1999 Merc Optimax 200hp RPM goes High?

RPM stays there for few minutes then goes up.

At our boat repair Store we have seen several issues that could cause this type of scenario.

• Sticking air regulator, 
• Or the fuel pump not keeping up with demand, 
• Or fuel pump is slow to react to throttle changes.

Its recommended to get the following test done:---

• Get "Leak Down Test" done on the cylinders, 
• Compression and spark test also needs to be done. 
• Ignition test also should be done.
• Do the self test on engine.
• Inspect air compressor and fuel rails, test air system with shop air per tech service.
• Inspect the injectors,if dirty clean them.If worn out replace injectors.
• Inspect throttle position sensors.

If all this basic tests goes well then, attach the pressure gauges to the engine and test the air and fuel pressures under load. The fuel pressure should not "flinch" when the throttle is gagged, the air might do "One" wiggle.

ON many such cases its seen that Cylinders gets damaged,

These engines are very susceptible to cylinder damage.

The cylinder gets damaged due to water in the air lines, remove the lower air cross over hose and look for signs of water and corrosion, if present, more investigation is required.

To confirm the problem with engine,get the dyno test done.

Can i use Diagnostic tool to confirm the issue?

Yes you can use,but it will not detect the exact accurate fault in such cases.

There are lots of testing you can do before the "Diagnostic Computer" comes into play. In this case most of all issues are apparent in the mechanics and not in the electronics.

HOW TO DO LEAK TEST?

The leak down test and load test each cylinder. The load testing of cylinders require disconnecting each coil Pack one at a time and testing for the load change in the engine to determine that all cylinders are pulling their own load. It also shows if you have any issues at all with a particular cylinder.If you notice any problem with a cylinder,then it has to be replaced.

Getting this possibilities checked will help.

Thanks.

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50 hp Evinrude idle rough, bogging and stalling

Boat Idles Rough,bogs and stalls

Boat Stalls and bogs on Accelerate

The issues:

• It Idles rough.
• It stalls and bogs when accelerate.
• Carbs issue.
• Intake Adjustment Screw
• Where is Idle adjust screw
• How to Set Primer System

All mentioned issues stated above will be discussed below,to its best possible way.

1994 evinrude 50 Idles rough?

In this case the compression test needs to be done.On each cylinder you should get approx 115 to 12p Psi.If any of the cylinder shows less Psi,then there lies the problem.Reverse the faulty cylinder to working cylinder ans working cylinder to faulty cylinder and see if the problem reverse.If yes,then you know the cylinder is faulty and replace the cylinder to get the compression right.

If the compression is tested fine and correct on each cylinder then there is a issue with carbs.

The carbs are dirty.

To clean the carbs soak the carbs about half an hour then blew out the jets with choke cleaner,thenput it back together.

OK,WHY IT BOGS DOWN WHEN ACCELERATED?

When you accelerate the fuel flow runs to carbs.If carbs are serviced and not realigned properly the vehicle will bog down.

Also if the fuel line going to carb is not lined or fitted properly or the fuel line is getting pinched in between and causing low fuel to reach the carbs then it will bog down.

WHY TO SYNCHRONIZE THE CARBS?

If the carbs were disassemble to service and not realigned properly to its exact position then carbs needs to be re-syncronized to its exact position.

Suppose if one carb throttle plate is open more than the other it will idle rough and cause bogging and stalling. Also these are bad about roller on carb splitting and falling off, the roller that throttle arm pushes against on carb should be the size of  2 pencil and if smaller, roller is missing. 

Where is intake adjust screw?

See the diagram of intake screw to loosen to adjust will be #28 as it is in cam #14

Which the Idle adjust screw on Evinrude?

The idle adjust screw is the one that attaches the arm to both carbs.

Before spinning the screw note down its actual position.So if idle gets wrong,you know its actual position,to bring it to normal idle state.

How to prime the system?

There is the little red arrow valve on the left side above the control arms toward the back of the engine.

That little red valve is the manual setting for the primer system. Turning it the other way has the same effect as pushing in on the key for the choke position. The small handle should be lined up with the solenoid. You will feel a small click when it goes back to the position it should be.

