Page 1 of 3 1 2 3 LastLast
Results 1 to 15 of 39

Thread: fuel pump failure?

  1. #1
    aapasquale
    Join Date
    Aug 2011
    Location
    Sag Harbor, New York
    Posts
    128

    fuel pump failure? VICTORY!!!

    Hi all-
    Just got back from a trek to Bob's BMW in Maryland. Had SS braided brake cables and bar-backs installed on my 1994 R1100RS--drove back and forth from east end of Long Island (about 600 miles)--when within 1/4 mile of my home, bike just stopped and would not restart--battery good, fuses good--cranks well but doesn't turn over--when turning switch on, I don't hear that familiar whirring sound of fuel pump bringing fuel line up to pressure--I'm assuming this is a fuel pump problem--bike has 40,000 miles--any other suggestions before I call Beemer Boneyard and others for a replacement? Thanks in advance for your input.

    Tony

    PS--Bob's is very good--worth the trip--traffic in that area is unbelieveable!
    Last edited by aapasquale; 05-06-2013 at 08:50 PM.

  2. #2
    Registered User roger 04 rt's Avatar
    Join Date
    Oct 2011
    Location
    Massachusetts
    Posts
    1,207
    Quote Originally Posted by aapasquale View Post
    Hi all-
    Just got back from a trek to Bob's BMW in Maryland. Had SS braided brake cables and bar-backs installed on my 1994 R1100RS--drove back and forth from east end of Long Island (about 600 miles)--when within 1/4 mile of my home, bike just stopped and would not restart--battery good, fuses good--cranks well but doesn't turn over--when turning switch on, I don't hear that familiar whirring sound of fuel pump bringing fuel line up to pressure--I'm assuming this is a fuel pump problem--bike has 40,000 miles--any other suggestions before I call Beemer Boneyard and others for a replacement? Thanks in advance for your input.

    Tony

    PS--Bob's is very good--worth the trip--traffic in that area is unbelieveable!
    First thing, check the fuse 6.

    Second thing, swap the fuel pump relay with the load relief relay.

    Next, make sure the connector on the right side, just below the fuel tank, is fully seated. Since that is what was taken apart to do the SS brake lines, that's the first place to look.

    RB

  3. #3
    Macrunch MCrenshaw's Avatar
    Join Date
    Mar 2008
    Location
    Bedford, TX
    Posts
    77
    If the fuses and fuel pump check out OK, I would look to the Hall Effect Sensor (HES). The HES itself doesn't usually go bad in bikes of this age but the wiring insulation can become embrittled and cause the failure. The bike will crank just fine but will not start.

  4. #4
    Registered User
    Join Date
    Jan 2011
    Location
    Sus-Q Valley
    Posts
    96
    Quote Originally Posted by aapasquale View Post
    Hi all-
    Just got back from a trek to Bob's BMW in Maryland. Had SS braided brake cables and bar-backs installed on my 1994 R1100RS--drove back and forth from east end of Long Island (about 600 miles)--when within 1/4 mile of my home, bike just stopped and would not restart--battery good, fuses good--cranks well but doesn't turn over--when turning switch on, I don't hear that familiar whirring sound of fuel pump bringing fuel line up to pressure--I'm assuming this is a fuel pump problem--bike has 40,000 miles--any other suggestions before I call Beemer Boneyard and others for a replacement? Thanks in advance for your input.

    Tony

    PS--Bob's is very good--worth the trip--traffic in that area is unbelieveable!
    LLOOOOVEEEE Bob's!!! Sister lives in Annapolis and I always build in time to stop!!
    Tonya
    2007 F800ST - Lovin' it!!

  5. #5
    Registered User dieselyoda's Avatar
    Join Date
    Mar 2013
    Location
    Winnipeg, MB, Canada
    Posts
    398
    I'm not sure about your bike, but my 96 R1100RT, the load relief relay and the starter relay are different. On mine, the starter relay has a diode in it and it's BMW proprietary. I've cooked two in the last few years and now I have a spare for myself or my buddies. All the other relays can be swapped by part number from NAPA. You can do some detailed troubleshooting of the pump and hot wire as well. Pin 2 is power and Pin 1 is ground. You should have less than a tenth of an ohm to ground and between Pins 1 & 2, around 3 ohms is good. That number can be a bit higher to almost 10 ohms depending on temperature but 0 ohms be bad.
    1997 R1100RT (Restored Basket Case) , 1981 KZ 440 LTD (Restored Basket Case)
    1986 K75S(the beutch), 1993 K1100RS (blown engine), 1997 Chev Short Box (4x4 with an LT1)
    "Life isn't about how fast or how high, it's about how well you bounce."

