That's amazing but scary information! Wow! I could easily see that happening to me and I'm very thorough and careful in my approach! Then again, I typically leave the advanced stuff to the pros. Good stuff, Doc!
Great info DOC Harley , I recently did the heads on my twin cam for the first time and I was lucky to spot this problem in time I also found out another place is the cam cover and oil pump bolt holes where oil will puddle up into some of the holes , I clean the holes out with a Q-tip and Yes it's a great idea to always clean out any holes on your motorcycle that collects oil before threading any bolt into them , that could save a person a headache , time and money.. Thanks alot DOC Harley 👍💯
Wow. Such a small thing can lead to a big problem. I did mine a few years ago and cleaned the bolt holes so the loctite would adhere better. I’m glad I did!
Thanks for the tip, Doc. Nothing hurts the heart like installing a bolt and hearing a "POP!". It's amazing how much force can be generated by a 1/4"-20 bolt on a confined fluid. I learned my lesson years ago when putting the primary cover back on my 73' Sportster after rebuilding the clutch. I'm spinning the bolts in with a tee handle allen wrench, just bringing up to contact when I hear the "POP", and I see old silicone coming out of a crack in the case like little blue hairs growing before my eyes. My heart dropped to my toes. Luckily the crack was just between the bolt hole and the outside of the case. I was able to put sealer over the crack and finish the summer before tearing it down and getting it welded. That was the day I became religious about cleaning the threads on every bolt and bolt hole I deal with. The previous owner was a big fan of silicone, asI discovered when I rebuilt the motor. But the damage was my fault for not being meticulous in my work. Silicone is not oil, but they behave the same when put under pressure with no where to go.
Conversely, would, say, a 1/32 drill hole through the centre of the fastener help by allowing pressurised trapped oil to escape as it was being fastened? The drill hole could be cleaned out of old sealant if need be. Mind you I do realise a cotton bud would be a lot easier, just barn-storming. Cheers
At the moment you said the bolt started to slow down but still goes in, I guessed oil was in the whole. Simple air gun to cleaner it out works. Can't believe that casting can break with that light of torque. Those bolts do look like they are longer than they really need to be.
It’s not so much about the torque of the bolt as much as the hydrologic pressure. I did some tests years ago with different cast aluminum pieces like aluminum differential cousins and aluminum cylinder heads on small engines. I put different gasket maker and different viscosity oils on the threads and in the hole in different amounts. What I found was the smaller the width of the hole, the faster the casting craked. The overall depth of the hole wasn’t as important as the hole diameter. Obviously this was just some bs test I conducted with scrap parts but it really opened up my eyes on how fast things can go bad when we aren’t paying attention to the little things. No go out and get you some scrap pieces and start destroying stuff in the name of science!
Holy Crap. Way to ruin your day in the most innocent way thinking your are doing yourself a favor while learning something new. Thanks for the heads up ! Very important info.
Thank you for the reminder I dont think I am taking that serous enough. I have a rear rocker gasket leaking/weeping and I read to clean out oil from holes but I have now made note in my service manual for when I decide I am going to fix my bike.
Been there done that I heard it break I found the piece that broke off Cleaned it up / jb weld it in place. A little thread sealant on the bolt 80+k on the repair never leaked Lesson learned Now I blow every single hole out with air no matter where on the bike it is!!!
Excellent tech tip Doc!-I upgraded my breathers a couple of years ago and did not check your tip-I must of been lucky or just used break cleaner to clear the holes.
Did it on 1 of my first jobs 😢 Cleaned and silicone was a good temp fix until we got a new one to replace it. Lesson learned. Great tip, always love the videos ❤
Thanks Doc for a very valuable tip!!!!! That's working like a brake line.... you can compress air but not liquid. I hope you and the family had a great Christmas together and wishing you a Happy New Year!!!
I have learned my lessons working with dirty holes, this is just another reminder to use thread chasers and shop air to make sure I don't go sticking my bolt in a dirty hole and end up paying the price.
As soon as I saw the thumb nail I knew what this vid was about lol I’m amoung the meatheads that did this. I heard a little plink sound when I tightened that bolt and I learnt a lesson that day. I mixed up some jb weld on the end of a popsicle stick, smeared it around the underside of the casting and let it cure. That was 12yrs ago and I haven’t had the leak since….I’m also sure to blow out blind holes now before threading a bolt into it.
