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1Back to top Go down   Desperate.... K100RT 1985 - starting Empty Desperate.... K100RT 1985 - starting Wed Feb 07, 2024 1:53 am

Kendallsr

Kendallsr
active member
active member
It's been a journey and it's only been ten days since I bought the bike as a non runner and had been sitting for 15 years.....

New Oils all round.
New plugs
new petrol pump
Injectors removed and professionally cleaned and they all squirt well
Fuel moves in the tank and comes in & out via the respective fuel lines
Fuel filter new and facing the correct way.
Have 7 litres on fuel
Check earth under seat and the one by battery  - both cleaned
Spark plugs spark and connected in the correct order....

All lights works and brake light switches

Ignition on, all lights are on
Starter button pressed - fuel pump kicks in and the engine starts
with 2 to 5 second ds the engine stops
It doesn't like any throttle
removed the Throttle connection to the right of the injectors no change
Borrowed an ECU and tried this - no change.

Frustration and lots of swearing and still no further forward.

I'm not a mechanic just an bike enthusiast but in desperate need of some please... 

Thanks, Stephen

    

2Back to top Go down   Desperate.... K100RT 1985 - starting Empty Probs Wed Feb 07, 2024 2:38 am

daveyson

daveyson
Life time member
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One thing to try, have a look at the coils. They might be swollen or have cracks, then test them anyway. In the electrical section you will find a troubleshooting guide which includes testing the coils.

I've had that problem, if I persisted, it would eventually get going when the engine was warmer. From memory, I think there was no continuity between the HT terminals on my bad coils.

There were quite a few changes in 1985, yours is the  earlier version, in which the coils weren't too good.


__________________________________________________
11/1985 BMW K100RT (late model)  Vin. 0090567
 ~120,000 km
    

Dai

Dai
Life time member
Life time member
Also check the spark plugs to ensure they have thimbles/nuts/screw terminals on and that they are tight (the bit that screws on/off the top - new plugs don't always come with them) and take a look inside the plug caps to see if there's any copper oxide (green crud) in there. This is what I'm talking about:

https://www.ebay.com.au/itm/115501639940?hash=item1ae46f2904:g:s5UAAOSwux5YWP4l

Yes, it's ebay Australia but I couldn't find any Australian sellers.



Last edited by Dai on Wed Feb 07, 2024 7:28 am; edited 1 time in total


__________________________________________________
1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

92KK 84WW Olaf

avatar
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Next time you try to start it, keep your finger on the start button and see if it stays running while you are holding the button pressed.

The fuel pump gets its signal from two sources. The first is the start button but once the engine runs it comes from the Hall Sensors. If it stays running with the button pressed......check out your connection under the seat to the fuel injection control unit.

Now you mention the 7 liters of fuel. Having been down this road a few times caused by previous owners, if the fuel pump is not fully home in its mounting it runs out at about 13 litres......or a little over 7 litres left in the tank. My K1100 did this just recently. I just pulled the pump and reseated it correctly and problem solved. The early fuel pump mounts and dampers were not good, I have all mine swapped out. You should have a white plastic mount with one side slightly cut off so its straight. If not I would replace it with one.

So its possible the 7 litres of fuel is not actually enough to get the engine to run correctly.

Another high risk area on your K is the electrical plug into the tank. Check the terminals on the plug and if you need you can adjust them to make a better fit.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 51,800 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 63,390 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

92KK 84WW Olaf

avatar
Life time member
Life time member
Dai wrote:Also check the spark plugs to ensure they have thimbles on and that they are tight (the bit that screws on/off the top - new plugs don't always come with them) and take a look inside the plug caps to see if there's any copper oxide (green crud) in there.

Been there too. If you are using NGK D7EA or D8EA they dont come with these on them.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 51,800 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 63,390 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

Laitch

Laitch
Life time member
Life time member
Kendallsr wrote:It's been a journey and it's only been ten days since I bought the bike as a non runner , . . ..
What's the problem here? It's delivering as advertised. Laughing  

The mixture could be too lean. The Z-tube connection from the crankcase to the airbox could be cracked, the vacuum caps could be missing from each of three throttle bodies and the fourth's hose could be cracked. In addition all the intake manifold connections could be compromised. These defects allow unmetered air into the fuel mix—a condition that can cause difficulty starting and poor performance in general.

15 years could have allowed mouse housing developments in the air filter.

Don't get the impression that you're into a unique circumstance somehow. Yours is a shopworn tale, but it often has a happy ending, if you develop patience.



Last edited by Laitch on Wed Feb 07, 2024 10:56 am; edited 1 time in total


__________________________________________________
1995 K75 90,000 miles
    

Laitch

Laitch
Life time member
Life time member
One more caution. After the Brick's being idle for 15 years, the piston rings could be stuck and lowering compression. Remove the plugs and spray fogging oil or a small amount of motor oil into each cylinder then try starting.


