Introduction: Oil Injection PWK28
First instructable I've made so hopefully it's understandable for the community! :)
Needed a carburetor for my Yamaha RX135-clone winter project,and had the PWK28 stowed away.
The PWK was not prepeared for oil injection so I wanted to see if I could make it...
It uses a 3mm id hose from the pump to the carburetor that is why I've used the parts I have in this instructable.
On other application different size of threads, connectors and hoses could apply!
Small chips can get in everywhere and is really sharp, so use PPE
* Safety glasses
* Vacuum to remove chips
* Clean carburetor (perfect chance to clean it well)
* Fittings - m5 thread with o-ring, to 4mm hose, i also added an elbow fitting. since I had the parts laying around.
It would be more ideal to just buy an 90 degree elbow...
* Center punch tool
* Batterydrill or drillpress with varying sizes of drillbits (I used 1,5 - 2,5 - 4,2mm)
* M5 thread tap
* Non-dissolving tissue, lubricant
Step 1: Mark and Center Punch
Draw a cross to mark where to drill.
I used a simple "spring charged" center punch.
Step 2: Drill and Threads
I filled the carburetor with a non-dissolving tissue to avoid chips falling into the carb
I used a small amount of wd40 (all kinds of lubricant would help, but my experience is that wd40 is excellent for drilling or grinding/milling aluminium), and held a vacuum close to get rid of all the small chips.
Drill the hole carefully, starting with a small drill and increasing in several steps.
After the hole have been drilled, make the threads with the tap.
Carefully remove the tissue making sure all the chips is removed.
Inspect the carb for any chips inside, then clean the outside, taking care that nothing falls into the starter/choke hole.
Step 3: Add Fittings for Hose Connection
Measured the pipe end on the threaded fitting and cut of 5mm to reduce the build height.
Make sure that you leave enough space to operate the quick release mechanism on the connector.
Screw the threaded fitting onto the carb and thighten just enough.
Since it has an o-ring it will seal up against the carburetor.
Mount the elbow.
Step 4: Finished
Recheck that the carburetor is clean for chips and other things.
The carburetor is now ready to be installed back into the bike, and connected to the pump.
Participated in the
First Time Author Contest 2018
Question 5 years ago on Step 4
Great instructable. How does the bike run with this mod? Did the original carb have a nozzle to take the feed to the centre of the venturi?
Answer 5 years ago
So far it has been working as it should.
I'm still trying to find the most suitable jet for this carburetor, on this motor.
The original mikuni had the oil nozzle after the piston, similar to my mod, only placed on the side.
You can see it on this carb: