30hp mariner carb problem???

30hp mariner carb problem???

mariner 30hp approx 1990 model 30eo 689 s serial#250287 electric start<br />I haven't used my boat since it let me down last year(bad gas issue) I sprayed carb cleaner in the carb and ran it, it wouldn't idle so i adjusted a small screw on the starboard side of the carb near the top approx 3/4 turn out(it was only 1/4 turn from being all the way in) the engine idled and came up when i hit the gas. today I hit the lake and the engine ran fine high speed slow speed stopped the engine and restarted it everything was great after about a half an hour and running at full speed she began to lose power and sort of rattling(don't know how to explain it) tell tale was spraying water didn't seem overly hot waited for a minute then restarted it had to give full throttle to get it going would not run good at ful throttle so I headed for the lauch at slow speed half way back i tried it at full again it was Ok for a few minutes the lost power and rattled again so waited and restarted chugged along for home. when i was almost at the lauch i gave her again at it lost power and died it did want to start very sluggish on the starter which never happened the other times so my buddy was about to tow me the last few hundred feet and I got it going. Brought it home and it runs not badly in the driveway with the muffs on any ideas PLEASE HELP KEN COULD IT BE AND ELECTRICAL PROBLEM AND NOT THE CARB AT ALL??

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Hi,<br /><br />I believe I have a similar engine to you, mine is 30AM 689 series 1980s model.<br /><br />The manual I have covers 1977-1989 and I think the screw you adjusted on your carb is the "pilot screw" which my manual specifies should be 1 and a half turns out from barely seated.<br /><br />Have you got a manual for your engine? They are essential when working on your outboard - this cannot be over-stressed! If you don't have one get one you'll be glad you did.<br /><br />If you've had a problem with bad fuel have you tried cleaning out the carb? I really recommend cleaning it out thoroughly by disassembly, carb cleaner and most importantly compressed air.<br /><br />Hope this helps,<br /><br />Dan.

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Thanks Dan Thanks for the info 1 1/2 turns is what i turned my screw too . I did take the carb totally apart and cleaned it all out after the bad gas I almost believe the problem is electrical or something other than the gas Thanks any info you can supply is appreciated Ken

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Did the engine over-heat? You say the problem occurred after some time out on the water. Also that a strange sound appeared and the starter was sluggish turning the engine.<br /><br />This sounds like over-heat and/or lack of lubrication. Especially since it seems to run fine on returning home when it presumably had time to cool?

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

The tell tale seemed to by working fine and the engine was not overly hot to the touch so i don't think the engine overheated. The last time when the starter had trouble thats what I thought as well but I don't think so. I actually never gave it more than a minute or two to cool not like it sat for an hour or anything. I was wondering if you could forward the page from your manual on replacing the impellor so I know exactly which bolts to undo kaltireman@yahoo.ca that would be helpful I have to try today to get my own copy of the manual we don't have a mariner dealer so it may take some doing thanks Ken

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Whenever you disassembled your carbs, did you make sure that your jet isnt clogged? All you have to do is blow air where the fuel line connects to your carb and see if a perfect flow of air comming out inside the carbs. If not, a really tiny piece of trash is causing a bad fuel flow.<br /> While you have the fuel line loose, try to start it and check to see if fuel is pumping good from the fuel pump.Your fuel pump diaphram could have a hole in it. Its an easy and cheap task to rebuild a fuel pump.Around $4.00 for a diaphram kit.<br />Also, do make sure your jet screws are set to specifications. That means alot. <br /> It these suggestions are not the issues, You could be having an electrical problem. With it running fine one minute, and bad the next, its hard to determine the problem. Run your motor until the problem happens again and immediatly disconnect your spark plug wires. Hold the wires over the plugs and look for a good spark on each of your plugs.<br /> The elecrtical system has fairly simple parts. In order, it has a Stator thats under the flywheel, Switchbox, coils, and spark plugs. My guess is it could be the stator or the switch box, that is if its an electrical issue. <br /> I hope my suggestions help point you in the right direction. Sorry I had to type so much...

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Oh yeah, by the way, have you ever heared of something called sea foam? This is some good stuff. <br />I have a 75 70hp motor that I had recently rebuilt. Rebuilt motor, carbs, electrical system, fuel system, and all that good stuff. She ran pretty good, but not 100 % until the other day. I had purchased this stuff at napa, about $6.50 an arisol can. Took my plugs out, sprayed it in each cylinder, let set for an hour, and started it right up. sprayed it in each carborator and watched all kinds of stuff blow out of my exaust. I took her out on the lake that evening and she came out of that water like there was no tommorrow. I guess this stuff cleans your engine out.It will smoke really bad when applyed, but thats good. Kind of like having your fuel injectors cleaned on your car.<br />I hear people talk of this stuff on this site frequently, and how good it is. If it doesnt fix your problem, it would be good to have used it in your motor anyway. I hear that its good to use 1/2 can per 3 tanks of fuel. Just spray it in your cylinders, let set over night, and spray in your carbs while running. <br /> Gotta think on how nasty 2 cycle engins can get.

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Hi,<br /><br />I'd be glad to send you the info from the manual if I can be sure it's the right info!<br /><br />You say your engine is 1990? Well the manual I have covers up to 1989. Are you sure it's 1990? It might have significantly changed I don't know.<br /><br />Check and let me know!<br /><br />Alternatively, a useful source of exploded diagrams is mercruiserparts.com <br /><br />Try this URL :<br /> http://www.mercruiserparts.com/select_models2.asp?type_id=MAR <br /><br />Cheers,<br /><br />Dan

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

I have purchased a new impellor the old one is missing a tip or two anything I should do to make sure they are out of the system? I took the thermostat out everything looks good there no chuncks> so I will install that and see what happens Nothing on the sides of the engine looks discolored or paint cracking so I don't think it overheated cross your fingers for me I'll let you know Thanks

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

If you need any info from that manual mail me dan@danandjane.com.<br /><br />I've heard a very light smearing of oil on a new impeller is a good idea to make sure it doesn't get damaged on first ever start.<br /><br />Good luck,<br /><br />Dan.

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Dans right, I use a little axle grease and smear it since it sticks better.

Re: 30hp mariner carb problem???

Re: 30hp mariner carb problem???

Thanks for the info guys keep it coming I got a new impellor WRONG ONE had to order from Toronto other side of country hopefully see it courier tomorrow the parts woman told me to put vaseline on it before I stick it in and when a women tells me that I surely will LOL I had a heck of a time getting the large nut off the gear linkage it was a bit rusted but a little Move It and some heat from a little butane torch she actually came loose<br />I will keep you posted and may take you up on the offer Dan for emails from your book Thanks about the Sea Foam I have to call the parts place and see I was wondering after you use it does the engine become dependant on it (like either on a diesel engine) won't want to have a either bunny on my hands let me know Thanks Ken