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1987 k75 sat 10 years won't start

acehosedme

New member
I recently (4 months ago) bought a 87 k75 that sat for 10 years with fuel in the tank. i replaired the holes in the tank, bought a new $fuel pump, filter, hoses and pump mounting rubber. I put in a fully charged battery and the motor turns over but will not start. I have no cvlue how fuel injection works. What is the order of attack to get this bike running? What do i look for?

Thanks.
Bob
 
Bob,
I think you are going to need to clean or replace all three injectors too. In addition to the injectors, get new plugs and have the fuel rail cleaned. Once you get all the old residue out, I'm betting it will run great.

Mick
 
10 year layup

what Mick said, you'll definitely need to pull the injectors
and clean the fuel rail. If you have time you may be able to clean
the old injectors but if they look like the ones that came out
my k100 after it sat up 7 years its not worth it. the ibmwr
web site has some listings for alternative (cheaper) injectors.
You should flush the brake fluid too, i imagine the rear m/c is toast
by now.

Best,

Eric
 
All your fluids, all your filters, and be ready to put new rubber on it before you do more than go around the block. You might have some electrical bugs. Don't worry- it will be worth it. Congratulations!
 
I cleaned the fuel rail, i didn't see any residue in it. How do you go about cleaning the injectors them selves? I re-installed the injectors and eveidently one of the o-rings was pinched enough to leak fuel . I also put in new plugs. It didn't start , could one injector leaking fuel cause the motor to not start at all?
Thanks.
\Bob
 
Bob,
The injectors get cleaned by an ultra-sonic cleaner usually. The Bosch Injection guys that work on big trucks usually have a way to clean and flow test the injectors. The cheaper replacements on the IBMWR site tech info would be a better alternative. You could have as much in cleaning as in replacing. :confused: I think Eric already suggested the alternate injectors.

Ford injectors
Part # F1ZZ 9F 593 B
Price around $75 each.
Simple plug and play

Above data from Greg Hutchinson


One O-Ring leaking, at the fuel rail? Have you tested the pressure at the rail? I believe the K75 had the pressure regulator plumbed off the end of the fuel rail like the 1100(?) If your pressure is below 2.6 bar It isn't gonna run too well even if it does start. You could try blocking off the pressure regulator just to see if it starts.

Do you have good spark? Pull the plugs and then put them back in the plug lead and ground the plug body. You sould see good blue sparks at all the plugs.

Don't give in....It WILL be worth it. :clap

Mick
 
Mick,
Would removing the fuel rail with the injectors and electrial connectors attahced and cranking the motor over do any harm? Would this be an effective test of the injectors to see if they at least spray fuel? I still haven't done the old ground out the spark plug thing yet, but will do this afternoon.
Thanks
Bob
 
Bob,
If you can keep the fuel flow AWAY FROM SPARKS AND HEAT it would be no problem. You can even watch the spray pattern. Just have a good way to collect the fuel.

Should only take a few seconds to verify the spray pattern.

Mick
 
Mick,
I get good spark from the one plug I checked. I removed the fuel rail and turned the motor over, only one of the injectors sprayed anything. That being the one closest to the rear, the same one that leaked fuel before. It looks like I need new injectors or get these cleaned, eh?
Thanks for your help.
Bob
 
Bob,
Yep, you are ready for a total cleaning/flow testing or new injectors.

Mick
 
Everyone,
This morning I got 3 old, greasy, dirty injectors off of a Ford to see if they would at least start the bike. They did. Good, yes. It was hard starting and I had to put in another battery after I wore the first one down. Once it started I let it run for about 4-5 minutes and it kept blowing smoke, white smoke. Should this be expected after 8-10 years of not running? Now I guess I find someone who'll clean the original injectors I hope for a lot less than new ones. Thanks for everyone's help!
Bob
 
Bob,
Congratulations!! :clap :clap :clap

I would warm it up a little and change the oil and filter. Run it another 300-500 miles and do it again.
If it were me, I'd use Mobil-1 for the second oil change and keep using it. The Mobil synthetic is very good at cleaning the sludge out of old engines.
The oil smoke (white) could be stuck rings or just some oil residue in the cylinders. It should run with a clean exhaust after 5 minutes or so.
If the injectors match the number given above, you just might clean them up a little and use them till the originals get cleaned.

Mick
 
Last edited:
cleaning the hard way

Well you seem bent on this method so you might want
to search the archives at IBMWR. I'm pretty
sure a fella from down under had a DIY guide
using a car battery and a piece of hose,
and pulsing the injector with the hose attached and filled with varsol. I would still opt for remfg injectors unless
the bottom line is at hand
 
today's k75 question:
I rode the bike today to get plates, insurance and a fwe other stops before ghetting to work. grand total is 18 miles. I tried to go home and it died about 8.5 miles into a 13 mile ride. It is sitting in soemone's parking lot right now. It seemed the more I rode it the more the motor seemed to die on acceleration. The motor just stopped running altogether as if it wasn't getting any fuel, I have about 4 gallons of premiuim in the tank. I put in a new fuel pump and filter and strainer for the pump, and the tank was bone dry when i put the new pump in. After the bike died I tried to star tit again and i can hear the fuel pump working.
My question is: WHat bonehead thing am I overlooking here to get this running again? It has oil showing in the sight glass. I did look at that . other than the brake fluid needing to be changed the bike feels fine.

Bob
 
ok I admit it, I'm a moron. I didn't tighten the hose clamps on either side of the fuel filter enoigh so the hose just plain blew off. Once I did that things seem to be much better. Gee, I wonder why.
 
Nobody is born knowing this stuff, you're doing fine. Even the (apparently) simplest oversights, get you at times. Roll with the punches, keep a sense of humor (perspective) & enjoy one of the best motorcycles ever built. I've been through this tour MANY times & I'm still trying to take said advice (easier said than done).
Carb cleaner is capable of degunking injectors. I've also taken a #0 phillips driver to unstick a pintle (not recommended, but it worked). As for checking injector function, I pull the rail & injectors & put them over a large piece of corrugated board. I leave the plugs in & coils attached (keep electrics ok). Spin it over a few times & the injector pattern will show on the cardboard; looking as mist, fine atomization is good.
 
there is an outfit in Indianapolis In that can do wonderful things with clogged injectors. Linder electric. Much cheaper than new injectors and quite effective. Talk to Doug Garriot
 
Thanks for the info. I did swap what I had with a guy in Tennessee for 25.00 each excchanged. |The bike runs now but rough.
Bob
 
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