M8 problems
3rd Gear
Joined: Nov 2017
Posts: 7
Likes: 1
From: South Carolina
2017 Ultra M8 107, built Sep 2016. Not the Twin Cooled model, and has stage 1. At 11949 miles, Oil light came on and stays on at Idle once motor is warmed. Revving up the motor causes light to go away. Changed oil again, thinking it might be contaminated, (I had changed fluids at 1k, 5k, and 10k miles) Went through 3 tanks of gas and problem came back. Took to dealer, they put mechanical Oil Pressure Gage, and when bike is cold, everything is normal. Once the bike warms up 0 psi at idle. Tech Services told dealer to change Oil Pump and Cam. They did NOT authorize tear down and inspection of Motor. I had dealer upgrade to the Stage IV 114 while they had it partially apart. Two weeks later, they finally get the new oil pump in, and stage IV installed. Started bike to test drive, and after it warmed up it lost oil pressure at idle. Dealer will call Tech Services in morning to tell them I want new motor. Harley doesn't even authorize dealer to change oil and check drain plug for metal much less tear down and inspect. That is why I told them to put the upgrade in, I wanted to make sure as much of the motor as was possible to be new. I think Harley is going to try to go out the cheap way, so I believe I am going to have to fight for new motor. Everything but the Flywheel/Crank, block and oil pan has already been replaced.
I believe that there are metal shavings in some narrow passage for the oil is the culprit. Since the problem only occurs when bike is warm, I believe that when the shavings get warm they expand, therefore blocking the oil at idle to be picked up by the pump.
I believe that if HD had the larger capacity oil pans available for the M8, like they do for the earlier Twin Cams, it would most likely fix the problem along with the new oil pump. But since they haven't even done a tear down and inspection, I won't be satisfied with anything less than a new motor with matching VIN.
I believe that there are metal shavings in some narrow passage for the oil is the culprit. Since the problem only occurs when bike is warm, I believe that when the shavings get warm they expand, therefore blocking the oil at idle to be picked up by the pump.
I believe that if HD had the larger capacity oil pans available for the M8, like they do for the earlier Twin Cams, it would most likely fix the problem along with the new oil pump. But since they haven't even done a tear down and inspection, I won't be satisfied with anything less than a new motor with matching VIN.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
2017 Ultra M8 107, built Sep 2016. Not the Twin Cooled model, and has stage 1. At 11949 miles, Oil light came on and stays on at Idle once motor is warmed. Revving up the motor causes light to go away. Changed oil again, thinking it might be contaminated, (I had changed fluids at 1k, 5k, and 10k miles) Went through 3 tanks of gas and problem came back. Took to dealer, they put mechanical Oil Pressure Gage, and when bike is cold, everything is normal. Once the bike warms up 0 psi at idle. Tech Services told dealer to change Oil Pump and Cam. They did NOT authorize tear down and inspection of Motor. I had dealer upgrade to the Stage IV 114 while they had it partially apart. Two weeks later, they finally get the new oil pump in, and stage IV installed. Started bike to test drive, and after it warmed up it lost oil pressure at idle. Dealer will call Tech Services in morning to tell them I want new motor. Harley doesn't even authorize dealer to change oil and check drain plug for metal much less tear down and inspect. That is why I told them to put the upgrade in, I wanted to make sure as much of the motor as was possible to be new. I think Harley is going to try to go out the cheap way, so I believe I am going to have to fight for new motor. Everything but the Flywheel/Crank, block and oil pan has already been replaced.
I believe that there are metal shavings in some narrow passage for the oil is the culprit. Since the problem only occurs when bike is warm, I believe that when the shavings get warm they expand, therefore blocking the oil at idle to be picked up by the pump.
I believe that if HD had the larger capacity oil pans available for the M8, like they do for the earlier Twin Cams, it would most likely fix the problem along with the new oil pump. But since they haven't even done a tear down and inspection, I won't be satisfied with anything less than a new motor with matching VIN.
I believe that there are metal shavings in some narrow passage for the oil is the culprit. Since the problem only occurs when bike is warm, I believe that when the shavings get warm they expand, therefore blocking the oil at idle to be picked up by the pump.
