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89mastercraft
05-20-2013, 06:25 PM
Hello All..

I'm looking for someone who mad have had the same problem I am going through. For the second Summer in a row my boat will not hot start.

It's a 1993 Mastercraft Prostar 190

- 351 indmar engine
- New plugs
- New wires
- Ordering a new distributor cap today
- Holley carburetor

The boat runs and drives fine on initial start up, but once it has ran if you cut it off.. it will NOT start back up.

Any help is HIGHLY appreciated. Thanks guys!

thatsmrmastercraft
05-20-2013, 06:48 PM
You have some of the basics taken care of. Here are a few more to work through:

1. Replace the dist. rotor too.
2. Battery connections should all be cleaned, have a little dielectric grease applied and reconnected.
3. Verify that the timing is set to spec.
4. Fuel quality can come into play here. If you are not going through your tank on a bi-weekly basis, adding Stabil or similar will make a difference.
5. Change fuel filter and water seperator filter.
6. Thoroughly clean spark arrestor.

If all these things don't resolve the issue, I would have the battery and starter tested. If those both check out, it is probably time for a carb rebuild.

89mastercraft
05-20-2013, 07:15 PM
You have some of the basics taken care of. Here are a few more to work through:

1. Replace the dist. rotor too.
2. Battery connections should all be cleaned, have a little dielectric grease applied and reconnected.
3. Verify that the timing is set to spec.
4. Fuel quality can come into play here. If you are not going through your tank on a bi-weekly basis, adding Stabil or similar will make a difference.
5. Change fuel filter and water seperator filter.
6. Thoroughly clean spark arrestor.

If all these things don't resolve the issue, I would have the battery and starter tested. If those both check out, it is probably time for a carb rebuild.

The highest octane we have available around my area is 93 and I always use that, but I will add some fuel stabilizer.

Battery terminals are clean and good to go.

What is factory timing?

Where is the spark arrestor located, also the water separator filter?

Thanks. I just wanna get this thing running right and have a good time this summer... Two years in a row I have had this issue

ricford
05-20-2013, 07:38 PM
If I had to guess, I would start with the carb/fuel filters. Sounds like a gas issue to me. You may not have a water separator filter, my 96 does not. The spark arrestor, or flame arrestor, is on top of the carb, looks like an air filter. Search the threads for rebuilding your Holley carb.

ricford
05-20-2013, 07:40 PM
The water separator looks like an oil filter but it will be mounted to the side of the engine bay. You could try running some seafoam through the fuel system. Worked wonders on a rough running seadoo I had.

Spork
05-20-2013, 07:43 PM
...........

ncgreg
05-20-2013, 10:00 PM
Lots o good advise here. Lots of possibilities, so you basically are going to have to figure out if you are geting spark when this developes or if it is a fuel flooding or lean out issue. Next time out when it acts up, take a spare spark plug or spark gap tester, hook it up, ground it, try starting it while you are watching for spark. If you have it, it is not ignition, start looking for fuel issues.

Before ya shut it off, let it idle for several minutes, and watch/smell the exhaust. If it is thinking about flooding out you will see black soot in the water or smell CO.

Couple comments, you likely have a 4010 holly and the floats are prone to cracking in that carb which eventually will cause them to sink. When that happens you will get mild to severe flooding and no way will it start. Watch the downturned carb venturi pipes, verify there is no raw gas coming out running ino the carb throat. If so, check the needle valvs and floats for cracks. Floats cost $28 each from Holly, dont ask why I know. Also check nothing is causing the choke to be on.

Another simple thing to check is the pcv valve. When they go bad, some times they leak, sometimes they dont and when they are leaking will cause lean rough running condtion that has you pumping the throttle a bit or hard starting. Check it by blocking the suction line, to see if idle improves.
Good luck!

east tx skier
05-20-2013, 10:31 PM
If you have the stock dual feed Holley 4010 carb, replace it with a 4160 and your hot stall poor idle issues will be a thing of the past. Been there. Professional rebuild did nothing to alleviate it for me. New 4160 was the ticket.

cal69
05-21-2013, 12:55 PM
This does sound fuel related and yes, the 4010 Holley is not the best performing. I just made the switch to a 4160 and am happy so far.
Another thing to check is the spark. I chased a cut out and no-restart condition when I bought my boat last year. Thought it was surely fuel, rebuilt the carb and it did not change. Would cut out after running for 30-60 minutes and not restart until it sat for 20 mins. Figured out it was a bad coil after it stalled and when I put my hand on the coil it burned me. Cooled it down and the boat immediately restarted. Replaced coil and has been perfect since. Just something to consider.

cbryan70
05-21-2013, 01:01 PM
Is the choke working properly? Once hot see where the choke flap is. Is it open or closed. Once hot it should be open I beleive.

