1981 200hp merc, hard time starting, ignition question

workaholic

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Hello!

I have a 1981 Mercury v6 200hp. I have a really hard time starting it from cold, sometimes it almost kills the battery from trying to start it for so long. Once i get it going it doesnt run on all 6 until it warms up (after roughly 5 minutes of riding). I took a compression test and i am still at 125psi across the board. Its getting fuel because it sometimes floods itself from trying to start it for so long.

My guess would be bad coils or other electrical, and not carburation based on the fact that once it warms up it then runs on all 6 cylinders and runs beautifully. And pretty much follows the same pattern every time from cold.

What do you guys think?

Also what year and models are the coils interchangeable from? would coils from a 1997 v6 135hp work on my 1981 200hp?

Thanks for all your help in advance, much appreciated.
 

workaholic

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Re: ignition coil and starting questions...

Re: ignition coil and starting questions...

anyone?
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

any help would be greatly appreciated.. i am even having a hard time finding an oem shop manual on ebay for my year and model. Information for my year and model seem hard to come by..
 

MarshMan73

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Re: 1981 200hp merc, hard time starting, ignition question

I hope you find out the problem before I throw my motor away. Mine does the same thing you describe and I still haven't found it, but my compression is much lower than yours so figured it was that.
 

bigshrimpin

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Re: 1981 200hp merc, hard time starting, ignition question

Hello!

I have a 1981 Mercury v6 200hp. I have a really hard time starting it from cold, sometimes it almost kills the battery from trying to start it for so long. Once i get it going it doesnt run on all 6 until it warms up (after roughly 5 minutes of riding). I took a compression test and i am still at 125psi across the board. Its getting fuel because it sometimes floods itself from trying to start it for so long.

My guess would be bad coils or other electrical, and not carburation based on the fact that once it warms up it then runs on all 6 cylinders and runs beautifully. And pretty much follows the same pattern every time from cold.

What do you guys think?

Also what year and models are the coils interchangeable from? would coils from a 1997 v6 135hp work on my 1981 200hp?

Thanks for all your help in advance, much appreciated.

Typical for that motor . . . 81 should have the enrichener . . . make sure it works. 79/80 200 was a vertical reed with flapper choke.

To start that motor . . .

0. make sure your battery is fully charged.

1. Prime the bulb
2. Tilt the motor all the way down
3. advance the throttle
4. Press the choke . . . listen for the click . . . count to 5 and turn the key with the choke press in.

Also sometimes old worn out starters have trouble spinning the flyweel fast enough.
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

what and where should i be looking for on the enrichener? what exactly is its purpose?

I have a brand new battery on it and it seems to be spinning the motor fast enough. As for the choke, it clicks and works, i pulled off the plastic intake casing to make sure al the flaps were fully closing wich they were.

Like i said, it only has a hard time starting when its cold. And once it warms up it then kicks in on all 6 cylinders.

If the enrichener was bad wouldn't it affect the motor all the time and not clear itself up once its warmed up??

My serial on my motor is: 5464894

Can anyone shed some light on my previous questions at all??

How about testing the coils and switch box. Can someone tell me what resistances i should be reading everywhere?

Thanks again
Eric
 

sschefer

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Re: 1981 200hp merc, hard time starting, ignition question

what and where should i be looking for on the enrichener? what exactly is its purpose?

I have a brand new battery on it and it seems to be spinning the motor fast enough. As for the choke, it clicks and works, i pulled off the plastic intake casing to make sure al the flaps were fully closing wich they were.

Like i said, it only has a hard time starting when its cold. And once it warms up it then kicks in on all 6 cylinders.

If the enrichener was bad wouldn't it affect the motor all the time and not clear itself up once its warmed up??

My serial on my motor is: 5464894

Can anyone shed some light on my previous questions at all??

How about testing the coils and switch box. Can someone tell me what resistances i should be reading everywhere?

Thanks again
Eric

The enrichner valve is a solenoid valve that works similar to a choke. It is what produces the click when you push in the choke switch. It is sometimes located above and to the side of your top carb. It is usually mounted to the engine block and is not part of the carb except that it may share fuel with it from the main fuel line.

Unless you hold the choke in, it does nothing so it would not effect a running engine that has been warmed up like I think you suspect.

I'm not there to hear and see your engine perform these tricks but I have a feeling that theres nothing wrong in the electronics/coils.

My suspicion is that your carbs could use a rebuild. I think that you are fouling plugs trying to start it and when it finally does, it takes a few minutes for the engine to develop enough heat to burn of the fouling and allow a strong enough spark to occur.

You could try running Sea Foam in the gas at the recommended measures to see if it improves things. Kragens/Oriely's carries SeaFoam in my area not sure where you can buy it, probably any decent auto parts store.

The correct starting procedure when you experience these types of problems was outlined in a previous post. The manual will tell you to make sure the motor is level but sometimes it helps to make sure it is down as far as it can go.
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

i also thought about trying sea foam but I am still trying to wrap my head around the problem being with the carbs. Its like i said. When i put the boat in water and try to start it (after being parked for x amount of days, or even overnight) it has a tremendously hard time starting, to the point that it floods itself and fuel starts coming out of the bottom of the plastic intake box (from fooling around with the throttle and choke so much), then when it finally does start it doesnt run on all 6 cylinders. It has to warm up to kick in.

What i forgot to mention is that it doesn't just all of a sudden "kick in" to all 6 out of no where. It seems to be trying to kick in intermittently before hand, then bingo it stays on all 6. thats why i keep think electrical.

