The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: lukasgrech on May 14, 2014, 01:20:26 PM
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Couple of oil questions (for my '79 R65):
1. My engine oil level is coming close to the MIN level, so it's time for a fill up, however as this is my first oil refill on this bike, I don't know what oil the PO used. -- Should I drain the entire sump and refill with completely fresh oil?
2. Which oil grade should I use? (My first oil change, I do beg your pardon for my ignorance).
Manuals and their suggestions don't quite line up with what's on the market. Will a 10W30 oil do? Do oils with 'Racing' in their name qualify for use?
3. Discovered a small pool of golden coloured oil under the bike (been standing for 3 days). Oil is dripping from the nut at the bottom of the gearbox (you can kindof make out a drop forming on the nut in the photo). The location makes me think it's gearbox oil, but the look and touch of it seems more like engine oil - although no signs of leakage from the sump drain plug.
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi1349.photobucket.com%2Falbums%2Fp759%2FLukas_Grech%2F2014-05-14181355_zps869de75a.jpg&hash=682c034ab60b22d248f5035333af716e27abdeb6) (http://s1349.photobucket.com/user/Lukas_Grech/media/2014-05-14181355_zps869de75a.jpg.html)
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The owner's manual (one on this site, somewhere) shows the right oil viscosities to use for different temperature ranges. I don't know which is right for you, probably 10W-40 or 20W-50. Ignore the term "racing."
How long/how many miles since the oil was last changed? It's probably time for that, and you will probably want to change the filter as well. Look for posts on this site on the filter/shim/O-ring, as it's a little complicated. It may be time to change the oils in the tranny, drive shaft, and final drive, too.
That oil in the picture is probably not coming from the gearbox cover, but you will have to clean things up under there pretty dry to be able to tell where it is coming from. It seems like oil blows all over under there if there is a leak.
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You should be able to tell if the oil is from the gearbox or engine by the difference in smell with gear oil usually having a distinctive odour. Likely culprit is the neutral switch visible in your pic.
Whether you top up or change the oil don't fill above half way between min and max marks on the dipstick. This is to maintain some air space in the sump which will minimise oil loss via the engine breather. This is a generally accepted policy across all airheads and is particularly applicable to a 79 as it has a slightly shallow sump than the later models.
If you are going to top up I wouldn't worry too much about what to put in. What oil have you got to hand if any ? I'm a fan of 10w40 but 10w 30 is definitely too thin for year round use even in our climate.
The oil chart in the riders handbook gives BMW's view in 1979 which is still going to be fine as far as protecting the engine. They did however through a series of service bulletins provide revised guidance over the years as oil specifications changed. Generally there was a move to accept the use of thinner oils like 10W40 at higher ambient temperatures. This chart issued in 1995 is the latest one definitely applicable to airheads.
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Thanks for the replies and the pointers.
I don't have any oil to hand at the moment.
The leaked oil doesn't have any distinctive smell.
Looking for more than a few minutes, the leak is quite clearly coming from the swingarm to gearbox rubber boot.
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi1349.photobucket.com%2Falbums%2Fp759%2FLukas_Grech%2F2014-05-14202900_zps935d6b96.jpg&hash=a9915caae89516311828ab862138c8ba8bf72c11) (http://s1349.photobucket.com/user/Lukas_Grech/media/2014-05-14202900_zps935d6b96.jpg.html)
The boot is horrendously swollen in two spots, almost certainly porous there and the zip-tie has come off.
From what I know about the replacement procedure for this, this is not a one man, standard-tools job. Any advice?
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It does not get terribly cold in Texas so I maintain my three Airheads with Castrol 20W50 engine oil that meets the BMW's need for an SJ / MA2 spec oil. Little bit of zinc needed to keep those flat tappets and cam happy.
In your neighborhood's winter, you might consider the 12W40.
I run dino / mineral oil. The thinner and slicker synthetics often create oil leaks by getting past the OEM seals in the engine and drive train.
Suggest you change ALL fluids -engine, trans, driveshaft and final drive- to set your maintenance benchmark. Be sure to add a new oil filter, shim and o-ring to the job.
As to that zip tie on the diff's boot... that may very well be your leak source. There should be the proper metal clamps on both ends. What occurs with a Zip is a small, unclinched spot right where the strap passes through the locking portion. You'll never get it snug enough to stop weeps, seeps n' leaks.
BTW, gear oil stinks. Easy identifier.
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Cheers.
Does 'part-synthetic' count as mineral oil?
I plan on doing an all-fluid change asap.
Do you think I should go through the entire boot change, the surface of those blisters seems quite cracked, or should I just try to change the zip tie to the proper metal clamp?
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... Does 'part-synthetic' count as mineral oil?
Only partly so. [smiley=whistling.gif]
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Do you think I should go through the entire boot change, the surface of those blisters seems quite cracked, or should I just try to change the zip tie to the proper metal clamp?
Changing the driveshaft boot can be a life changing event. ;) No, not really, but it is necessary to detach the swing arm by removing the bearing pins and then separate the u-joint from the trans drive flange.
Properly orienting the new boot and getting it onto the seating areas -front and rear- usually results in several choice words and perhaps a wee bit o' blood. Then getting the metal bands to meet and threads engaged, well, more words.
New u-joint bolts -the short versions- are installed without washers and should be torqued as close to spec as you can get 'em.
Suggest you invest in a shop manual. Haynes or Clymer or both; as each manual has a few errors that the other can help explain away. Study the entire process and take your time with the boot install. Accidentally poking a hole in the new boot with a small screwdriver is an unhappy event.
Try the correct metal clamp if you wish. That's a quick way to discover if there's a hidden tear in the old boot or the zip tie was just a quick qhetto fix that didn't work.
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Mineral oils are a bitch to track down in town. Might have to order it online.
I will try the quick fix with the metal clamp and re-fill all the fluids and see if the leakage stops - I would like to avoid teaching myself new words, for the moment :)
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Does 'part-synthetic' count as mineral oil?
I've being running engine oil with with a 30 % synthetic content (and that's a lot more than some so called semi-synthetic oils) without noticing any problems with seals leaking.
By way of an experiment for my next change before winter I have some full synthetic to try. It will either stay in the engine or it won't and I'll be sure to report back which it is.
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Thanks Barry. Think I'll give this a try: http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_263777_langId_-1_categoryId_165507
From look and feel alone, the oil already in the engine doesn't seem to be very viscose anyway, so looks like I'll be ok with that choice.
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That looks like good stuff. Castrol describe it as part synthetic and it has the SJ rating that Monte mentioned.
Dear though ! Just as well you only need 2L for an oil change.
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You should be able to buy 5 litres of usable semi synth in a supermarket or down BandQ. You do not need to use motor cycle oil as you do not have a wet clutch. And your engine only revs to 7000rpm.
The oil is only going to be in there form 5000 miles. Halfords is really over pricing its oil.
Save yourself a fortune...Or in this case get 2 oil changes for half the price of one from Halfords.
cheers
Rev Light
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I buy my oil in bulk when it's on offer. When I had more cars at home I bought it in 25L drums at £2-£3 litre.
For UK users http://www.eurocarparts.com/car-engine-oils have some good deals and do free delivery.
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Thanks for the oil tips, I'll have a look around before I spend that much money on half an oil change!
And now, digging deeper...
1. Rear bevel drive oil - practically empty and coffee with cream coloured. I believe the level is meant to be up to the bottom of the filler thread?
2. Drive shaft oil - NONE. Checked with a dipping stick and seems to be dry.
3. Gear box oil - Came spewing out when I opened the filler plug. Again, I'm given to understand that the level here should be just at the lower point of the filler plug.
Re. colour of bevel box oil, according to Snowbum's site, this means that water could be leaking in via speedometer boot (quite likely - rubber looks beat and now grease or silicone anywhere - will replace and seal up). However, he is referring to driveshaft oil. I am not yet familiar with the details of the construction of the final drive assembly, but all of this seems to me like things are leaking into one another, and leaking away too, since the levels are extremely low.
