Britbike forum Forums British Motorcycle specific Brands Triumph bulletin board How to stop oil and gear box drain plug leaks?

Yes, yes...if it's British and it doesn't leak oil it's not running. That aside, I'd like to address a dripping leak from both my engine drain and gear box drain plugs. I'm concerned about over tightening them, and don't have a blow torch (or skill) to heat up the brass washers to make a perfect seal. Is there something I can spray on the seals that will be removable at the next oil change?

I don't mind some oil sweating, but drips are a no no at my office, where I'm making a pig's breakfast (mess) of the boss' new driveway.

Matt -
IMHO, since each drain plug is different, each calls for a different solution. Here's what I've worked out over thee last 40 years...

- The engine sump can be permanently sealed, since it should not be removed during regular service. That means adding a sealant to the threads of the plug and both sides of the copper washer before insertion.

- I like to use the copper washers from the rocker boxes on the oil tank drain plugs. The red paper ones slowly degrade, whereas the copper one last forever. Nylon is also a good coice here too.

- On gearbox drain plugs I like to install a nylon flat washer generally available at good hardware stores. The nylon is oil resistant, does not degrade, is soft enough to seal well (conform to surface irregularities) under moderate torque, is reuseable, and seems to have a slight rebound that keeps the plugs tight. There is a certain washer Lowes sells that is 1/2" ID and about .09 thick that is simply wonderful for this job.

- The primary drain plug is another matter. I've seen so many of these strip out that I am VERY afraid to apply any torque to this bolt. (Most people mistakenly equate not leaking with 10,000 ft-lbs of torque.) I simply use an o-ring and tighten the plug to snug. It might be good for a drop now and again, but nothing like the supreme headache of having a stripped out case!

Hope this helps! :bigt:

RFW, You know those alum washers.. they use on the late model 250's upper end? They would be the ones that have a rubber seal in the I.D. anyway if you stack ten or so on a bolt and use a nut and get them all stacked tight you can turn them on a lathe to the right O.D. so that they can be used on the primary cover screw that is also the drain. Now just normal tightness will stop a leak. Thank's for this trick from Doc BSA. Also I have found that any cover that's had an SHCS set installed needs to be re-spotfaced with a counter bore to get the bosses flat agian.

I have been using copper washers. The small ones you can heat hot enough with a butane lighter. Physics, chem books aside, we quench with water, or nitric acid solution. (You can even use vinegar).

However, the best has been a smear of Permatex anearobic gasket maker, blue or purple. Not a drop or seep of oil. We pretty much use the stuff everywhere, as it takes less, and is easier to apply than the high performance RTV which means less stringy stuff floating around in the engine.

Every time I am in the states, I pick up what I need. Probably available everywhere over there, but usually in the small tubes. I pick it up at NAPA in the 4 oz though...HTH...JK

I looked at the Permatex RTV today, but thought I'd go home and see if anything's loose first. Well, the sump plug needed a full half turn, and the gear-box drain and level plugs also needed a little tightening. Once I get my oil burn issue dealt with, I'll see if this settles the leak.

I bought a plastic box of various imperial size fibre washers and use a fresh one whenever a plug is removed, [including the front fork] the one for the primary case drain has to be trimmed to OD but I have not cut a finger off yet.
You can avoid a lot of drain plug removing by using a stirrup pump type vacuum sump sucker on the primary and oil tank.

I got a permatex stick thread sealer. It's like plumbers putty. I used it to seal the fork plugs, and primary case drain screws, and I used it on the oil pressure relief valve threads. It worked fine and the plugs are still easy to remove.
And I'm with you Matt, I think it's easy to resign yourself to leaks, take the well travelled path of "oh well, Brit bikes leak", but after chasing down a ton of leaks and fixing them proper, mine only makes the slightest drip when hot from the front sprocket cover.
Gunk

Matt,
Here's another Permatex product I discovered a couple of years ago. Its called THREAD SEALANT with TEFLON. Its similar to that white tape plumbers use, only its in a tube like the RTV products. I got it at an auto parts store and its used on male threads. I use the stuff on all those oil change type threads & gas petcocks and it works great for closing up all those tiny weeping areas. "Ahh" the quest for an oil tight machine!
Skeet

Hello Mr. Whatley...
I read the excellent article about sealing the primary case that you posted to the GABMA web site . In the article, you suggest that most pre-1970 English bikes have an orifice that taps off primary case oil and drips it onto the rear drive chain. I own a 1969 Bonneville. Where would I find that orifice in my primary chain case? I think that my bike is exhibiting the symptom that you suggest: a huge mess being slung over the rear of the bike by the drive chain. I have turned off the auto-oiler in the oil reservoir, so I'm wondering if that other orifice is causing my issue.

Thanks again for all the great articles that you've posted on GABMA.

Cheers!
Brian

Hi Brian, The chain oiler orfice was only used a short time. As I recall there was a service information to close it off if customer complained of leaks.

The '69 Bonnie I have apart doesn't have one.
Don

Hi Matt, For the engine sump try fitting an 70-8782 oring from primary cover plugs. Viton one is best. I was advised that a few years ago on RAT forum to 100% success. My 73 Tiger had rubber o-ring new, but parts books show copper seal which always leaked. Aluminum seal leaked also. The copper or aluminum washers always dripped some. I don't use any washer now, just the o-ring. It's too small & needs to be stretched on, but has worked for me. My original o-ring finally just deteriorated so that's when I went with the others. This o-ring fits & looks like the original.

I have alum. seal on trans, does not leak. I've used copper also, no leaks. I don't need sealant on this one.

My primary chain adjuster plug came with o-ring from new. Did not leak. No part # in book for o-ring. All the normal seals leaked. Yes over tighten will strip threads. I ended up using copper seal from Mercedes car that happened to fit. Applied hardening sealant to ring, cleaned well & tightened gently. No leaks. Silicon sealer on seal ring, not threads worked good also. Hardware store O-rings didn't fit the same & leaked or bolt didn't tighten properly since ring was too fat.

Our local coffee house hates oil leaks. I know what you mean. Took a while, but I've finally got a leak free bike.
Don

Hi Don,

Ahem ... regrettably Brian revived an 11-year-old zombie thread about a different range ...

Matt has a 500; both crankcase and primary cover drains are completely different from the 650 or 750. Both on the C-range were always originally fibre washers, ime both work well, probably because the advice is not to touch the crankcase drain, and I change either as a matter of course if the relevant plug is unscrewed; while they work, it's remembering to source and experiment with non-standard O-rings ...

Regards,

Hi Stuart,
It sounds like I may have done something wrong. I apologize. I'm new here, so can you clarify a few things for me?
- What is a zombie thread?
- If I revived a zombie thread, how were you and Don notified about that?
- What are the ranges that you referred to? Does the C-range refer to 500cc engines? What is the range for a T120R?
- Are there ways to post private messages? I would have written directly to Mr. Whatley if the "Send Private Message" function worked for me.
But when I try to use that, the forum says that "Private messages are disabled". If that is the case, why is the option to send a private message still displayed?

Thank you in advance for your patience. I'll get better at this.

Kind Regards,
Brian

Hi Brian,

Welcome to the Forum.


No need to apologise and not really wrong, just not really helpful for you and a bit confusing for others.


General internet forum slang for a very old thread that's suddenly revived with (a) new post(s).


No notification, I just happened to recognise "Matthew in TO" when the thread appeared on the first page of the index; when I looked at the thread, it seemed an odd question for Matthew to ask now; when I looked at the last post before your first, it was dated 2006 ...


I find "C-range" a handy short-hand as the range encompassed both 350 and 500 'unit' (gearbox in the same castings as the crankcase) engined models.

Your T120R was officially 'B-range' (singles were 'A-range') but 'B-range' isn't such a useful short-hand as it encompasses not only unit 650's and 750's but also 500 and 650 pre-units (gearbox separate from crankcase) - just after WW2, the pre-unit 650 was basically an enlargement of the pre-WW2 500 twin.


