
I only added 400 mL of 5w-50 oil and my pressure went from 18 psi to 30-35 psi @ 4000 rpm. The sump takes around 1.4 L. I am optimistically looking forward to my next oil change when I will try running pure Castrol 5w-50. If the trend continues, I should be well in spec that time. In addition, since 5w-50 is within the allowed viscosity specification, that will mean good news to me because it most likely does not need a new pump. They do not specify which oil to measure pressure with. For all I know they can be using the 20w-50! Hopefully the gauge is accurate enough to register such a difference meaningfully. Thanks again!
Originally Posted By: westwind999
Originally Posted By: djlinux64
1/4 quart of Castrol Syntec 5w-50. PSI is up from 18 psi to 30-35 at the manual spec 4000 rpm @ 50 psi @ 194F.
Why not just change the oil, it doesn't take much, then you'll know?
Because I put in 2 quarts of really expensive nice Redline 10W40 ;-) Right now I have enough pressure at higher rpm to run the oil another few thousand. Not sure about RL since I just switched my bike over, but usually every oil burns in this bike. I don't think there is any other four stroke that is such a ridiculous oil grinder.
Originally Posted By: djlinux64
1/4 quart of Castrol Syntec 5w-50. PSI is up from 18 psi to 30-35 at the manual spec 4000 rpm @ 50 psi @ 194F.
Why not just change the oil, it doesn't take much, then you'll know?
Because I put in 2 quarts of really expensive nice Redline 10W40 ;-) Right now I have enough pressure at higher rpm to run the oil another few thousand. Not sure about RL since I just switched my bike over, but usually every oil burns in this bike. I don't think there is any other four stroke that is such a ridiculous oil grinder.
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Originally Posted By: djlinux64
Not sure about the hours, but it has approx 23,000 miles on it and 300 miles on the 10W40 oil.
I am truly stumped. I actually added some pre-load washers to the pressure relief spring this morning to raise my pressure. The relief normally opens at 65 psi. The relief must be closed for the pressure to reach 75 psi. The relief cannot be open especially to meet the pressure numbers I see at the top end.
This behavior is exactly what a stuck open relief will do. The pump can overcome the relief volume at high rpms but not at low rpms so you see a huge fluctuation from low rpm pressure to high rpm pressure. If this were a viscosity issue you would be seeing something more like 30psi at 8,000rpm going by what it has at 4,000rpm. You said yourself the relief normally opens at 65psi yet you're seeing 75psi.
Not sure about the hours, but it has approx 23,000 miles on it and 300 miles on the 10W40 oil.
I am truly stumped. I actually added some pre-load washers to the pressure relief spring this morning to raise my pressure. The relief normally opens at 65 psi. The relief must be closed for the pressure to reach 75 psi. The relief cannot be open especially to meet the pressure numbers I see at the top end.
This behavior is exactly what a stuck open relief will do. The pump can overcome the relief volume at high rpms but not at low rpms so you see a huge fluctuation from low rpm pressure to high rpm pressure. If this were a viscosity issue you would be seeing something more like 30psi at 8,000rpm going by what it has at 4,000rpm. You said yourself the relief normally opens at 65psi yet you're seeing 75psi.
I am going to double check the relief. I shimmed the spring to keep it shut at higher pressures but we'll see if anything is messed up. Thanks again everyone.
I stared at the OEM manual for about a full hour re-reading the section on engine lubrication a few times when it struck me like a semi: I was tapping the pressure at the wrong location. There is a separate gallery bolt that is used to check engine pressure according to the manufacturer.
Let us know the pressure readings for the new tap location. Reason I suggested it may be the wrong location is your original statement "...an oil pressure gauge that I installed in between the bottom end and the top end." It just didn't seem like the right spot.
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