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Help with '86 K75 Fuel Injectors

POGGI

New member
What is the procedure for removing the fuel injectors on a '86 K75C? I've removed the fuel rail bolts, then I .....?

Thanks in advance.

John Ranalletta
 
The fuel rail is clipped to each injector. You can pull all three of them out while connected to the rail, or remove each clip (the clips slide off to the side), and pull them individually. I like to remove them individually.

Squirt WD40 around the perimeter on the injector, grab the injector with your fingers, and slowly wiggle out. Make sure you put them back in with new o-rings on the body and the tip.
 
Also take some compressed air and blow the area clean, especially around the injectors, so nothing falls into the hole when you pull the injectors. Don't forget your eye protection. :stick
 
Injectors...

jdiaz said:
Don't forget hearing protection when using compressed air too, right Bob? :laugh

Jon..

Looks like the injectors are toast as they're not passing gas...

Are you aware of substitutes for the 280 150 210?

Thanks,

John
 
POGGI said:
Jon..

Looks like the injectors are toast as they're not passing gas...

Thanks,

John

John: If I remember correctly, this bike hasn't been run for about ten years, right?

Anybody: Can injectors get clogged, just like carbs, and can they be cleaned out?

Don
 
djw said:
John: If I remember correctly, this bike hasn't been run for about ten years, right?

Anybody: Can injectors get clogged, just like carbs, and can they be cleaned out?

Don

Some say that if you put a nine volt battery (maybe requires more AH than a 9 volt battery...) on them and leave them in carb cleaner, they may unstick.
 
I had a similar problem with my K100. While I had it disassembled for paint, I pullled the throttlebody assembly off to have the rubber intake connectors and fuel pressure regulator replaced. This left the fuel rail open to the atmosphere. Shortly after disassembly I ruptured 2 discs, had surgery and the bike sat for about 8 months. When I finally got everything back together, the injectors were stuck from the varnish left by the evaporated fuel. I pulled the injectors and took them to a diesel injector repair shop. They were cleaned and tested for $8 each. Very reasonable, quick (1 day), and much less work than trying to soak and clean them yourself.
 
One Way...

Same Situ: K75 w/stuck injector pintles.
1> remove the rail & injectors as a whole
2> put a Big piece of cardboard between them and the engine
3> attempt to start engine for ~2 seconds

I should've see a fan pattern of ~100 degrees and ~3" straight away from the nozzle. I had 1 out of 3 good.
What follows is Not Recommended by many, but I figured why not....
I posed that the varnish/goo that dries & sticks the pintles is just a really thin layer, and once broken free, fresh gas Should rinse it clean (SWAG).

So I...
a> used the blunt tip of a phillips screwdriver and Gently pushed the pintle in.
b> a fine mist of gas came out until the rail pressure dropped off.
c> ran the starter to check for proper patterns

IIRC, it took a couple of a->c loops to clear them out, but that engine has run just fine until end of season. Come spring will be another marker of how well this worked. If this sounds crazy, it won't draw a news conference with My name. G.H... <<<)))
 
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