So I pulled these plugs out after a little riding mostly wot in a field. How do they look to you? 91 octane 40:1
Its a jdx8 with a Tillotson HD 14a carb
Rode it on factory HD settings of 1 turn out for high and low speed.
In the picture they are two different plugs as I tested one set then another to see the difference. Both sets look the same.
Rich, good , or lean??
Rich, good , or lean??
- Attachments
-
Re: Rich, good , or lean??
They are a nice tannish color which is what you'd like to see. So first indication is it's good. You should have the KEC 440/22 Reed Valve. I'm quite cautious with these because just slightly lean could mean disaster, but your plugs look pretty good. I'm just guessing, but the one on your right is likely the Mag cylinder, and the one on the left is PTO?
Question: What plugs are you running? NGK BR9ES? Champion RN2? Also, what gap do you have them set?
How did the top end feel? Was it pulling like you think it should have, or was there any part of your throttle range that seemed lacking in power? Just curious. Does your idle setting seem correct now?
Jason
Question: What plugs are you running? NGK BR9ES? Champion RN2? Also, what gap do you have them set?
How did the top end feel? Was it pulling like you think it should have, or was there any part of your throttle range that seemed lacking in power? Just curious. Does your idle setting seem correct now?
Jason
1975 John Deere 800
1975 JDX8 (VC Finisher 2019)
1976 440 Cyclone (VC Finisher 2022)
1974 El Tigre 440 (Sold)
1996 Arcitc Cat 440Z
1975 JDX8 (VC Finisher 2019)
1976 440 Cyclone (VC Finisher 2022)
1974 El Tigre 440 (Sold)
1996 Arcitc Cat 440Z
Re: Rich, good , or lean??
To be honest I forget which plug came from which side.
They could both be from the same side, I tested two sets of plugs this is one of each of the sets both looked the same
I'm pretty sure the right one is a br9eya and the one on the left is a champion rn2 or
During this ride I shredded the belt because it was the wrong belt sled came with 3 belts all different sizes turns out the one on it was only an inch wide and 2" too long..
Soo with the new belt this thing is actually scary fast n lifts the skis lol.
As for my idle issue it's still fouling plugs on idle if left too long.
It will idle good for a bit then die down I can give it some throttle and clear it up. But if I set my idle set screw in any higher it still will foul the plugs. Low speed screw doesn't seem to find an actual sweet spot. If I blip the throttle from 0-100 it bogs for a second till rpm climbs then all is smooth. Is fine if I do it slowly.
Did the carb gaskets and diaphragms. No fuel in the pulse line now. May have to take it apart for another cleaning maybe take the Welch plugs out this time.
They could both be from the same side, I tested two sets of plugs this is one of each of the sets both looked the same
I'm pretty sure the right one is a br9eya and the one on the left is a champion rn2 or
During this ride I shredded the belt because it was the wrong belt sled came with 3 belts all different sizes turns out the one on it was only an inch wide and 2" too long..
Soo with the new belt this thing is actually scary fast n lifts the skis lol.
As for my idle issue it's still fouling plugs on idle if left too long.
It will idle good for a bit then die down I can give it some throttle and clear it up. But if I set my idle set screw in any higher it still will foul the plugs. Low speed screw doesn't seem to find an actual sweet spot. If I blip the throttle from 0-100 it bogs for a second till rpm climbs then all is smooth. Is fine if I do it slowly.
Did the carb gaskets and diaphragms. No fuel in the pulse line now. May have to take it apart for another cleaning maybe take the Welch plugs out this time.
Re: Rich, good , or lean??
When I did the gasket kit I adjusted the falcrum arm down a bit as it was raised slightly.
Before my fuel line was full all the time as with my return line.
Now my return line is full and my supply line is half empty below the filter. The longer I run it the more it seems to go down very slowly.
I'm thinking maybe the falcrum arm is now set too low and not supplying enough fuel?
As seen in the video I've got a bog from 0-100% throttle you can see the gas in the line move when this is done. If i rev slowly it's fine.
Also, if I put my hand over the intake and rev 0-100% it revs fast without a bog when I let off the throttle and my hand is still over the intake it chokes out
So I'm thinking it's not supplying fuel fast enough and probably running lean under WOT.
Can't do a proper plug test in the alley cause she's too fast
Probably only one second to get to the end of the block or so it feels like it lol. I've also got a bit of hesitation WOT mid range but it overcomes it. I'm thinking still a fuel issue.
https://youtu.be/aWfs5XCEGUo
Before my fuel line was full all the time as with my return line.
Now my return line is full and my supply line is half empty below the filter. The longer I run it the more it seems to go down very slowly.
I'm thinking maybe the falcrum arm is now set too low and not supplying enough fuel?
As seen in the video I've got a bog from 0-100% throttle you can see the gas in the line move when this is done. If i rev slowly it's fine.
Also, if I put my hand over the intake and rev 0-100% it revs fast without a bog when I let off the throttle and my hand is still over the intake it chokes out
So I'm thinking it's not supplying fuel fast enough and probably running lean under WOT.
Can't do a proper plug test in the alley cause she's too fast
Probably only one second to get to the end of the block or so it feels like it lol. I've also got a bit of hesitation WOT mid range but it overcomes it. I'm thinking still a fuel issue.
https://youtu.be/aWfs5XCEGUo