My boat is odd and when its hot and wont start I will sometimes have to close the choke to get it fired up.

89mastercraft
05-22-2013, 01:50 AM
If I had to guess, I would start with the carb/fuel filters. Sounds like a gas issue to me. You may not have a water separator filter, my 96 does not. The spark arrestor, or flame arrestor, is on top of the carb, looks like an air filter. Search the threads for rebuilding your Holley carb.

The water separator looks like an oil filter but it will be mounted to the side of the engine bay. You could try running some seafoam through the fuel system. Worked wonders on a rough running seadoo I had.

10 BTDC is base factory timing setting

Does the boat crank slow when hot hence the no start or does it crank normal just does not fire off? Look at the back two barrels of the carburetor when hot and see if fuel is dripping. Might be time to rebuild the carburetor.

Lots o good advise here. Lots of possibilities, so you basically are going to have to figure out if you are geting spark when this developes or if it is a fuel flooding or lean out issue. Next time out when it acts up, take a spare spark plug or spark gap tester, hook it up, ground it, try starting it while you are watching for spark. If you have it, it is not ignition, start looking for fuel issues.

Before ya shut it off, let it idle for several minutes, and watch/smell the exhaust. If it is thinking about flooding out you will see black soot in the water or smell CO.

Couple comments, you likely have a 4010 holly and the floats are prone to cracking in that carb which eventually will cause them to sink. When that happens you will get mild to severe flooding and no way will it start. Watch the downturned carb venturi pipes, verify there is no raw gas coming out running ino the carb throat. If so, check the needle valvs and floats for cracks. Floats cost $28 each from Holly, dont ask why I know. Also check nothing is causing the choke to be on.

Another simple thing to check is the pcv valve. When they go bad, some times they leak, sometimes they dont and when they are leaking will cause lean rough running condtion that has you pumping the throttle a bit or hard starting. Check it by blocking the suction line, to see if idle improves.
Good luck!

If you have the stock dual feed Holley 4010 carb, replace it with a 4160 and your hot stall poor idle issues will be a thing of the past. Been there. Professional rebuild did nothing to alleviate it for me. New 4160 was the ticket.

This does sound fuel related and yes, the 4010 Holley is not the best performing. I just made the switch to a 4160 and am happy so far.
Another thing to check is the spark. I chased a cut out and no-restart condition when I bought my boat last year. Thought it was surely fuel, rebuilt the carb and it did not change. Would cut out after running for 30-60 minutes and not restart until it sat for 20 mins. Figured out it was a bad coil after it stalled and when I put my hand on the coil it burned me. Cooled it down and the boat immediately restarted. Replaced coil and has been perfect since. Just something to consider.

Is the choke working properly? Once hot see where the choke flap is. Is it open or closed. Once hot it should be open I beleive.

My boat is odd and when its hot and wont start I will sometimes have to close the choke to get it fired up.


The engine has the replacement 4160 carburetor, but the 4 barrel is not working right now. (not hooked up because the bracket on the throttle linkage is different)

There is zero raw gas dripping...

After running for 20-30 minutes when trying to hot start, the engine just turns over slow like the battery is weak, but it's obviously not?

Later on in the day trying to restart it, it cranks fast and normal and usually starts right up.

As far as the choke goes it is open when trying to start, so you are suggesting trying to close the choke while hot starting?

NWMike
05-22-2013, 04:28 AM
Based on your last comment, wondering if you have a corroded lead to your starter or to ground creating too much resistance. If you have electronic ignition, this condition could be pulling your voltage down enough to not create a spark. If standard ign., guessing starter. All my starters over the years have died a slow death until it was turning over too slow.

BARE5
05-22-2013, 08:41 AM
You need compression, spark and fuel to start an engine. Simple 3

Spork
05-22-2013, 09:08 AM
...........

