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How NOT to Design A Fuel Pump Connection ALL R12s

I confirmed that the controller on my bike (the one that started this thread) is dead. No voltage output at its connector now. Cut the connector off, made a jumper, plugged it into the front accessory outlet (rated at 10A on the 08RT, it runs the 7A pump fine).
Bike starts and runs normally with the jumper, pump can be heard to run continuously as expected. The jumper, of course, has to be unplugged when stopped or ot will kill the battery pretty fast with that 7A draw.

Going by a dealer tomorrow to get a replacement and spare. Will expect to have the dead one covered on warranty and will report on that- after all I saved them the cost of a tow and dealer repair.

At least a jumper should be in your roadside parts kit- its cheap insurance. Of course, you have know how to pull the left cover (T-25 screws) and the controller (T-20 screws) to employ the jumper and you have to know the controller is the problem in the first place.
Some of them have been reported to fail from heat but if I saw water in the well, GS-911 available to confirm the matching 10198 code or not, I'd be reaching for that jumper if my bike went dead (and I didn't have an EWS error or dead battery)

Despite the fins on the controller, no internal parts contact the housing to eliminate heat and remember that 7A or about 90W pass through it. Instead, the parts are sunk into insulating silicon rubber that doesn't even keep water out. On mine, it has shrunk away from the wires and the edge and there were a couple very slightly corroded connections on the board so it is a bit hard to tell if mine died from water or heat.
 
A good quick test is to spray some starting fluid into the intake snorkel. If the bike fires up for a second, you know you have a fuel problem. Of course, that could be the pump, the board, the wires, the injectors, etc., but it at least quickly narrows it down to a fuel problem and it doesn't take long to nail it down. 99% chance it is that driver board, too.
 
How about cleaning off the surface around the controller and applying a bead of RTV to seal it up properly? One could also cover the FPC with copper foil to dissipate heat.
 
That's pretty much what I did to mine. I think it is very water tight now. I didn't mess with the cooling aspect. It has cooling fins on it and there's only so much a guy can do. Hopefully the heat sink and fins will do the job.

The BMW dealer told me this board regulates how much current goes to the fuel pump and that is how it modulates fuel pressure to the injectors. Instead of using a pressure regulator with a fuel return line. That is why I call this the "fuel pressure regulator" although "driver board" is more correct.
 
I read this stuff praying I didn't make a mistake purchasing my R1200RT. This stuff shouldn't be going on. I had a Kawasaki concours 1000 put over 62,000 miles on it with no break downs, my Honda ST 1300 33,000 miles no problems. I stopped toting my tool bag on trips because the were so dependable. Now it looks like I might start toting it again. If I have to carry spares to make a trip I won't be owning this thing for long. Thanks for the information. I'm going to make up a jumper wire just in case.
 
The BMW dealer told me this board regulates how much current goes to the fuel pump and that is how it modulates fuel pressure to the injectors. Instead of using a pressure regulator with a fuel return line. That is why I call this the "fuel pressure regulator" although "driver board" is more correct.

FWIW, That would be good information if it was true but it's not.
The RT does have a fuel pressure regulator.
BMW is varying the pump flow, this will not change the pressure (it will still be regulator pressure) They are varying the volume by varying the flow.

You might have noticed a vacuum hose between the intake and pressure regulator on FI systems, this will vary the pressure. They lower the pressure when high manifold vacuum is present for the simple reason it's easy to spray fuel into a negative pressure. When manifold vacuum drops off it requires more fuel pressure. This style regulator usually changed the pressure by a max of 5PSI

I don't know BMW's reason for using electronics when a mechanical system worked fine, it must give them better control or something like that.

http://www.maxbmwmotorcycles.com/fiche/DiagramsMain.aspx?vid=51560&rnd=03192010 Look at fuel supply
 
I read this stuff praying I didn't make a mistake purchasing my R1200RT. This stuff shouldn't be going on.
You know, it's easy to get a distorted perspective from reading all the posts in the forum about engineering, design and manufacturing problems. I mean, few people log on to post about how great it is that something hasn't broken. Instead, people tend to post about problems that they've encountered, so it sometimes seems like BMWs are overpriced lemons waiting to break down at any moment, when that really just isn't the case.

BMW bikes are some pretty complicated pieces of advanced engineering, and occasional problems are inevitable. They're certainly not perfect, various breakdowns occur and less-than-perfect engineering happens, but all in all, they're mostly very reliable bikes. I agree that BMW ought to redouble their efforts on a few commonly mentioned and perceived inadequacies, but still, they're pretty decent and dependable motorcycles.
 
So which bikes are outfitted with the screw cap and gasket, items 9 and 10 or was this a cost-cutting measure? -

B0004727.png
 
All of them. It is not what you think it is. The gasket goes on the inside of the tank, the screw cap is the metal bit that holds the fuel pump unit to the tank. It does NOT "cover" the connections to the fuel pump. 6 is the gasket, 4 is the screw cap.

K25_02_R16009c_small.jpg

Some bikes have a plastic cover. The cover has slotted vents and will not keep water out is that is what you are thinking.
 
Dead Controller Warrantied

Stopped by MD's big BMW dealer yesterday on my way to a meeting in Baltimore.

Their service dept made the warranty claim and BMW rapidly agreed. So I've got 1new controller on BMW and second one to carry as a spare on me.

Marchymans diagram and explanation are right on. There is no way to cover the well on an RT anyway- there 2 hoses and 2 electrical connections that come out of the top. An improvised duct tape shiled might deter road spray water but might also trap some heat around the controller.

