• The software has been updated. Message Travis if you find any issues.

Pressed in pilot jet removal

sdew99

CB750 Enthusiast
Messages
55
Reaction score
12
Points
8
Location
Nova Scotia Canada
I've seen reference on here to people using machine screws to remove the pressed in pilot jets.
What size screws are people using? Any specific material screws?
Thanks!
 
1706829776249.jpeg
1706829815585.jpeg
1706829855765.jpeg
1706829879364.jpeg


Use a 2-56 tap to make threads into the pilot jet. That tap size is close enough to start in the hole. Just thread down 3 or 4 threads. Some people use a sheet metal screw and screw it part way into the jet and then pull on the screw with a pair of pliers. The threaded way is better in my opinion because once the threads are there it is easy to pull the jets out if you have to do it again down the road. Your choice of methods.
 
View attachment 15003View attachment 15004View attachment 15005View attachment 15006

Use a 2-56 tap to make threads into the pilot jet. That tap size is close enough to start in the hole. Just thread down 3 or 4 threads. Some people use a sheet metal screw and screw it part way into the jet and then pull on the screw with a pair of pliers. The threaded way is better in my opinion because once the threads are there it is easy to pull the jets out if you have to do it again down the road. Your choice of methods.
Alright thank you!
 
View attachment 15003View attachment 15004View attachment 15005View attachment 15006

Use a 2-56 tap to make threads into the pilot jet. That tap size is close enough to start in the hole. Just thread down 3 or 4 threads. Some people use a sheet metal screw and screw it part way into the jet and then pull on the screw with a pair of pliers. The threaded way is better in my opinion because once the threads are there it is easy to pull the jets out if you have to do it again down the road. Your choice of methods.
1000011006.jpg

Success... what can be used to clean the small hole in the middle? E string seems too big
 
Get a piece of automotive type wire a cut a piece 3-4 inches long and then pull out a few strands. Or use welding tip cleaners if you have any.
 
Boil it with a bit of dawn? Not so serious here. That looks nasty, did you do any soaking, spraying or cleaning on it before you pulled it out? Just curious.
 
Last edited:
Boil it with a bit of dawn? Not so serious here. That looks nasty, did you do any soaking, spraying or cleaning on it before you pulled it out? Just curious.
Yeah.. ultrasonic cleaned with simple green and dawn and then carb cleaner. And still that dirty. Having a real hard time getting the centre hole cleaned out now.
 
Yeah.. ultrasonic cleaned with simple green and dawn and then carb cleaner. And still that dirty. Having a real hard time getting the centre hole cleaned out now.

unfortunately, ultrasonic cleaners aren't always able to make things clean. for this type of stubborn clog, I have used single strands of a brass wire brush and a pair of needle nose pliers. don't use a steel wire because you run the risk of enlarging the orifice. if the clog is caused by varnished fuel, try soaking it in straight acetone. Acetone dissolves varnished fuel.
 
unfortunately, ultrasonic cleaners aren't always able to make things clean. for this type of stubborn clog, I have used single strands of a brass wire brush and a pair of needle nose pliers. don't use a steel wire because you run the risk of enlarging the orifice. if the clog is caused by varnished fuel, try soaking it in straight acetone. Acetone dissolves varnished fuel.
Finally got it with the brass wire. Wow is all I can say... frigging stubborn.
 
Finally got it with the brass wire. Wow is all I can say... frigging stubborn.
Just looked at your photo again, I would definitely recommend an acetone soak. that looks like nasty old varnish. glad to hear you got it though. just be careful when you press it back in.
 
Just looked at your photo again, I would definitely recommend an acetone soak. that looks like nasty old varnish. glad to hear you got it though. just be careful when you press it back in.
All of the centre holes of the pilot jets were blocked off.. how much of a difference should it make at idle having those cleaned up? I would think it should be significant?
 
All of the centre holes of the pilot jets were blocked off.. how much of a difference should it make at idle having those cleaned up? I would think it should be significant?
If all were clogged, I would suspect your bike didn't idle at all. If it still ran, its possible they weren't completely clogged. But yes, you would 100% see a significant difference if that were the case. This jet is metering how much fuel makes it to your mixture screw.
 
If all were clogged, I would suspect your bike didn't idle at all. If it still ran, its possible they weren't completely clogged. But yes, you would 100% see a significant difference if that were the case. This jet is metering how much fuel makes it to your mixture screw.
Ok that's what I tonight. So, that jet supplies fuel to the mixture screw, but what about the two transfer ports right behind the throttle plate? Does the slow jet supple those as well or are those off of a different circuit?
 
Back
Top