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Primary isolation

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Old Nov 3, 2022 | 09:38 PM
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Default Primary isolation

I have a 1976 FLH. Been working on getting bike on road. Long story short, got bike road worthy took two short rides of 30 miles everything went well, next ride was 100 miles. Parked bike, next morning major leak from behind sprocket. Started tear down, discovered previous owner/owners did isolate the primary. I’ve read the “shovelhead us. article and the “Hawg” diagram. Which leads to my questions. In the first photo the primary return #1 is blocked, # 2 is blocked #3 the small diameter pipe is used as the vent?. On my bike the small diameter pipe #3 has a screw lodged in it blocking it which I think created pressure and caused the outer primary gasket to leak on the bottom near the drain plug. Also the primary line # 1 was still connected to pump with no block, left open under bike tucked away. # 2 that hose had a bolt stuck in the line with a clamp on it . The small line #3 was connected to the inner primary but the fitting in the inner primary had the screw. I guess what I’m asking is #3 the proper vent, just add a short hose and position under bike. On the pump how do you block the unused lines, the fittings look like they are pressed in, I read somewhere using short hose and bolt, seems very unsightly. Does any one make a rubber boot or plug. Or must the cover come off and fittings be removed, holes tapped? Any help always appreciated.

My case , notice the fitting is pointed up, if this is the vent any issue repositioning it to point down rather than have a longer line attached and risk a kink?

My cover, blocked off chain oiler, which I think caused pressure build up in primary leading to leaks.

Not my cover but numbered things nicely #3 is the vent?
 
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Old Nov 3, 2022 | 10:04 PM
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I used number three on mine - minus the phillips screw of course.
 
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Old Nov 3, 2022 | 10:09 PM
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Yup #3 makes a nice vent, do a 180 bend on the hose downward. Won't stop a little weep but less mess in general and doesn't blow past the gaskets or starter bendix seat that way.
 
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Old Nov 4, 2022 | 07:22 AM
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Screw should be removed from #3 and I removed the hose from backside.. I connected a small length of hose between the two small ports on the pump rather than install plugs. Zoom in to see the loop in the photo. Also here is another diagram of the routing.



 
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Old Nov 4, 2022 | 09:29 AM
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I don't bother anymore.. From experience... Longevity does Not seem to be Much Affected.. Seems it Should... But... Certainly Not Proven.
So... If already done?? Cool, If Stock?? That is cool too... I have at least One Each.. Highest Mileage was an '83 FLHT...Bone Stock except Carburetor (CV) 63K.
Save yer breath on all of the "Sure Seems Like" Show your Shovelhead, Mileage Differential.
 
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Old Nov 4, 2022 | 02:03 PM
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Default Primary isolation

Thank you everyone, answered my questions. Since the isolation was almost correct decided to finish it. Diagram was great, just confirmed my thoughts. Pulling oil tank for a through cleaning, transmission also to replace seals and clean. Head start on winter repairs.
 
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Old Nov 4, 2022 | 02:12 PM
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Originally Posted by 76HDflh
Thank you everyone, answered my questions. Since the isolation was almost correct decided to finish it. Diagram was great, just confirmed my thoughts. Pulling oil tank for a through cleaning, transmission also to replace seals and clean. Head start on winter repairs.
Get a long screwdriver and about 16" of 1/4" rod you can bend up a bit for digging the hard chunks out of the corners in oil bag, you'll be surprised what will come out.
 
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Old Nov 4, 2022 | 04:33 PM
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Originally Posted by 76HDflh
Thank you everyone, answered my questions. Since the isolation was almost correct decided to finish it. Diagram was great, just confirmed my thoughts. Pulling oil tank for a through cleaning, transmission also to replace seals and clean. Head start on winter repairs.
what a pain to get that oil tank out
 
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Old Nov 4, 2022 | 06:53 PM
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Originally Posted by john lee
what a pain to get that oil tank out
Nuthin but a Thing...If yer pullin Tranny anyway...
 
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Old Nov 5, 2022 | 08:52 AM
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when it's all going together again, use new fixings, clips screws & Nuts so it's easier next time.
The Moco didnt seem to think of the Mechanic when they designed things, no wonder that custom up-grades & kits to keep things simple are out there,
 
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