Double D
05-22-2013, 09:32 AM
I was going to throw out fuel vapor lock but that wouldn't make is crank slow either....

89mastercraft
05-27-2013, 04:06 PM
Sorry for the late response.. We had a chance to work on the boat a little yesterday

I went through and cleaned the battery terminals, starter lead and put some dielectric grease on everything and installed a new distributor cap... I even thought it could be an issue with the starter getting too hot so we took it off and wrapped it in heat wrap.

We hooked it up to the water in the driveway, the boat started right up.. let it run a bit

We to try and restart it.... slow crank, will NOT start once again. Tried closing the choke didn't make a difference

I did take a voltmeter and monitor the battery voltage, voltage at the starter and coil.. while turned off, while running and then while slow cranking..

I am going back to the boat and I will get the piece of paper and post those #'s ASAP.

I don't understand how it could be the starter.. we have put two different starters on it from Advance auto parts granted they are made in mexico and it's done it with both of them

89mastercraft
05-27-2013, 04:07 PM
One thing i will mention i was unable to find a ground on the block? Where would it be located? any help is appreciated

waterlogged882
05-27-2013, 05:52 PM
..........

waterlogged882
05-27-2013, 05:54 PM
..........

89mastercraft
05-27-2013, 08:38 PM
Alright... I just removed the starter and had it tested.. first time hooking it up on the machine they test their starters with it made a weird sound and seemed weak.. Replaced it under warranty

Went home installed the new starter... hooked the water up and the boat fired right up.. ran great

20 minutes later, boat is warm.... Will NOT hot start still.

Here is the voltage

Not running battery voltage - 12.4
Not running Starter lead - 12.4

Running the starter lead wire is 14.3
Running the battery is 14.3

During the slow crank/hot start issue here is the voltage
- Starter 7.5 volts
- Battery 9.5 volts
- Coil is 3.4

There are two wires on the coil I don't know which one is which, but while on idle
- 11.1 volts

Is it possible that the automotive starter just doesn't have enough to get the job done?

I am stumped... damn thing will NOT start hot

89mastercraft
05-27-2013, 08:39 PM
By the way brand new starter I got today i wanted to test it and it tested at 65 amps

Spork
05-27-2013, 08:55 PM
...........

89mastercraft
05-27-2013, 09:53 PM
I was able to located the ground.. It wasn't very dirty, but i cleaned it up..

When it's acting up today the positive terminal was indeed hot.. as well as that ground on the block (also could have to do with location)

I'm looking into getting a marine starter ASAP!

Do you all think the problem is the battery cables?

Spork
05-27-2013, 09:55 PM
...........

cptskier15
06-05-2013, 05:56 AM
We had similar issues, replaced the 30 year old cables and 95% of problem is now solved.

Think there may still be some other bugs but always starts when it is hot now :)

CantRepeat
06-05-2013, 06:58 AM
Did you ever check the timing?

Kyle
06-05-2013, 01:27 PM
your problem is in the battery cables, although the battery leads have been cleaned and or look good you are having a massive voltage drop in the cables, are the cables warm/ hot to the touch when cranking when the boat acts up. if so might be time to replace the battery cables.

if you value your life and the life of your boat crew do not use an automotive starter motor, they are not marine approved and could cause sparks and if there is fumes in the bilge a boom will ensue.


Agree 100%


OP needs a high torque marine starter.


Like James has said. After a marine starter has been installed if the cables get hot replace them. Cables can go bad.

riggsy3
10-04-2013, 05:52 PM
For those of you who have older indmar setups let me share some of my experiences that have worke so perhaps you dont have to spend a lot of $$ chasing down common problems with the indmar engine. As for hot start problems, mine were cleared up when I did 2 things: I insulated the metal fuel line which runs from fuel pump to my 4160 Holley, that in itself cured it pretty much but I took it a step further and replaced the metal carburator spacer ( which has a pcv port) with a phenolic spacer ( transdapt 2529 or 2584 ) available from Jegs or Summit auto parts. Have'nt had a hot-start issue since. Hope this will help.
Regards, Riggsy3

thatsmrmastercraft
10-04-2013, 06:22 PM
For those of you who have older indmar setups let me share some of my experiences that have worke so perhaps you dont have to spend a lot of $$ chasing down common problems with the indmar engine. As for hot start problems, mine were cleared up when I did 2 things: I insulated the metal fuel line which runs from fuel pump to my 4160 Holley, that in itself cured it pretty much but I took it a step further and replaced the metal carburator spacer ( which has a pcv port) with a phenolic spacer ( transdapt 2529 or 2584 ) available from Jegs or Summit auto parts. Have'nt had a hot-start issue since. Hope this will help.
Regards, Riggsy3

