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Smashed Spark plug...

Did valves... went to do throttle body sync... very rough...would barely idle... read a bunch on throttle sync... loosened both throttle cables (yes i know you do not have to touch the left, but thought i would start from scratch)...set idle BBS to 2 turns out... would not even start / idle... just some coughing and sputtering... seems like it would only start and try to run if given gas...
Any suggestions? seems like nothing i did in my whole head disassembly made any difference.. not a happy camper
 
Did a motronic reset... started bike ...would only run if throttle applied...but then after a few seconds, held at constant rpm 2k-3k, would fade and stall, even though the throttle held at constant.
Emptied tank and will get new gas... and will try to do a fuel injector cleaning...
Thinking possible fuel pump problem?
Have to research how to test fuel pressure..
 
Pulling out the Fuel Pump setup was fun... of course one of the 8 nuts did not come off because the bolt stripped out and i had to cut the nut off with a dremel... cant use that bolt... but i hope the other 7 will apply enough pressure to keep it sealed , as i cannot remove the bolt to put in another and have no clue as to what might fix that..
Back washed the pump and it seemed to be working ...but i have already ordered a replacement for 70$..so i will keep it as a spare..
It seems like the elbow hose might have developed cracks ( i read that it often does)..so there might be fuel leakage there under pressure and that might be causing the problems.
I made another order from EME for the fuel pump hose...
https://www.euromotoelectrics.com/product-p/fp-hosekit.htm
and the Vibration Dampener had also disintergrated:
https://www.euromotoelectrics.com/product-p/fp-231damp232.htm
also one end of the fuel sock had come opened, so was not doing its job, but that comes with the fuel pump, which i got from High Flow Fuel off of Ebay:
https://www.ebay.com/itm/BMW-EFI-Fu...2004/160816740988?fits=Make:BMW|Model:R1100GS

Fun!
 
Soooooo.....
Replaced the Fuel pump, and keeping the old one for a spare.
Did a "fix" for the stripped bolt, put about 4 washers under the nut...should be good.
Oh yes...when replacing the fuel pump, make sure that you get a new rubber o-ring for the mounting plate....mine was getting a little cracked but seems to be sealing the gas in fine.
Started the bike up ...it did start ... but would not idle and would only keep going with some throttle.
died after a few...
ignition again, but no go...no idle no run period... would turn over but no run... thought i might have flooded, as i did smell some gas .
Let it sit a while charging the battery and tried starting again...again, turned over , but no go!
Arrrrrgggg!
Did the same again, over night and tried again....no go...
Very dejected!
Hmmmm..... thinking , reading...web researching....
One last try ...Motronic reset again... pulled #5 fuse and disconnected the battery for a few hours...went in to work, push fuse , connect battery.....turn ingnition key one click, roll throttle on full, off...three times... turn off ignition key...
Buttoned up..
Ignition and.... Takeoff!!!!!
Revved to 3k and let engine heat up...stayed at idle...
turned off bike and it started again! Went on a ride down the road.... rough engine, but i will take that for now..
Still have to balance the carbs.
I believe with the retensioning of the throttle cables and i though i read somewhere, about disconnecting the fuel tank, that the motronic needs to be reset to sense the throttle plate positions..
So for now it looks like i have a working bike again!:dance
 
Ok..need some advice..
Went outside and tried to start the bike to do the throttle body balance..
No start... just like before...just turn over, turn over, trying to catch..
Tried this two separate times..no go
Third time it finally catched and i bring it up to 3k rpms to warm it up..
while i am doing this i notice the exhaust pipe coming out of the right (sitting on the bike) head is turning red... not the left...
I bring it down to idle and hook up the manometer(homemade) and the liquid is flowing to the right cylinder... pretty fast...tried to open up the BBS and did nothing...finally had to disconnect from the throttle bodies before fluid reached it.
So hard starting... Very hot exhaust... low pressure from throttle body... Valve problem?
I have run out of ideas
Help!
 
Do a compression check. Sounds like you are running on one cylinder. Might have a chip in a left side valve.

