need help troubleshooting 82 merc 80 thunderbolt

[lostintexas]

outboard had sat about 4 years.<br /><br />upon getting the engine, i removed the spark plugs and poured oil in all four cylinders and spun the engine by hand several times. at that time it was late so i let it sit overnight.<br /><br />the next day i went and filled the gas tank with premium gas (as said in owners manual) and mixed the oil and gas 40:1 ( thought that after sitting a little extra oil would help with the inititial re-break-in. hooked the gas lines up and turned the key, it sputtered a couple of times and started right up on the hose and ear muffs.<br /><br />took it to the lake the next day and it again started right up, so the adventurer i am, i took off across the lake. i made it to the other side and the motor seemed to loose power. I let off the throttle to turn around, and the engine died. it would then not restart. after a tow-in, i brought the engine/boat home and finally got it to start again but it will run only with the idle srews 1 turn out and real rouph. <br /><br />i have replaced the spark plugs and primer bulb and hose(was leaking, i thought it may have been sucking air). i added seafoam to the gas and did the arosol can as well (this helped a little - lots of smoke). the primer bulb stays stiff. pumping the primer bulb while running does not help.<br /><br />any links or advice will be helpfull. i am competant on 4-stroke motors and carbs so i am confident that i can take what ever apart and restore it to its original state.<br /><br />sorry for the long post, i just wanted to include as much info as i could. thank you for your time and energy in advance.

 

[jimalsk]

Re: need help troubleshooting 82 merc 80 thunderbolt

lostintexas you hit the nail on the head when you mentioned it sat for 4yrs. Chances are the carbs need to come off and cleaned internally.They are more than likely varnished up and need a bath and air shot through them. You should also replace the water pump, after years of sitting out of water the impeller is probably stiff and cracked.

 

[lostintexas]

Re: need help troubleshooting 82 merc 80 thunderbolt

i will pull the carbs as soon as it stops raining. only rains here when i want to work on something outside.

 

[jimalsk]

Re: need help troubleshooting 82 merc 80 thunderbolt

That's the way it works all over

 

[Barnacle_Bill]

Re: need help troubleshooting 82 merc 80 thunderbolt

Sometimesm I think that is the law. LOL

 

[lostintexas]

Re: need help troubleshooting 82 merc 80 thunderbolt

there was a break in the weather so i got the carbs off and on the kitchen floor apart (yes the wife is exited about this)<br /><br />first observation. all the hoses are hard as a rock. i will go to the parts store and buy some new fuel line and clamps (they were secured by tie-wraps - i wonder still if air was being sucked in?)<br /><br />idle screws are in good shape, not flat as i suspeted.<br /><br />float needle are in good shape, not concave as i had suspected. floats are not full of fuel.<br /><br />gaskets i think had been re-used before, pretty beat up. i will hit the merc dealer for some new ones monday.<br /><br />no sand in them as i had thought there would have been after sitting so long.<br /><br />i ran a thin wire threw all the passages i can get to and then blew them out. i did get some grunge out of a couple but not as much as i expected, although it may not take much.<br /><br />anything else i need to check before re-assembly? what are the float specs if any and where to measure from? should i buy a new float and/or needle just to be safe?<br /><br />gas tastes bad, even old/burnt coffee will not kill the taste.<br /><br />thanks for the help so far, i am in debt to you.

 

[b20]

Re: need help troubleshooting 82 merc 80 thunderbolt

those tiewraps are special,not just normal ones.or should be.the mercury part number for them is 54-816311T.after sitting for 4 years i'd be changing the water pump too.and some new diaphrams in the fuel pump.sour gas will also kill the engine pretty quick.if it's more than 6 months old,use it to kill weeds in the garden.wife WILL love that.

 

[lostintexas]

Re: need help troubleshooting 82 merc 80 thunderbolt

i will take the advice, i will get the water pump and fuel pump kits from the merc dealer when i visit there later today. the gas i put in it was new and fresh mixed, i am unsure of anyone else. the carbs were pretty clean and after soaking in carb cleaner overnight are even cleaner. i have two tanks, one has fresh fuel, the other has four year old fuel, i think the city has a disposal tank i can dump the old stuff in. i just dont want to dump it out on the ground. <br /><br />thanks for the help. with it i will get this engine running like it was meant to, not a piece of yard furniture.

 

[lostintexas]

Re: need help troubleshooting 82 merc 80 thunderbolt

ok, what did i mess up?<br /><br />put pump back together and i cannot prime the engine. i thought i took the old gasket off and put the new on in the same way as the old came off. <br /><br />when i pump the primer the bulb is hard and does not prime the engine. i removed hose from pump and can pump gas but after the the pump there is no gas. i removed the pump and when i press on the primer bulb it does come out the valve. what did i do wrong?

 

[Clams Canino]

Re: need help troubleshooting 82 merc 80 thunderbolt

Check valves go on backwards? <br /><br />-W

 

[lostintexas]

Re: need help troubleshooting 82 merc 80 thunderbolt

<br />Check valves go on backwards? <br />

yup, i even impressed myself this time. i took it apart one piece at a time to make sure i put it back exactly the same as it came apart and still managed to put the top check valve in backwards.

 

[Clams Canino]

Re: need help troubleshooting 82 merc 80 thunderbolt

(Take's a bow....)<br /><br />-W