Help wanted: DT 30 On a mission to smooth out idle

[TwoRivers]

Hello all and thanks to everyone who helped me on the orange spark thread.
Now after changing all the ignition parts attached to the 1987 Suzuki DT 30 motor it is starting reliably.
It stumbles and is inconsistent at idle but takes fuel and accelerates nicely to mid and wot. Runs strong at mid to wot.
This seems like a really versatile motor and since I have so much invested in it, I'd really like to smooth it out.
Here's what I've done so far:
Replaced diaphragms in fuel pump. New fuel tank, hose and connectors. Idle timing dead on at 2 degrees ATDC.
Seafoam treatment. Removed, cleaned air jet and passage with spray cleaner.
Compression 119 on both cylinders when warm.
I sprayed carb cleaner on the vacuum lines and no indication of a leak, lines look good. Fuel lines look good as well.
I realize I need to clean the carb but I have a few questions before taking it apart.
Can anybody source a carb rebuild kit for this motor? I can't seem to find one through Suzuki, just generic ones on ebay.
I think I really need a tach to fine tune this motor. So far everything has been done by ear and I don't hear all that well.
Any suggestions for a portable test tach or is Tiny Tach the way to go?
I'll try to post a video of the motor at idle. In the mean time if anybody can help me find a carb kit or gasket?
One more thought. The manual and stickers on the motor call for a 100:1 fuel mix. As per suggestions on this forum, I've been running 50:1 and I use Pennzoil Semi Synthetic oil. Will it even be possible to smooth out the idle with this mixture?
Many thanks
rob

 

[TwoRivers]

Re: Help wanted: DT 30 On a mission to smooth out idle

Come-on-Man!
You tellin me that not one of you geniuses know how to smooth out an old Suzuki single carb two stroke?
Your secrets are safe here.
Paging Philandjack.
rob

 

[99yam40]

Re: Help wanted: DT 30 On a mission to smooth out idle

you know what to do, clean carbs and adjust like specs call for

 

[TwoRivers]

Re: Help wanted: DT 30 On a mission to smooth out idle

you know what to do, clean carbs and adjust like specs call for

Gaskets will be here by middle of next week.
I'll clean the carbs and see where that leads.
What's you take on the fuel mix?
Thanks
rob

 

[99yam40]

Re: Help wanted: DT 30 On a mission to smooth out idle

either will run fine, it is the extra oil while it sits that helps protect the shiny internal parts during lay up that helps the most

 

[deejaycee_2000]

Re: Help wanted: DT 30 On a mission to smooth out idle

Keep it on 50:1 that is the safest!

 

[TwoRivers]

Re: Help wanted: DT 30 On a mission to smooth out idle

Got the main gasket and the bowl gasket today. Bought a gallon of GUNK carb cleaner and plan on cleaning tonight.
Any last minute tips or things to consider?
Motor has been smoothing out lately. Had it out Sat & Tuesday and she ran great and trolled pretty well. Still chugs a little and is running too rich? Seems like I dialed in the air mixture screw but it's still too rich. Any thoughts?
I'll post back after cleaning but appreciate any tips or suggestions.
thanks
rob

 

[James R]

Re: Help wanted: DT 30 On a mission to smooth out idle

If the motor will not respond to the idle adjustment the idle jet and associated bores are blocked.
I use the gunk product all the time and it works. You will still need to probe jets with fine steel wire to be sure they are clean. Carefully of course. Wash the Gunk of under the tap and blow clean and dry with compressed air, gently of course.

 

[TwoRivers]

Re: Help wanted: DT 30 On a mission to smooth out idle

If the motor will not respond to the idle adjustment the idle jet and associated bores are blocked.
I use the gunk product all the time and it works. You will still need to probe jets with fine steel wire to be sure they are clean. Carefully of course. Wash the Gunk of under the tap and blow clean and dry with compressed air, gently of course.

Thanks for your response.
I took the carb apart today to discover that the spring is missing from the air pilot screw. That would explain why it won't hold adjustment?
The carb and the jets are soaking in gunk cleaner right now.
The jets seemed open to air passage but looked dull and somewhat filmed.
The motor has actually been running pretty well but very rich at trolling speed.
When I removed the air pilot screw today to clean it up it was only a half a turn from seated.
BPM has the spring and screw in stock. Problem is that I want to fish this weekend so I'll have to rig a spring from a ball point pen or something till the replacement gets here. Any ideas?
I'm encouraged, thinking that restoring the spring along with the cleaning will smooth this baby out.
Onward with the mission. Thanks for your help. All tips and suggestions appreciated.
I'll report back when I get things back together.
rob

 

[TwoRivers]

Re: Help wanted: DT 30 On a mission to smooth out idle

Mission accomplished (sort of).
Ok. Just want to put the thread to rest.
Put the carb back together after soaking in gunk and spraying every orifice with seafoam spray, rinsing with water then drying with air. Replaced air mixture screw and new spring.
Took some trial and error to get the air/fuel mix dialed in.
This carb is really sensitive to any adjustment and I think the new air screw and spring allowed it to hold the settings better.
Anyways, the motor is starting, idling and throttling down very nicely.
I'd like to slow it down just a little more but I don't think I can do that without a tach/timing adjust. It's the best I can do by ear and I'm happy for now.
Thanks for all who responded and to all those who viewed the thread.
rob