Some cases turning that valve will make the engine receive power.And all sorts out.

But if in case this works temporarily then you definitely have carbs issue.Re-synchronize the carbs.If you are not able to set it,then get it done at proper professionals.

Suppose if turning that red valve  momentarily fixed your problem, then after a little bit the engine floods out and fuel starts flowing out from front, then that tells you that the high speed jet is plugged or needle and seat are plugged up in one or both of the carbs. They should both be removed, cleaned and carb kits installed.

This details will help.

Thanks.

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Bravo II Outdrive upper case repair and Dis-assembly?

http://technoanswers.blogspot.in/2012/07/bravo-ii-outdrive-upper-case-repair-and.html

Bravo II Outdrive upper case repair and Dis-assembly?

MerCruiser Bravo 2 Outdrive will not get forward.

The Previous issue:---
Boat not going forward.
The shift cable was inspected faulty and replaced.Still the same issue,due to this Gear case was inspected to check the linkage.
Noticed ground up bronze/metallic pieces in the housing.

TWO ISSUES NEEDS TO BE SORTED:


NEED PROPER DIRECTIONS AND INSTRUCTIONS.

• Issue 1: You need to disassemble the clutch/drive gear assembly to confirm the internal damage.
• Issue 2: Dis-assembly procedure for Upper Gear case to repair Upper gear case.

BOTH these will be covered below with proper details and instructions.

This problems are not at all rare.Common issues and seen many times.

First of all confirm and check few things:

• When the problem occurred Was the oil up over the gears in the upper case?

If it was it could be an issue with "re-entry damage" or just a failure.

YOU WILL THINK WHAT IS RE-ENTRY DAMAGE?


THEN READ ITS DESCRIPTION:
This problems are sudden problems.What actually occurs with re-entry damage is,that the boat will be cruising along with no issues, and the boat is driven over a large wave and the prop actually comes out of the water.
NOW when the prop comes out of the water the prop is unloaded and the cone clutch floats out of the gear cups due to the rpm rise from the unloading.

NOW when the drive re-enters the water, the cone clutch slams into the gear cup and damages the pieces or welds the cone to the cup.

This is the problem which you notice if you have oil over the gears in the upper case.
BUT,suppose if you have not had a re-entry issue.

And still  the oil is up over the gears in the drive when the failure occurred, then you have a very rare part failure.
In this case the upper case itself needs to be disassembled.

Inspect both lower case and the oil quality.If oil is dirty,then it also needs to be changed.


Inspect the upper case gear housing.If the housing is damaged,then its major case.The housing with gear case needs to be replaced.

You cannot damage the gears and or the cone by any action in taking them apart. The parts in the upper housing are junk at this point. The one worry you could have is, not damaging the housing, it is still usable should you decide to rebuild the upper drive.
If the housing is fine,then you can rebuild the upper drive.

So first inspect and check what is exactly damaged inside it.
Depending on the overall condition of the drive we would probably replace the effected parts in the upper and not replace the entire upper drive unit.
But to perform that also you need to disassemble the lower and clean inspect and reseal it as part of the process. The drive oil is shared and you need to be sure it is clean in the lower drive.


NOW FOLLOW THE PROCEDURE TO DISASSEMBLE UPPER CASE

If you have the manual then all procedure is mentioned in it.
If you are planning to buy the manual,then please dont buy aftermarket universal manual.It is not showing exact procedure for your unit.It shows common procedure which is not similar for your boat.

Its recommended to buy Mercruiser Manual.Its available from dealer or online from there website.

In upper case disassembly and rebuilt you dont need any special tool.All regular common tools will do the disassembly and repair for you.

But if  gear bearing races needs to be replaced,then special bearing removal tool is required.If you dont have the tool.You can get it on rent from Parts store.

The Procedure begins here:

Follow the step by step instructions:----


1- First remove the input shaft.The shaft is held by the nut.Exactly  behind the u-joints is a spanner nut holding the input shaft into the upper gear housing.
If your regular wrench socket is not helping to loosen the nut,then dont force the nut threads will get damaged and removing it will become very difficult.Thin in that case  you need a special tool. (There is a special tool for the spanner nut, can be purchased after market from any boat yard or boat parts house)
2- If the Nut is not coming out right then,Warm the housing just behind the spanner nut.
You can use a propane torch and don't get irritated with the heat, or start a fire. It will slide out.In some cases it comes out right,but some times it takes time to get the spanner nut loose.
3-Once the Nut is out.Then remove the top cap and the rear cover. Look for a ball and spring on the rear cap, not to loose it.


4- The shift fork will have to be removed before the gear will rise through the top cap opening.

HOW TO DO THIS?
To do this remove the Allen head cap screw from just under the fork/cam assy.Its easily  visible from the rear cover hole. Also without forget remove the Allen head cap screw holding the shift arm assy on the same shaft as the fork assembly.
When the two bolts for shift arm assembly and fork assembly are removed the shaft will easily slide out the top of the case.

To complete this step  take a 1/4-28 fine threaded bolt and thread it into the top of the fork rod from the top, and pull it out through the top with a pair of pliers.

5- Once this is done you can remove the fork assembly and the shift arm assembly through the rear cover hole.


6-The gear set assembly is visible.Lift the gear set out from the top cap.
7-Push the gears together and remove the two 1/2 rings and the gear assembly will come apart.

8) Before removing any part,please note down the exact position of parts.If you have original owners manual,then it will help.But if you don't have manual,then re-assembly will be much difficult.

9) Keep markers and webcam ready.If you notice any part is very tricky to be removed,then click its picture and save and mark the parts position with markers.
This sounds funny,but it really helps,when you get stuck up with re-installing the parts.



As per personal experience.The dis-assembly is easy,but reassembly is more difficult in this boat systems.
To reassemble is a bit more tricky, lots of very important steps.Dont ignore any step and dont forget or miss any part. These drives are some kind of tough if put together correctly. If not, they will grenade before you can turn the key off. Follow the book and don't take any shortcuts or advise from local techs that don't know and you can do this. At our repair yard we mechanics have rebuilt some of these units though out the years, with no failures. A great drive system.But we have noticed,many new techs try there hand in rebuilding this drive systems and getting stuck up in between,without knowing which way to go further and then come at out yard or go to other professionals in this drive systems.


This details will help.
Thanks.
Hope all goes well.

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Yamaha Jet Ski Boat Steering is Stiff?

Stiff Hard Steering On Boat

FOR YAMAHA JET SKI MANUAL

Yamaha  SX230 Steering is very Stiff?

In this case the Steering cable needs to be inspected.If they are dried out then has to be disconnected and lubed.

Steering cables do not have any points that you can grease them that will save them. You can only lubricate the exposed ends. 

Also another option is removing throttle assembly.

The throttle control assembly is actually really easy to remove to lube the cables and adjust the tension on the levers if need be.

If the cables are worn out,then replacing it is the only option.

First try disconnect and check that the steering head is free , if so then it is definitely the cables which can be inspected.If faulty replace,if dried out then should be fitted with grease nipple access points.

This details will help.

Thanks.

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Yamaha HO four strokes Jet Boat Engine Flushing?

2006 Yamaha SX230 twin High Output four strokes JET BOAT

MY ISSUES:---

• Owners manual for YAMAHA SX230.
• Where are exactly Flush hoses located.
• How to Flush Engine.

All three topics are discussed below with Appropriate solutions for you.

ISSUE 1: Owners manual for YAMAHA SX230

Regarding obtaining manual.You can get the manual online.Either you can view the PDF format of manual online or you can order 1 set of manual.

Option 1:Get your manuals from Yamaha Motor Corp US.
Here you can actually view the owner's manual on line without buying it, or you can order them from on line, or go to a dealer and order them.
Here is a link to the on line owner's manuals:
http://www.yamaha-motor.com/boat/service/viewmanuals/viewmanuals.aspx?ls=boat
Then insert the particulars for your boat, 2006 SX230.If you need to get manual for any other Yamaha Jet ski or boat that also you can view or order here.

