What to do next?

[DuckFan]

I needs some help deciding what to try next to fix my problem. Here is the complete story. I am sorry about the length:

I have a 1992 Mercury Mariner 60hp that I am having power and ignition issues with. The problem only seems to exist when I have been running the motor for a long period of time and working it hard such as running out in the ocean. The problem acts like a fuel demand issue. The motor will run along fine but then after a while 30 min or so, it will hiccup and stop. Then it I will start it back up again and hit the throttle only to have it sputter and die. Then I will start it up again and ease the throttle to about 1/4 but then when I give it any more it will sputter and die. I have completely gone through the fuel system including filter, pump, and even drained the tank. It seems to be getting plenty of fuel. I put brand new spark plugs in for this last trip out where it acted up again. I am wondering if it might be related to the coil or other ignition parts. It only seems to do this after it heats up and has been running for a while. If I let it cool down and get cold I can run it again for a period of time (30 min) before it starts acting up again. I have only experienced this problem in big water such as the ocean or bay.

Common opinion at the time suggested that it was the stator which without testing the old one I just replaced. I tested the boat and motor out on a large river (fresh water) and it seemed fine. However, I took it out fishing in the ocean (salt water) and at fist there was no problem on the first day. The second day there was a small issue but it did not seem to be the same as above. The 3rd day it definitely was acting as above once again. This has become very frustrating to fix because despite having it in two different shops they cannot seem to recreate the problem so they cannot fix it. I have the following questions for any of you who wish to help

Now that I have replaced the stator would you suggest something else? Could it be another electrical component and if so which one?

It seems to only happen in big water especially if it is salt. I have never had this problem in fresh water. Could there be something to the salt water?

Could my problem be related to fuel or carburetor? If so what to should I try?

Again sorry for the length of the post I just wanted to give all the details in hopes someone can help me.

Thanks again
DuckFan

 

[achris]

Re: What to do next?

Ok... That's a goodie...

Salt water would suggest an electrical element. Start by checking control box harness for any signs of water ingress. Pull the cover off and look at every single wire to see if it's chaffed and may be touching the engine block. Check every single connection and junctions for possible tracking to ground.

Do you have a RED stator or a black one? Pull the regulator and check it thoroughly, it may be cracked or damaged in some way that only becomes a problem when hot.

Check the coils, again for hairline cracks.

So I can see exactly what engine you have, can you post the engine serial number....

Chris...........

 

[saumon]

Re: What to do next?

Definately an heat related issue. May be stator, coils or also switchbox. You'll need 1) a DVA meter and 2) an OEM service manual, as electrical troubleshooting procedures are very engine specifics.

Here's the manual for your engine (serial 0D000750 and up): http://rapidshare.com/files/213240341/45jet-50-55-60.rar (password to open each section is "ribforum")

 

[DuckFan]

Re: What to do next?

Ok... That's a goodie...

Salt water would suggest an electrical element. Start by checking control box harness for any signs of water ingress. Pull the cover off and look at every single wire to see if it's chaffed and may be touching the engine block. Check every single connection and junctions for possible tracking to ground.

Do you have a RED stator or a black one? Pull the regulator and check it thoroughly, it may be cracked or damaged in some way that only becomes a problem when hot.

Check the coils, again for hairline cracks.

So I can see exactly what engine you have, can you post the engine serial number....

Chris...........

Chris:
The engine Serial number is 0D151514 if that helps. Also do you think it could be fule related such as the enrichment valave?
DF

 

[HD Fatboy?]

Re: What to do next?

Chris:
The engine Serial number is 0D151514 if that helps. Also do you think it could be fule related such as the enrichment valave?
DF

You could disconnect the wires to the Enrichener Valve to see if helps or hurts. Prob will not help with cold starts

 

[achris]

Re: What to do next?

Chris:
The engine Serial number is 0D151514 if that helps. Also do you think it could be fule related such as the enrichment valave?
DF

An enricher valve problem (leaking) would be more obvious at low speed. You say you have no problem at 1/4 throttle or less (when the problem manifests).

You could clamp the enricher valve hoses and try, but I think you'll still have the problem. I think it's electrical, but a nasty to find. The nicest thing that could happen is the engine started played up all the time. I really don't like intermittent faults.

Chris........