I believe that if HD had the larger capacity oil pans available for the M8, like they do for the earlier Twin Cams, it would most likely fix the problem along with the new oil pump. But since they haven't even done a tear down and inspection, I won't be satisfied with anything less than a new motor with matching VIN.
What is more than likely true is that the oil cooled motors simply do not have any pressure at idle... There isn't any way to maintain pressure in the current oil cooled head system.. At idle all the oil flows through the head passages and pressure drops.. As far as I can tell the head flow is simply an orifice. As oil heats up, viscosity drops and more oil flows through the cooling lines to the heads. Pressure drops to 0.. They need a pressure / valve ball like on the oil jets..
Making an orifice smaller for the head cooling passage might help.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
2017 Ultra M8 107, built Sep 2016. Not the Twin Cooled model, and has stage 1. At 11949 miles, Oil light came on and stays on at Idle once motor is warmed. Revving up the motor causes light to go away. Changed oil again, thinking it might be contaminated, (I had changed fluids at 1k, 5k, and 10k miles) Went through 3 tanks of gas and problem came back. Took to dealer, they put mechanical Oil Pressure Gage, and when bike is cold, everything is normal. Once the bike warms up 0 psi at idle. Tech Services told dealer to change Oil Pump and Cam. They did NOT authorize tear down and inspection of Motor. I had dealer upgrade to the Stage IV 114 while they had it partially apart. Two weeks later, they finally get the new oil pump in, and stage IV installed. Started bike to test drive, and after it warmed up it lost oil pressure at idle. Dealer will call Tech Services in morning to tell them I want new motor. Harley doesn't even authorize dealer to change oil and check drain plug for metal much less tear down and inspect. That is why I told them to put the upgrade in, I wanted to make sure as much of the motor as was possible to be new. I think Harley is going to try to go out the cheap way, so I believe I am going to have to fight for new motor. Everything but the Flywheel/Crank, block and oil pan has already been replaced.
I believe that there are metal shavings in some narrow passage for the oil is the culprit. Since the problem only occurs when bike is warm, I believe that when the shavings get warm they expand, therefore blocking the oil at idle to be picked up by the pump.
I believe that if HD had the larger capacity oil pans available for the M8, like they do for the earlier Twin Cams, it would most likely fix the problem along with the new oil pump. But since they haven't even done a tear down and inspection, I won't be satisfied with anything less than a new motor with matching VIN.
I believe that there are metal shavings in some narrow passage for the oil is the culprit. Since the problem only occurs when bike is warm, I believe that when the shavings get warm they expand, therefore blocking the oil at idle to be picked up by the pump.
I believe that if HD had the larger capacity oil pans available for the M8, like they do for the earlier Twin Cams, it would most likely fix the problem along with the new oil pump. But since they haven't even done a tear down and inspection, I won't be satisfied with anything less than a new motor with matching VIN.
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,462
From: State of Confusion
What you are saying is not true.. Metal particles wont expand to block a passage.
What is more than likely true is that the oil cooled motors simply do not have any pressure at idle... There isn't any way to maintain pressure in the current oil cooled head system.. At idle all the oil flows through the head passages and pressure drops.. As far as I can tell the head flow is simply an orifice. As oil heats up, viscosity drops and more oil flows through the cooling lines to the heads. Pressure drops to 0.. They need a pressure / valve ball like on the oil jets..
Making an orifice smaller for the head cooling passage might help.
What is more than likely true is that the oil cooled motors simply do not have any pressure at idle... There isn't any way to maintain pressure in the current oil cooled head system.. At idle all the oil flows through the head passages and pressure drops.. As far as I can tell the head flow is simply an orifice. As oil heats up, viscosity drops and more oil flows through the cooling lines to the heads. Pressure drops to 0.. They need a pressure / valve ball like on the oil jets..
Making an orifice smaller for the head cooling passage might help.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
Oil pump is getting a little looser.. On thing to note is that the SM does specify 5 psi as idle speed pressure.. On the twin cooled motors I don't see this as a issue but on the oil cooled motors it's a balance between oil viscosity and flow through the heads.
Also,
Not sure this is correct..
Tech Services told dealer to change Oil Pump and Cam.
