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Help With Fuel System R1100RS

67289

New member
First post here. Should make an intro but not much to say. Anyway:

My background: Riding 30+ years. Flying little planes an equal time. FAA A&P mechanic but occupation is mold maker.

Bike's background: 1995 R1100RSL. 45K miles. I bought new 11/94. Performance wise bone stock. Only minor farkle: solo seat, tail cowl, etc.

Situation: For whatever reasons which most find irrelevant, this bike was dormant for 24 months. I now want to resume its use. It is being recalcitrant in awaking from its slumber. I contacted two dealers about working on this...one denied it outright and the other was presenting a very unenthusiastic attitude. I decided to attempt this myself. This cycle was usually serviced by the dealer so I have limited data for servicing. First step order manuals and they are on their way. As yet I have no schematic.

What's going on: I have checked some things over and have a new battery installed. All lights operate as should when starting: Dual ABS flashing in synch, RID is powered up and appears normal including clock function. All remaining lights and horn function. What fuel was in tank had been treated prior to storage with Stabil. I did not drain this remnant but did add fresh fuel...perhaps a gallon. I would estimate a total of 2 gallons present. Engine cranks but we get no start up. Raw fuel was introduced thru airbox and we get start up until fuel is expended. Oil pressure light extinguished during the brief start. This would indicate we have a sound (enough for start up and further testing) ignition system but a problem in fuel delivery.

OK. Sound reasonable so far? Now this gets foggy for a non-electronic EFI person as me! I have read and searched as much as I could here and another forum. Please bear with me if this has been covered a million times!
I noticed I heard no fuel pump spool up during initial power on.
I tried to remove the "out" line from the tank and power up to see if fuel would come out. Negative.
Check fuse #6. Fuse is sound but swapped it with spare.
Swapped relay #6 with horn relay. Same result.

Perhaps the fuel pump is dead. We should pull the filter anyway after layup as this. So off with the tank and pump is removed. Looks sound with no remarkable issues. When connected to a 15 AMP battery charger, the pump vibrates mildly and draws 9 amp. The lead end warms very rapidly. Removed pump from mounting plate/tube and removed strainer. The impeller appears locked up. At least I think that is the impeller! Thoughts?

I have ordered a new pump kit and all the sundry supplies to make the replacement. We await their arrival.

In the meantime, I decide to make sure power was headed to the pump. I power up the bike, all the normal indications as discussed above. When a voltmeter is connected to grnd and the other lead to the green wire pin in the chassis's connector for the fuel pump/gage assembly, I get no power. I have plugged the pump/gage assembly (less the pump so the terminals that attach to the pump studs are free and touching nothing) back into the chassis plug and plug in the ground. A check for voltage across the two pump ring terminals shows no voltage present. Continuity was checked at the bulkhead terminal of the plate so the circuits are sound thru the plate.

That is the question I have today (I am sure there will be more before this runs if you folks will oblige me!): Why is there no voltage present at the chassis plug fuel pump power pin? Pressure sensor? Ideas? Help?

Thanks in advance for your patience and help!
 
I'm operating from memory here from my '96 R1100RSL ('97 - '10), but I think the fuel pump is only given electricity with the ignition on in these two circumstances:

1) For just the first second or so after the ignition switch is turned on (to pressurize the system), and
2) If the engine is turning over, which can come from either the starter turning the motor over, or the engine running.

#2 is detected by the HES. When it detects crankshaft rotation, it advises the Motronic which then turns on the fuel pump and the spark.

An easy way to assess fuel delivery is to withdraw the injectors from the intake manifolds one at a time, leaving them connected electrically. Outside (atomized fuel is very flammable), point the injector into a topless tin can, turn on the ignition, and push the starter button. The injector should produce a fine and regular spray. A stream or a dribble indicates the injector needs repair or replacement. No fuel delivery at all may indicate a failed injector, or some other fault (fuel pump not running so there's no fuel pressure, injector not receiving a command to open).
 
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You are absolutely correct dbrick. To a tee.
I connected a test light to pump pin in chassis plug and grounded the other end. When key switch is turned on power is available at the pin. After about two seconds and exactly when the ABS flasher relay begins clicking, power to pump is canceled.
When engine is cranked, power returns to the pump pin.

