1993 mercury outboard 200hp loading up when started cold

[keyhop20]

Need help trouble shooting 1993 mercury outboard 200hp (black max) NOT EFI. The problem Iam having is when I start up the motor cold it seems to be loading up like running to rich ...after it warms up it idles fine, the motor is oil injected ... also when the motor is hot and you shut down for awhile its hard to start back up!!!! any suggests ........???

 

[clanton]

Re: 1993 mercury outboard 200hp loading up when started cold

I would start with checking the compression, then the ignition system.

 

[KIWI MERCMAN]

Re: 1993 mercury outboard 200hp loading up when started cold

keyhop20 <br />That model has a air valve on the starboard cly head that is closed when the engine is cold, as this model always ran lean on start up before they fitted the air valve. as the engine warms up this opens and leans off the fuel to the carb idle mixture circuits. If you follow the 1\4" black hose from the starboard side of your carbs you will find it, when the engine is cold you should not be able to blow through the hose at all, when hot you can blow through it no probs. The other thing would be running temps, themostats etc as if the enige is running cold they will take a long time to burn off that cold fuel.<br /><br />Hope this helps.<br />Kiwi

 

[keyhop20]

Re: 1993 mercury outboard 200hp loading up when started cold

KIWI, thanks for the info but the valve seems to be operating properly .. I was able to blow through the valve when it warmed up..Do you think I have a problem with the oil injection system..? I also noticed the primer bulb was not staying hard (primer bulb not to old)not sure if this has any thing to do with my problem....KIWI sounds like you no a little bit about this motor .Are you a marine mechanic????? ps you don't half to answer that .... Iam automotive mechanic for general motors .. I appreciate the help thanks again!! KEYHOP20

 

[KIWI MERCMAN]

Re: 1993 mercury outboard 200hp loading up when started cold

keyhop20<br />Yes I am but dont tell anyone oK, how many hours on this engine,have you had it since new? Is this something that has just started or has it been getting worse?<br />What about your comps?<br />I'm assuming you have checked all the basic's,good fuel, plugs, timing etc.<br />One thing I always found with V6 merc's is that you can have good comps, 120 to 140 psi but still have a problem, so we always used to take off the heads and have a look, for the cost of 2 head gaskets it can be well worth it.<br /><br />Kiwi

 

[keyhop20]

Re: 1993 mercury outboard 200hp loading up when started cold

kiwi , I have about 600 hours on the motor in the five years I owned it.. also boat and motor well maintained . The problem with the motor just started about a month ago .fuel good,plugs new,compression 125 psi with engine warm ,timing 20 deg.BTDC . If I pull heads off ,what I am looking for??? or do I even have a problem there?? KEYHOP20

 

[KIWI MERCMAN]

Re: 1993 mercury outboard 200hp loading up when started cold

keyhop20<br />Ok, have you had your fuel pump looked at, could it be leaking into the engine? They will if the diapham has split, What about your reeds? these can be checked by puting a psi gauge on the check valves and see if you have 3 to 6 psi and steady, if not then you could have a reed out.<br /><br />I'll check back later as have to fly at the moment.<br /><br />Kiwi

 

[keyhop20]

Re: 1993 mercury outboard 200hp loading up when started cold

kiwi thanks for the info, but I have not had a chance to get back on it .I have been very busy, when I get some info for you I will get back to you okay!! I really appreciate the help.... keyhop20

 

[robalofish]

Re: 1993 mercury outboard 200hp loading up when started cold

Hello ,<br />This is almost 100% exactly the symptoms of my engine with exception of the hard to restart indication. I did try the reed check procedure and was only seeing 1-2 psi max with a lot of pulsation. Am I checking this the right way?<br />1. engine warm<br />2. idle speed on the flush muffs.<br />3. pull hose plug pres gauge on port.<br /> <br />Thanks for any assistance on this.<br /><br />Engine info:<br />1994 Mercury 200hp Carbed 600 hrs.<br />125 psi compression all cyls.

 

[shelbydriver]

Re: 1993 mercury outboard 200hp loading up when started cold

do you tilt your engine up while traveling. Maybe its leaking a little extra fuel in there and it may take a while to burn off.