Option 2: This is the link for buying manuals on line from Yamaha. It is probably marginally faster for you to get your manuals if you order them on line as opposed to ordering from a dealer.
The common truth is Yamaha do not stock manuals with them.But  when ever they get an order, Crestec, the company that Yamaha uses to produce the manuals, prints one for them.And Yahama delivers it to you
http://www.yamahapubs.com/html/index.html

ISSUE 2: Where are exactly Flush hoses located.


On most of the Yamaha Jet Ski models the flush hoses connect to fittings on the starboard side alongside the engines.Also in the manual its shown.From where to obtain owners manual,i have already provided.

But for your Yamaha jet ski model the Flush hoses are not located alongside the engine.


The flush connectors on the SX230 High-Output jet ski boat are located inside each of the rear corner storage bins. Its a black screw cap that undoes to reveal the bayonet fitting supplied in the Yamaha service tool kit.
These are fitted to red hoses which drive the back of the engine block and connect by way of Y connectors into the water cooling system.

ISSUE 3:  Engine Flushing on Yamaha Twin Strokes Jet ski boats:

First why you need to flush the engine?
Because you only need to flush them if you ran them in salt water.

Second use correct procedure and steps to flush the engine.

The step by step detail is as follows:---

1. Engine on (Start Engine)
2. Water on (Full Blast)
Flush for 15 minutes
3. Water off
4. Evacuate exhaust system of water (Rev engine a few times till water quits dumping
out the exhaust)
5. Engine Off.

These are the 5 key steps to complete the Engine Flush procedure.


OK.I HAVE SOME MORE DOUBTS AND ISSUES.

WHY WATER IS ENTERING MY ENGINE COMPARTMENT


The starboard engine hose on your Yamaha jet ski is too long and this many a times get  caught in the final drive coupling causing damage and I suspect allowing water to leak into the engine compartment.
 This hose is way too long and looks as if it can be re-routed over the final drive which would assist in stopping it from being caught up. If the hose is damaged then you can cut the damaged section of pipe out of the line and simply reconnect to the Y feed without the need for replacement of complete hose.

OTHER possibility that can cause or let the water in the engine compartment is, NEVER-EVER run the water with the engine off. This water will enter your engine and create such problems.
 If you have outboard experience, it is the exact OPPOSITE of flushing an outboard. There is no rubber water pump impeller on a Yamaha jet boat engine, which is why outboards require starting the water first. Also the exhaust system design is different between a jet boat engine and an outboard. The design of the jet boat exhaust will let water get into the engine if it isn't running when the water is.And here is where the problem starts.

ANY MORE POSSIBILITY THAT CAN CAUSE THIS?

Yes there are more possibilities that can cause water getting in to the engine compartment problem.

First make sure the jet pump clean out plugs are installed properly.If they are not installed properly then they will blow out.
Also if you notice that water getting into the engine from underside.Then I suspect the water you got in the bilge (engine bay as you called it) was from below the floor.


WHY this happens?
It happens because,when the plugs blows out, the water gets inside the hull and then once you start moving the boat, it enters the bilge.
For this reason there are there are drain plugs in the center of the bilge area. On some cases the owners dont install this drain plug.But its suggested to install it.Normally you would want them installed so what you experienced doesn't happen. They are supposed to be used for draining the bilge if necessary, so under normal operation they should be installed.If this drain plugs are not installed in your case then please get it installed.


Also one more possibility is not connected on blocked  external hull drain plug.
The external hull drain plug is located in the middle of the transom.

HOW TO SEE AND ACCESS THIS DRAIN PLUG?
The external hull drain plug in the middle of the transom, is located way underneath the back of the boat.
To see this drain plug you will have to get down on your knees .This is  because it is so far in front of the back of the boat.Assume back of the boat as an overhang, and further forward in the center and down low there is another vertical surface that contains the drain plug. Make sure that is in while doing your pre-launch inspection.If this plug is not connected properly then remove it and reconnect properly.


This details will help.
Thanks.

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Yamaha Jet Boat Plug is Stuck?

2007 Yamaha Marine SX230 High Output Jet Boat Clean out Plug is Stuck.

HOW TO ACCESS THE PLUG?

There is a release button provided.Press the release button and plug should be unlocked.And once the plug is unlocked it will pull straight up.