Spot on with your post.

That solves that and places the lack of fuel we were experiencing directly on the pump itself. Everything external to the tank appears ready to function. As mentioned, we will see what happens once the new pump kit and misc. parts arrive and are installed.
We will pull an injector as you suggest at that time and start up as well.

Thank you for the prompt and accurate information! Stay tuned!:wow
 
Ah...The name is Eric Zimmerman.
Mold maker by trade in the rust belt. Two funnest hobbies among many are motorcycling and antique airplanes. That is my MOA membership number so I've been around for a bit. Currently down to two Beemers...the R1100 of subject and an ol' airhead '80 R100S.

I was stuck thinking the pump should be powered when key switch on and ready to start because another injected bike I have runs the rather audible fuel pump about 5 or 10 seconds before it cycles off. That bike is a handsome and wonderful sounding '97 Guzzi 1100i Sport. It is no BMW but it certainly does have character!

We'll post our results here when we get the parts. I am sure there will be other things needing attention after a two year lay up...likely ABS issues.
 
The above comments re pump function are correct.

I have seen this a couple of times on bikes that have sat for a period of time.

When removed and voltage applied to the pump directly the armature would not turn.

I the first case I removed the filter sock, filled the intake with carb cleaner and gently pried the armature assy. with a small screwdriver and it eventually released (suspect gummy pump internals) After that the pump ran fine and has ever since.

In the second case I did exactly as above with no success. I then did an autopsy (destroying the pump) and found a very light layer of rust on the pump surfaces (very similar to an engine oil pump) - just enough to jam it.

In light of the above if I had my machine in storage I would cycle the pump a few times (no need to start the engine) every 6 months.
 
Eric -

I'm in North Ridgeville (west side of Cleveland) and have a 1995 R1100RS/RSL that I ride and a 1996 that I'm parting out. If you are in the area and have an issue where you want a bike or parts for comparison / troubleshooting, let me know. (the fuel pump in the parts bike is broken, so I'm no help there)

Also, check your hoses in the tank well. A buddy of mine just picked up a R1100S that had been sitting with a nearly empty tank for a year and a half. the "U" hose between the pump and filter had dried and cracked. It was bleeding off pressure such that the bike would barely run. We swapped in the hose from my parts bike and he was back in business.

- Jonathan
 
Thank you for the tips.
I have ordered virtually EVERYTHING inside the tank and am replacing all those items with the exception of the fuel level sender and the filler cap assembly.
I will be replacing all internal hoses including the pre-molded U tube with BMW hoses (that are rated for gasoline immersion). I have fuel and injection rated hose available for external plumbing.
I like Oetiker clamps but have opted to use screw clamp (not the tangential worm style but similar to OEM style used external of tank).
In attempting to remove pump from the plate assembly, I got a little over zealous with cutting the pinch clamp loose and broke the pump outlet nipple! Well, that pretty well cinched I'd need a new pump. I continued to remove the pump and then the strainer/sock. One of the heat sealed ends of the sock was long gone and has since been fished from tank. This means the sock was wide open on one end and of no use. Tank by the way, is exceptionally clean internally.
Upon removal of sock, I examined the pump thru the suction port that the sock was attached to. You can see small vertical vanes that appear to be part of the rotating impeller. I used an awl to try to rotate pump rotor either direction. We could get perhaps 5 degrees of rotation either way. I applied power to pump and watched these vanes. When forced to the extreme direction opposite normal rotation, the pump would drive the impeller 5 or 8 degrees then stop and hum and proceed to get very warm real quick on the lead end. Clearly, the rotor/impeller of pump is locked up from varnish/debris/corrosion. This made me feel a little better about breaking the nipple off!

I agree, it would appear if the system were simply cycled every quarter, much of this likely wouldn 't happen. I was amiss and treated it like an Airhead...nothing to do there but pull the Bings and clean...piece o' cake!

Jonathan, Thanks for the offer. I will be up that way (Vermillion) perhaps in a month or so to pick up an airplane engine. I am down around Dayton area. If this isn't running by then perhaps we'll need something.