More worrying is that the PO had oil added to drive shaft and to bevel box, about 300 miles ago.
And finally,
4. The oil that is seeping from the swingarm rubber boot is indeed gear oil - it does not smell as strongly I thought it would, but a smell test comparing it to engine oil leads me to believe it is indeed gear oil. The large excess of oil in the gearbox could explain why this is ending up leaking from the inside of the boot out.
Where the hell do I start? :D
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Good job you checked !
Rear bevel drive has had water in it for sure which is not so common as else where as the only way for water to get in is through the vent on top. Maybe it was jet washed.
It could have been worse in that water in the gearbox is even less desirable and more expensive. The speedo drive boot is the culprit for water in the gearbox and the swinging arm rubber boot will let it in to the drive shaft oil.
Oil migration between the transmission parts is not that uncommon so I wouldn't panic too much yet. I'd start by just refilling with the correct quantities of clean oil and flush out again after a few miles. Levels are as you say. 800cc should get you to the lower edge of the fill hole on the gearbox. Final drive takes 250cc to the bottom of the filler threads. The Drive shaft is supposed to take 150cc but it's generally accepted that this is too much and if you put that in it will usually just migrate else where. Drain well and put in a measured 100cc or 120cc at the very most and it will usually be fine. Of the 3, the gear box oil level is most critical. The final drive and drive shaft will probably come to no harm with less oil then specified.
Maybe oil will still migrate and you'll need new seals and maybe it won't. When I first got my bike the drive shaft oil had finished up in the final drive but after my first round of oil changes to the correct levels it has stayed put.
80W90 GL5 is what you need. Semi synthetic has some benefits but perhaps not for the first flush and not while the seals might be in question.
BTW how much fuzz was on the magnetic drain plugs ?
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Lukas8165,
Chap, you are only 30 odd miles away. How about meeting up for a 'Southern Softy Shandy' and I'll do my best to get yourself educated proper like.
I am at the end of the A419 in the much maligned Swindon Town.
Cheers
Steve Hawkins
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Begin by draining all fluid reservoirs. To save that expensive lubricant, some folks will flush a bit of kerosene and drain thoroughly. The milky oil indicates water being emulsified with the oil. Thats not good for bearings or steel shafts, etc.
I do not trust the fill level plugs for their so-called accuracy. I much prefer to add the manuals indicated amounts; except I do run the gearboxes on all three of my Airheads with a gear oil indication at halfway twix max and add. helps reduce blowby, drips and a messy bike.
Da Snowbum states that the driveshaft can safely run will much less gear oil than the manual specs.
An overfilled gearbox could be the culprit as could be a failed shaft seal allowing the oil to pass into the boot.
Water in the final drive could enter via the "acorn nut" breather on top of the case if a PO had ridden in deep water or did frequent hi-pressure washings. Don't do that. If gear oil is passing beyond a seal, then water lwaked into the boot might also migrate to the final drive.
Your work is laid out for you, Lukas. Drain everything. Flush if you choose or use an eco lightweight oil as a flushing agent. Refill all with the manual's specified amounts of oil types and weights.
Replace that rubber speedo cable boot, too.
Sing out should you have additional questions. Good luck.
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Thanks for the extensive help and all the info everyone, very much appreciated!
An oily weekend it shall be!
I haven't undone the drain plugs, but I'll keep an eye on how much metal fuzz is stuck.
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Lukas8165,
Chap, you are only 30 odd miles away. How about meeting up for a 'Southern Softy Shandy' and I'll do my best to get yourself educated proper like.
I am at the end of the A419 in the much maligned Swindon Town.
Cheers
Steve Hawkins
Steve,
Would love to meet up - my oil situation and British weather permitting, hopefully we can do so soon.
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Monte, when you say a failed seal, is that likely to be the output shaft oil seal?
How much of an adventure is it to replace that?