Thank You Doc for that good information. when did Harley change over to the newer breathers as I know in the older twin cams they had that older breather style. which I changed to the newer style in my 01 ultra about 3 years ago. So do you know when Harley switch over to the newer style breather as I have a 2011 ultra 110 CVO now. cuz I know I could look in the parts manual to find out. but it might help others to know when they switched.
Probably would have never guessed that oil in a bolt hole would have created a problem. Now I'll be checking any and all bolt holes for any kind of debris before inserting a bolt.
Every bolt, when removed, needs the threads cleaned and dry before reassemble, including derby cover bolt holes! I can't tell you how many derby cover bolt holes I've seen stripped!😂
Those derby cover bolts are soft as hell on the head. I think the torque specs are a little high for what they are tho. I’ve had one get stuck coming out and strip the head .. thread portion was fine it was the head that basically welded itself to the derby cover (not TECHNICALLY welded of course .. just stuck from riding hard in hot weather it got mad hot and that thing wasn’t turning at all.) Cut the head off with a little grinder and the threaded stud left was able to be pulled out with just my fingers (had a needed nose vice grip ready but wasn’t needed at all). I won’t reuse those bolts more than once (the one time I was cheap and let em ride for 3 primary oil changes .. I do every 4k with the oil and tranny .. cheap insurance
@geraldgoodiii6993 58 years of riding and I've never stripped one. I've repaired many. The proper use and care of tools should provide many years of service. I think the issue is people have a tendency to overtorque when attaching or not properly preparing each screw and or screw hole as doc says. Most screws, bolts, and attachment points today are of aluminum and soft metals. Back in the old days things were made of iron and steel. They were more forgiving.
Great warning. Also, make sure the shop gives you the correct NEW screws. Don't use the old ones. The new breather boxes are much lower profile, and the old screws will push out the bottom of the holes as they are much longer than the new screws. You missed the opportunity to point that out.
That's amazing but scary information! Wow! I could easily see that happening to me and I'm very thorough and careful in my approach! Then again, I typically leave the advanced stuff to the pros. Good stuff, Doc!
Thank Dr Harley keep up the great shows and tips ps Gods blessings to you and all your family
I truly appreciate the blessings…Doc
Thank you for sharing all you years of experience! Saving us 100's, 1000's of dollars and all the frustration
Great info DOC Harley , I recently did the heads on my twin cam for the first time and I was lucky to spot this problem in time I also found out another place is the cam cover and oil pump bolt holes where oil will puddle up into some of the holes , I clean the holes out with a Q-tip and Yes it's a great idea to always clean out any holes on your motorcycle that collects oil before threading any bolt into them , that could save a person a headache , time and money.. Thanks alot DOC Harley 👍💯
Thanks for the pointer.
Excellent tip Doc!! Thanks
Great post, AS ALWAYS, Doc. Thank you so much and Happy New Year!!!! Me and my Twin Cam can't thank you enough!!
Thank you for watching and support…Doc
Wow. Such a small thing can lead to a big problem. I did mine a few years ago and cleaned the bolt holes so the loctite would adhere better. I’m glad I did!
Well done….Doc
Thank's, again, Doc.
As usual, a couple of visuals and your synchronized diologue, a real helpful piece of cake.
Cheers all around with that beer.
I appreciate you watching and your support….Doc
Thank you for trying to save us from costly errors, greatly appreciated!!!
Thanks Doc. I'm about to put mine back together and didn't know this.
Glad you caught that before assembly…..Doc
very good point Doc, liquids can't be compressed so something has to give. 👍👍
Thanks for the tip, Doc.
Nothing hurts the heart like installing a bolt and hearing a "POP!". It's amazing how much force can be generated by a 1/4"-20 bolt on a confined fluid.
I learned my lesson years ago when putting the primary cover back on my 73' Sportster after rebuilding the clutch.
I'm spinning the bolts in with a tee handle allen wrench, just bringing up to contact when I hear the "POP", and I see old silicone coming out of a crack in the case like little blue hairs growing before my eyes. My heart dropped to my toes.
Luckily the crack was just between the bolt hole and the outside of the case. I was able to put sealer over the crack and finish the summer before tearing it down and getting it welded.