  6. #6
    Registered User dieselyoda's Avatar
    Join Date
    Mar 2013
    Location
    Winnipeg, MB, Canada
    Posts
    398
    Ignore my last post. Me bad.
    1997 R1100RT (Restored Basket Case) , 1981 KZ 440 LTD (Restored Basket Case)
    1986 K75S(the beutch), 1993 K1100RS (blown engine), 1997 Chev Short Box (4x4 with an LT1)
    "Life isn't about how fast or how high, it's about how well you bounce."

  7. #7
    aapasquale
    Join Date
    Aug 2011
    Location
    Sag Harbor, New York
    Posts
    128
    Quote Originally Posted by MCrenshaw View Post
    If the fuses and fuel pump check out OK, I would look to the Hall Effect Sensor (HES). The HES itself doesn't usually go bad in bikes of this age but the wiring insulation can become embrittled and cause the failure. The bike will crank just fine but will not start.
    How do you go about testing the fuel pump? Does it have to be removed from the tank or is there a test which can be done externally? How does one go about testing the Hall Effect Sensor?

    I checked the #6 fuse on my bike this morning and it is fine. I pulled apart the connector under right side of fuel tank and it is perfectly clean. I will hook up a voltmeter and Ohmeter and see where things lie. Will check relays during the next couple of days as well and will report back. I love this stuff!

  8. #8
    Benchwrenching PGlaves's Avatar
    Join Date
    Oct 2003
    Location
    "Big Bend" TX
    Posts
    8,486
    Quote Originally Posted by aapasquale View Post
    How do you go about testing the fuel pump? Does it have to be removed from the tank or is there a test which can be done externally? How does one go about testing the Hall Effect Sensor?

    I checked the #6 fuse on my bike this morning and it is fine. I pulled apart the connector under right side of fuel tank and it is perfectly clean. I will hook up a voltmeter and Ohmeter and see where things lie. Will check relays during the next couple of days as well and will report back. I love this stuff!
    Two things activate the fuel pump. Turn the key on - all other interlocks such as the sidestand, neutral switch, kill switch, etc) closed - the Motronic energizes the fuel pump for a few seconds without any signal from the Hall Effect Sensor. So if the normal key on routine is not starting the pump there is no reason to suspect the HES.

    I don't know the pinouts on the connector on the tank, but applying 12v to the 12v pin and ground to the ground pin on the tank side of the connecting plug should make the pump run. You will need to find the schematic and have a couple of 2 foot jumper wires to the battery to perform this test.

    Before I did anything else I would check the fuse, check the relay, unplug and inspect the tank connection and unplug and check the big plug at the Motronic. I would also check, and jumper if needed, the sidestand switch. My bet is it is either a loose connection or the sidestand switch.

    PS: When I installed Motolights on an R1100RS I used a switched circuit that was killed with the sidestand switch as the trigger for the Motolights switch and relay coil. It has caused a couple of panics when the Motolights didn't come on because the sidestand was down, but it sure makes troubleshooting the sidestand switch easy if I remember.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  9. #9
    Registered User roger 04 rt's Avatar
    Join Date
    Oct 2011
    Location
    Massachusetts
    Posts
    1,207
    Quote Originally Posted by aapasquale View Post
    How do you go about testing the fuel pump? Does it have to be removed from the tank or is there a test which can be done externally? How does one go about testing the Hall Effect Sensor?

    I checked the #6 fuse on my bike this morning and it is fine. I pulled apart the connector under right side of fuel tank and it is perfectly clean. I will hook up a voltmeter and Ohmeter and see where things lie. Will check relays during the next couple of days as well and will report back. I love this stuff!
    If your fuel pump isn't coming on at key on, I don't see how that would be caused by a failed HES. At that point the engine isn't turning.

    Next, as you've said you plan to, swap the Load Relief and Fuel Pump relays. OR pull the fuel pump relay and jumper pin3 to pin5 in the socket. The fuel pump will run even with the key off.

    The other day while doing some testing, I had the bike on the sidestand, and in first gear, turned on the key to power up the fuel pump for 2 seconds so I could check power at the injectors (also from the fuel pump relay) ... NOTHING.

    On your R1100, in order for the Motronic MA 2.2 to energize the fuel pump relay, the Motronic Relay must work and be energized. That circuit requires that Fuse 5 is good. Also the Kill Switch and Sidestand Switch must be working (if your RID comes on with Key On then those two switches are okay. Therefore if swapping the Load Relief and Fuel Pump relay don't make a change, check Fuse 5 and swap the Load Relief with the Motronic Relay (consult your manual so you know which relays are which).

  10. #10
    aapasquale
    Join Date
    Aug 2011
    Location
    Sag Harbor, New York
    Posts
    128
    Quote Originally Posted by Roger 04 RT View Post
    First thing, check the fuse 6.

    Second thing, swap the fuel pump relay with the load relief relay.

    Next, make sure the connector on the right side, just below the fuel tank, is fully seated. Since that is what was taken apart to do the SS brake lines, that's the first place to look.

