• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

R1150RT Fuel System Failure and Warning Light.

roger 04 rt

New member
A few days ago, doing 75 mph in the passing lane, my motorcycle started to feel slightly starved for fuel--slightly low power at full throttle. It took about 8-10 miles before the condition progressed and engine stopped dead. After a 2 1/2 hour wait and 100 mile tow (thank you BMWMOA Platinum Club), I've debugged this to the point that I know the problem is inside the tank (lots of fuel flow but no pressure) and will drain it (it's full of course) and figure out what's wrong later today.

Since the failure, I've been thinking about adding a low fuel pressure annunciator. Has anyone done this, have experience doing it on another vehicle, or have a suggested pressure switch?

The normal pressure in the fuel system according to the BMW spec is 3 bar (43 PSI), +/- 0.2 bar--a 14% range, which means without an O2 sensor AFR has a 7% range Open Loop but that's another thread. My understanding is that the fuel pump can put out 60 PSI or more which means that the return pressure is 10 PSI or more while the injectors are consuming fuel.

My thought is to put a 5 PSI (nominally) sensor switch in the return line and then connect that to a light on the front panel that would signal low return flow. If the pressure dropped below 5 PSI, that would mean the pump or hose or filter or something was acting up. My reasoning on the return line is that it might not be a good idea to add a connection on the high pressure line.

What do you think?
RB
 
I've got some photos of what led to the complete loss of power the other day. In a nutshell, all three high pressure hoses inside the tank need to be replaced. Two are not submersible and one is original and a moment away from rupturing. This highway shutdown was completely avoidable and began a year ago with the dealer's incompetent replacement of the fuel filter and was compounded when I ignored the red-flags.

Here is everything that flowed from that fuel filter replacement by the dealer's mechanic last year.

1) On my second day of ownership, the tank vent and filler neck drain began leaking at the right footpeg. The charcoal canister flooded. The dealer picked up the bike and replaced both those hoses inside the tank.

2) A couple months later, the fuel neck drain line started leaking by the right peg. It turned out that the filler neck was rotated 60 degrees counterclockwise, the two hoses were reversed, and the filler neck o-ring was swollen and not seated to seal the tank--all of which I repaired myself.

At this point I should have questioned the quality of the fuel filter replacement, right? I didn't though and ended up with a dead engine, coasting at 75 mph, in the left hand lane of I-93 south of Boston in heavy traffic.
-
This afternoon I pulled the tank. The first thing I noticed was that the high-pressure hose to the fuel pressure regulator/distributor is an inch or two short and under stress. I'll need to lengthen it.
fuelfix1.JPG


After pulling the fuel pump plate I found that vent hoses were triple-oetiker-clamped at the plate and damaged. Just waiting to leak.

Below is a photo of the fuel pump, filter, screen and hoses. The high pressure hose from the pump to the plate is original, brittle, eroded, still intact but ready to fail. It should have been replaced at the filter change. The hoses to and from the fuel filter were replaced with the filter and made from hose not rated for submersion. Both of them are so porous that fuel from the filter was weeping out while I took the photo. This is the source of pressure loss. The rounded hose has numerous cracks.
fuelfix2.JPG


Looking at the other side of the fuel pump your can see that somehow 1/3 of the black plastic cap that holds the strainer is broken off. You can see the fuel weeping through the U-shapes hose, and also see the stress on the external fuel hose..
fuelfix3.JPG


Here's a shot of the o-ring. It is old and cracked around its entire perimeter, hard as a rock and flat on one side. It was not replaced at the filter change.Also there's the piece of the internal vent line that was cut by one of the three clamps.
fuelfix4.JPG


For anyone with an eight year old (or older) R1150RT that isn't certain of the condition of the fuel pump, filter, gaskets and hoses, I hope my experience serves as an early warning. Until it fails, there's no way to know that your fuel system is on the verge of collapse. I'll be ordering all the parts on Monday.
 
Sorry to hear about this trouble you've been having Roger. I can empathize with your frustration. I once took my new to me 96 RT to a dealer for a diagnostic plug check for faults and while it was in the shop I decided to ask them to change the fuel filter which they did. Two weeks later my pump burned out due to debris in the tank. When I diagnosed the problem at home and removed the pump assembly I found the filter sock on the pump totally deteriorated and with a gaping hole with bits of thread hanging off the end of it. A small chunk of some hard gasket sealer, which a secure pump filter would have easily stopped was lodged in the pump inlet and some more of the same had jammed it up inside so the motor burned out.

