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Technical (Descriptive Topic Titles - Stay on Topic) => Frame => Topic started by: Worty on 02.09. 2018 12:41

Title: Engine mounts - arghhh
Post by: Worty on 02.09. 2018 12:41
Afternoon fellas.

Returned from my mega run yesterday (245m or 200m depending on whether you believe the trip or odometer reading).  Found that I'd lost four engine mount nuts and one complete bolt (upper rear bolt and nuts completely gone, lower nuts gone but bolt half out).  Any suggestions as to how I combat this.  Originally lost a couple of nuts but put split washers on and checked them before and after every run - seemed reasonably ok.  Would star/anti-rattle washers be better?  Should I use a combo of thread locker and star washers?  Should I weld the b****y thing up *angry*  Are there any other clever suggestions that I'm not capable of thinking up.  Have got boxes of bolts I can adapt to sort out the missing items, but don't really want to lose more if I can help it.
Title: Re: Engine mounts - arghhh
Post by: Rex on 02.09. 2018 13:08
Thread locker (Loctite)...do it once and forget about the regular retighten task.
Title: Re: Engine mounts - arghhh
Post by: Worty on 02.09. 2018 13:18
I will Rex, I will  *pull hair out* *pull hair out*
Title: Re: Engine mounts - arghhh
Post by: Triton Thrasher on 02.09. 2018 13:56
Forget any sort of spring washers or star washers.  They may be part of your problem.  Loctite, lock nuts or self-locking nuts probably will help.

It also helps to have original spec fasteners, tight in all the holes.  Some dodgy stainless kits have been marketed.
Title: Re: Engine mounts - arghhh
Post by: Black Sheep on 02.09. 2018 14:13
Nyloc nuts should do the trick. It is important the bolts are a snug fit in the holes and the threads are in good condition. Do you have a vibration problem? I really would not expect your nuts to drop off quite so easily...
Title: Re: Engine mounts - arghhh
Post by: Greybeard on 02.09. 2018 14:29
I really would not expect your nuts to drop off quite so easily...
Oh Matron!

Can you buy Nyloc nuts for Imperial threads?
Title: Re: Engine mounts - arghhh
Post by: berger on 02.09. 2018 14:43
I have not been to the pub YET! greybeard yes you can I've got nylocks on the 6 spring clutch, they have worked really well too *smile*
Title: Re: Engine mounts - arghhh
Post by: coater87 on 02.09. 2018 15:33
 Use the thickest flat washer I can find on everything...lock washers, start washers,...I have just never had any luck with them.

 clean the threads and inside the nut really well with brake clean.

 Shake up the threadlock.

 Then tighten them down tighter than you think. then hit them again with more torque.

 The best advice I ever received about tightening bolts on specialty cars:

 Go back and loosen off some of the bolts you had just done- you will be shocked at how "untite" they are. Reason is everything is covered in new paint and chrome, you have a lot of time invested. broken, stripped stuff is expensive. You are barely going over finger tight with the torque because you dont want any problems or ruined paint, you dont realize your doing it but you are.

 Try to think of your beautiful bike as a dirty old street sweeper while you are torquing things down. *ex*

Lee

 
Title: Re: Engine mounts - arghhh
Post by: scotty on 02.09. 2018 15:36
Also check your frame to cylinder head brackets (head steady)

Title: Re: Engine mounts - arghhh
Post by: a10 gf on 02.09. 2018 16:23
This: https://www.a7a10.net/forum/index.php?topic=1401.msg9869

Quote
As bolt or nut may try to unscrew itself, the surfaces will move against each other and expand in a way to lock everything even tighter and stop the process.

Funny things, the more things gets lose, the more they get tight :O)

wedge loch washers, Wurth (https://eshop.wuerth.de/Product-categories/Wedge-lock-washer/140135160301.cyid/1401.cgid)


Title: Re: Engine mounts - arghhh
Post by: Black Sheep on 02.09. 2018 18:34
No problem getting cycle thread locknuts. Nooky's Nuts amongst others stock them. Handy to know that if your nuts drop off you can get newer better ones.
Title: Re: Engine mounts - arghhh
Post by: bsa-bill on 02.09. 2018 18:37
Quote
Can you buy Nyloc nuts for Imperial threads?


ditto Black sheep, I use them, specially on places like the carb where you don't want to pull them up too tight but be sure they're not gonna come off
Title: Re: Engine mounts - arghhh
Post by: Worty on 02.09. 2018 22:16
All comments welcome, thanks.  I searched around in the shed and found some threaded bar (metric sadly) a perfect length/gauge to replace the one I lost (thanks to my old dad for hoarding piles of junk).  I also found a couple of unused nylocs which were the correct size.  Was interesting getting the nut on the primary side, used a ring spanner and a couple of screwdrivers to get the thread started.  That should sort the upper mounting.  As for the bottom, I cleaned the threads, applied a load of threadlocker, and belted them up good.  Everything else, including head steady bolts seem ok. Have used Nooky's before, looks like a revisit is coming up. 
Title: Re: Engine mounts - arghhh
Post by: KiwiGF on 03.09. 2018 00:17
All comments welcome, thanks.  I searched around in the shed and found some threaded bar (metric sadly) a perfect length/gauge to replace the one I lost (thanks to my old dad for hoarding piles of junk).  I also found a couple of unused nylocs which were the correct size.  Was interesting getting the nut on the primary side, used a ring spanner and a couple of screwdrivers to get the thread started.  That should sort the upper mounting.  As for the bottom, I cleaned the threads, applied a load of threadlocker, and belted them up good.  Everything else, including head steady bolts seem ok. Have used Nooky's before, looks like a revisit is coming up.

If you can fit 10mm studs in the bike then the holes are worn and this may explain why things are coming loose, an old racer once told me it was pretty standard to run a drill through old British engine/plates and use 10mm studs as it “tightened” things up nicely. Obviously if you want to stick to imperial (eg cycle thread) you would not want to do this!
Title: Re: Engine mounts - arghhh
Post by: berger on 03.09. 2018 03:02
I have been to the pub-------but, don't use threaded bar, the vibes hammer the threads into the casting and when you need it to come out it says  *work* and apart from that its bad practice lad as my dad told me *smiley4*
Title: Re: Engine mounts - arghhh
Post by: Black Sheep on 03.09. 2018 06:36
Metric threaded bar. Oh dear, naughty chair for you. Fit the correct items and save yourself a lot of grief. Any of the reputable suppliers will provide a set of correct set of engine studs and bolts. Don't be a cheapskate. Do it properly! I almost added FFS...
Title: Re: Engine mounts - arghhh
Post by: Worty on 03.09. 2018 08:08
Problem is, I like the bike to be out on the road more than I do seeing it broken (again) in the garage. *sad2*  TBH, I'm getting past the point of paying a small fortune for bits that are going to end up on the road.  The stud's a temp fix to get me on the road again, despite the (well received) warnings.  I lost the metal battery strap down the road some time ago, and found an old leather belt with thick rubber matting top and bottom almost eliminated vibration (and battery failure) and meant the battery wasn't doing a jig under my seat - works a treat!  I've had quite a lot of failures so far so am working out fixes on the way- some conventional, some not. 

Cheers again all, let me know if anyone has a spare engine mount *smile*
Title: Re: Engine mounts - arghhh
Post by: Peter Gee on 16.09. 2018 20:41
The answers are three.......loctite,loctite and loctite
Title: Re: Engine mounts - arghhh
Post by: Worty on 16.09. 2018 21:15
Point taken Peter, but I reckon I'll be spending a lot on Loctite!
Title: Re: Engine mounts - arghhh
Post by: a10 gf on 16.09. 2018 21:44
Loctite, yes & maybe according to what and where, but, repeating my posts in case some has missed them, try to get some wedge washers, and get an aha & wow moment.

Have used them on cars\bikes. it's the high-tech solution to vibration consequences. They were mandatory for vibration prone equipment at the factory I used to work, building mechanics\electronics for army\navy\oil platforms.

Correctly mounted (torque), they simply don't come lose, on the contrary, if some losening unexpectedly should occur, these washers starts their intended work, locking things with more strength the more things try to get lose.
For disassembling, one solid wrench movement to break the locks, replace with new washers when reassembling.

https://www.a7a10.net/forum/index.php?action=dlattach;topic=1401.0;attach=3087;image

Self securing wedge lockwashers
https://eshop.wuerth.de/Product-categories/Wedge-lock-washer/140135160301.cyid/1401.cgid
Title: Re: Engine mounts - arghhh
Post by: Daithi on 17.09. 2018 19:24
Quote
Should I weld the b****y thing up *angry*
You could weld one of the nuts to the stud creating a bolt.
Lots of stainless nylock imperial nuts on ebay and not to expensive.
Some good info here......
http://stainlessbits.com/link12.html (http://stainlessbits.com/link12.html)
 *grins* D