    RB
    thanks Roger--
    fuse #6 is good--switched load control and fuel pump relays..no go (I suppose that could mean both are good ....or bad!)--checked electrical connector to fuel pump/sender...clean as a whistle and solid--

    --is there an external test to check fuel pump so I don't have to remove it?
    --new fuel pumps are available from ReCycle for half the price of OEM and I don't mind opening up the bike to replace it, but I'd like to be sure that is the problem.

    --are there checks to determine if Hall Effect Sensor is functioning? Also, have friends who have had this problem on RTP's and have had to replace computers--is there a check which would show this up?

    When this problem is rectified, I'll be in touch concerning our previous discussion of surging issue--thanks again for the use of your booster plug

    Tony

  11. #11
    aapasquale
    Join Date
    Aug 2011
    Location
    Sag Harbor, New York
    Posts
    128
    Quote Originally Posted by Roger 04 RT View Post
    If your fuel pump isn't coming on at key on, I don't see how that would be caused by a failed HES. At that point the engine isn't turning.

    Next, as you've said you plan to, swap the Load Relief and Fuel Pump relays. OR pull the fuel pump relay and jumper pin3 to pin5 in the socket. The fuel pump will run even with the key off.

    The other day while doing some testing, I had the bike on the sidestand, and in first gear, turned on the key to power up the fuel pump for 2 seconds so I could check power at the injectors (also from the fuel pump relay) ... NOTHING.

    On your R1100, in order for the Motronic MA 2.2 to energize the fuel pump relay, the Motronic Relay must work and be energized. That circuit requires that Fuse 5 is good. Also the Kill Switch and Sidestand Switch must be working (if your RID comes on with Key On then those two switches are okay. Therefore if swapping the Load Relief and Fuel Pump relay don't make a change, check Fuse 5 and swap the Load Relief with the Motronic Relay (consult your manual so you know which relays are which).
    sorry I didn't see these comments before my previous post--will check this out tomorrow
    thanks!

  12. #12
    rabid reader dbrick's Avatar
    Join Date
    Apr 2003
    Location
    Santa Cruz CA
    Posts
    1,674
    Tony,

    The HES failure is actually failure of the wiring to the sensors, not of the sensors themselves, and are common in older Oilheads. HES wiring failure is more likely the cause of the bike's sudden death than a failure of the fuel pump. Here's info about the HES and its wiring:http://advwisdom.hogranch.com/Wisdom...ll_sensors.pdf In short, the wiring's insulation can't stand up to the heat (the wiring's in a hot place) and eventually fails.

    Certainly continue with the diagnostics suggested here. If the pump doesn't ever go on, it may indeed be faulty., But many of us who had HES difficulties on Oilheads (I did on my '96 R1100RSL at ~120K miles) also had fuel pumps that ran without difficulty.
    David Brick
    Santa Cruz CA
    2007 R1200R

  13. #13
    aapasquale
    Join Date
    Aug 2011
    Location
    Sag Harbor, New York
    Posts
    128
    thanks everyone--
    will take some time to digest all this but will give you an update when done
    Tony

  14. #14
    Day Dreaming ... happy wanderer's Avatar
    Join Date
    Mar 2010
    Location
    Vancouver, B.C. Canada
    Posts
    1,813
    As per Paul Glaves suggestion why don't you hot wire the pump itself to check it. They are quite reliable normally and usually the problem is somewhere else. I looked at Doug Raymonds schematic.

    http://www.mac-pac.org/tech/electrical-diagrams/

    If you put 12 VDC on Pin 2 and ground on Pin 1 the fuel pump should spin. If it doesn't the pump may be your problem or the wiring to it etc. but if it does the interlocks need to be confirmed and you need to trace the voltage back to the fuse/relay box.

    Side stand switches are notorious offenders. Just sayin.
    MJM - BeeCeeBeemers Motorcycle Club Vancouver B.C.
    '81 R80G/S, '82 R100RS, '00 R1100RT

  15. #15
    aapasquale
    Join Date
    Aug 2011
    Location
    Sag Harbor, New York
    Posts
    128
    Quote Originally Posted by happy wanderer View Post
    As per Paul Glaves suggestion why don't you hot wire the pump itself to check it. They are quite reliable normally and usually the problem is somewhere else. I looked at Doug Raymonds schematic.

    http://www.mac-pac.org/tech/electrical-diagrams/

    If you put 12 VDC on Pin 2 and ground on Pin 1 the fuel pump should spin. If it doesn't the pump may be your problem or the wiring to it etc. but if it does the interlocks need to be confirmed and you need to trace the voltage back to the fuse/relay box.

    Side stand switches are notorious offenders. Just sayin.
    hi Happy Wanderer--
    that test will be done tomorrow morning--seems the most direct to find out whether the pump is the problem or not--then
    i'll be troubleshooting from there--Today I take people on shark dives.....really

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •