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Mercury 75 wont start

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k3v1n123

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"Hi all this is my first time

"Hi all this is my first time here for posting hope someone can help me ..

My problem is i have just bought a boat with a mercury 75 outboard on it im not sure of the year but i have the manual and its says 1986 but it could be a little newer ? The boat had a service 3 years ago and since then has never been started and has been in storage for all that time, Should i get it serviced or would it be ok just to start. I have checked that it engages gears properly and it seem ok.

I connected a battery but all i get is a clicking noise the starter moves up but wont get it started could the battery be broken ? I had it runing for a few seconds but i had to use the pull cord and by turning the key at the same time it sort of started. Any ideas what it could be ??

Thanks

Kev."
 
Try a different battery if it

Try a different battery if it does the same thing the starter is bad. I would lube the cylinders good with two stroke oil if its been setting that long before cranking it a lot.
 
I assume your asking about lub

I assume your asking about lubing the cylinders. Take a good spray bottle fill it with 2 cycle oil and spray in spark plug holes then turn over by hand to lube the cylinders. If the cylinder walls are dry and you crank it a lot it could cause ring problems/damage.
 
Ok i have lubed the bore and i

Ok i have lubed the bore and i have put on a new battery this is a car battery it turns over it fired up once then cut out straight away the battery has now died so i have put it on charge. Any other ides what i could do or check that it is working fine.
 
"Hi just an update on this had

"Hi just an update on this had another play about with it and its now running it has a bit of smoke coming from it not a lot but its not like it should be, Could there be to much 2 stroke oil in it?

Regards
Kevin."
 
"smoke is normal for a 2 strok

"smoke is normal for a 2 stroke, wait till you give it some real power runs, it will get better. Just make sure the carbs are clean. And don't worry if it drips some black oil out the bottom."
 
"Right a small problem i have

"Right a small problem i have come across im not sure if this is normal i have been doing a bit of on the boat itself so have not had the boat actually in the water been startin git for a minute ot two at a time with the flush muffs on it. The problem i have is its takes about 30 seconds to a minute to start first thing but when it starts and i switch the engine off it will start first time with the key. I have tried giving a bit of choke but it doesnt seem to do anything i can hear it clicking though,

Thanks
Kev."
 
"Are you pumping the fuel bulb

"Are you pumping the fuel bulb for the first start up?
It could also be flooding, you can pump the fuel bulb and look down each carb with engine off, any drips out of carbs is bad. Flooding can cause excess fuel to build up in engine, fuel evaporates and leaves oil behind= smoke on start up."
 
Alright jb yes am i pumping th

Alright jb yes am i pumping the bulb first i will check carbs tomorrow and see if its flooding .. how do i get to the carbs is there anything that will need removing ?
 
"Hi just an update on this i t

"Hi just an update on this i took the boat out for the first time on monday got it in the water lowered engine using the power tilt went to start just kept trying to start nothing happened tried this several times eventually flattening the battery.

I took the battery off my van tried again but nothing so i took out the spark plugs gave them a clean because they looked oiley but they were brand new plugs only put in the other week tried again but nothing again.

I then took out the plugs again but i put a little bit of petrol in each bore apart from number 4 which i couldnt reach put the plugs back in turned the key and it went first time booted up no problems left it running for 10 minutes switched it off i then left it for 10 mins turned the key fired up first time went up and down the
river for a about an hour no problems at all, I come back switch if off have a little sit down another 10 minutes later go to start it wont start so i result in taking out the plugs again pouring more fuel into the bores put the plugs back in and it boots up again.

Im not sure what the problem is but im sure someone on here should be able to help ;) ..

I have noticed a bit of oil sitting just under the carbs (see picture) also the plugs seem very oiley also see pictures attached sorry about the long essay
..

Regards

Kev.

293250.jpg
"
 
"Hi,

My 2c's worth, rep

"Hi,

My 2c's worth, replace the impellor. Been standing 3 yrs? Bound to fail on you. Sooner than you think...

Clean the carbs and you'll be sorted.

Is the fuel fresh? Mix right? 50:1 is right.

BTW, smoke is good, means oil is doing it's job!

How's the compression?"
 
Thanks for the reply is it bes

Thanks for the reply is it best for me to take this to a marine engineer ? I can do basic mechanics on a car like a service etc i know its now like a car engine i was using that as example ... How do i go about changing the impellor is there a how to anywere i have no idea how to clean the carbs do they need to be taken off ?

Yeah the fuel was also fresh 50:1 i also did ..

There was a little smoke from the exhaust .. I would have to buy a compression tester to check the compression though ..
 
"By the looks of the plugs the

"By the looks of the plugs the engine is running on 1 carb. As I said earlier, remove and clean carbs, now add a compression test to see if there has been damage by running it. Check spark on all 4. Check and see if the choke works. It might not start because the carb isn't getting fuel."
 
"Hi JB i borrowed a compressio

"Hi JB i borrowed a compression tested and did the test on 4 cylinders it was 125psi on all of them and all.
I also checked for sparks and all 4 spark, When i press the choke you can see the valve lifting up so that works.
I did the compression test when the engine was cold im not sure if this is the correct way of doing it or not but i didnt want to be putting fuel staright intop the cylinder again to it going incase it caused any problems if this the correct way to do it the only thing as you said it could be is the carbs. I have also ordered a set of new plugs just incase they never had them in stock so they had to order them and they take a few days so hopefully i get it going once the carbs are clean with these other plugs and then keep my new ones as spares.

Has anyone got a service manual how of how to remove and strip the carbs?

Regards

Kev."
 
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