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[/quote]
I've being running engine oil with with a 30 % synthetic content (and that's a lot more than some so called semi-synthetic oils) without noticing any problems with seals leaking. [/quote]
Not a specific reply to you Barry, more a general comment.
There is nothing wrong with the seals, they are in main, catalog single and double lipped seals that are well spec'd for the task and provide years of trouble free service.
There is none of the nonsens of earlier generaion engines and gearboxes involving oil soaked felt or graphite impregnated sisal to try and replace periodically.
Yet there is a mythology that BMW /5/6/7 engines and gearboxes are prone to leaks.
Bollocks I say.
What you do see is that the basic engineering of the BMW engine and gearbox is so fundamentally sound that engine cases and gearboxes are out there from the late 70's with seals that have never been replaced and which are only now getting a bit "leaky".
Don't know of too many car engines that are still oil tight after 35 to 40 years.
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Monte, when you say a failed seal, is that likely to be the output shaft oil seal?
How much of an adventure is it to replace that?
Prior to getting all ramped up about possible extensive repairs, drain all fluids and refill as discussed. I hope you have a shop manual in your tool box. There's also a downloadable pdf Owners Manual for the 81-84 R65s in the R65 Technical FAQS/procedures section. Check page two and scroll down to find it. The lubricant quantities should be the same for your model. Without a benchmark to go by, you'll be shootin' in the dark. Clean up the bike and watch for the Three Dwarfs... Weepy, Seepy and Leaky.
I can almost guarantee you that the improperly installed boot is your primary issue. Remember, air currents pushing oil drips to strange places have caused more money than necessary to be thrown at motorcycles.
Also, acquaint yourself with The Snowbum. Rather long-winded and very wordy but an Airhead treasure of technical knowledge. Check him out for details regarding your concerns.
http://bmwmotorcycletech.info/technical-articles-list.htm
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Lukas,
You ideally need the 79 riders manual as it has the correct fill volume of 250cc for the final drive. 81 on models take 350cc and the fill/level plug arrangement is different. Also engine sump volume is different. We 79'ers are very much in the minority so it's helpful to know the host of subtle differences between the models. I've attached a chart which covers most of them.
PM me and I'll e-mail you a copy of the 79 riders manual by return.
You'll need a proper workshop manual for the seals but I agree with Tony. Mine will only get done when they need it. Still have all the original 35 year old seals and no drips anywhere. A little misting around the nether regions and a trace of oil on the shelf under the gearbox but who hasn't. Consumption between changes is near zero.
Don't know the history of your bike but if it has been laid up for a time don't judge the seals until it's had some use.
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There is a pdf in the Tech/FAQ s the riders manual for 81 ? I posted it but mine is a 79? i use Castrol Classic oil they have it on offer at Maccess if you have one near you.
Lou
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Lou,
You have the 79 manual in PDF somewhere as you sent me a copy. Size is the reason it's not posted here. At 5MB it's too big but OK as an e-mail attachment.
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Lou,
You have the 79 manual in PDF somewhere as you sent me a copy. Size is the reason it's not posted here. At 5MB it's too big but OK as an e-mail attachment.
I think I saved it on my Seagate Hard drive as this is a new lap top and I saved all my old files.... if anyone is desperate for it I will dig it out but I think the oil specs would be the same for all the R65,s anyway.
Lou
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Lou,
I've already sent it to Lukas so he's OK.
Oil specs will be the same but it will provide the correct fill volumes for final drive and sump which are different to the later models.
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Right.
All fluids changed.
To re-fit the boot properly I had to take out the battery and battery box, this gave me better visibility of the boot, which is in absolutely horrible shape. It's doing precious little in terms of keeping oil in, although it still does enough of a good job keeping dirt and gravel out of the driveshaft.
The driveshaft oil drain plug must have been over-tightened at some point, as it does not unscrew, turning it clockwise or anti-clockwise both end up in it tightening up and stopping.
I added 100cc of driveshaft oil, and then checked the level with a dip stick as per the manual instructions, and found it to be at about 2mm height from the top of the driveshaft, which leads me to believe that it was running on very little oil beforehand.