Thats what i was thinking...one cylinder..
Need to check if sparking on that side
"chip in left side valve"? Just took apart both sides and cleaned... valves seemed to be sealed when closed
 
Smashed Spark plug

Yes, back to the basics. It ran well before it was taken apart so it can and will run again.

Compression, Spark, Fuel, Air.

Compression, a stated it is great idea to check both sides. If it is way off then the valve adjustment is suspect.

Spark, remove both plugs so it will spin over easily. Check by grounding each plug and watching each plug for bright blue spark or I like to put a strobe timing light on each plug wire and watch that it blinks each time it should spark. Make sure you have good plugs that aren't soaked with gas. Also, must have good ground on the plug.

Fuel, check that you are actually getting the correct fuel pressure and fuel flow on the return fuel line. If pressure or flow is low, did you replace the fuel filter along with all the in-tank fuel lines?

If possible remove the fuel injectors, one at a time, but leave connected. Pointing each away from the bike and verify each has a good spray pattern as the engine is turned over. A fuel injector could be plugged or mal functioning or the electrical connection could be bad.

If it has compression, spark and fuel, I would focus on the throttle body sync as this was probably changed when the throttle cables were loosened.

Just my thoughts of how I might proceed.
 
I'm sorry to be the one to say it, but this sounds suspiciously like the right side throttle cable unseated issue.

Probably present since before you dug into the tank (posts 42&43). But it can't hurt to have renewed the fuel pump plumbing (except for the stripped bolt...).
 
I'm sorry to be the one to say it, but this sounds suspiciously like the right side throttle cable unseated issue.

Probably present since before you dug into the tank (posts 42&43). But it can't hurt to have renewed the fuel pump plumbing (except for the stripped bolt...).

Nope! Had that before , and always check cable now!
 
Yes, back to the basics. It ran well before it was taken apart so it can and will run again.

Compression, Spark, Fuel, Air.

Compression, a stated it is great idea to check both sides. If it is way off then the valve adjustment is suspect.

Spark, remove both plugs so it will spin over easily. Check by grounding each plug and watching each plug for bright blue spark or I like to put a strobe timing light on each plug wire and watch that it blinks each time it should spark. Make sure you have good plugs that aren't soaked with gas. Also, must have good ground on the plug.

Fuel, check that you are actually getting the correct fuel pressure and fuel flow on the return fuel line. If pressure or flow is low, did you replace the fuel filter along with all the in-tank fuel lines?

If possible remove the fuel injectors, one at a time, but leave connected. Pointing each away from the bike and verify each has a good spray pattern as the engine is turned over. A fuel injector could be plugged or mal functioning or the electrical connection could be bad.

If it has compression, spark and fuel, I would focus on the throttle body sync as this was probably changed when the throttle cables were loosened.

Just my thoughts of how I might proceed.

Checked for spark... left side was a pretty weak spark... right side much stronger... both were yellow...not the bright blue recommended....
My next thought is to replace the SPARK PLUG WIRE SET :

https://www.euromotoelectrics.com/Ignition-Wire-Set-BMW-R-Oilhead-p/bmw-wsr641.htm
 
Certainly having one side spark much stronger than the other is consistent with the thought that one cylinder is not functioning correctly, which is causing it not to start and run poorly when it does start. At the very beginning of the thread the bike seemed to run ok, other than the smashed plug. Somehow during the process of the repair something changed affecting operation. It is feasible that a plug wire could be damaged in removing and reinstalling causing the weak spark. Prior to ordering you might want to consider, FIRS, make sure the battery is fully charged and then check the spark quality again. SECOND, If the spark plug being tested has a good ground, you should get a good blue spark. If you don't get a blue spark on at least one plug possibly one of your frame ground wires loosened up or the battery is low on voltage. THIRD, If you still have one side weak and the other good you could swap the plug wires to opposite side of the coil. If the weak spark follows the wire you have verified the bad wire. If the weak spark is still on the same side then I think it would be a bad coil internally. If the wires have never been changed, new wires are probably worth the investment but might not fix the problem. Just ideas for consideration.
 
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