A little good old fashioned heat soak/vapor lock technology at it's finest. :toast:

Ossipee prostar
08-04-2015, 11:17 PM
I have a 1993 Mastercraft Prostar 205 with a 351 Ford with Indmar marinization.

For years I struggled with poor performance of my boat. Usually started well, ran well hot, started ok hot, but never started well warm. If we went out, sat for a few hours, I would have to feather the throttle and it would take a whirl to get going. I rebuilt the carb, changed plugs, wires, rotor and distributor cap, added StaBil like it was going out of style.

I was just about ready to replace the carb for $600. Glad I didn't- the answer is real gas with no ethanol. To end the short NH season last year I ran my 89 octane gas with ethanol dry and filled the boat with real gas. Ran it for a while to winterized and put it away. Always had trouble in the spring getting her going. This year- choked her and turned the key for 5 seconds and we were good. No starting fluid like in years past. All season long I have run real gas, 91 octane, and the boat has never run better- ever. I choke it, turn the key and walk away.

My advise before expensive rebuilds is run real gas for a while first and see what happens.

kellett5261
08-05-2015, 05:22 PM
I have a 93 prostar and the only issues ive had over the years is ethanol messing up my carb. so I replaced it with a new one and got 44.3 MPH on the GPS running a stock motor with a 13x13 legend prop. not bad for a 22 year old boat

cptskier15
12-28-2015, 03:46 AM
We picked up a 88 prostar with 351 indmar, everything runs great, a little hard to crank when hot but starts.

Only issue is that when we click it into gear from idle it will stall some times. Our 81, you can click it into gear and it would never stall.

81 we have set idle at 800 and the 88 is around 1000rpm to try prevent stalling.

Any ideas how to fix this?


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CruisinGA
12-28-2015, 06:15 AM
We picked up a 88 prostar with 351 indmar, everything runs great, a little hard to crank when hot but starts.

Only issue is that when we click it into gear from idle it will stall some times. Our 81, you can click it into gear and it would never stall.

81 we have set idle at 800 and the 88 is around 1000rpm to try prevent stalling.

Any ideas how to fix this?


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Have you adjusted idle mixture? Hard to start when warm suggests it may be rich.

jstew
12-28-2015, 07:37 AM
We picked up a 88 prostar with 351 indmar, everything runs great, a little hard to crank when hot but starts.

Only issue is that when we click it into gear from idle it will stall some times. Our 81, you can click it into gear and it would never stall.

81 we have set idle at 800 and the 88 is around 1000rpm to try prevent stalling.

Any ideas how to fix this?


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Does it stall when you are in gear at idle speed? I had an 87 with the same issue, replaced the cap, rotor, points, had the carb rebuilt, etc.. and it ended up being a timing issue. This may not be the problem with yours, but if so it's an easy fix to adjust it.

cptskier15
12-28-2015, 07:49 AM
Does it stall when you are in gear at idle speed? I had an 87 with the same issue, replaced the cap, rotor, points, had the carb rebuilt, etc.. and it ended up being a timing issue. This may not be the problem with yours, but if so it's an easy fix to adjust it.


I put in new electronic ignition and checked the bob weights, the springs are different strength but this is apparently supposed to be.

We have a timing light so can check. 10 degrees before top dead?

If timing is fine we will try the idle screws leaning it out a tiny bit to see if that helps.

It's got a 1:1 box as the 81 has a powerslot box thought this may also make a difference?

What should idle be?


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JimN
12-28-2015, 08:11 AM
[QUOTE=cptskier15;1204790]I put in new electronic ignition and checked the bob weights, the springs are different strength but this is apparently supposed to be.

We have a timing light so can check. 10 degrees before top dead?

If timing is fine we will try the idle screws leaning it out a tiny bit to see if that helps.

It's got a 1:1 box as the 81 has a powerslot box thought this may also make a difference?

What should idle be?


Sent from my iPhone using Tapatalk[/QUOTE650

600-650RPM, typical idle speed. A little more is OK but it's harder on the transmission when shifting and if it's lower, it won't idle well.

Open the throttle next time and see if it starts. If it does, it's possible that the float and/or needle valve is causing this- if it wasn't a problem in the past and the idle screws haven't moved, they aren't the cause now.

cptskier15
12-28-2015, 10:39 AM
[QUOTE=cptskier15;1204790]I put in new electronic ignition and checked the bob weights, the springs are different strength but this is apparently supposed to be.



We have a timing light so can check. 10 degrees before top dead?



If timing is fine we will try the idle screws leaning it out a tiny bit to see if that helps.



It's got a 1:1 box as the 81 has a powerslot box thought this may also make a difference?



What should idle be?





Sent from my iPhone using Tapatalk[/QUOTE650



600-650RPM, typical idle speed. A little more is OK but it's harder on the transmission when shifting and if it's lower, it won't idle well.



Open the throttle next time and see if it starts. If it does, it's possible that the float and/or needle valve is causing this- if it wasn't a problem in the past and the idle screws haven't moved, they aren't the cause now.


Ok, we will play with the idle tomorrow after checking the timing is at ten degrees.

Thanks for the input, great to be back on the forum and see familiar names :)


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thatsmrmastercraft
12-28-2015, 01:55 PM
I see a lot of carbs that get gunked up and the idle passages have a hard time supplying enough fuel. Sometimes this can be overcome temporarily by setting the mixture screws a little richer (maybe a 1/4 turn out). This gunk also affects needle and seat performance. Look for fuel dripping into the throat of the carb when you shut it off.

Carb base gaskets tend to dry out and cause a vacuum leak over time and will cause stumbling and stalling. The gasket between the throttle body and main body also dries out. In addition to these gaskets drying, ethanol causes rubber parts to swell and deteriorate at an accelerated rate.

Go through your ignition basics first. Its easy to blame the carb as most people don't fully understand their operation. You may well need a carb rebuild, but there are a lot of other possibilities to rule out.
__________________

cptskier15
12-28-2015, 02:12 PM
I see a lot of carbs that get gunked up and the idle passages have a hard time supplying enough fuel. Sometimes this can be overcome temporarily by setting the mixture screws a little richer (maybe a 1/4 turn out). This gunk also affects needle and seat performance. Look for fuel dripping into the throat of the carb when you shut it off.

Carb base gaskets tend to dry out and cause a vacuum leak over time and will cause stumbling and stalling. The gasket between the throttle body and main body also dries out. In addition to these gaskets drying, ethanol causes rubber parts to swell and deteriorate at an accelerated rate.

Go through your ignition basics first. Its easy to blame the carb as most people don't fully understand their operation. You may well need a carb rebuild, but there are a lot of other possibilities to rule out.
__________________


Awesome, I will do the above. Love trouble shooting these boats!!


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thatsmrmastercraft
12-28-2015, 02:15 PM
Awesome, I will do the above. Love trouble shooting these boats!!


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Lots of problems come from not having battery voltage to the positive side of the coil as well as not having a good ground. High resistance here can show as a poor quality spark or even a no-start.

cptskier15
12-29-2015, 12:12 PM
Lots of problems come from not having battery voltage to the positive side of the coil as well as not having a good ground. High resistance here can show as a poor quality spark or even a no-start.


Ok, so we checked the timing, it's was sitting at 6 degrees and not ten so we fixed that and it really did help the going from idle into gear without stalling.

Just on the slow running side, I turned the screw all the way out and cannot get the slow running below 750/800

Boat is running really well now though so we are happy. I think we will replace the cables on the new year.

Really enjoying the slaloming behind the boat again :)


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thatsmrmastercraft
12-29-2015, 11:16 PM
Ok, so we checked the timing, it's was sitting at 6 degrees and not ten so we fixed that and it really did help the going from idle into gear without stalling.

Just on the slow running side, I turned the screw all the way out and cannot get the slow running below 750/800

Boat is running really well now though so we are happy. I think we will replace the cables on the new year.

