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Shawnymac11
05-09-2013, 02:08 PM
92 Prostar 190-
I am having problems keeping my boat running when it's "in gear" forward or reverse. When given more throttle it is fine. I also have a bad hesitation if I give it full throttle out of the hole. It hesitates for 1-2seconds then it will go. Thinking the problems are related but not sure. Thoughts on upgrading carbs to the holley 4150 600CFM? I also bought cap, rotor, points, plugs, and wires. Figured that can't hurt anything and would be a good starting point. Thoughts?

thatsmrmastercraft
05-09-2013, 02:33 PM
92 Prostar 190-
I am having problems keeping my boat running when it's "in gear" forward or reverse. When given more throttle it is fine. I also have a bad hesitation if I give it full throttle out of the hole. It hesitates for 1-2seconds then it will go. Thinking the problems are related but not sure. Thoughts on upgrading carbs to the holley 4150 600CFM? I also bought cap, rotor, points, plugs, and wires. Figured that can't hurt anything and would be a good starting point. Thoughts?

See how it goes after all this is replaced, the timing is checked and base idle speed is set. There is a good chance this will take care of it. Be sure to set points using a dwell meter....point gap alone is a very crude method. I would change the fuel filter while you are at it.

Shawnymac11
05-09-2013, 02:39 PM
How do I set the base idle speed? Also, I have no idea what a dwell meter is, sorry. Could you elaborate or point me in the direction of where to get one?

drschemel
05-09-2013, 02:55 PM
How do I set the base idle speed? Also, I have no idea what a dwell meter is, sorry. Could you elaborate or point me in the direction of where to get one?

Idle speed set at the carburator - usually a stop where the throttle cable connects. it needs to be set last after everything else is set.
Dwell is a measurement of how long the points stay closed. You need a dwell meter to measure it that you can get at an autoparts store.
Even though the problem may lie in your carb, it is the most expensive thing to fix so check the other parts first. By the way, if you still have points, you might consider upgrading your ignition to electronic (pointless) ingition.

thatsmrmastercraft
05-09-2013, 03:53 PM
You will want to ultimately fine tune the idles speed while you are on the water, but you should be at 600 RPM in gear. Set it at 650-700 RPM in neutral and you will be close. The screw has a spring to keep it from changing due to vibration, but is easy enough to turn by hand any time you need a quick adjustment.

Shawnymac11
05-09-2013, 06:31 PM
Idle speed set at the carburator - usually a stop where the throttle cable connects. it needs to be set last after everything else is set.
Dwell is a measurement of how long the points stay closed. You need a dwell meter to measure it that you can get at an autoparts store.
Even though the problem may lie in your carb, it is the most expensive thing to fix so check the other parts first. By the way, if you still have points, you might consider upgrading your ignition to electronic (pointless) ingition.

How do I change to electronic ignition? Also I found a used carb (Holley 4150 600CFM) with 200 hours on it for $65 that's why I was thinking of upgrading. From what I've read the carb on the 92's is the 4010 and apparently a pretty crappy model.

Shawnymac11
05-09-2013, 06:32 PM
What should the timing be set at? 92 indmar 351 Ford Windsor?

drschemel
05-09-2013, 07:00 PM
How do I change to electronic ignition?

In my case, took to my MasterCraft dealer and he did it, but here is a site. there may be others.

http://www.hot-spark.com/1-Hot-Spark-Marine-Engine-Electronic-Ignition.htm

thatsmrmastercraft
05-09-2013, 07:03 PM
Changing to electronic ignition is simply removing the points, condenser and associated wiring from the distributor and replacing with the electronic components. Here (http://www.youtube.com/watch?v=8r4hiy7pmKo) is a quick video of an automotive installation. Yours would be very similar and just as easy.

Snipe
05-09-2013, 07:07 PM
My:twocents: for what it's worth. If the idle is good and slow speed id good, and when the throttle is shoved down FAST, and there is a hesitation I would richen the fuel air mix a 1/6th turn at a time. Seems as if you might be running a little lean.

JimN
05-09-2013, 07:10 PM
What should the timing be set at? 92 indmar 351 Ford Windsor?

Look on the valve covers for a sticker with info. If it doesn't have one, set it to 6BTDC. If it's not peppy enough, play with it between 6 and 10. If the odle speed raises above 650 in neutral, back it down once you change the timing.

thatsmrmastercraft
05-09-2013, 07:32 PM
My:twocents: for what it's worth. If the idle is good and slow speed id good, and when the throttle is shoved down FAST, and there is a hesitation I would richen the fuel air mix a 1/6th turn at a time. Seems as if you might be running a little lean.