That was the day I became religious about cleaning the threads on every bolt and bolt hole I deal with. The previous owner was a big fan of silicone, asI discovered when I rebuilt the motor. But the damage was my fault for not being meticulous in my work.
Silicone is not oil, but they behave the same when put under pressure with no where to go.
Conversely, would, say, a 1/32 drill hole through the centre of the fastener help by allowing pressurised trapped oil to escape as it was being fastened?
The drill hole could be cleaned out of old sealant if need be. Mind you I do realise a cotton bud would be a lot easier, just barn-storming.
Cheers
@edharbas4828
I clean them out with the correct size tap and then blow it out with compressed air. I've never had a problem after doing that.
Thank you for taking the time to post your experience….Doc
Great advice & tech tip, thanks for sharing.
Thank you for watching John…Doc
At the moment you said the bolt started to slow down but still goes in, I guessed oil was in the whole. Simple air gun to cleaner it out works. Can't believe that casting can break with that light of torque. Those bolts do look like they are longer than they really need to be.
It’s not so much about the torque of the bolt as much as the hydrologic pressure.
I did some tests years ago with different cast aluminum pieces like aluminum differential cousins and aluminum cylinder heads on small engines. I put different gasket maker and different viscosity oils on the threads and in the hole in different amounts.
What I found was the smaller the width of the hole, the faster the casting craked. The overall depth of the hole wasn’t as important as the hole diameter.
Obviously this was just some bs test I conducted with scrap parts but it really opened up my eyes on how fast things can go bad when we aren’t paying attention to the little things.
No go out and get you some scrap pieces and start destroying stuff in the name of science!
Hi Doc, thank you very much for this. It's a brillant information for everyone doing it for the first time.
Greetings from overseas, Germany 😉✌️
Thanks for your post from Germany…Doc
Holy Crap.
Way to ruin your day in the most innocent way thinking your are doing yourself a favor while learning something new.
Thanks for the heads up ! Very important info.
Thank you for the reminder I dont think I am taking that serous enough. I have a rear rocker gasket leaking/weeping and I read to clean out oil from holes but I have now made note in my service manual for when I decide I am going to fix my bike.
You're welcome, good luck with the project…Doc
A Service Manual!! The tool most DIY guys won’t invest in.
Great info, have noted it in my service log. Thank for posting this video. 👍
Thanks for watching John….Doc
Been there done that
I heard it break
I found the piece that broke off
Cleaned it up / jb weld it in place.
A little thread sealant on the bolt
80+k on the repair never leaked
Lesson learned
Now I blow every single hole out with air no matter where on the bike it is!!!
Thanks for sharing Randy….Doc
Great reminder to clean out ALL blind holes. Thanx!
Brilliant thank you Doc
Excellent tech tip Doc!-I upgraded my breathers a couple of years ago and did not check your tip-I must of been lucky or just used break cleaner to clear the holes.
Glad it worked out for you….Doc
Now that is a dang good tech tip right there.
Thank you so much.
👍😎👍
Thank you Roy…Doc
This is why these videos are so great. Thank you, sir.
I appreciate your post….Doc
Thank You Doc Harley! And thank you for taking time to meet and talk with me.
You’re very welcome and a pleasure to talk with you…Doc
Thanks Doc. I’m making a note of it right now in my service manual.
FYI: The new head breather kit comes with shorter bolts but you still need to clean those holes out.
First one I broke it popped really loud and an oil mess everywhere. Expensive mistake. Now I do exactly what you said. 😊
Just in time Doc! I'm doing this job on my bike next week and didn't know this.
I'm glad I could help…Doc
Awesomeness!! Thanks for that.😊
You’re welcome, and thanks for watching….Doc
Thanks Doc.
Merry Christmas and Happy New Year!
You too, and thanks for watching…Doc
Excellent tip Doc, thanks for taking the time to share. Cheers
Great tip as always. Thanks Doc.
You’re welcome Brad, keep watching…Doc
Very useful info !! Thanks much !! I just had mine replaced. I’m glad the Harley dealer did it now. !!
Thanks for Tips and I never knew about this... you are man DOC ! Have a happy Holiday !!
Thanks. Happy New Year….Doc
That's good to know for sure . Thank you for your channel .