How a trained mechanic could have replaced the filter and not mentioned the condition of the pump filter sock while he was in there is beyond me. When I asked the dealer about this they denied any knowledge of the issue despite the obvious evidence in front of them. Needless to say they will never see any service business from me!

It was a turning point for me though and I resolved to learn how to service the bike myself. I just don't go to service shops any longer unless I am far from home and need a tire or something of the sort that I cannot do myself under the circumstances.

I am sure you probably have done so already but in my case, I decided to soak up every ounce of gas in the tank and make dead sure there was no other debris in there before I replaced the pump and filter. Judging from what you have found already a thorough clean out is definitely in order. Good job finding the problem so quickly.
 
Do it yourself

Just another of thousands of stories about "technicians" doing incomplete/shoddy/stupid things.

I do most of my own work on my bikes. This habit started when I was 13 and my Dad hated motorcycles; thus no money from him for maintenance or repairs. When I became an adult with a good-paying job, I let a Volvo "technician" work on my new vehicle. That lapse in my judgment led me back to doing my own wrenching.

I have been fortunate with my BMWs. The first wrench on my BMW was a Moroccan we all called Jimmy. His English was not good, but we both understood enough French for him to show me some things about my /2.

My first new BMW was bought from Brown-Austell BMW in Columbia, SC [1973 R75/5] and Clanton Austell is still the mechanic I call when I am in over my head. In most instances he can get me through my problem with a phone call; but once I had to trailer my bike to his shop in Columbia, SC.

Two years ago, I bought a 1996 R1100RT to replace my 81 R100RT. I have been completely through it and the only thing that has ever had me stumped was here;

http://forums.bmwmoa.org/showthread.php?t=60007

My advice is to find a good source for the task you want to complete and a buddy who has some experience. Trust me, you care more about doing it correctly than the person who is on "flat rate" and trying to finish in record time.
 
I'm considering the Beemer Boneyard replacement fuel pump/filter/strainer/damper kit. Has anyone here had experience with this
 
I'm considering the Beemer Boneyard replacement fuel pump/filter/strainer/damper kit. Has anyone here had experience with this

Yep, installed the kit in a buddies 04 chromehead about a month ago all of the needed O-rings, clamps etc. were there. It's the one I will put in my RT this winter. The only reason I set foot in a dealership is to look at the new bikes every spring. Not going to replace my 04 RT anytime soon, but I like to look.
 
Guys,

Thanks for the continued support and suggestions. As you'll see below, this project continues to have a life of its own. Everything is getting replaced.

Boy, do I post this a lot LOL!

The two spec's for FI hose :

SAE 30R10 is for SUBMERSIBLE hose.
SAE 30R9 is for EXTERNAL use ONLY.

When buying in bulk, they are usually marked designating the different specs. Roger, sadly, yours isn't the first "professional" FI hose installation screw-up of which I am aware!

HERE is a handy dandy explanation of the 30R10 and HERE is an article on non-submersible fuel hose.

I just looked up 30R7 hose after reading those articles. It is a non-submersible, low pressure fuel hose. So guess where I found it?

Earlier I had mentioned leaking internal vent and drain lines inside the tank just after I bought the bike. The seller replaced both internal lines with new hose and triple/double oetiker clamps on each end. The new submersed hose is marked SAE 30R7, clear as day. This explains why it ripped so easily when I removed the fuel pump plate.

This makes the dealer/seller replacement of the fuel filter a 100% incorrect job. It's hard to be so perfect.

The fuel supply system is too unobservable to tolerate this many errors. Everything is going to be replaced.
 
Unfortunately this is typical

Guys,

Thanks for the continued support and suggestions. As you'll see below, this project continues to have a life of its own. Everything is getting replaced.



I just looked up 30R7 hose after reading those articles. It is a non-submersible, low pressure fuel hose. So guess where I found it?