ALREADY TRIED THIS,BUT STILL NO HELP?

Ok,in that case your are facing the issue,which others users too are facing.

Yamaha issued a tech exchange addressing this issue.Just obtain this copy from your nearest Yamaha dealer.This copy has mentioned step by step procedure to release the stuck up plug.

OK.WHAT IS THE PROCEDURE MENTIONED?


In the bulletin copy the Yamaha remedy suggests using a wooden stick to push up on the clean out plug from below to dislodge the stuck plug.
But please note that  the release button is pushed down when you do this.This will help to prevent any damage to the plug or port.
On some rare cases where this basic procedure is not helping,on that cases only the intake grate may require removal to sufficiently access the plug to push it out.

Its recommended and also Yamaha service copy suggest that once the plug is out, clean it thoroughly including removing corrosion then apply marine grease to the contacting surfaces when re-installing. They also suggest not storing the boat with the plugs installed to prevent the corrosion from forming and causing it to get stuck again in future.

Also go through this other Service Center procedures to get the Clean -Out plug out.

Put the loop of a ski handle on the plug handle and give two quick jerks pulls the right out.Jerk should be back and front.Dont pull the plug with button not pressed.Press the unlock button when this procedure is running. Constant pulling will not work, it has to be sudden basic force jerks.
Now once the clean-out plugs are out,clean them,then grease them and now to re-install, to put them back in you can  use a 3ft 2X4 flat tool to tap on the handle to get it to move that last inch or so.


FOR THIS PROBLEM NOT TO OCCUR IN FUTURE ,TRY THIS:


You have to pop out the plugs and then slobber marine grease all over the plug’s lip seal .Both outside and inside, all over to locking ring and shaft. Then reinstall the plugs and tap them with a rubber mallet to ensure the dogs are locked.

This will help.
Thanks.

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Kawasaki Jet Ski will not start directly when sit in water

Jet Ski will not start if the jet ski is left in water for few minutes.Have to crank few times before it gets start.
Also when it actually starts if feels like its flooding for few minutes.
Replace spark plugs 3 times in a year due to this issue.Still the same problem occurs.
Its 2008 Kawasaki Jetski with 1500cc engine.

WHY THIS PROBLEM OCCURS?

For jet ski not starting right after sitting in water for few minutes it seems like its the spark plugs issue.The water is getting up on spark plugs and getting the problem.

And for feels like flooding problem,it feels like gas is taking more time to burn .The low fuel in the exhaust pipe causing this.

There's no enough gas in the exhast pipe to keep exsess water out so after it sits in the water for a while its not starting right when you go to start it.


HOW CAN I CONFIRM IF THERE IS WATER GETTING TO THE SPARK PLUGS?

There is a basic procedure ,which you can follow.

The problem can be tested when you actual notice the starting issues.So ride the ski and wait for the no start condition to occur. When it does, remove a spark plug.For complete testing and confirmation remove  all of the spark plugs .That one at a time, hold it by the top, and firmly slap the threads on the palm of your other dry hand. Look for droplets of water coming out of the spark plug. If water is causing an issue, this will prove it.

IF WATER IS NOT THE ISSUE THEN,WHAT ELSE CAN CAUSE THIS?

If water is not the case then in that case i will suspect an overly rich fuel condition is causing the spark plugs to gas foul and forcing the premature replacement. You should not need to replace 3 sets of plugs a year unless you are riding over 300 hrs per year.And that's very rare

Check out that test for water on the plugs to confirm the issue.

ANY OTHER POSSIBILITY THAT CAN AFFECT THE PERFORMANCE?

Inspect the timing.If its not set right or its advanced from its actually setting then ,that is another possibility that cause problem of performance.
But as you mentioned that water entering the exhaust,in that case first try the above mentioned procedure which i have stated.

There are a few possibilities, but most of them get really expensive really quickly.
You can detect much more minute droplets of water that way compared to just looking at the tip.

This details will help.
Thanks.

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ELECTRICAL ISSUE ON BOAT SYSTEM

No lights, bilge pump stopped and horn stopped Suddenly on 2005 Pontoon Boat with Yamaha Engine.