Thanks for watching…Doc
I just blew a bolt out when replacing the breathers. I threw gasket maker into the hole and tightened down. Good to go, zero issues since.
Any chance you carry a 4 leaf clover with you?…..Doc
That's a good one Doc. Thanks for the great advice.
Ride safe from Sydney Australia 🤘
Glad you enjoyed it…Doc
Did it on 1 of my first jobs 😢
Cleaned and silicone was a good temp fix until we got a new one to replace it.
Lesson learned. Great tip, always love the videos ❤
I know that feeling from my early days…Doc
@LowCountryHarleyDavidson
Indeed. Live, and learn 😍
Best to you and yours. Hope you had a good Christmas season.
Classic! As a wiser man than me once said " a little bit of knowledge is a dangerous thing!"
Don’t use the same bolts either the old breather has longer bolts. The new breather has shorter bolts. FYI. ✊🏻✊🏻✊🏻
If short bolts why then would it blow out casting
I think I'm OK, but I'm definitely going to check that!
I've always been able to thread those down all the way by hand
Never knew.....Thanks Doc
Thanks Doc for a very valuable tip!!!!! That's working like a brake line.... you can compress air but not liquid. I hope you and the family had a great Christmas together and wishing you a Happy New Year!!!
You are very welcome, and happy new year…Doc
Thanks for another great video doc.
Glad you enjoyed it Scott…Doc
I have learned my lessons working with dirty holes, this is just another reminder to use thread chasers and shop air to make sure I don't go sticking my bolt in a dirty hole and end up paying the price.
Hanks for the tip as always Doc. Great job.
You are welcome Gordon…Doc
What a great tip, thank you doc Harley!
Glad it was helpful…Doc
Another good tip. Happy New Year Doc.
Happy New Year to you too…Doc
Thanks Doc you are appreciated big time.
You are very welcome…Doc
Hope you had a great Christmas Doc. Happy new year !
Happy New Year to you as well…Doc
Thanks Doc that helps out a lot
It’s all about the tricks when working on the Harley. Thank you.
I am glad you liked it, thanks for watching….Doc
Another excellent tip Doc. Hope you continue to educate us home mechanics. Hope you have a good New Year.
Thanks, you too…Doc
Excellent. This begs the question, what are the symptoms that your breathers need replacing?
Take the time to find one of our earliest videos on this question….Doc
Thanks, Doc. , I enjoyed hearing all your advice .
I appreciate your time watching…Doc
Thanks Doc...
Thumbs up for the channel...
😎👍
I appreciate it. Thanks for watching….Doc
Ty Doc good info Happy Christmas and have a great New Year keep your videos coning
You're welcome, happy holidays to you as well…Doc
Ouch! Thanks for the video Doc!
Well,.....that was a real eye opener. Thanks Doc.
Great word Doc!
Thanks James….Doc
Well now there’s a great tip!
Thank you Doc.
😎👍🍻
Thanks for watching Allen ….Doc
Thx Doc. Great to know. I'm changing mine this winter. Just saved my ass
I am glad it helped…..Doc
Thanks for the warning, my 96ci thanks you also.
Glad you got the message…Doc
Great video and tip as usual Doc Harley!
Thanks for watching…Doc
Merry Christmas 🎅 Doc from Alaska!
In my opinion what I saw was the new one made the bolts longer! The old one was thicker making the bolt short the right length
Preciate that tip doc. I never gave that a thought.
Cheers from Italy, Doc!☺️
Gracie….Doc
@LowCountryHarleyDavidson ❤️💪🏻
Wow that's crazy, the unknown....
Thanks for sharing that,what a headache that could be.
Thanks Doc, Australia 🇦🇺
Always glad to hear from across the pond👍….Doc
Once again, Doc, great information.
Thanks for watching…..Doc
Thanks heaps Doc!! Still a legend 🙌
Thanks, but far from Legend just a man on UA-cam….Doc
As soon as I saw the thumb nail I knew what this vid was about lol
I’m amoung the meatheads that did this. I heard a little plink sound when I tightened that bolt and I learnt a lesson that day. I mixed up some jb weld on the end of a popsicle stick, smeared it around the underside of the casting and let it cure. That was 12yrs ago and I haven’t had the leak since….I’m also sure to blow out blind holes now before threading a bolt into it.