Earlier I had mentioned leaking internal vent and drain lines inside the tank just after I bought the bike. The seller replaced both internal lines with new hose and triple/double oetiker clamps on each end. The new submersed hose is marked SAE 30R7, clear as day. This explains why it ripped so easily when I removed the fuel pump plate.

This makes the dealer/seller replacement of the fuel filter a 100% incorrect job. It's hard to be so perfect.

The fuel supply system is too unobservable to tolerate this many errors. Everything is going to be replaced.

Unfortunately, this is all too common. What happens is the difficult jobs get handed to the real mechanics and the new kids get the "simple" tasks like routine service needs. You now have evidence of how "routine" maintenance can go terribly wrong when trusted to persons who do not have the proper knowledge to do the task.
 
Unfortunately, this is all too common. What happens is the difficult jobs get handed to the real mechanics and the new kids get the "simple" tasks like routine service needs. You now have evidence of how "routine" maintenance can go terribly wrong when trusted to persons who do not have the proper knowledge to do the task.

You can say that again!

For 10 months I've been riding a motorcycle that was a fuel-pump-cycle away from failure and it did, in very difficult conditions. I am replacing all the hoses, filters and pump using a BeemerBoneyard kit and BMW OEM submersible hose. The fuel system is too important to leave to chance.

When I get the time, I'm going to add a pressure switch that signals fuel pressure below 35 PSI (approximately) and flashes the hazard lights or low Battery (or something like that).
 
Since I have to replace one of the external hoses that is too short, I'm looking at installing a pressure switch in the high pressure line. Here is one that has the right function and a link to it Pressure Switch :
1064.JPG


Then something like this (although I need to find 5/16" I think) in series with the high pressure fuel line Barb to NPT T Adapter:
555-15270.jpg


The pressure switch would be wired to ground and also wired to the Low Fuel light which would have a new meaning: either the fuel is low or the fuel pressure is low.

Since I don't have any experience with this hardware if anyone could suggest better or better suppliers, I would appreciate it.

RB
 
Here is a photo of the old hoses and the new U-shaped hose. I'm now of the opinion that the hoses that failed were BMW parts. I don't know their ages. The fuel pump hose looks older than the U and the other attached to the fuel filter.
fuelfix5.JPG


Looking at the old U carefully as it is expanded, you can see a series of radial cracks.
fuelfix6.JPG


Mine can't be the only original hoses that have these cracks or that are leaking fuel. It just got to the point where the hoses on my bike failed. If these hoses are leaking more than the Motronic and O2 sensor can compensate for but not so much that they've failed, or at WOT, you could easily get lean-surge or pinging.

Unless you attach a GS-911, your Motronic could be putting out fault codes (mine did at failure) but you wouldn't know.

Perhaps this type of failure might also explain why some 1100s and 1150s can't be richened in Open Loop mode. The fuel pressure is just not high enough (but at the same time it's not so low that the bike won't run).

A couple more photos of the filler neck and safety valve.
fuelfix7.JPG

fuelfix8.JPG
 
My injectors arrived from Marren Fuel Injection today. Here are the details of the report:

Injector Type: Sat 16.0 ohm
Test Pressure: 43 psi
Injector Part #: 0280155788
Test Pulse: 6 mS
Injector Maker: Bosch
Gravity Weight: 0.75 (what is this)
Static Flow: 350 cc/min
Remarks: Install new fuel filter

Before
Injector 1: 103.7 cc/min spray pattern: N/G (no good)
Injector 2: 108.0 cc/min spray pattern: OK

Reverse Cycle: Dirty, both injectors
Matching: 4.2% (I wonder what it was before 2 tanks of Techron Concentrate)

The 4.2% matching translates and a stock O2 sensor translates to AFRs of one cylinder running between 14.1:1 - 14.7:1 during closed loop and the other running between 14.7:1 - 15.3:1.

After
Injector 1: 108.9 cc/min spray pattern: OK
Injector 2: 111.1 cc/min spray pattern: OK

Leakage Test: Good, both injectors
Matching: 2.0%

I was hoping for a 2% or better match and am pleased with the results. This savings of 2% will, most likely allow me to raise my target AFR from 13.8:1 to 14.1:1 and get about the same results, perhaps better.