The current replacement controller is black powder coated so less susceptible to corrosion on the housing.

Re adding a heat sink to it- that's a no go. Problem is NOT the controller housing design but that the internal parts of the controller that need heat sinking do not even contact the housing. Instead, they are encased in black silicon rubber, a heat insulator. Won't matter what you do to improve heat conductivity of the housing...

As far as the "BMW bashing" comment-
I've made most of living either designing or proving processes to manufacture items that human lives depend on where a screwup might literally kill somebody quickly. I admit to little or no patience with stupid engineering and have many times in my professional life bluntly called out inept or lazy engineers and told them to get their s**t together. German automotive firms have a long and well established history of poor design of electric components for reasons I don't fully understand but I think some of it springs from the very rigorous in service inspection systems that make keeping older vehicles on the road cost prohibitive.
So I don't think they get much durability info out of their domestic market. But whatever the reason, stupid is stupid and there's no excuse for a controller design this poor. This is a "designed in" failure, not a random failure of a correctly engineered system.
I applaud and appreciate good design and there is certainly much on my 08 RT to applaud- I am a total fan of making the bike more like a car with electronic modules (the BMS-K and ZFE) and the ease of troubleshooting that goes with that. Many of the systems and parts are exemplary- for example the large dual discs in front,stainless brake lines and the whole brake system on the 08, weight saving plastic and alloys, weathertight and large cases, a robust engine/trans/clutch system- the very heart of the bike, better than average headlights, etc.
There is a long list of good to great stuff on BMWs.

But some electrical failures (or an FD) can leave you stranded unless you're competent, have tools and it is bypassable. Some electrical things aren't bypassable (EWS ring for example). German firms in general and BMW in particular need to do a much better job with electrical parts. Go find the link for the continually increasing number of controller failures being reported on GS models in the UK that proves attempts to address this item in the marketplace are not successfully reducing on road failures experienced by owners.

I'll contrast BMW behavior with a previous experience with a Kawasaki. In the mid 1970s I had a Kawasaki enduro with a stainless front fender. a few bikes had 1 of several fender to bracket welds fail- not many and none at my local dealership. I got an extremely apologetic letter from Kawasaki in the mail along with a free stainless part and instructions how to bolt it on so fender failure could never happen on mine. There would have been no danger had that weld failed- there were plenty of other attachments that kept the fender in place anyway. But Kawasaki was apparently concerned about customer perceptions and haviing stainless welds redone by dealers so took action with all owners to forestall the problem. I owned that bike for 12 yrs and for 6 of those, used it daily in all kinds of weather including snow and rain (I didn't own a car then) and it never quit on me.

Prevention beats hell out of warranty coverage anytime, IMO, even though I'm in the minority of owners who can deal with most types of failures by themselves, on the road if need be.
 
Very informative thread. Now I hope I can remember all of that, or better yet I think at my next 6K I will just go through the motions that are described in this thread.

Thanks for the time and the research!

Jim
 
You are going to have to check to see what controller your bike uses. All of the above has to do with R1200 series bikes. I don't know what other models use the same controller, and I suspect that the 650 twin does not.
But I don't know. Check the parts fiche.

Ok, I just did and now I have to stand up and correct myself. It in essence is the same controller, but has a different part no. 778. I have no idea what that means, but it's the same controller, and they do report some failures on the new anodized, or powder coated, or ... black ones.
dc
 
From my reading on this issue, it seemed, the majority of the failures had "circumstances" associated with the failures. The mounting area seems to collect a lot of dust, sand and debris. Add water, let set and the corrosion and lack of cooling airflow helps croak 'em.
(the whole set-up is similar om my f-800gs)
 
While most of the early failures seemed to come from bikes ridden in the wet (lots in the GS UK database for example) some just die in the middle of a dry place. Whether they had damage from washing the bike by using a pressure washer or getting hose up uder the plastic, etc isn't always obvious. I suspect at least some that failed never saw any significant water...
 
Pictures, this thread needs pictures.

Last June...bike dies on highway. Dealer thought it was the controller before the bike was even off the flatbed. So far I've been lucky enough to pay for each major GS flaw out of my own pocket.
This was known issue #1. Final drive rebuild #2, Faulty Flange #3. Wooo Hooo.

5842695951_1b72347d84_b.jpg
 
The next R models will be an interesting test of whether BMW has learned anything about design quality review instead of relying on their company culture of compartmentalized expertise in the typical euro-matrix system where no one person is really accountable for much of anything.
The recent GS competitors may well be able to gain market share at BMWs expense if basic flaws that are well known haven't been corrected in those GS prototypes running around Europe. BMW has chosen not to make any fixes during the run of the current R designs unless they are cheap enough to be almost free to them (eg slightly larger FD bearing, drain plug, elimination of the needlessly gimmicky whizzie brake but no reworks of the expensive molds for fuel tanks so their well design doesn't destroy fpc's, for example)
One positive trend on the Rs has been the reduction of required maintenance from the first hexhead to the current camheads. It would be nice to see this continue in a much more fundamental way by use of a design that does not require splitting the bike in half every time one needs to do a minor bit on the tranny or clutch. Just because I can do my own work doesn't mean I want to waste that much time on it or pay someone else 10 hours of labor for what is half that time or less on most stuff.
 
It isn't quite an ALL MODELS problem for Hexheads. The subject came up recently on the R12R specific forum on r1150r.org - and no one had a failure to report. The fuel pump mounting is under the tank, and mounted in one of the inner side-wall lobes of the tank, so water would naturally drain out of the recess.
 
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