Thank for sharing your experience…Doc
Excellent Doc.
Many thanks Doug….Doc
Thank You Doc for that good information.
when did Harley change over to the newer breathers as I know in the older twin cams they had that older breather style. which I changed to the newer style in my 01 ultra about 3 years ago. So do you know when Harley switch over to the newer style breather as I have a 2011 ultra 110 CVO now. cuz I know I could look in the parts manual to find out. but it might help others to know when they switched.
Great advice Doc.
Thanks for watching and posting. Doc
Always great information Doc, Merry Christmas and Happy New Year to you and yours!🎄
Thank you and the same to you….Doc
🤯 wow thats crazy & good to know thanks. Even though I don’t do any of my own repairs.
Thanks for watching, you never know when you might….Doc
Thanks Doc. Another great tip.
Thanks for another great video enjoy the holidays
Thanks, you too….Doc
great video. thanks for the heads up.
Well done sir..
Thanks Curt….Doc
@LowCountryHarleyDavidson I try to be good student when smart people like you talk Doc. I've got a newer 103.
Very good to know Thanks Doc
Thank you Doc.
You are very welcome Michael…Doc
Thanks Doc. Great info. Great video.
You are welcome…..Doc
Much respect from Minnesota
SPORTSTER4LIFE 🍀
Great to hear from you…Doc
Yes, at the school of hard knocks 😂 I wasn't always the sharpest spoon in the drawer 😢
👍….Doc
Great video thanks hope you had great christmas and happy new year
Thanks I did and the same to you…Doc
Q-Tips clean them holes out thats an easy way or air or suction
You’re right, there are a lot of ways to clean those holes….Doc
Probably would have never guessed that oil in a bolt hole would have created a problem. Now I'll be checking any and all bolt holes for any kind of debris before inserting a bolt.
It can be a real pain but it can also be a good thing to do….Doc
Well butter my biscuit Doc just taught this ol' dog something new...Thanks Doc
You’re never too old to learn….Doc
Thank you!
Every bolt, when removed, needs the threads cleaned and dry before reassemble, including derby cover bolt holes! I can't tell you how many derby cover bolt holes I've seen stripped!😂
You're absolutely right. A little time there can save a lot of trouble….Doc
Those derby cover bolts are soft as hell on the head. I think the torque specs are a little high for what they are tho.
I’ve had one get stuck coming out and strip the head .. thread portion was fine it was the head that basically welded itself to the derby cover (not TECHNICALLY welded of course .. just stuck from riding hard in hot weather it got mad hot and that thing wasn’t turning at all.)
Cut the head off with a little grinder and the threaded stud left was able to be pulled out with just my fingers (had a needed nose vice grip ready but wasn’t needed at all).
I won’t reuse those bolts more than once (the one time I was cheap and let em ride for 3 primary oil changes .. I do every 4k with the oil and tranny .. cheap insurance
@geraldgoodiii6993 58 years of riding and I've never stripped one. I've repaired many. The proper use and care of tools should provide many years of service. I think the issue is people have a tendency to overtorque when attaching or not properly preparing each screw and or screw hole as doc says. Most screws, bolts, and attachment points today are of aluminum and soft metals. Back in the old days things were made of iron and steel. They were more forgiving.
Thats a GREAT tip thanks.
Great tip thanks
Great warning. Also, make sure the shop gives you the correct NEW screws. Don't use the old ones. The new breather boxes are much lower profile, and the old screws will push out the bottom of the holes as they are much longer than the new screws. You missed the opportunity to point that out.
Thanks for the tip, I'll keep that in mind for future videos…Doc
WOW WOW doc beer how can we work with out the good stuff glad we have you but take it easy with the beer thank you for tips tho
I'll try to stay focused…Doc
Thanks for this awesome tip!
You can try blowing it out with compressed air! Merry Christmas from Lexington S.C.
Merry Christmas from Doc Harley!
Thanks Doc. Wondering why you didn't just hit the holes with air. Also curious how the DEI heat shield inserts worked for the officer. Cheers.
My dear friend. Last week we posted the officer’s review. ( not everyone has a compressor for air assist)….Doc
@LowCountryHarleyDavidson thanks. Missed the review. Will watch.