Waiting on the fuel pump which should arrive later tomorrow.
RB
 
Last edited:
No fuel pump in the mail today, I'm a bit in the hinterlands of Cape Cod. Most likely tomorrow. I did take the time to cut open the fuel filter to see how it looked. No restriction which I knew from fuel volume at low pressure and clean as a whistle.
 
The fuel supply rebuild is done, tested with GS-911 and LC-1 AFR control panel ... and test driven. It's been nine days from highway breakdown, through diagnosis, parts delivery and repair. Thanks to Beemer Boneyard and MaxBMW for their responsive service.

The replacement pump arrived today at noon by Priority Mail as Mike at Beemer Boneyard had promised and it worked great. I'd had everything ready, the pump got mounted and plate installed with a new gasket and torqued down to the fuel tank--45 in-lbs, not much. During installation I found a split fuel gauge O-ring in the bottom of the tank--Davey Jones locker.

Two gallons of fuel was put in the tank and checked for leaks. The tank held and I put some containers at the fuel distributor heads where the injectors connect and ran a couple quarts of fuel through the system to make sure there were no bits beyond the filter. The fuel stream was much stronger than before the repair.

The injectors were then connected to the Motronic and pointed into containers and the engine turned over to fire the injectors and verify the fuel path. (I plan to build a quick-disconnect fuel pressure gauge this week and measure the pressure. But all seemed well so the injectors were installed into the TBs.

The Motronic had been reset but the engine cranked over a couple more times than normal and the bike fired up. At this point the GS-911 and LC-1's AFR gauge were reading normally. There was nothing left to do but fill the tank and take a 15 mile test ride. The bike is running great.

Symptoms
In case this helps anyone else, a recap of the symptoms that preceded the breakdown:

-Some slight surging after a few miles.
-Lack of WOT torque for 5 miles
-Rough running for 5 miles.
-Then the engine died.

Looking back on this there were enough symptoms in the early part of the ride that I should have turned around. Hopefully I've learned a lesson.

Cause
The internal fuel lines split enough that there was inadequate fuel pressure. I'm going to make fuel pressure a part of annual maintenance and replace the internal hoses when I replace the filter.

Parts replaced
-Three small high pressure lines inside the tank
-Vent line inside tank
-Drain line inside tank
-10 internal clamps
-Beemer Boneyard OEM Pump Kit (pump, strainer, filter, o-rings, screw clamps)
-2 external fuel lines and 4 clamps
-2 fuel injectors sent to lab for cleaning

Given that the internal hoses appear to have been submersible, but old, I believe they should be part of a periodic service checklist.
 
Last edited:
For those who want to make a fuel system test of an R1150RT to check its condition, here's a straightforward method based on the fuel pump spec of delivering 110 liters/hour at 43 psi). Other systems may have different numbers.

Put a fuel pressure gauge in series with the high pressure line.

Take the return line and route it through a hose with a QD into a fuel container. Take all appropriate safety precaustions and have a proper fire extinguisher on hand. Do this outside if possible.

Start the motor and let it idle for two minutes exactly, then shut off the engine. You should have just under 1 gallon in the container. The fuel pressure during idle should read 43 PSI plus or minus 4 PSI.

Feel free to check the numbers, I'll be testing my system later this week or next.
 
broke down 150 miles from home . had fuel volumn and what i thought was pressure until i put a gauge inline on the pressure side and the gauge read zero.
first i thought the gauge was broken until i hooked up to my jeep and the gauge read 50psi. very surprised what i saw when i pull the sender out of the tank.

question. is it worth buying a gs911 for a r1150gs. is it just a code read or can you read data. or is there another way to read codes . being an auto tech i hate just swapping parts and would like to see what the motronics reads:violin:violin

check your road side assistance i was 150 miles from home when i broke down and progressive couldnt find a tow service
to tow my bike.
 

Attachments

  • bmw fuel line.jpg
    bmw fuel line.jpg
    51.2 KB · Views: 188
broke down 150 miles from home . had fuel volumn and what i thought was pressure until i put a gauge inline on the pressure side and the gauge read zero.
first i thought the gauge was broken until i hooked up to my jeep and the gauge read 50psi. very surprised what i saw when i pull the sender out of the tank.

question. is it worth buying a gs911 for a r1150gs. is it just a code read or can you read data. or is there another way to read codes . being an auto tech i hate just swapping parts and would like to see what the motronics reads:violin:violin

check your road side assistance i was 150 miles from home when i broke down and progressive couldnt find a tow service
to tow my bike.