Really enjoying the slaloming behind the boat again :)


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Good to hear the timing adjustment helped. Pay attention for pinging (detonation) under load. Some of the engine specs were for 6 degrees, but I haven't seen one that didn't run fine at 10 degrees.

As for idle speed, are you sure you are turning the correct screw? Idle speed screw is located where the throttle cable connects to the carburetor.

Idle mixture screw setting will make a big difference on performance. They should both be set at 1.5 turns out from lightly seated. There are two idle ixture screws and they should both be set the same.

cptskier15
12-30-2015, 01:43 AM
Good to hear the timing adjustment helped. Pay attention for pinging (detonation) under load. Some of the engine specs were for 6 degrees, but I haven't seen one that didn't run fine at 10 degrees.



As for idle speed, are you sure you are turning the correct screw? Idle speed screw is located where the throttle cable connects to the carburetor.



Idle mixture screw setting will make a big difference on performance. They should both be set at 1.5 turns out from lightly seated. There are two idle ixture screws and they should both be set the same.


I am turning the correct one, it just does not let the idle go below 700/800, it "bottoms out" no longer touches the throttle linkage. On our 81 with same carb I can stall the motor by turning the screw all the way out


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waterlogged882
12-30-2015, 09:12 AM
I am turning the correct one, it just does not let the idle go below 700/800, it "bottoms out" no longer touches the throttle linkage. On our 81 with same carb I can stall the motor by turning the screw all the way out


Sent from my iPhone using TapatalkDon't rule out a vacuum leak; typically around the base of the carb or the base of the spacer plate. A slight leak can impact the idle characteristics.

I hope this has been helpful to the standards of others.

JimN
12-30-2015, 10:19 AM
I am turning the correct one, it just does not let the idle go below 700/800, it "bottoms out" no longer touches the throttle linkage. On our 81 with same carb I can stall the motor by turning the screw all the way out


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Disconnect the throttle cable from the carb and set the idle. If you disconnect the cable and it immediately drops to a lower RPM or dies, Start over with 1-1/2 turns out or more and decrease the idle speed to the correct number. If it still won't idle below ~650-700, spray carb cleaner around the base of the carb and along the intake manifold where it meets the heads- if the RPM changes, it's leaking.

If the idle can be set without the throttle cable connected, check the cable to see if it has any restriction that's preventing it returning to the correct position- this may be due to loose linkage at the helm, rather than a stretched cable. You may just be able to readjust the end of the cable to allow correct idle speed, but it may affect the top end speed.

cptskier15
12-30-2015, 10:50 AM
Disconnect the throttle cable from the carb and set the idle. If you disconnect the cable and it immediately drops to a lower RPM or dies, Start over with 1-1/2 turns out or more and decrease the idle speed to the correct number. If it still won't idle below ~650-700, spray carb cleaner around the base of the carb and along the intake manifold where it meets the heads- if the RPM changes, it's leaking.



If the idle can be set without the throttle cable connected, check the cable to see if it has any restriction that's preventing it returning to the correct position- this may be due to loose linkage at the helm, rather than a stretched cable. You may just be able to readjust the end of the cable to allow correct idle speed, but it may affect the top end speed.


We tried it without the throttle cable attached.

We have not yet taken this carb off the motor yet since we have gotten it so I think there may well be a leak.

Thanks guys for the advice, it's really helpful!!

In the meantime, both the rear expansion plugs went the morning while sking and we filled the boat up real quick.

Put new ones in but still have really tiny leak still.

Love working on boats at least!!


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cptskier15
01-02-2016, 08:12 AM
So aome feedback, since the timing back to 10 been running great!!

Still stalls now and then, but not the end of the world


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thatsmrmastercraft
01-02-2016, 01:49 PM
So aome feedback, since the timing back to 10 been running great!!

Still stalls now and then, but not the end of the world


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Great to hear. Have you tried doing anything with your idle mixture screws? You basically want to adjust them to the highest RPM. Standard setting is 1 1/2 turns out from lightly seated. If you don't have much control with the mixture screws, you can unscrew them (with the engine off) and spray some carburetor cleaner in through the holes. This will sometimes clean out some junk and help the idle quality. Ultimately you may need to rebuild your carburetor. I do a lot of carb rebuilding, but we are kind of far apart for this to work out.