 

[DuckFan]

Re: What to do next?

An enricher valve problem (leaking) would be more obvious at low speed. You say you have no problem at 1/4 throttle or less (when the problem manifests).

You could clamp the enricher valve hoses and try, but I think you'll still have the problem. I think it's electrical, but a nasty to find. The nicest thing that could happen is the engine started played up all the time. I really don't like intermittent faults.

Chris........

Chirs:
Thanks again for your reply, Yes this is a real bugger of a problem. It only seems to happen in heavy (and so far salt) water too like the ocean or large bay. Not the kind of place to fool arond testing things. When the probem occurs it acts like the engine is not getting any fule. It was suggested that it was a choke issue beause it acts like the engine is choking out when you demand power. it will start, idel, and run fine at about 1/4 throttle as long as you ease it along. The minute you push the throttle any more it sputters and dies. But let it cool off completely and it will run fine for about 20 minutes then it starts again. Thought it might be a fule pump but the ball stays hard all the time pumping it makes no difference. Thought it might be filter so all were replaced but still had the problem. What would you say about heat sensor? could that be it and it is shutting things down prematurly?
Thanks again
DF

 

[DuckFan]

Re: What to do next?

An enricher valve problem (leaking) would be more obvious at low speed. You say you have no problem at 1/4 throttle or less (when the problem manifests).

You could clamp the enricher valve hoses and try, but I think you'll still have the problem. I think it's electrical, but a nasty to find. The nicest thing that could happen is the engine started played up all the time. I really don't like intermittent faults.

Chris........

Definately an heat related issue. May be stator, coils or also switchbox. You'll need 1) a DVA meter and 2) an OEM service manual, as electrical troubleshooting procedures are very engine specifics.

Here's the manual for your engine (serial 0D000750 and up): http://rapidshare.com/files/213240341/45jet-50-55-60.rar (password to open each section is "ribforum")

Saumon:
Thanks for the link on the manual. Is there a trick or softwere I need? I downloaded it but can't get it to open. Also, just to try and rule one thing out on this issue I have already replaced the Red Stator that was on it with a CDI Electronics Stator. They say those are better than the original. After installation I tested the engine on the river and it worked great. So I was hoping to find the next component to test...any suggestions?
Thanks again for your help with this
DF

 

[Faztbullet]

Re: What to do next?

What type of hull and material? Do you have a voltmeter on dash and if so is it overcharging? Do you have a battery selector switch? Have you checked spark when it was acting up as the 1 piece switchboxes are a pos and can cause weird problems...

 

[achris]

Re: What to do next?

Saumon:
Thanks for the link on the manual. Is there a trick or softwere I need? I downloaded it but can't get it to open. Also, just to try and rule one thing out on this issue I have already replaced the Red Stator that was on it with a CDI Electronics Stator. They say those are better than the original. After installation I tested the engine on the river and it worked great. So I was hoping to find the next component to test...any suggestions?
Thanks again for your help with this
DF

What software are you using? I use 7-Zip and don't have any problems, just open with "Extract files..."

 

[DuckFan]

Re: What to do next?

What type of hull and material? Do you have a voltmeter on dash and if so is it overcharging? Do you have a battery selector switch? Have you checked spark when it was acting up as the 1 piece switchboxes are a pos and can cause weird problems...

Faztbullet:
The hull is aluminum. I do not have a voltmeter on the dash so I don't think it is over charging but I can't tell. Would that mean I have a bad charging component? I don't have a battery switch just the one battery. It is hard to check the spark with it is acting up as it only does it intermittently and at high speed. When it is acting up I have check the spark at low speed and there is plenty. I have given thought to the switch box as it would make sense. But as you know they are spendy and I wanted to make sure I didn't have another issue. Is the switchbox something that could be tested by a shop? Would you suggest just replacing it?
Thanks for your help
DF

 

[DuckFan]

Re: What to do next?

What software are you using? I use 7-Zip and don't have any problems, just open with "Extract files..."

I don't have that software so thanks I will get it
DF

 

[Faztbullet]

Re: What to do next?

Install a voltmeter on battery and check voltage when running ,if overcharging the rectifier/regulator is having problems and likely overheating stator. You can install a timing light to a cylinder and close cowl to check spark at WOT.