3rd Gear
Joined: Nov 2017
Posts: 7
Likes: 1
From: South Carolina
After all of my research, here is what I believe might be an issue. The M8 oil pump is stronger than previous models, at least according to Harleys own site. The filter is 5 micron, and more restrictive than older filters. The increased pressure is causing relief valve to open, BYPASSING the filter. Over time metallic particles are sent through the Oil Cooler, where they start to clog the cooler fins. The loss of oil pressure only occurs when the bike is warm, and at idle. When the oil heats up the small metallic particles will expand, restricting flow through the cooler.
They changed the Oil Pump, Cam, cam bracket, pistons, jugs, heads, push rods, and clutch. Problem still persists. I asked them to swap out oil cooler to prove my hypothesis, and dealer says to wait until they change the block, or Harley will say the problem is fixed and not replace the short block. Once the shortblock is installed, we will see if the light comes on before changing the oil cooler as a way to prove my theory.
The dealer put a mechanical gage on the bike, so we know it's not an electrical issue such as sending unit.
And the bike was built Sep 15 2016.
They changed the Oil Pump, Cam, cam bracket, pistons, jugs, heads, push rods, and clutch. Problem still persists. I asked them to swap out oil cooler to prove my hypothesis, and dealer says to wait until they change the block, or Harley will say the problem is fixed and not replace the short block. Once the shortblock is installed, we will see if the light comes on before changing the oil cooler as a way to prove my theory.
The dealer put a mechanical gage on the bike, so we know it's not an electrical issue such as sending unit.
And the bike was built Sep 15 2016.
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Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
After all of my research, here is what I believe might be an issue. The M8 oil pump is stronger than previous models, at least according to Harleys own site. The filter is 5 micron, and more restrictive than older filters. The increased pressure is causing relief valve to open, BYPASSING the filter. Over time metallic particles are sent through the Oil Cooler, where they start to clog the cooler fins. The loss of oil pressure only occurs when the bike is warm, and at idle. When the oil heats up the small metallic particles will expand, restricting flow through the cooler.
They changed the Oil Pump, Cam, cam bracket, pistons, jugs, heads, push rods, and clutch. Problem still persists. I asked them to swap out oil cooler to prove my hypothesis, and dealer says to wait until they change the block, or Harley will say the problem is fixed and not replace the short block. Once the shortblock is installed, we will see if the light comes on before changing the oil cooler as a way to prove my theory.
The dealer put a mechanical gage on the bike, so we know it's not an electrical issue such as sending unit.
And the bike was built Sep 15 2016.
They changed the Oil Pump, Cam, cam bracket, pistons, jugs, heads, push rods, and clutch. Problem still persists. I asked them to swap out oil cooler to prove my hypothesis, and dealer says to wait until they change the block, or Harley will say the problem is fixed and not replace the short block. Once the shortblock is installed, we will see if the light comes on before changing the oil cooler as a way to prove my theory.
The dealer put a mechanical gage on the bike, so we know it's not an electrical issue such as sending unit.
And the bike was built Sep 15 2016.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
After all of my research, here is what I believe might be an issue. The M8 oil pump is stronger than previous models, at least according to Harleys own site. The filter is 5 micron, and more restrictive than older filters. The increased pressure is causing relief valve to open, BYPASSING the filter. Over time metallic particles are sent through the Oil Cooler, where they start to clog the cooler fins. The loss of oil pressure only occurs when the bike is warm, and at idle. When the oil heats up the small metallic particles will expand, restricting flow through the cooler.
They changed the Oil Pump, Cam, cam bracket, pistons, jugs, heads, push rods, and clutch. Problem still persists. I asked them to swap out oil cooler to prove my hypothesis, and dealer says to wait until they change the block, or Harley will say the problem is fixed and not replace the short block. Once the shortblock is installed, we will see if the light comes on before changing the oil cooler as a way to prove my theory.
The dealer put a mechanical gage on the bike, so we know it's not an electrical issue such as sending unit.
And the bike was built Sep 15 2016.
They changed the Oil Pump, Cam, cam bracket, pistons, jugs, heads, push rods, and clutch. Problem still persists. I asked them to swap out oil cooler to prove my hypothesis, and dealer says to wait until they change the block, or Harley will say the problem is fixed and not replace the short block. Once the shortblock is installed, we will see if the light comes on before changing the oil cooler as a way to prove my theory.
The dealer put a mechanical gage on the bike, so we know it's not an electrical issue such as sending unit.
And the bike was built Sep 15 2016.