Cold start vs. Hot start???

[mattdoran]

My 02' 130 2-stroke, Yam w/carbs, is hard to start when its has been sitting for 20+ minutes while the engine is hot. Cold start is OK, starting after stopping for a short time is OK, just after sitting for a while well hot or "warm" it becomes difficult. It can take over a minute+ of cranking to start sometimes.

I was having cold start issues, but realized I wasn't lifting the neutral throttle that the manual recommended while starting...no more cold starting issues.

I shouldn't have to "throttle up" while starting warm should I????

It will also bog down rarely now, when planing out the boat...but it does happen once every other outing.

I've really tried an exhausting list of remedies for my issues and it runs better, but I would still like to eliminate the starting difficulty. The engine is a brut 95% of the time...its that 5% thats eating at me.

I've triple checked electric/manual choke operation, shock treated w/seafoam, new gas a few times, seafoam in tank, then stabile in tank, checked battery cables, fuel filter, plugs, new fuel pump and primer bulb, removed carb bowl drains sprayed w/berrymans (looked very clean), removed one carb to double-check (looked very clean). The "pisser" flows strong.


Does it sound like I'm fouling plugs?
Any special hot-starting procedures?
Anyone have similar issues/recommendations?

[jonp]

Hi MAtt,
I had an issue like this with an old Merc 50 hP many years ago, turn out to be a combination of things, bad primer bulb, and weak fuel pump, I don't think you have the same issue since you replaced this... Do you use ethanol where you are located? Do you have a water separator in your system? If not check for water in the tank, and definitly install a water separator with a 10 micron filter. I use a Racor/merc replacement on my 90HP. I would also drain your carb after you check for water. You may have stuff junk sitting in the bottom of the bottom of bowl that seafoam wont get out. Regardless it Won't hurt to drain them, just don't on get the stuff on your hands, and have plenty of paper towels on hand as it drains. I have experienced water problems with various outboards and they all seemed to start fine and run for a short while and then you get screwed after your way out there in the water... BTW once I start my 90 I am good for the day, never need the cold start. I don't even prime blub often when it cold...

I am sure other will add to this. Good luck Jon

[jonp]

just noticed you did drain carbs, sorry One other thing I did not mention, I also experienced this twice, both with mercs, 1979 85hp and 1985 175hp. After these got guys hot the tempature would do something to the CDI/switch box, and not run properly, not normal. Had to have them changed and problem went away... Both was very expensive... The 85HP would run for hours before it would hicUp... and both would be hard to re-start ran like sh_t. Others will hopefully be able provide more guidance. Perhas there are tests for the YAM CDI?

Jon

[Ken]

Matt,
Next time out and after the motor has set for the "20+" minutes, try squeezing the primer bulb several times until hard before starting. Maybe this will give us a clue as to what is going on.
May be that the fuel is draining back down into the tank during that 20 minutes - it does on mine, but it takes several hours.
With my 2000 C115 (same V-4 as yours and carbed), if I try to restart, say, within an hour after shutdown, all I have to do is hit the starter and she fires right up - no choke, and throttle at idle. But if it has been more than about an hour,
I have to raise the throttle a little above idle and give it some choke till she fires.
I've been told that every carbed Yamaha V-4 is a little different when it comes to getting them started - you just have to learn what you motor wants when it's cold and when it's warmed up.
Hope this helps [img]smile.gif[/img] ,
Ken K

[mattdoran]

Wow, Jon and Ken thanks for the valuable information. I'm 90% sure the boat does not have a Racor seperator. My 95' Skeeter fuel tank is "shoehorned" in there and I cannot see the whole line. I've heard many stories on this site and people recommending Racor's as a preventative device, but no stories like yours Jon resulting in a solution. It was good to hear.
Wouldn't water in your tank affect the engine at all times...not just hard hot starting??

I hope its not a CDI/switch box as mentioned.

"Heat soak" is a common problem on carbuerated cars, like my edelbrock carb. I believe it boiled the gas before I installed a thick seperator gasket. Can the same happen to the CDI?

Ken I have yet to check the primer bulb for softening up. All I know is its soft by the next outing...obviously. If the primer softens up after 20 minutes, does that inply an air leak or something? The bulb is brand new.

Maybe I have to learn what she wants when hot, but I know for sure I cannot just turn the key when sitting for a while. It seems there is a fine line for how long it can sit.

[mattdoran]

Oh......I've tried ethonol free, and with ethanol if the station doesn't have free...no noticable differances.

[jonp]

Hi Matt,

You have few questions... Ken's suggestion is good one to try first as this may point you in the right direction. Fuel pump replacement is not a big deal. The CDI is the last resort at which point I would have it looked by tech. There may be tests for the CDI today.

I have not heard of heat soak, but I have noticed (on other outboards) that very hot sunny days the primer bulb would seem to empty out quickly particularly if I was just idling around or sitting for while. This was happening on my older Merc outboard, could be just a fluky thing. Just gave it a few pumps and it was fine.

Ethanol will not really affect the way you run until the engine sucks up the junk at the bottom of the tank. Gas/ethanol is lighter than water and always floats on top, the water and gelled up junk settles to bottom and will get sucked up as you run and hopefully get trapped in the water separator. As your carbs get filled with this stuff it will go into the engine and have big impact on the way it runs. I have not any big issue so far with my 90HP although I did have to drain the carbs at one point because it did start running very strangely. This was just after purchased it in July, and immediately after I installed a water separator and cleaned to bowl/filter. It did have signs of dirt and water, and may have had residual stuff sitting in the carb. I now am watching carefully.

I did have and issue very early in the season with my 25 Yam. Running at WOT then died, (of course out in the middle of the lake) had to pull it about 50 times before it would start again and kept it running with the choke pulled.. Didn’t know what happened until I pulled the little bowl filter and found it filled with stuff other than gas... This was an fix because of the small portable tank.

Hope this helps, good luck

jon

[slim]

have you checked your idle timing? what is it and i will look it up and tell you what its supposed to be. this could have a big effect. what i would check first is does the motor have fire when it wont start. this too is an easy check. just pull the #1 cyl. wire off while having someone turn the key. but dont grab it with your hand unless your brave. youll find out very quick if its got fire or not. try this first. if it doesnt have fire then i would try a new cdi. i have run into a few cases where this same problem has happened with a v4.