little help please new boat owner.

[crashzx6r]

I just got A 1980 marquis 17ft fish and ski it has a 120 hp mercruiser inboard outboard sterndrive.

my issues are as follows.

I wanted to know what motor i actually have like 2.5, 3.0 l my serial number is 3579266 on back of motor mercury tag.

My trim does not go up and down, but makes buzzing noise, could it be affected by low fluid, it is easy to push up by hand.

It will turn over constanly but no start.
checked spark plugs they need replaced for sure, rotor button and cap are good, it is getting fuel because spark plugs are wet with fuel, I am currious as to if the boat just isnt getting enough spark to fire up or something else helping, it does speed up and slow down like its trying to start.

my last issue.concern is it hasnt been winterized...temperatures here dont go below freezing and if so not for long overnight at most and havent been below 30. im planning to do it soon but wanted to know how severe it willl be if i wait a little longer? id like to fish this winter but have no warm place to store...is there a way i can drain the water i have sprayed in with muffs trying to crankit or once i get it running?\\


thanks for any help. info in advance i am new to boating but have some mecanical skill.

 

[emckelvy]

Re: little help please new boat owner.

You're in the outboard section, you'll get the help you need over in the I/O section of the forums.

Mods can move this over, or you can re-post over there.

G'luck..........ed

 

[crashzx6r]

Re: little help please new boat owner.

sorry, thanks. just need some help with this stuff....i prefer to try and get some helpful insight or info istead of messin with stuff and makin it worse or harder to diagnose.

 

[Don S]

Re: little help please new boat owner.

One of the other moderators has already moved it to the the IO forum, so that part is done.

If you head up to the Adults Only sticky at the top of this forum, you will find links to service manuals and a lot of other good stuff.
You need service manual #3 for your engine, and #4 for the drive. The drive manual #4 has the troubleshooting procedures for the trim system. hard to say what is "Buzzing" in your setup. Is it the relays or the trim motor iteslf. Or maybe it's the sound of a dirty, loose, corroded connection. Smoke usually follows.

 

[crashzx6r]

Re: little help please new boat owner.

checked the sticky, nothing to tell me what model engine i have. it went back to 81 my boat is a 80 model. i know its mercury I/O 120 hp thats all, so i need to find out little more about it so i can buy parts for my motor... I can get serial numbers if needed, i have one off back of plug side just says mercury, and following number 3579266...

 

[ziggy]

Re: little help please new boat owner.

you seem to know it's a 120. also that the boat is a 1981.

while i'm not the pro here, your serial number is covered under s/m #1. 3770649 and below. which don't make sense unless ya've been repowered maybe. or the year of your boat is wrong. if it's an '81 you should have a hull id number on your transom, likely the starboard side. the last to digits are the year. your drive should also have a s/n. on the sticker. that may help lead you to the year too. one good thing is ya know ya have a mc-1 drive as the 120 used that from '67-'82

you found that s/n on your engine just above the starter and a little to aft?

lack of trim fluid could make your trim inop. many other reasons too.

in that link that dons put you on to. there's also some other good stickys there. like how ign. systems work. in the service manual is a trouble shooting guide for many conditions, like no start and trim system malfunctions. for the engine, myself, i'd start with a compression test, if it passes, then onto electrical, the ign. system, then onto the fuel. them three things are what it takes for it to run. compression, fuel and fire at the right time.

don't temp fate with your freezing temps. drain the water out of it so your safe. you get one freeze for long enough and you won't have to worry about what you have as you'll be getting something else to replace your cracked block. get the water out of it if temps get below freezing at all. better safe than sorry.. the s/m will show you the drain points. i'm gonna guess that it'll be similar to my L6. one drain for the block low at the back, one drain plug for the manifold on the bottom at the back and maybe one on the riser on the back side.

ya gotta get the s/m. it's gonna lead ya in the right direction for servicing... it has the facts in it...

edit, if you have a 120 hp mercruiser. it'd be 153 cid. which is a 2.5L..

 

[rockyman]

Re: little help please new boat owner.

he stated his boat was a 1980 not 1981, just for the record . you still need to check out s/m . good luck .

 

[crashzx6r]

Re: little help please new boat owner.

well, a change of the spark plugs got it running.

i ran it for a bit and then drained the water, and filled the hose leading into the water pump with antifreeze. ill be fishing tommorow afternoon so im hoping a few hours of 29 degrees will not destroy my block, i know it only takes a little water to do it but i have to risk it.

I drained the fuel tank and put a full tank of 93 and a bottle of fuel stabilizer, cleaned and adjusted carb and cleaned up the engine bay some more.

I just have been trying to tune up and clean up somethings, as well as fix a few things on the boat since its my first, and since i dont know conditions it was in or length of time it has been since fluid change.
I plan to change the alt. even though it may work i would rather know its new, i also want to change gear oil and trans fluid.
I have started to loom all the wires and change corroded connecters and terminals. I am hoping by the next couple weeks i can finish the minor tune up/overhaul of minor stuff so i can re carpet and replace seats.

This is my fisrts boat but not my first time using tools...I am a technician for Fontain modification and enjoy working on cars and the frieghtliners at work. the whole boating thing is just little new and unfamiiar to me, cars dont sink and are easy to tow so im weary of repairs on my first boat. I appreciate the ones who have already helped me out with some direction and info.
hopefully i can help you in some way later on. thanks guys..

 

[Lodgepole]

Re: little help please new boat owner.

If you dont know about previous service done, you would be wise to replace the drive water pump impeller. Do not run the engine even for a minute without water to the drive via ear muffs. Also check the drive gear case for water, probably a complete gear oil change would be worthwhile. Water in the gearcase can freeze. Don't kid yourself about temperatures 29 to 32. If you are going to use the boat during the winter, drain the block and minifold every time you take it off the water. And be sure to poke around in the drain hole to be sure crud is not blocking the drain. Study the on line service info or get your self a manual. Give it a good going over and lubing up and you will save yourself a lot if headaches and $$$$$$.

 

[crashzx6r]

Re: little help please new boat owner.

thanks...changed gear oil this morning. im only showing 20 lbs ofd oil pressure on gage while running, below 20 is red zone, when throttle is applied mid ways i runs to 25 to 30 max...i was thinking 40lbs is good pressure...previous owner said he replaced oil pump year ago, im going to change the sending unit on it to see if maybe it isnt doing its job, because theres a unit that looks to be the oil press sending unit with messed up rubber top. with one wire on top center