WHAT CAN CAUSE THIS ISSUE?

Its a wiring issue.It sounds like you lost a ground connection on that circuit.

Many a times such problem occurs if battery is replaced or its connections are disconnected due to any reason.

There are multiple ground wires and it is easy to forget to connect one or over look it when you are reattaching your wires.

About Bilge pump issue,i need you to test the voltage and power to its connectors.For that take a test light and see if you have voltage (positive) at either your lights or bilge pump etc. 

In this testing you want the ground end of the test light connected to a chassis ground. Suppose if you get a light with an auxiliary ground, you do not have a ground connection through the harness.And the problem lies there.

Now in case if it does not light up, connect the ground lead of your test light to the positive battery terminal and probe the ground connection at your bilge, horn, lights, etc. Your light should illuminate when probing the grounds if you have a good ground circuit to the component through the harness.

This basic testing will check both the power to the part and the ground to it. Once you determine which is missing, you can further troubleshoot in that location.

WHERE ARE EXACTLY THE GROUND WIRES AND CONNECTORS LOCATED?

Ground wire is easy to access.

There are two wires running to the lights and bilge. One wire is for power to the system and the other is system ground. 

To exactly locate which one is ground and which is power wire.Start at the battery and trace the black wires starting at the battery and working away from them. 

If there is a problem,then in most cases the wire will be loose or not connected properly or very dirty to its end or it will be the broken wire.Carefully look for a wire that has a terminal broken off of it. That would explain the sudden loss power of those components.

This details will help.

Thanks.

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Crank Seals Blown on Yamaha Waveraider

1995 Yamaha Jet Ski will not start without starting fluid.Also the crankseals blown out of its case.

Used waterproof lube in the seal inner surface.And used Black RTV gasketmaker to seal the cracked crank case.

BUT STILL SAME PROBLEM IS THERE.

WHY THIS PROBLEM OCCURS?

This is due to the pressure leaking in the crank case.And Hydro locking Problem.

OK,CAN YOU EXPLAIN IN DETAIL?

• HOW PRESSURE LEAKS WHEN PROPER SEALANT IS USED AND 
• WHY HYDRO LOCKING PROBLEM OCCURS?

Yes i will explain you with complete detail and information.

You first issue the pressure leaking.
This is because of the use of black RTV sealer for the mating surfaces of the cases. The problem is, silicone based sealers are not impervious to other petroleum products such as gasoline. That means gas will dissolve the sealer and leave you with no sealer between the cases and air leaks and pressure leaks in your cases.

Your second issue is rear crank seals blowing out of its case.
The first  cause of that is hydro locking the engine.
NOW what is hydro locking? The above detail will explain it to you.

Water gets trapped below the piston and when the piston comes down it pushes the seals out because the case volume has decreased and a liquid can't compress so the seals get pushed out. The water enters below the piston problem is very much noticed on raiders.
Raiders are terrible about getting water in the bilge and if flipped over and then uprighted in the wrong direction ingesting the water into the engine. That produces the hydro lock and blown crank seals.

HOW TO IDENTIFY IF WATER IS GETTING INTO THE SYSTEM?

Is it possible you are getting water in the engine like the details mentioned above.
But also you look at your reed cage for the rear cylinder when you split the cases. If it hydro locked, it usually damages the reeds as well. So if the reeds are damaged,you know that there is hydro locked due to water entering there.


OK,ALSO I NOTICED LEAN CONDITION?

On this issue,i suggest you get the compression tested.as you mentioned it will start with starting fluid but not without that.This indicates low fuel pressure.The compression test done for all the 3 cylinders.
The test should show the 120 psi on all cylinders.If its 110 to 120 psi then its ok.
If any of the cylinder shows less then 90 or Zero Psi then its the problem.


CAN A BLOWN CRANK SEAL CAUSE LEAN CONDITION?

YES definitely it will cause lean condition problem.
It isn't blowing the crank seals out that would cause the seizure. However, a lean condition because they are blown could. You have the air leak at the seals and also reduced to no crankcase pressures to run the fuel pump which could lean out the mixture as well. No matter what, low compression on any cylinder will not let it run.


This details will help.
Thanks.