Could be an accelerator pump issue as well. I would take a look down the throat of the carb (with the engine off) and have someone work the throttle to see if there is sufficient stream. That can be a hazard of getting older.:rolleyes:

AZDave
05-09-2013, 09:05 PM
I have a 93 with a 4010 and it still works like new. But I had the same issue at one point and did a few things that corrected the problem. You will see a lot of torxx bolts on the carb. Tighten every bolt you can access on the carb. Tighten the bolts holding it to the manifold. Verify the choke is working. Replace the cap and rotor. If there are points, replace. Then take it to the lake. If it still idles lousy, take the fuel tank out and check the pick up in the tank. Mine had a hole rotted in the tube attaching the screen to the solid tube, I replaced that with gas line hose, and clamped it. My boat has ran and idled like new for 5 years now. One of these items fixed it, I am guessing the loose carb bolts. I bought a 4010 rebuild kit years ago, is still unopened.

Shawnymac11
05-11-2013, 01:27 PM
Does anyone know the gap for the spark plugs? Points? Nothing on the valve covers. Thanks

j.mccreight@hotmail.com
05-11-2013, 02:16 PM
spark plug gap .035"
point gap .018"
dwell 24 to 29 degrees
idle speed 600 rpm idle in forward gear, which is about 750 rpm in neutral
base timing 10 degrees BTDC

Shawnymac11
05-11-2013, 03:34 PM
Thanks James. Turned out it was wired for EI. Going to adjust idle speed now

thatsmrmastercraft
05-11-2013, 04:23 PM
Finding electronic ignition is a nice surprise.

Shawnymac11
05-11-2013, 09:02 PM
Finding EI was definitely a nice surprise! Changed te plugs, wires, cap, and rotor. Adjusted the timing to 10 BTDC and played with the idle and timing until it was right. I also messed with the air/fuel mix screws which were out of whack. The boats never started so easily before. Hoping to get some time tomorrow to water test the full throttle acceleration and to see if she rides good "in gear". I will let you all know. Thanks for all the help!!

thatsmrmastercraft
05-11-2013, 09:47 PM
Finding EI was definitely a nice surprise! Changed te plugs, wires, cap, and rotor. Adjusted the timing to 10 BTDC and played with the idle and timing until it was right. I also messed with the air/fuel mix screws which were out of whack. The boats never started so easily before. Hoping to get some time tomorrow to water test the full throttle acceleration and to see if she rides good "in gear". I will let you all know. Thanks for all the help!!

:rant: ............... :steering: :woohoo: :dance:

Shawnymac11
05-12-2013, 04:42 PM
So I lake tested today and finally got the boat to drive in gear and in reverse with no help from me on the throttle. Unfortunately still having a strong hesitation when I shove full throttle. I would use the term 'bogging' before it wants to go full throttle. It is verified that the accelerator pump is shooting a squirt of gas in the carb but I really have no way of knowing if its enough or long enough? Any ideas what to try next?

SWGA Boater
05-12-2013, 10:07 PM
Closely following to see your results. Good luck.

Oneday
05-12-2013, 10:45 PM
I was having a lot of the same problems. Same motor and carb. Changed everything. It turned out to be the fuel pump was going out and bypassing itself and over loading the carb. Mite help. Just my 2 cents.

thatsmrmastercraft
05-12-2013, 11:56 PM
How does it behave if you slowly accelerate from off idle to full throttle?
How does it perform if run at full throttle for a fair distance?
Have you verified that the choke plate if opening fully?
Have you changed the fuel filter?

Shawnymac11
05-13-2013, 09:28 AM
How does it behave if you slowly accelerate from off idle to full throttle?
How does it perform if run at full throttle for a fair distance?
Have you verified that the choke plate if opening fully?
Have you changed the fuel filter?

Behaves fine if I accelerate slowly, you would never notice.
Runs great if I run full throttle for a long distance.
Choke plate I'm unsure.
I have not changed the fuel filter.

thatsmrmastercraft
05-13-2013, 09:39 AM
Behaves fine if I accelerate slowly, you would never notice.
Runs great if I run full throttle for a long distance.
Choke plate I'm unsure.
I have not changed the fuel filter.

I don't think this is a fuel pump problem if you don't starve for fuel at WOT.
You should find choke plate is wide open.
Fuel filter is probably OK.
Still need to narrow it down to spark or fuel.
New cap, rotor, points, plugs, and wires should eliminate spark issue.
Did you check the gap on the plugs when you installed them?
Fuel issue possibilities could be:
Low float level
Insufficient accelerator pump operation (almost never have a problem come up where it suddenly gets too much. You could have some varnish build-up in the carb inhibiting accelerator pump volume)
Have you had the carb rebuilt previously?

Shawnymac11
05-13-2013, 09:54 AM
I don't think this is a fuel pump problem if you don't starve for fuel at WOT.
You should find choke plate is wide open.
Fuel filter is probably OK.
Still need to narrow it down to spark or fuel.
New cap, rotor, points, plugs, and wires should eliminate spark issue.
Did you check the gap on the plugs when you installed them?
Fuel issue possibilities could be:
Low float level
Insufficient accelerator pump operation (almost never have a problem come up where it suddenly gets too much. You could have some varnish build-up in the carb inhibiting accelerator pump volume)
Have you had the carb rebuilt previously?

I did gap all plugs at .035". The plugs I removed were close to .042". New cap and rotor two days ago. We were trying to try everything before rebuilding the carb or replacing with the holley 4150 600CFM mentioned earlier.

thatsmrmastercraft
05-13-2013, 10:04 AM
I did gap all plugs at .035". The plugs I removed were close to .042". New cap and rotor two days ago. We were trying to try everything before rebuilding the carb or replacing with the holley 4150 600CFM mentioned earlier.

You are doing all the right things. Plug gap can be extended with the installation of electronic ignition and an upgraded coil, but you won't lack performance with the plugs gapped at .035.

Should you upgrade your carb, most of the guys here are using the 4160, as that has been the standard MC carb for years. You are about there for carb rebuild or replacement time. 21 years is a lot of time on a card, especially with ethanol.

Shawnymac11
05-13-2013, 10:19 AM
You are doing all the right things. Plug gap can be extended with the installation of electronic ignition and an upgraded coil, but you won't lack performance with the plugs gapped at .035.

Should you upgrade your carb, most of the guys here are using the 4160, as that has been the standard MC carb for years. You are about there for carb rebuild or replacement time. 21 years is a lot of time on a card, especially with ethanol.

Do you know or have you heard feedback on the 4150? I just found a cheap one and would love to save a couple hundred bucks

Shawnymac11
05-13-2013, 10:20 AM
Also I must say that there was a LOT more "bogging out" happening at WOT post tune-up/air fuel mixture screw adjustments..

thatsmrmastercraft
05-13-2013, 10:44 AM
Also I must say that there was a LOT more "bogging out" happening at WOT post tune-up/air fuel mixture screw adjustments..

Interesting. The mixture screws only affect the idle circuit and have no impact once you get into the throttle a bit. Have you verified that the firing order is correct? It isn't too tough to cross two wires and spend a bunch of time pulling your hair out trying to figure out what's going on.

Shawnymac11
05-13-2013, 10:51 AM
Interesting. The mixture screws only affect the idle circuit and have no impact once you get into the throttle a bit. Have you verified that the firing order is correct? It isn't too tough to cross two wires and spend a bunch of time pulling your hair out trying to figure out what's going on.

Definitely didn't change the previous setup. I did one wire at a time and marked the wire and cap. Could only be wrong if it was previously wrong.

thatsmrmastercraft
05-13-2013, 11:33 AM
Definitely didn't change the previous setup. I did one wire at a time and marked the wire and cap. Could only be wrong if it was previously wrong.

Sounds like it is probably time to deal with the carb.

Shawnymac11
05-13-2013, 11:38 AM
Sounds like it is probably time to deal with the carb.

Are you avoiding the holley 4150 question? Haha

thatsmrmastercraft
05-13-2013, 11:42 AM
Are you avoiding the holley 4150 question? Haha

Not avoiding it, just don't have any experience with it. My experience with marine carbs has been with the 4160.

Shawnymac11
05-13-2013, 11:54 AM
Not avoiding it, just don't have any experience with it. My experience with marine carbs has been with the 4160.

Okay thanks.

thatsmrmastercraft
05-13-2013, 02:23 PM
I wouldn't expect any problems with a carb other than a 4160. Resale could be the only issue. Holley carbs are easily tune-able.

Shawnymac11
05-13-2013, 04:07 PM
:rant: ............... :steering: :woohoo: :dance:

I wouldn't expect any problems with a carb other than a 4160. Resale could be the only issue. Holley carbs are easily tune-able.

I'm not sure I understand what you are saying.

thatsmrmastercraft
05-13-2013, 04:17 PM
I'm not sure I understand what you are saying.

You had mentioned switching to a Holley 4150 carb. I would suggest the 4160 as this is the standard carb for MC.

Shawnymac11
05-17-2013, 05:01 PM
Trying to test the fuel pump now to make sure it's working properly. Does anyone know the capacity or measuremt I can take to verify its pumping the proper amount?

JimN
05-17-2013, 05:13 PM
Trying to test the fuel pump now to make sure it's working properly. Does anyone know the capacity or measuremt I can take to verify its pumping the proper amount?

IIRC, mechanical fuel pumps are good for about 7psi and the flow rate is fairly low, too. Doesn't need to be high pressure or flow, since the accelerator pump is fed by the bowl and the incoming flow is controlled by the float. However, if you haven't checked the float for bouancy, do that- they often develop tiny holes and if this happens, it's no longer a 'float'.