running ruff after winterization!!

Hello new here...

2004 bayliner 185 w/3.0L

I bought this boat last summer with super low hours and had never seen salt water. It ran all last summer perfect. Winterized it by running antifreeze through and fogged the motor and sta-bil'd the gas (ethanol). So went to start it up...starts every time no problem but WILL NOT IDLE...i have run it about 10 times or so for a total of about 40 minutes i guess, in and out of water with plenty of warm up time...things i HAVE noticed exhaust alittle smokey'er than normal (black) and the exhuast water had a slight translucient milky-ness to it (no froth or emulsion)..it does tend to run rougher than it should but stays running as long as i keep some rpm's in it....i do plan on complete tune up, plugs, wires, cap/rotor and mabey carb rebulid...other than that are there any sugestions????? thanks in advance Moose

I would ask how you winterized the motor. Did you have the motor running when you introduced the antifreeze into the water intake?

If this is so you may not have winterized the motor....................Not the way to do it.

Winterizing a marine engine should be done by draining ALL water from the block and manifold by way of removing all the plugs that are put in place for that specific purpose.

If you are sure about no internal motor issues then remove flame arrestor, clean it with a good rag, next try running it without the flame arrestor and see if the choke is opening.

Is this a TKS carburater?

Pull the plugs and see what they look like............if one or more is wet, Very clean or very different in appearence then that may lead you to the issue.

yes.. i did have the motor running, my particular motor has the block and e/manifold drain hoses..not plugs..and i forgot to mention i removed the thermostat so no passages would be blocked off over the winter(tip i heard from someone) and i think its just a 2bbl mercarb with electric choke

Just for future reference, It is better to just drain the block and manifold and leave it that way than to introduce antifreeze into the intake water and "hope" it displaces the water in the block and manifold.
Far better to simply remove hoses and pour RV antifreeze into them after the block and manifold have drained and the hoses/drain plugs are reintalled/seated/plugged.
Never a need to remove the thermostat for winterizing.........

Winterization for a merc 140 4 cylinder.


1. Add appropriate amount of Stabil to gas tank.
2. Remove lower unit oil fill plug and check for water contamination. If oil looks good reinstall plug. If oil is milky or water comes out, outdrive must be serviced to find bad seal.
3. Hook up water hose to ear muffs and attach to outdrive and make sure outdrive is lowered almost all the way down.
4. Turn on water at hose.
5. Start engine and let run for 30 minutes at ~ 1000 rpms.
6. Turn engine off.
7. Turn water off and remove era muffs.
8. Remove motor plug, right side of engine near oil pan.
9. Poke thru with small screw driver to loosen up all cast and rust so the water flows out steady.
10. Remove the plug in the exhaust manifold, it is under the manifold ¾ of the way back towards the back of engine, poke it clear so the water comes out in a steady stream.
11. Remove the LARGE water hose in the front of the engine where it attaches to the thermostat housing.
12. Remove the incoming water hose and the small hose (that goes from the exhaust manifold to the thermostat housing) where they connect to the thermostat housing.
13. When the water has drained out of the block and the manifold reinstall the plugs. DO NOT over tighten them just good and snug.
14. Have 1 gallon of RV antifreeze ready, pour ¼ of it into the short hose and it will go directly into the exhaust manifold. Pour ¼ of it into the incoming water hose and make sure you hear it come out the outdrive!!! This back flushes the incoming water thru the power steering cooler if present and the transom assembly thru outdrive (you may have to raise the hose up several inches to allow the antifreeze to flow). Pour the rest into the LARGE hose that was removed from the thermostat housing, this goes straight into the motor.
15. Reinstall all the hoses and tighten the clamps.
16. Raise the outdrive to trailer position.
17. Unhook battery and you are done!!

This applies to most 4 cylinder mercruiser engines RAW WATER (not closed cooling systems)

thanks...hopefully i did not jack anything up...and i will follow this procedure NEXT year...Thanks again

Drain the fuel, add fresh fuel, change the plugs and filters. After you know that fresh fuel has been run through the carb and it still not running correctly, it will be time to pull the carb for a freshen up. Make sure the choke is working, if equipped.

OK..now lets talk what to look for if i did screw up....I have checked the oil(dipstick) no evidence of water and no noticeable external motor issues..freeze plugs are inplace (which i know freeze plugs rarely do there job) or wetness noticed while running and black smoke only out of exhaust which is probably carbon being removed by the fogging oil i used and i did run it with the flame arrester off but not sure if the electric choke is doing its job or not...i will read up on that....my recourse now is to drain all gas, change plugs, wires, distr/cap and rotor and then see what happens.....Is it a good or bad idea to shoot some decarb through the carb/intake while its running to blow thing out (hopefully not up)

thanks dockside!!

If all you see is black smoke that is typically unburned fuel.........the choke if working properly will open within 1 minute or so. Open means almost vertical.

If it is staying more than 50% closed try making it open all the way and see if the motor smooths out when warm.......

You may have a fouled plug so maybe pull them and clean them up and see if that helps, if it does throw a new set it.

Is this a TKS engine?

"Freeze plugs" actually, core plugs are not there for protection. They are just there to close up holes used during the casting of the engine block.

OHH ok didn't know that about the plugs...that makes sense then...ok guys school me on the TKS thing...all i know withouth futher investigation is GM 3.0L 181 CID 135HP- 2004 model which i can never seem to find a manual for seems like it always stops at like 98' ...oh and Kghost the butterfly is only opening maybe a .5 inch...no where near vertical

TKS dosent use a choke plate so it sounds like you have a regular carb. remove the flame arrestor and manually force it all the way open. see if that clears the black smoke condition. if yes, this step must be done on a cold engine

save yourself some time, don't bother draining the fuel or anything else till you have looked at the choke. Black smoke indicates a rich condition. Once you have seen that the choke is opening properly, then move on to other items. Always do the easy stuff first before going more invasive. Chances are you fuel is just fine sitting over the winter.

Thanks philipp10...Im a helicopter mech by trade so i know what you mean about easy stuff first