When a new pump arrives with all the rubber parts anew, I suspect we may see some injector varnish issues. Can these be "do it yourself" serviced in some manner? I should be taking this a step at a time but cannot help looking ahead a bit. I am dreading if there are issues with the ABS, but certainly somebody here has the experience to guide us thru...I hope!

Thanks again and we'll post some results soon! :)
 
Since the bike has been sitting two years, while you are waiting for the tank innards it might be a good idea to just pull the injectors off and take them to any automotive injector service place. If a Bosch injector place is available go to them.

These injectors cannot be disassembled and rebuilt like diesel units but they can be pressure cleaned which will thoroughly flush out any varnish that has collected inside. Ask them to replace the inlet filter baskets at the same time. It is not that expensive to do this and might save you some headaches after the pump is replaced.

I bought a ten year old 1100 RT bike with 6425 miles on it and having this done made a big difference. I think it had sat for a couple of years steady when I bought it. The gas tank stunk something terrible and it ran very poorly but luckily it did run.

The Bosch shop tested the flow rate before and after flushing to see how bad they were but they have should have the specs regardless. They also know just by looking at the spray pattern (should be perfectly conical) if there is a problem.
 
That's a splendid idea. I'll see if I can round up a shop...perhaps even mail order as I am not in too great of a hurry! I still have the ol' Airhead humming.
 
Well, we got all the parts to replace all the tank internals...

2410527400053518643S600x600Q85.jpg


Sock, pump, U hose, internal hose, clamps, O-rings, filter, blah blah blah.

Remarkably, it fits!


2562587980053518643S600x600Q85.jpg


No real issue but it is tight so be careful to note where things were prior to disassembly. What is an issue are the clamps. These can be arranged so that the ears of the draw screw will not permit re-insertion thru the mounting hole in tank. May need to position screw clamps carefully to permit tank installation as well as not to foul float arm of fuel level sender.


Some vapor crud built up on the inside of filler neck...

2329314140053518643S600x600Q85.jpg


Gray ScotchBrite takes care of that.

Tank is mounted again and with an ear against tank, the pump can be heard at power up. Fuel level reads empty as it should as well as low level light is now illuminated. We're ready for a test with this phase.
But, we've mailed off the injectors for a cleaning, flow rate check and strainer change. Perhaps next Tuesday we'll plug them in and fire up.

Thanks folks for the assistance thus far!
 
Mark It!

Eric,

++1 on the suggestion to be VERY CAREFUL when you re-install the assembly into the tank, otherwise you'll get the float arm all tangled amidst the various lines, and you'll be using your odometer for a gas gauge. Ask me how I know. . .

Also, and not to rain on your parade, but I hope an "old wrench" such as yourself remembered to mark the exact "clock" position of the assembly before taking it out. It's easy to lose orientation when you re-install, and booger (technical term) the function.

The other tip is to use a little lube on the big-ass (technical term again) O-ring that mounts the assembly to the tank. The manuals say "replace," but I've re-used mine as it was flexy and no marks or scars, and I've never had a leak. Most say, DO NOT use any gasket seal on this monster, and I'd agree. Kinda scary when you look at this huge O-ring and realize it's holding back all that flammable high-test just above the right jug!

Glad this was relatively easy to diagnose, and hope this is the end of the troubles. Man, these two-wheelers do like to be taken out for a "walk" at least once a month, eh?

If you get tired of that airhead. . .

Regards to all,

Walking Eagle
 
Also, and not to rain on your parade, but I hope an "old wrench" such as yourself remembered to mark the exact "clock" position of the assembly before taking it out. It's easy to lose orientation when you re-install, and booger (technical term) the function.


Absolutely mandatory step that is oft omitted! Evidently the dealer previous to me had done just that...there was a large grease pencil hash across the plate and tank to reference the clocking of the plate. Very good point!

The other tip is to use a little lube on the big-ass (technical term again) O-ring that mounts the assembly to the tank. The manuals say "replace," but I've re-used mine as it was flexy and no marks or scars, and I've never had a leak. Most say, DO NOT use any gasket seal on this monster, and I'd agree. Kinda scary when you look at this huge O-ring and realize it's holding back all that flammable high-test just above the right jug!