At some point I'll have to replace the rubber boot, and since that will involve quite a dismantling, I'll deal with the driveshaft oil drain then.
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... The driveshaft oil drain plug must have been over-tightened at some point, as it does not unscrew, turning it clockwise or anti-clockwise both end up in it tightening up and stopping.
Odd. Is it leaking or is it oil tight?
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It is leaking, quite slowly, but it is noticeable
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No problems, only opportunities...
So after approx 150miles of riding this weekend, I had a look at the oil levels again:
Gearbox has not lost any oil - good.
Driveshaft is practically dry again (stripped thread/highly porous rubber boot spewing oil) - bad
Bevel box oil, reduced to what it was before I drained and re-filled, I'd say it's lost about half the oil again - bad?
1. What damage am I risking, riding the bike with such low driveshaft and bevel box oil levels?
2. The driveshaft leaks are pretty obvious, but the bevel box? Drain plug is installed correctly, and I don't see how it could leak that much oil all the way up the driveshaft through the boot, even if a gasket or seal had blown
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Hello !
Remove he rear wheel and see if the drum is wet or not. If not, maybe the rear drive is leaking oil into the swing arm where it is lost by the leaks you already noticed ....
If the rear drive oil is transferred into the swing arm, you're not lucky because this lip seal is not easy to change without special tooling. (from BMW or custom made.)
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Yep I feared that's what might be happening. I'll have to do some disassembling and investigate further.
Thanks!
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My thought exactly... I am lucky enough to have access to motor oil from my fiends garage and I have no leak problems after 50K on a 1982 R65T. Modern oil I believe is far superior but i would change more often just for peace of mind, oh and I like getting my hands dirty.
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If you are noticing, and can confirm, oil loss from the final drive, there are a couple items to check:
1) The rear brake cam should have a couple small o-rings that seal the cam-to-case contact. The brake cam is steel and there is no bearing of any kind for the shaft to bear on; just the aluminum final drive case. Look for weeps n' seeps at the rear brake arm attach location.
2) Beneath the Cardan cover -the casting where the drive splines pass through- is a large oil seal that bears on the spline shaft. If it has become overheated, split or abused with dirty lube, it can leak into the final drive and then out the bottom.
Both items are fairly easy to check and/or replace.
Chasing drips can be challenging. Dusting with baby powder can help... sometimes. ::)
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So I did a very thorough job of chasing the oil drips and I can confirm that the only leaks are from the torn up rubber boot, and from the driveshaft drain.
The bevel box has stopped leaking and the oil seems to have settled at that low level. To me, this rules out any possible leakages from around the bevel box (drain/seals etc.) as otherwise it would continue leaking until it was empty.
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The bevel box will get by with less than the normal level but how much less do you have ? You could drain it out, measure the volume and put it back again.
Remembering this is a 79, the potential brake cam leakage is not applicable. To explain for Lukas, on the 81- on models the bore for the brake cam shaft is open to the final drive oil so needs O ring seals on the shaft to keep the oil in and they can still leak. BMW increased the number of O rings from 2 to 4 in an attempt to improve sealing.
On the 78 - 80 models it's a straight through closed bore with no possibility of final drive oil getting to the shaft which is only lubricated with grease on assembly. There is a felt washer on the inside to keep the grease in and that's it.
If you have the rear wheel off for any reason it's worth removing the brake cam to clean up and lubricate the shaft as it's not a scheduled service item and so may never have been done from new. Mine hadn't.
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So I finally got around to give the bike some attention - toothbrush and elbow grease cleaning, I wanted to keep water distribution to a minimum.
I measured the bevel box oil, and there was about 100cc in it, it has stayed pretty stable at this level for the past few rides, I did a visual check from the filler plug after a few of the rides, and the level didn't seem to be moving. I refilled with about 150cc, cleaned up the bevel box and dusted with baby powder so that any leaks will hopefully be visible after some use.
