M8 problems
HD EFI Guru
Joined: Jan 2008
Posts: 4,489
Likes: 4,776
Both pumps are pretty much the same with one change in them. The pump housing is machined for a different supply element. The Twin Cool uses a smaller supply element than the oil cooled does. The rest of the pump is the same. From a design standpoint one would not fail more than the other.
So if a oil cooled pump was placed into a Twin cooled you would have way to much supply pump and if the Twin cooled was put into the Oil cooled way to little. The suction side is the exact same on both as is the relief valve.
So if a oil cooled pump was placed into a Twin cooled you would have way to much supply pump and if the Twin cooled was put into the Oil cooled way to little. The suction side is the exact same on both as is the relief valve.
Advanced
Joined: Apr 2017
Posts: 57
Likes: 10
From: So Cal
I was ready to pull the trigger on a new roadglide ultra, but am going to wait. This oil pump problem is way to common. Hopefully they will have it figured out soon. Any of these having any coolant loss issues also? Thanks
Stellar HDF Member
Joined: May 2015
Posts: 2,902
Likes: 443
From: West Tennessee
I'm with you on this. There is something funky going on as oil pumps are not that complicated. Hopefully Harley has at least some clue as to what is causing this and has a permanent fix. This should never happen!!!
Road Master
Joined: Dec 2009
Posts: 843
Likes: 43
From: Louisiana
Well after 2 weeks at the dealer this time Harley tech support is suppose to call my dealer back in the next few days to schedule a factory rep visit. He'll work along side the dealer mechanic to dig deeper. Geez I wonder if they'll pull the oil pump.
Last edited by LA VIC; May 26, 2017 at 11:21 PM.
Seasoned HDF Member
Joined: Oct 2014
Posts: 5,073
Likes: 2,382
From: Camp Lejeune, NC
Just out of curiosity, how many posts have you seen and personal accounts have you heard about this "way too common" oil pump issue? If it's less than 10, you're just adding more cow chips to the hyperbole fire.
Advanced
Joined: Jan 2008
Posts: 77
Likes: 4
From: Metro Detroit
Your loss. I'll be enjoying all the miles my M8 is racking up.
Just out of curiosity, how many posts have you seen and personal accounts have you heard about this "way too common" oil pump issue? If it's less than 10, you're just adding more cow chips to the hyperbole fire.
Just out of curiosity, how many posts have you seen and personal accounts have you heard about this "way too common" oil pump issue? If it's less than 10, you're just adding more cow chips to the hyperbole fire.
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Ultimate HDF Member
Joined: Jul 2014
Posts: 5,649
Likes: 430
From: MASS_hole
Your loss. I'll be enjoying all the miles my M8 is racking up.
Just out of curiosity, how many posts have you seen and personal accounts have you heard about this "way too common" oil pump issue? If it's less than 10, you're just adding more cow chips to the hyperbole fire.
Just out of curiosity, how many posts have you seen and personal accounts have you heard about this "way too common" oil pump issue? If it's less than 10, you're just adding more cow chips to the hyperbole fire.
after all, if you base your opinion off of this thread relating to m8 issues. Then that's all you'll learn about the bike. Altho, it would be nice to know what the actual oercentage of m8 are having issues and which they relate to
Cruiser
Joined: Oct 2013
Posts: 237
Likes: 6
From: Jones
Shop did not bleed the coolant correctly, air bubbles left which let the coolant overheat. They could not reproduce the low oil light.
I guess I will be riding it again.
Thank you
FrankEGD
I guess I will be riding it again.
Thank you
FrankEGD
So, after they've replaced the oil pump, new gasket for rear rocker cover and dropped it of, I haven't had time for a test ride. But yesterday I did go for a quick ride.
About 15 mls into it, the water temp light and check engine light came on, As soon as I pulled into a gas station the oil light came on too. Again!
I called the shop and they came and picked up the bike. They guy that was loading the bike ran the strap around the water line on the right hand side. When he tightened it, it started leaking... Great.
Just waiting on them to call me today.
Thannk you
FrankEGD
About 15 mls into it, the water temp light and check engine light came on, As soon as I pulled into a gas station the oil light came on too. Again!
I called the shop and they came and picked up the bike. They guy that was loading the bike ran the strap around the water line on the right hand side. When he tightened it, it started leaking... Great.
Just waiting on them to call me today.
Thannk you
FrankEGD