I installed it dry. Upon disassembly I was surprised with the amount of effort needed to peel it from the plate. As if it were bonded in some manner. A difficult task at best seeing as there is no location points to do so. The O-rings were in good shape flexibility wise, but they had taken a deep set on the face that seals upon the plate...it was now a D ring! Age I suppose.



Glad this was relatively easy to diagnose, and hope this is the end of the troubles. Man, these two-wheelers do like to be taken out for a "walk" at least once a month, eh?

This is the first time I have ever messed with injection. I can handle Bing CV's with relative ease. My apprehension with EFI is perhaps unwarranted...we'll see if the machine runs before we call it a success!
That is for certain. A simple fire up and idle would have "kept the joints loose".

If you get tired of that airhead. . .

It is an '80 R100S. And here's a little comparo between technology and simplicity. I am not meaning to start a fight or fuel a fire. Both the R1100RSL and the R100S were laid up an identical time. Both were treated in same manner. They were side by side. I tried to bring them on line at the same time. Guess which one was "eager" to run? That's right. The old one with all the "nightmarish" points and gravity feed carbs. All it needed was removal of the two Bings and cleaning the bowls and the one jet. Re-installed , fired up and synched with the "obsolete Mercury stix" . No issues. And which one am I working on one month later? :D

No, that Airhead is staying right here! While it has that "seat jacking" issue upon acceleration and strange wandering idle speeds...it's a keeper. I swear it'll run on 'Lectra Shave lotion! :D
 
Well, we got our injectors back. This guy seems to know his stuff. I thought it was a reasonable cost and turnaround time great. He also provides a print out of the before/after performance...


2717340200053518643S600x600Q85.jpg


I blanked out the guy's name and addy...I don't know how the board stands on plugs as this.
You can see the gains in flow rate of 5.13 and 7.89% after cleaning and strainer change. substantial enough to make things smooth. Better yet, they are now identical flow rates.
I think this was a worthwhile procedure that should be taken seriously. Thanks 156327 for the suggestion!

After installing injectors as per procedure, we dumped in some fuel and lo and behold...IT RUNS! Not only does it start and run...it sure sounded quite smooth and idled perfectly. I didn't run it very long. I have the wheels off while I await new tires so I can mount them up and a concurrent fluids change out as well. The bottom line is we have the machine running and soon will get road test. I would now also strongly advise pulling those injectors and having them looked at if undertaking this type of work.
Thanks all! :thumb
 
Well, we got our injectors back. This guy seems to know his stuff. I thought it was a reasonable cost and turnaround time great. He also provides a print out of the before/after performance...


2717340200053518643S600x600Q85.jpg


I blanked out the guy's name and addy...I don't know how the board stands on plugs as this.
You can see the gains in flow rate of 5.13 and 7.89% after cleaning and strainer change. substantial enough to make things smooth. Better yet, they are now identical flow rates.
I think this was a worthwhile procedure that should be taken seriously. Thanks 156327 for the suggestion!

After installing injectors as per procedure, we dumped in some fuel and lo and behold...IT RUNS! Not only does it start and run...it sure sounded quite smooth and idled perfectly. I didn't run it very long. I have the wheels off while I await new tires so I can mount them up and a concurrent fluids change out as well. The bottom line is we have the machine running and soon will get road test. I would now also strongly advise pulling those injectors and having them looked at if undertaking this type of work.
Thanks all! :thumb

Well that's pretty cool that they provide the data. Now you know for sure there was a bit of a problem there and it is resolved. I think any bike that has sat for a long time (like my latest bike did) is going to have these sorts of issues. I don't know if the ethanol laced gas we get now makes it worse but injectors do get varnish deposits when they are not used all the time. I know mine felt and ran better after I got them pressure cleaned. Looks like yours did too! Glad to hear the bike runs now. The key to getting these motors to run right is for everything to be equal on both sides or they surge.

After I got my injectors back I also ran some IsoHeet through to absorb any water that may have been sitting any nooks and crannies too.
 
Dish!

Eric,

First of all, congratulations on solving the problem with relative ease -- that's a REAL GOOD feeling, I know. . .