That's some photo. Here are some numbers the bike will run quite well with leaking hoses that you could find by pressure/volume tests.

What I would say to that is that all three of the hoses, that I now believe are original, were degraded--time, heat, gasoline and alcohol exposure. The hose coming from the fuel pump was in the worst physical condition but not leaking. The other two hoses look almost new until you examine them closely. I believe that many motorcycles will have similarly degraded hoses in the tank unless they've been replaced.

I just looked up the pump spec which is 110 liters per hour at 43 PSI, the pressure our bikes run at. Our injectors have a maximum flow of 350 cc/min so two of them can flow 750 cc/min or 45 liters/hour. Cruising at 75 MPH requires 20% of the injectors max flow (or a little less) that's about 9 liters/hour.

So the hoses inside the tank could be leaking at the rate of 70 liters per hour and you'd never know it.

I don't believe the situation I found is unique. At the same time I'm not surprised that, as of yet, you haven't had a problem
.

On the1150s you can read a long list of real time values but not so on the 1100. Also you can read and clear faults, cycle the purge valve and fuel pump, set the TPS and some other things. No fuel pressure though since that is not monitored.

The innovate Motorsports LC-1 that I installed for a richer closed loop mixture has a big side benefit--real time monitoring and logging of air-fuel ratio. You really know what's going on.

I got the bmwmoa platinum tow service when I signed up. They brought me 100 miles for free, cost would have been about 200-250$. Good deal.
 
I got the chance today to split and study the hoses and see where the specific leaks were occurring. In the photo below you can see three splits:

--The worst, that I believe led to the breakdown, was in the U-shaped hose. It's a crack over 3/4" long on the inside and 1/2" on the outside.

--Also there were two splits on the hose going to the filter input each about 3/8" long on the inside and 1/8" and 1/4" on the outside.

It seems unlikely to me that all three splits occurred at the same moment. Most likely I've been driving for a long while with leaking "innards". It also leads me to conclude again that other bikes are likely to have this condition.

As long as the leaks are small enough that the fuel pressure remains around 43 psi which means that not more that 60-70 liters per hour (gulp!) are leaking internally, the motorcyle operates normally. Finally, one tears open and a catastrophic failure occurs.

fuelfix9.jpg
 
Today I put together a fuel pressure gauge and flow-volume testing setup to create a baseline for my R1150RT. The spec for the pressure regulator is 43 psi and the fuel pump is rated for 110 liters per hour.

Here's a photo of the fuel pressure gauge connected to two QDs salvaged from a plastic to metal QD conversion. And a female QD connected to a collection hose. The idea is to connect the fuel gauge to the high pressure feed hose, and connect the collection hose to the regulator side of the return line so that fuel bypassing the fuel pressure regulator is collected in the container and weighed. This way you can measure both the fuel pressure and total fuel volume.

In order to develop 95 HP (R1150 Max.), the system has to be able to output a minimum of 35 to 40 liters per hour.
fuelfix10.JPG


Here is the system connected to the motorcycle.
fuelfix11.JPG


Here is the idle fuel pressure, 44 psi.
fuelfix12.JPG


I ran the motorcycle for 60 seconds and collected 3 lbs. 13 oz. of fuel which equates to 0.64 gallons (6 lbs. per gallon), which translates to 145 liters per hour. Much better than the pump spec of 110 l/h and easily 3 times the amount required to produce full power. Every 10 minutes the pump runs 5 gallons of fuel through the system.

Thinking back on the failure of my system and the multiple cracks in the hose. I suspect that my system was running fine with some leaks but then one opened to the point where there was little to no fuel pressure. If I'd been measuring pressure and volume once a year I might have caught this long ago.

The 145 l/h will serve as a baseline for future measurement to assess the health of the fuel delivery system including pump, filter and internal hose condition.

As a side note, the new pump is noticeably quieter than the old one. Also the engine is noticeably smoother (am I imagining this?) Which I believe is due to the better injector matching (< 2%) after cleaning.

RB
 
Back
Top