ATF in the transmission? Never seen that on a Harley before.

Was ATF, now what?

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RooDog
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Re: ATF in the transmission? Never seen that on a Harley before.

#16

Post by RooDog »

panheadrider1961 wrote: Thu Jun 30, 2022 5:21 pm Have you rode the motorcycle with it in there?
ATF is a high detergent based fluid it should be super clean inside , if ridden usual third gear slight whine is normal , siren sound not good this will be bronze bushing bad ,drain and add 1.5 pints as manual specs and use 60 weight oil if on hand ride and if no siren in 3rd should be ok
OE Shovelhead transmissions do not have bronze bushing in the MS 3rd gear. That ended with the 1958 model year.
The newer gear is solid steel with a longer hub that extends deeper into its mating main shaft cluster gear. This does away with the poorly designed bronze bushed 3rd gear of ages past. The later gear may be retrofitted with the older MS cluster if one took the time to grind back the center hub to equal the length of the older 3rd gear. I have done exactly that, and it worked out OK for me. But I subsequently replaced with Andrews 1st & 3rd gears. Now listed for sale in the Classified section
....RooDog....
Last edited by RooDog on Sat Aug 27, 2022 3:23 pm, edited 1 time in total.
1957flhchop
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Re: ATF in the transmission? Never seen that on a Harley before.

#17

Post by 1957flhchop »

panheadrider1961 wrote: Thu Jun 30, 2022 5:21 pm Have you rode the motorcycle with it in their?
ATF is a high detergent based fluid it should be super clean inside , if ridden usual third gear slight whine is normal , siren sound not good this will be bronze bushing bad ,drain and add 1.5 pints as manual specs and use 60 weight oil if on hand ride and if no siren in 3rd should be ok
I did not ride it with the ATF in it. I drained it and replaced with engine oil. I don't know about noises yet as I just got it running last weekend and only rode up and down my street a couple times before another potential issue with the bike arose.
1957flhchop
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Re: ATF in the transmission? Never seen that on a Harley before.

#18

Post by 1957flhchop »

doc9339 wrote: Thu Jun 02, 2022 9:02 pm If your plug is an actual pipe plug, they are tapped with NPT (National Pipe Thread) and is a tappered fit and will eventually crack your tranny case: Get rid of it. Previous owner most likely lost the origional drain plug, or the threads in the case got stripped out so he went the pipe plug route, a bad idea
Just realized I didn't post anything further regarding the plug.

I ordered the correct plug, but the threads were no even close to the same. The threads on the "correct" replacement were waaayyyyy more coarse than the pipe plug. I wasn't wild about running a tap up in there to make the replacement plug work because I figured the only way I would ever get all the pieces of metal out then would be to disassemble the transmission. I stuck the pipe plug back in temporarily until I figure out what to do.
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Re: ATF in the transmission? Never seen that on a Harley before.

#19

Post by nifty »

Live with your taper thread pipe plug, use some oil friendly sealant, Permatex #2 works for me, torque to 10ftlb max and you won't split case, or lose plug.
If you gorilla-over-torque you will split case
If you are paranoid drill & safety wire plug.
The coarse thread 707 trans drain plug is 1/2" 13 UNC, originally used as very early WL trans filler plug, only 2-3 threads engagement in BT trans drain, small head & flange for joke cupped brass washer, earlier BT drains were 3/8" UNF and later 1/2" UNF which I prefer because of more thread engagement and easy availability of larger hex heads and better sealing washers.
A good operator can helicoil a stripped 1/2" UNC to pristine 1/2" UNF, with trans in bike, a bad operator will screw it up so trans has to come out, be stripped completely and boogered hole welded & re-machined, hence leave what you have.
If you helicoil to 1/2" UNC you still only have 2-3 threads, plus original 707 plug can't be used as OD of installed coil is right there at small flange.
Nifty
Last edited by nifty on Tue Jul 05, 2022 12:18 am, edited 2 times in total.
1957flhchop
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Re: ATF in the transmission? Never seen that on a Harley before.

#20

Post by 1957flhchop »

nifty wrote: Tue Jul 05, 2022 12:04 am Live with your taper thread pipe plug, use some oil friendly sealant, Permatex #2 works for me, torque to 10ftlb and you won't split case, or lose plug.
I just tightened it by feel since I couldn't get a socket of a torque wrench near there. The hard steel brake line is too close to get on it(without bending the line). I had to tighten it about a 1/3 turn at a time with a small(I think it was 3/8" head on the plug) end wrench slipped between the frame and the bottom of the transmission.
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Re: ATF in the transmission? Never seen that on a Harley before.

#21

Post by Andygears »

For the next time, you may be able to get a straight pipe thread Allen head plug that you could use one of those ball head drivers at an angle. If the trans is tapered female and the plug tapered male, it will tighten sooner than with a straight thread plug. A little more engagement with good sealer should be oil tite.

Andygears
1957flhchop
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Re: ATF in the transmission? Never seen that on a Harley before.

#22

Post by 1957flhchop »

Andygears wrote: Tue Jul 05, 2022 12:47 am ...you may be able to get a straight pipe thread Allen head plug that you could use one of those ball head drivers at an angle.
Thanks for the idea! Hadn't even considered one of those.
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Re: ATF in the transmission? Never seen that on a Harley before.

#23

Post by db13 »

doc9339 wrote: Thu Jun 02, 2022 9:04 pm 50wt motor oil in a shovel tranny I dont beleive is correct. I beleive it should be gear oil, around 80-90wt. Do some research and use the correct wt and oil. WHat year is yiour bike?
50 wt motor oil is what the Harley owner manual calls for in a Shovelhead transmission.
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