Second, and not to step on Moderator's toes, but many of us are located (at least) halfway to Nowheresville, and must rely on service providers all over the world, literally. Sooooo --

Supporting (especially small) craftsmen and merchants is a sacred duty, IMHO, particularly in these troubled economic times, so UN-REDACT, please, and we can send some business this guy's way when the need arises. After your experience, as well as HW's experience w/ injectors. . .it's got me wondering how much better my RS can be. . .BE all you can BE. . .

Well done! And thanks for sharing. Is this a great site, or what?

Regards,

Walking Eagle
 
As mentioned, I work as a machinist. And despite what the current consensus regarding the economy, manufacturing in the Midwest is hopping. We are currently on 60 hour weeks covering 6 days. That leaves Sunday off. I know and respect the adage of supporting your local dealer or mechanic. But I have none within 1 hour. The dealers basically declined working on it. The one (yes, a BMW dealer) called this type of work a "restoration". I was fully prepared to hand it over but was unable to find someone within a reasonable trailering distance that wouldn't cost me substantial time off work. Better do it myself.
The same with the injector cleaning. I called about town (again, it had to be within a reasonable distance due to time constraints) and could not find anyone willing to undertake the work. I suppose if I hung around their garage all day and drank beer with them they'd oblige. But not so much for a walk in stranger. Mail order was a much easier transaction. I can stop at the Post office and send them off and them await their return by UPS. No lost work time, no guessing. I surfed around the net late at night and came up with this fellow. There are lots of places that "tune" injectors for performance but I wanted a simple "stock" treatment. He was happy to do just that. There are very few here who do not have an alternative bike to ride while one is being repaired...or at least a cage to drive. So there is not much of an excuse to not use mail order services when there is a lack of local alternatives.

I will take a chance on being banished to the dark recesses of the board by the mods or receiving admonishment by email and post a link to the fellow who took care of this.

You can try FUEL INJECTOR MAN
He is in FL with a history of outboard motor injector work. He will work on all gasoline EFinjectors. Has all the specs. Turnaround is 30 hours or less. You printout his little order form fill it in and send it to him along with the injectors. he emails you an invoice when he receives them. There is a flat rate per injector. PayPal (or CC) payment and they are on their way back to you.
Easy peasy lemon squeezy!
 
Fuel Injector Man. . .

looks like the guy.


$16/ea. for the cleaning service on top-feed injectors???

+ postage = a good deal.

THANKS, and enjoy that ride on your one day off. . .OUCH!

Walking Eagle
 
You are welcome. I didn't know whether the price was good or not. I figured as I was prepared to pay somebody to work on this motorcycle revival, I'd be faced with a substantial bill. So $50 or 60 would be well less than a hired repair. The bill for the two injectors was all up $43.72 back to me. Add in $6 or so mailing to him and we are under $50. If I had paid a local mechanic I would have saved on $17 shipping but likely would spend near 50% that in taxes. So I counted it as a reasonable transaction. I suppose some would get their undies in a bunch over having a week turnaround (I mailed them on a Friday eve after pick up had left and UPS delivered them on Thursday PM) but I had another bike to ride.

I had called Fuel Injector Man prior to sending them off. We got into an interesting coincidence. He asked where I was and I told him North of Dayton OH. Turns out he was a Union electrician and had worked in the SW OH area including the large former Panasonic tube manufacturing plant no more than 5 miles from me! Small World...so behave. You never know who you'll run across!
 
I live in Vancouver BC and used a guy called Fred Holmes Fuel Injection Ltd. He's the Bosch guy and the business is in Richmond BC. Close to me...

I got charged $5.50 for new inlet filter baskets, $5.00 for new O Rings and $50 to pressure flush and clean both injectors. Total bill was $67.50 and I dropped off /picked the parts. He had them for several days since the shop was busy. Mainly they do really BIG injectors like ship engine diesel stuff and large equipment.

Given the great service and the fancy report showing the exact numbers I'd say you got a whopping good deal! Don't cha love real data? I do...:laugh

My guy did let me know the spray pattern was not great and that the flow rate was improved after cleaning, more so on one than the other. So basically the same problem and solution as yours really. He also stated that varnish deposits from old gas inside was the culprit for sure.
 
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