I will eventually come to a point where I'll have to remove the driveshaft, swingarm, rear wheel etc, in order to replace the rubber boot. At that point I intend on giving the whole assembly a bit of an overhaul - lube the brake cam shaft, repair the driveshaft oil drain (helicoil?) and make sure everything is sealed up. Until then, I will have to make do with the occasional oil drip cleanup, and avoid riding too much in the rain.. not such an easy task in the UK!
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Can anybody explain the bevel box seal replacement procedure please!
Mine is leaking bad after changing the bevel box to a new used one as my splines were totaled. Reducing the volume of oil did eliminate the drips when bike is stationary but when I get on the road and rev hard (contrary to Steve Hawkins's reccommendation), the whole tire will be sprayed. Easy riding will not do the trick.
Leak comes from the centre of the bevel box output seal (the large diameter one) and finds its way down between the bevel box and wheel.
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The large seal around the drive spline to the rear wheel that Arvo has a problem with is considerably easier to replace than the seal which is on the input (driveshaft) end of the cardan drive unit. Somewhere here we had a thread with pics on this. Maybe Monte wrote it up - it is in this thread -
http://www.bmwr65.org/cgi-bin/yabb2/YaBB.pl?num=1394488408/12#12
Along with the seal around the output splines, you should/must also replace the thin paper gasket that goes between the inner cover and the main housing of the cardan drive. monte's write up and pics in this thread should help you through it. If you don't drink beer or other beverages from aluminum cans, you could also just get a good length of electrical tape or duct tape to wrap several times around the output splines to protect the inner surface of the output seal as you slide it into position.
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One thing that isn't in Monti's write up, is there are two small threaded holes in the cover, they are for a small bolt / screw to thread into, when the bolt contacts the case, it starts pushing the cover off .
You can see these in the third picture, but I beleive the R65 cover has these bolts in a bit not in tabs on the edge .
You ca nheat the cover up and cool the crown gear and it makes for an easier reassembly .
Also replace the two o-rings 0n the brake cam shaft .
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Thanks for the link. That info is useful. It seemed a far more complex chore before knowing these tips. I do have all the required tools/seals to get the job done but I have to add this into the "to do list".
I got my bike MOT-d and registered 3 days ago and after lots of years she is back on the road. I really do not want to take any jobs on at the moment as riding her is a blessing at the moment. She is my daily commuter to work and she is running strong with a occasional period ;) I can cope with that for a week or two I guess.
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Hi there, noticed you are in the UK - Try B&Q 20/50 just over £10 and a quality oil, my friend a Chemist at BP grangemouth checked it out and thinks it has all the properties requires for older bikes esspecially Air-cooled twins...
You should be able to tell if the oil is from the gearbox or engine by the difference in smell with gear oil usually having a distinctive odour. Likely culprit is the neutral switch visible in your pic.
Whether you top up or change the oil don't fill above half way between min and max marks on the dipstick. This is to maintain some air space in the sump which will minimise oil loss via the engine breather. This is a generally accepted policy across all airheads and is particularly applicable to a 79 as it has a slightly shallow sump than the later models.
If you are going to top up I wouldn't worry too much about what to put in. What oil have you got to hand if any ? I'm a fan of 10w40 but 10w 30 is definitely too thin for year round use even in our climate.
The oil chart in the riders handbook gives BMW's view in 1979 which is still going to be fine as far as protecting the engine. They did however through a series of service bulletins provide revised guidance over the years as oil specifications changed. Generally there was a move to accept the use of thinner oils like 10W40 at higher ambient temperatures. This chart issued in 1995 is the latest one definitely applicable to airheads.
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Try B&Q 20/50 just over £10 and a quality oil, my friend a Chemist at BP grangemouth checked it out and thinks it has all the properties requires for older bikes esspecially Air-cooled twins...
It would be interesting to know who makes their oil. There are only so many oil companies that produce lubricant oil. It's a similar senario to "BMW oil" which used to be Spectro and is now Castrol. I suspect you can write a specification for oil and have any oil company make it.
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Had not thought of B&Q. I'll give it a try next. Cheers Andrew