If, by 'the "Send Private Message" function', you mean the link that drops down when you click on a user's name to the left of his or her posts, one reason that link might not work is if you have more than the limit of pm's in your message box - the limit depends on your "Membership Type" but, even if you're a "Free Member", you're allowed up to store up to ten pm's.

To check your pm box, if you look towards the top of each BritBike webpage, under the banner, adverts., menu, path, etc. is a line that starts "Forums", "My Stuff", "User List", etc.? If you click on "My Stuff", "Private Messages" is listed in the drop-down, click on that to go to your pm box. You can also post pm's from the pm box webpage.

If you can't see an obvious problem, if you go to the first Forum webpage - the one that lists all the forums - and scroll down a short way, you should see, "BritBike FAQ Forum". Post a message there addressed to "Morgan aka Admin".


No worries, we all started in the same place.

Hth.

Regards,

zombie thread - "General internet forum slang for a very old thread that's suddenly revived with (a) new post(s)." - What Stuart forgot to add is they are hard to kill also but fortunately do not eat brains.
"even if you're a "Free member", you're allowed up to store up to ten pm's." - Actually, when your quota hits 8/10 you cannot receive any more messages and they get a "mailbox full" message. No idea why.
Copper or aluminum washers only work with flat parallel surfaces. If it does not seal with 5 ft-lbs it will not seal with more. Either there is a scratch in the surface or the surfaces are not parallel.Generally you can get away with it if you coat the washer with Loctite Gasket Eliminator or similar anerobic sealant and let it sit a day to harden.
McMaster is a good source for foot-and-finger or metric O-rings and you will probably pay almost the same at a hardware store but have quite a few more.
You should have a caliper to measure things. A pitch gauge would be handy. I think most threads on yours ('69) are Whitworth or BSF (BA or Cycle on small threads) but Stuart or somebody will know. If a unified (american) fine nut or bolt starts but then locks up it probably is BSF If a couse fits but feels loose it probably is Whitworth.

Hi Brian,


The term "Whitworth" as Dave has used it is confusing, particularly on your bike.

Americans have a terrible habit of describing any non-American threadform as "Whitworth". However, it's particularly unhelpful with your bike because Whitworth is a particular threadform (BSW = British Standard Whitworth) but I can't think of any components on your bike that use it.

Nevertheless, your bike does have a mixture of Unified and other British Standard thread forms:-

. most components have UNF or UNC threads, but never assume it or you will come unstuck; there are also UNEF (Unified Extra Fine) and UNCP (Unified Constant Pitch), and particularly the oil pressure switch and timing cover are either 1/8"NPT (National Pipe Tapered) or 1/8"NPS (National Pipe Straight);

. Dave has mentioned BSF - British Standard Fine - but some components have BSC - British Standard Cycle (aka "CEI" and just "Cycle");

. almost all Fasteners smaller than 1/4" outside diameter are BA - British Association - but, just to catch you when you get confident, the odd tiny one is UNC - e.g. the screws that fasten the front brake gauze to the brake plate air scoop;

. the fuel taps are 1/4"BSP (British Standard Pipe).

You might or might not need sets of wrenches and sockets to fit British Standard Fasteners. E.g. if necessary, I could get away without on my '69 T100 - the only hex. Fasteners I can't replace with UNF/UNC are the 3/8" o.d. bolts and studs through the rocker-boxes and cylinder head into the cylinder block, but one of my socket sets has a 19/32"AF socket, which is a good fit on those hexs. :bigt

If you do decide to buy British Standard wrenches and/or sockets, be aware:-

. As I say, because so many of your countrymen insist on calling them "Whitworth", you'll get a lot more hits searching the www for "Whitworth" wrenches and/or sockets than searching for "british standard".

. British Standard tools are marked by the fastener major diameter, not the AF measurement like Unified and metric wrenches/sockets. I.e. while, say, a 3/8"UNF bolt will have a 9/16"AF hex. head and whatever tool to fit will be marked "9/16", any tool to fit a 3/8"BSC or 3/8"BSF bolt will be marked "3/8 BS" (unfortunate abbreviation ) but will still be a similar overall size to the aforementioned 9/16"AF wrench or socket (3/8"BS hex. is 0.6"AF).