__________________________________________________
1995 K75 90,000 miles
    

Kendallsr

Kendallsr
active member
active member
daveyson wrote:One thing to try, have a look at the coils. They might be swollen or have cracks, then test them anyway. In the electrical section you will find a troubleshooting guide which includes testing the coils.

I've had that problem, if I persisted, it would eventually get going when the engine was warmer. From memory, I think there was no continuity between the HT terminals on my bad coils.

There were quite a few changes in 1985, yours is the  earlier version, in which the coils weren't too good.
Thank you, as a new day begins here, my first task is to review the coils.  I'll let you know what I find.  Thanks

    

Kendallsr

Kendallsr
active member
active member
Dai wrote:Also check the spark plugs to ensure they have thimbles/nuts/screw terminals on and that they are tight (the bit that screws on/off the top - new plugs don't always come with them) and take a look inside the plug caps to see if there's any copper oxide (green crud) in there. This is what I'm talking about:

https://www.ebay.com.au/itm/115501639940?hash=item1ae46f2904:g:s5UAAOSwux5YWP4l

Yes, it's ebay Australia but I couldn't find any Australian sellers.
Thank you, will check today however from memory they all had the caps on top.

    

Kendallsr

Kendallsr
active member
active member
daveyson wrote:One thing to try, have a look at the coils. They might be swollen or have cracks, then test them anyway. In the electrical section you will find a troubleshooting guide which includes testing the coils.

I've had that problem, if I persisted, it would eventually get going when the engine was warmer. From memory, I think there was no continuity between the HT terminals on my bad coils.

There were quite a few changes in 1985, yours is the  earlier version, in which the coils weren't too good.
Have had the coils out.  They  have been unchanged and most likely untouched. 
Both good. 
Had the plugs out, they were a bit wet but cleaned them although were new 10 days ago. 
On a positive note, the bike starts and idles well for 20 minutes.  The fan came on. 
But still cannot throttle up. 
One question, the fuel pump runs continually once started and idling??
Thanks

    

firstle

firstle
Life time member
Life time member
flow meter flap stuck maybe ? the pump will run none stop

    

Laitch

Laitch
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Life time member
Kendallsr wrote:Have had the coils out.  They  have been unchanged and most likely untouched. 
Both good.
How were they determined to be good?


__________________________________________________
1995 K75 90,000 miles
    

firstle

firstle
Life time member
Life time member
have you a fully charged battery ? i have had a K that would start but not rev , battery was shot and took me a while to notice , simple things over looked  Crying or Very sad

    

Kendallsr

Kendallsr
active member
active member
Laitch wrote:
Kendallsr wrote:Have had the coils out.  They  have been unchanged and most likely untouched. 
Both good.
How were they determined to be good?
Had them out and tested with the multimeter... Readings on both coils the same.  Have a small clip of the bike running and testing of coils... Can't seem to load this here.  Thank for your response

    

Kendallsr

Kendallsr
active member
active member
firstle wrote:have you a fully charged battery ? i have had a K that would start but not rev , battery was shot and took me a while to notice , simple things over looked  Crying or Very sad
Have a new battery on order and hopefully here tomorrow... That would be a great fix!.  Thanks

    

Laitch

Laitch
Life time member
Life time member
Kendallsr wrote: Have a small clip of the bike running and testing of coils... Can't seem to load this here. 
What's usually done here is the member posts a public video on YouTube the posts the video's link in the thread.


__________________________________________________
1995 K75 90,000 miles
    

Kendallsr

Kendallsr
active member
active member
Laitch wrote:
Kendallsr wrote: Have a small clip of the bike running and testing of coils... Can't seem to load this here. 
What's usually done here is the member posts a public video on YouTube the posts the video's link in the thread.Feeling dumb.... Okay.  Thank you

    

18Back to top Go down   Desperate.... K100RT 1985 - starting Empty Clip of bike starting and idle... Thu Feb 08, 2024 2:21 am

Kendallsr

Kendallsr
active member
active member
Clip with bike starting... Have managed to get it to run longer but cannot throttle....
 
https://www.youtube.com/shorts/0GWo329hEJk?feature=share


Thanks

    

firstle

firstle
Life time member
Life time member
any fuel in the tank and have you changed the filter

    

Laitch

Laitch
Life time member
Life time member
Have you checked for debris restricting the air filter within the air intake box, and the snorkel that leads to it?


__________________________________________________
1995 K75 90,000 miles
    

Laitch

Laitch
Life time member
Life time member
Kendallsr wrote:Borrowed an ECU and tried this - no change.
Which ECU did you borrow and try—the ignition control unit or the fuel injection control unit?


__________________________________________________
1995 K75 90,000 miles
    

Kendallsr

Kendallsr
active member
active member
Laitch wrote:
Kendallsr wrote:Borrowed an ECU and tried this - no change.
Which ECU did you borrow and try—the ignition control unit or the fuel injection control unit?
Hi, the fuel injection control unit... The silver square box that sits above the battery.  Thanks

    

Kendallsr

Kendallsr
active member
active member
firstle wrote:any fuel in the tank and have you changed the filter
Thanks, yes changed the petrol filter with the new pump

    

Laitch

Laitch
Life time member
Life time member
Kendallsr wrote:Had them out and tested with the multimeter... Readings on both coils the same. 
I'm stuck here looking for clarity with quantification. What units on the multimeter were you measuring at the coils; from which terminals were you taking measurements and what were the readings?


__________________________________________________
1995 K75 90,000 miles
    

firstle

firstle
Life time member
Life time member
Thanks, yes changed the petrol filter with the new pump , thats the fuel filter not the one on the base of the pump , is that correct .

    

charlie99

charlie99
VIP
VIP
sounds like an afm issue 

crazy frog wrote a faults finding tutorial a while back specifically referring to afm measurements 

in some cases the electrical connector into the afm can corrode inside the unit as it touches the pc board holding the electronics board ...and often the sprung connection from the vane to the armature can also be near open circuit 
these issues can be repaired  with care and knowledge .

the reason for saying afm is because , i have seen many similar issues where the injection controller ..*(under seat computer )  has a minor heart attack at any movement of the vane wiper not connecting properly as the resistances the efi computer expects to see , just go wild when an open circuit appears , when it shouldnt 


good luck


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
1987 k100rs ########   "Red"  - (red sports rs TWB style )
1989 K100rt #009637   "Black Betty"  (naked rt ala Nigel , now sporting an rs main fairing )
    

27Back to top Go down   Desperate.... K100RT 1985 - starting Empty Success.... Fri Feb 09, 2024 3:00 am

Kendallsr

Kendallsr
active member
active member
Success comes to those that persevere.  Thanks to all those that contributed, I certainly learnt a lot about the bike which will hold me in good stead...

Always the basic that catches us out.  The first job I did when getting the bike was the service: new plugs, fuel filter, oil filter, oils and air filter.  Then onto new fuel pump, jets, etc.   After testing a few things I eventually got round to locating and getting to the fuel pressure sensor and 'Hall sensor".  However, when feeling around the back of the large black box above the air filter, I noticed it had adrift at the rear with a large air pipe not connected to the manifold (not sure this is the correct term) anyhow, managed to get my hand in there and with a bit of vaseline managed to get it back on and tighten up the large clip.... And that was the problem.  Bike, kicked into life and took some ten minutes to disperse all the oil I had put into the spark plugs.

Onto to the brakes now, new battery and new tyres and hopefully registration.

Thank you again for all the support.

Stephen

    

ReneZ

ReneZ
Life time member
Life time member
Hi Stephen, great to see you have it now fixed. No doubt great 'job satisfaction' Now ride the beast and have fun :-)

Cheers, Rene


__________________________________________________
Greetings from Florida Australia! Having a 'new' K     Surprised-o: 

Rene


BMW K100 - 1985 (0030029) Scotland Desperate.... K100RT 1985 - starting Rain
BMW K1200GT - 2003 (ZK01223) Florida
BMW K1200GT - 2004 (ZK27240) Australia
    

Dai

Dai
Life time member
Life time member
Kendallsr wrote:However, when feeling around the back of the large black box above the air filter, I noticed it had adrift at the rear with a large air pipe not connected to the manifold (not sure this is the correct term) anyhow, managed to get my hand in there and with a bit of vaseline managed to get it back on and tighten up the large clip.... And that was the problem.  Bike, kicked into life and took some ten minutes to disperse all the oil I had put into the spark plugs.
The bit with the air filter in it is the air box. The bit that the 90-degree intake connects to is the plenum chamber. You won't be the first one to have trouble with that.


__________________________________________________
1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

George_Pap

George_Pap
Silver member
Silver member
Kendallsr wrote:
daveyson wrote:One thing to try, have a look at the coils. They might be swollen or have cracks, then test them anyway. In the electrical section you will find a troubleshooting guide which includes testing the coils.

I've had that problem, if I persisted, it would eventually get going when the engine was warmer. From memory, I think there was no continuity between the HT terminals on my bad coils.

There were quite a few changes in 1985, yours is the  earlier version, in which the coils weren't too good.
Have had the same behaviour , found that the rubber manifold between air box and throttle bodies was teared / cracked next to the clamp . Fixed it with some rubber tape and waiting for the part to arrive . Give it a check and as already mentioned the Z breather hose inspection would be advisable 

    

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