Author Topic: Sump Plate - loose studs & sealing  (Read 1075 times)

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ducati2242

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Re: Sump Plate - loose studs & sealing
« Reply #15 on: 07 May, 2018, 18:28:33 »
Helicoiled mine and then loctited new studs in . Worked fine .
1956 bsa GS DB500
1967 bsa B44
1955 matchless G9
2006 ducati 999R .

hoogerbooger

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Re: Sump Plate - loose studs & sealing
« Reply #16 on: 07 May, 2018, 18:39:49 »
I realise that ultimately helicoil may be necessary. But this s probably beyond me currently and if it can be done with the engine in the bike I'd need a professional with a decent lift. Hoping I can do something in the interim to get it running ....then I can size up what needs doing for a more decent restoration.

I used Granville Bearing Fit and stud lock.- It's a red one saying it is permanent.


hoogerbooger

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Re: Sump Plate - loose studs & sealing
« Reply #17 on: 11 May, 2018, 18:16:35 »
Just tried using bsf nyloc nuts and it started winding in a 3rd stud & on unwinding took the stud out ! !

the nut went on a reasonably way  so I think these nuts were bsf threads ( as they were sold to me). Standard Bsf nuts seem to go on fine.....So I seem to have no choice (presuming I can get the stud to threadlock ok ) but to use standard nuts and spring washers.

This likely to be leak proof ?


MALCOLM.JOHNSON

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Re: Sump Plate - loose studs & sealing
« Reply #18 on: 13 May, 2018, 21:32:02 »
You are lucky that 1/4 inch BSF is exactly the same as 1/4 inch cycle thread (BCY) which is 26 TPI and a 60 degree thread form. Do not try BSF to the other BCY sizes, as they DO NOT interchange. Bolt it up and get riding. If it leaks a little it proves you had oil in! ;D

AWJDThumper

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Re: Sump Plate - loose studs & sealing
« Reply #19 on: 14 May, 2018, 07:45:34 »
Strictly speaking, the 1/4" thread forms are not the same: BSF (and BSW) has a 55 deg thread angle whereas BSC has a 60 deg thread angle in the same way as metric threads. That said, I've never found any problems in using them interchangeably.

hoogerbooger

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Re: Sump Plate - loose studs & sealing
« Reply #20 on: 14 May, 2018, 15:13:44 »
points noted on the differing thread angle. Thanks.

Sounds like Malcolm thinks the risk is a bit of a leak rather than a lot ? A small amount of leakage seems bearable  ( & perhaps traditional !) Do you think I can be pretty sure it shouldn't be more than a small amount of leakage with spring washers ?

(Would nyloc nuts always have been used on 1960's sumps studs ? or have they come in later as a less shake proof option ? )




AWJDThumper

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Re: Sump Plate - loose studs & sealing
« Reply #21 on: 14 May, 2018, 17:01:05 »
I'm not really clear whether the threads in the crankcase have failed or are still in reasonable condition. If a thread has failed, the use of thread lock will not work in which case you have no choice but to repair the threads affected with a Helicoil. If the threads are ok, it should be possible (as a test) to use suitably long BSF bolts with lock washers on them to clamp the sump plate in place. If the threads are ok, it should be possible to tighten them to a torque of about 10Nm. The reason bolts weren't used originally is that they tend to wear out the threads in the soft ally crankcase after repeated use.

In terms of the type of lock nut used, Nyloc nuts weren't around in the 1960's but are the modern replacement for the sump plate nuts. I think the original ones were cleveloc or aerotight locking nuts.

hoogerbooger

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Re: Sump Plate - loose studs & sealing
« Reply #22 on: 14 May, 2018, 18:46:11 »
I take it you mean use the bolts to test if I can fit sump to 10NM.

Then if that works I ought to be able to fit studs with thread lock .

By lock washers do you mean rectangular spring washers ?

I don't think the threads have failed, as I wouldn't have been able on the one to over tighten it.. so that it carried on going in for 5mm too far. Seems like the threadlock is not working well. ( Granville bearing fit & studlock)

(One other studs started turning inwards after I'd threadlocked it...seemingly when the nyloc section was engaged the stud. I stopped as soon as I saw it start turning.... and that stud ended up coming out)

I guess it could be an old rubbish batch of the product although I bought it online recently) .
Was also wondering whether the internal surface wasn' clean enough; or whether all the carburettor cleaner hadn't evaporaaed off; or whether there is wear on the threads so that the gap to fill is bigger .


AWJDThumper

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Re: Sump Plate - loose studs & sealing
« Reply #23 on: 15 May, 2018, 07:51:43 »
Using bolts will test that the threads are still ok - use spring washers to stop them unscrewing. If the threads are ok then there should be no reason why the studs can't be locked in place. I would recommend high strength Loctite 270 but clean the threads beforehand as well as you can to remove any oil film. Squirting brake cleaning fluid into the threads and using some cotton buds should normally do the trick. If brake cleaning fluid is not available then substitute some other solvent.

hoogerbooger

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Re: Sump Plate - loose studs & sealing
« Reply #24 on: 17 May, 2018, 18:18:36 »
Thanks for all the advice.

right size spring washers arrived. So sump plate back on. No torque wrench so have just had to judge it ( but might borrow/buy cheep one to check if 10NM)

No sign of studs turning. Had repeated using Carb cleaner the Granville bearing fit & studlock. I hadn't previously been using much torque when the studs turned with nyloc nuts... so not that confident the threadlocker will prevent them shaking free...but we'll see. If/when I get the bike going I'll be doing some standing tests and very short trips with regular checks for leaks/movement.

All advice banked as I may need to use if the studs fail.  Thanks again.

( I am leaning gradually ! .... and progress is slowly being made !)


MALCOLM.JOHNSON

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Re: Sump Plate - loose studs & sealing
« Reply #25 on: 18 May, 2018, 10:44:27 »
I have been out of commission a few days and just seen I had some brain flatulence re thread angle of BSF. Over 70 (that is years not MPH) and it seems to happen more often. I am sure hoogerbooger has the main theme of my post. Hope it all seals up for you. Happy riding.

OVERTHEHILL

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Re: Sump Plate - loose studs & sealing
« Reply #26 on: 18 May, 2018, 20:52:19 »
Just been reading this thread, if the studs are fitted with locktite and you use spring washers and standard nuts all will be well. That's what I use and oil does not leak. That's what was used when the bikes were new only they did not use locktite just screwed the studs in. Do not overtighten use a short spanner and modest pressure.