, Another reason not to use "Whitworth" except correctly for Whitworth threads is British Standard tools are also likely to be marked with another measurement and "W" - e.g. a "3/8 BS" wrench or socket is likely also to have "5/16 W" - because old original Whitworth Fasteners have a one-size-bigger hex. for a given thread diameter.

. Digressing ... the reason is historical - Whitworth is named after Sir Joseph Whitworth, who first standardised the dimensions of British Fasteners for manufacturing in 1841. Wind forward to the early 20th century and the introduction of BSF (British Standard Fine) thread - so-called because Whitworth threads are coarse (and therefore easily loosened by vibration ) - to help acceptance, the same hex. sizes as Whitworth were used but, at the time to save material, a smaller hex. size is used for each thread diameter.

. However, new Whitworth-thread Fasteners are now so uncommon (old machinery preservation is about the only requirement) that any tend to have BSC/BSF hex. sizes ... negating the need for different markings on tools ... and further confusing newbies ...


+1.


Ime it's "should have" too.

Also bookmark http://stainlessbits.com/link12.html - you can look up almost all fastener diameters, threads and lengths using Triumph part numbers from the parts book. :bigt

Hth?

Regards,

Not ANY non-american thread, British threads of Whitworth form. There are many other non-american threads that are not Whitworth. Although you detest using the name Whitworth for these threads, as you mentioned doing a search using Whitworth will get a lot more hits than British Standard. The guide that I have (Zeus Precision Charts Ltd., British Channel Islands) uses BSF for the fine thread and just "Whitworth" for the coarse.
What I think you missed though is the Whitworth thread form is 55 degree with rounded crests and valleys which is why a 1/4"-20 UNC nut on BSW bolt will feel loose but still fit. 1/4" through 2" in both BSW and UNC have the same TPI except 1/2".
A 1/4 BSF is 26 TPI so a UNC 1/4-28 will not fit. All the BSF have a different TPI than the UNF.
"I think ... but Stuart or somebody will know." - I stated this because I am not versed in the older twins. But I should ask, what about the inspection caps? On a triple those are Whitworth thread form, twins also?

Hi Dave,


Nope, it's irrelevant on Brian's bike. As Brian admitted, and you can see from his post count, he's a newbie. What's the point of going into detail about threads that aren't anywhere on his bike?

Likely Brian won't even find any BSF threads on his bike. The only British Standard threads that he'll definitely find are Cycle - which aren't "Whitworth form" ... and BSP on the fuel taps - which are.

If Brian posts he intends to make new inspection caps, that's better the place to discuss the peculiarities of their thread? I know the later of my two T160's has the countersinks on the chaincase machined to 55 degrees rather than UNC's 60 degrees but, again, of what relevance would that be in posts about a '69 650?


The only reason I mentioned "Whitworth" specifically in relation to searching for tools is it's been posted before that's the term commonly applied in the US, where Brian and you are. It doesn't apply everywhere else in the world, nor will it matter if Brian finds also that the only British Standard Fasteners he needs any sort of 'special' tool for are the head bolts.

Hth.

Regards,

I hope Brian finds the lecture about threads useful in solving his chain oiler problem!

Stuart, you are funny. You say it is irrelevant about me explaining why a Whitworth thread form differs from UNC but you went into depth explaining the head size, tools and history of Whitworth threads.
Even though I said "I think ..." and referred him to you, you still insist that I am positive there are Whitworth (BSW to you) threads on his bike and then you say they are no where on it except, of course, the inspection caps.
Tiger's point is well taken.
If you look at Brian's posts, the only thread he asked about were "zombies".
Unified flat head screws are 82 deg.

Brian, this is just the usual banter you get on forums. Do not take this negatively about posting questions.

Mmmm ... no-one mentioned any other threads 'til post #708861 ...

Hth.

Regards,