Starter noise
Supporter
Joined: Mar 2020
Posts: 1,007
Likes: 598
From: Northeast Louisiana
Could be 1 compression release not opening.🤷♂️ Then when you tested it got worse as now both not working.
I would do a compression test on both cylinders to see what they are doing on starting.
Get engine to normal operating temperature, remove pugs connect Compression tester, throttle held wide open (TBW, so improvise holding blade open with something safe), turn engine over until needle stops going up.
With ACR`s connected 130-170 PSI
With ACR`s disconnected 200-220 PSI.
Of course that's assuming a standard engine config, if you have done changes (head work/head gasket/pistons/cams).
Last edited by Bayou FLHR-M8-128"; Dec 26, 2023 at 07:31 AM.
I appreciate the input.
HDF Community Team
Joined: Mar 2008
Posts: 1,892
Likes: 551
From: NH
Thanks for the reply, and the expected cylinder pressures. I unplugged the CRs one at a time so i could tell that they are both making a difference. The bike is starting OK now that the battery has been replaced, I'm focusing more on the grinding noise at this point.
I appreciate the input.
I appreciate the input.
HDF Community Team
Joined: Nov 2012
Posts: 6,186
Likes: 2,412
From: USA
Not being a Harley expert I thought they all did that. Crank over and all but stall the starter motor on the first compression stroke. Then crank better, but still lumpy, until the engine fired up. Sometimes taking a few seconds.
Once something got fixed, the starter spun the engine over more quickly, and more smoothly. The engine fired up quicker too.
Once something got fixed, the starter spun the engine over more quickly, and more smoothly. The engine fired up quicker too.
Stellar HDF Member
Joined: Aug 2020
Posts: 3,159
Likes: 2,202
From: College Station, TX
You initial thought on the noise was that the bendix teeth were still contacting the ring gear after the engine starts and the starter button is released. I suspect that is correct, although you likely need to remove the outer primary to confirm that. Some visual, and at some point removing the clutch hub to inspect for worn or damaged parts. If you haven't already, you could drain the primary oil and check for metal fragments attached to the magnetic drain plug, which you would need to do if you decide to remove the outer cover.
Since the ring gear is attached to the clutch basket, I'd also check the hub bearing for an slack. And look closely at the inner primary behind and around the ring gear for any contact marks. If there are marks, that should serve as a hint that something is going on there. There have been some cases where the clutch hub splines have cracked and broken, allowing the assembly to move.
It is curious that the original starter doesn't make the noise, while both orthers do. No explanation for that other than tolerances or incorrect assembly.
Paul
Since the ring gear is attached to the clutch basket, I'd also check the hub bearing for an slack. And look closely at the inner primary behind and around the ring gear for any contact marks. If there are marks, that should serve as a hint that something is going on there. There have been some cases where the clutch hub splines have cracked and broken, allowing the assembly to move.
It is curious that the original starter doesn't make the noise, while both orthers do. No explanation for that other than tolerances or incorrect assembly.
Paul
Last edited by pgreer; Dec 26, 2023 at 01:53 PM.
Seasoned HDF Member
Joined: Oct 2015
Posts: 8,459
Likes: 19,160
From: The Republic of Texas
Your initial post and beginning statements, sounds similar to what I recently experienced. On my 2012 FLHX, at 35,000 original miles, my starter was acting up like yours. I thought it was a worn starter Clutch Hub, so I purchased one from JP Cycles and replaced it. The original starter clutch hub did not look usual from wear or anything else.
With the new starter clutch hub, the engine started fine but made an unusual grinding noise, similar to what you described. I immediately turned the engine off and started scratching my head. I later started the engine again, with the same constant grinding noise, not real loud or abrasive but, kind of a whining, grinding noise. I then removed the Starter and inspected the clutch ring gear and starter pinion gear, both looked good. I removed the new clutch hub assy. I cleaned up the original clutch hub, re-lubed, and re-assembled the Starter. I reinstalled the original starter and clutch hub assembly, and haven't had a problem since but, haven't ridden it much either. If it happens again I plan to rebuild the whole Starter assembly.
.
With the new starter clutch hub, the engine started fine but made an unusual grinding noise, similar to what you described. I immediately turned the engine off and started scratching my head. I later started the engine again, with the same constant grinding noise, not real loud or abrasive but, kind of a whining, grinding noise. I then removed the Starter and inspected the clutch ring gear and starter pinion gear, both looked good. I removed the new clutch hub assy. I cleaned up the original clutch hub, re-lubed, and re-assembled the Starter. I reinstalled the original starter and clutch hub assembly, and haven't had a problem since but, haven't ridden it much either. If it happens again I plan to rebuild the whole Starter assembly.
.
Grand HDF Member
Joined: Jan 2012
Posts: 4,445
Likes: 2,813
From: Oklahoma
Did your starter rebuild include new contacts and plunger disc in the starter solenoid? My previous bike did not have compression releases. I developed the habit of having it in gear and pushing to backward until I was stopped by compression, then starting. That seemed to give the engine and starter a little extra inertia to spin through the first compression stroke. Do ACRs get dirty and not release as much pressure as they did when new? Perhaps someone here knows.
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Seasoned HDF Member
Joined: Mar 2021
Posts: 17,894
Likes: 3,551
From: backwoods
Probably works better on a carbed bike, but I would if starter was getting weak or battery low, quick tap the start button to let compression off. Some ignitions could be programed to fire. Not sure why they don't do that more.
HDF Community Team
Joined: Jan 2022
Posts: 1,111
Likes: 855
From: B.C.
You are starting your bike at “much below freezing” ?
Are you starting in gear?
What is the viscosity of the engine oil?
What are you using for oil in the primary?
No answers, only more questions.
Not trying to create an oil thread, but it may be something to look at.
Colder temperatures will put more load on the starter due to the thicker viscosity of the oil.
And no, you don’t need to break in a starter.
Are you starting in gear?
What is the viscosity of the engine oil?
What are you using for oil in the primary?
No answers, only more questions.
Not trying to create an oil thread, but it may be something to look at.
Colder temperatures will put more load on the starter due to the thicker viscosity of the oil.
And no, you don’t need to break in a starter.