Now back to carbs... Once it would warm up enough to clean off the "foul" It would just do it, wouldnt it? no intermittently cutting in and out, correct? Another thing, if there would be crap in the carbs it normally doesnt get cleared out by warming up the engine, correct? and if it would clear up then it would be always clear from that point, correct?? Say, either the needle and seat, or main jet, or gaskets would need to be rebuilt, that too would not fix itself by heating up the motor, would it?

Awaiting anxiously for your response..

Eric
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

i also thought about trying sea foam but I am still trying to wrap my head around the problem being with the carbs. Its like i said. When i put the boat in water and try to start it (after being parked for x amount of days, or even overnight) it has a tremendously hard time starting, to the point that it floods itself and fuel starts coming out of the bottom of the plastic intake box (from fooling around with the throttle and choke so much), then when it finally does start it doesnt run on all 6 cylinders. It has to warm up to kick in on all 6.

What i forgot to mention is that it doesn't just all of a sudden "kick in" to all 6 out of no where. It seems to be trying to kick in intermittently before hand when cruising around, then bingo it stays on all 6. thats why i keep thinking electrical.

Now back to carbs... Once it would warm up enough to clean off the "foul" It would just do it, wouldnt it? no intermittently cutting in and out, correct? Another thing, if there would be crap in the carbs it normally doesnt get cleared out by warming up the engine, correct? and if it would clear up then it would be always clear from that point, correct?? Say, either the needle and seat, or main jet, or gaskets would need to be rebuilt, that too would not fix itself by heating up the motor, would it?

Awaiting anxiously for your response..

Eric
 

Jeff_G

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Re: 1981 200hp merc, hard time starting, ignition question

Sounds like the stator or switchbox may be bad. Both are subjected to heat related gremlins, both cold and hot. My first inclination would be one of the switchboxes.
The only way to definitively tell whether it is the stator or switchbox is with a peak reading voltmeter. You should have about 180+V from the stator and from the switchbox to the coils.
One easy thing is to crank the engine over with a test light on each spark plug wire in turn and just look for steady firing. That should narrow it down. A spark tester will do the same thing.
I would also check the timing at the same time to ensure it isn't retarded too much.
 

sschefer

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Re: 1981 200hp merc, hard time starting, ignition question

i also thought about trying sea foam but I am still trying to wrap my head around the problem being with the carbs. Its like i said. When i put the boat in water and try to start it (after being parked for x amount of days, or even overnight) it has a tremendously hard time starting, to the point that it floods itself and fuel starts coming out of the bottom of the plastic intake box (from fooling around with the throttle and choke so much), then when it finally does start it doesnt run on all 6 cylinders. It has to warm up to kick in on all 6.

What i forgot to mention is that it doesn't just all of a sudden "kick in" to all 6 out of no where. It seems to be trying to kick in intermittently before hand when cruising around, then bingo it stays on all 6. thats why i keep thinking electrical.

Now back to carbs... Once it would warm up enough to clean off the "foul" It would just do it, wouldnt it? no intermittently cutting in and out, correct? Another thing, if there would be crap in the carbs it normally doesnt get cleared out by warming up the engine, correct? and if it would clear up then it would be always clear from that point, correct?? Say, either the needle and seat, or main jet, or gaskets would need to be rebuilt, that too would not fix itself by heating up the motor, would it?

Awaiting anxiously for your response..

Eric

Up to the point where it starts missing at speed you are describing the classic symptoms of wet fuel fouled plugs. Just out of curiosity, do you have the motor tilted up when it's stored (even overnight).

Also, earlier designs of your engine did not have an enrichening valve of the solenoid type so your's may not.
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

i do keep the motor tilted when stored.. Isn't the enrichener pretty much only for starting the motor? then once the motor is started the carbs get their fuel from the compression of the motor, correct?
 

Jeff_G

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Re: 1981 200hp merc, hard time starting, ignition question

You don't have an enrichner, you have a choke. Unless someone did some changing around later.
 

sschefer

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Re: 1981 200hp merc, hard time starting, ignition question

i do keep the motor tilted when stored.. Isn't the enrichener pretty much only for starting the motor? then once the motor is started the carbs get their fuel from the compression of the motor, correct?
As I noted before, and as Jeff has pointed out, your engine may not have an enrichening valve. There were type I, II and then a change to a sqaure block type fuel pump. If yours is a type I, you should just have a choke plate if it's a type II then you'll have a choke plate with and enrichening valve. It will be about a 3 inch high cylinder shaped object clamped to the block and standing on end. Will with two ports, one out and one in and two wires comming off of it near it's top. The top should have what looks like a stem and if depressed should open the solenoid manually and allow fuel, if the system is primed, to flow into the engine.

Storing the motor in the up position can sometimes cause the symptoms you are describing. Myself and other posters have experienced it. I think my problem was a sticky carb float. I stopped pumping the squeeze bulb when the motor was tilted up and instead waited until the motor was down and it started fine. That gave me the clue that was missing for my solution. I rebuilt my carbs and the problem has never returned either tilted up or down. I do not know for sure if that is the cure for you but you can try avoiding pumping the primer bulb until after the motor is down and see what effect, if any it has.
 
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workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

ok, so now that we know my motor does not have the enrichener ( i will double check to be certain), where does that leave me? do my carbs need a simple rebuild you think? I am still confused by how the carbs could "clear" themselves out when the motor heats up and then go back to being bad when cold...carbs dont usually do that do they? or, is it just as simple as the cylinders being overfueled and fouling when trying to start it when cold, caused by bad carbs (needing rebuild)??

Thanks so much to you all
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

ok, just went outside and checked to see if i have the enrichener or not. I believe i DONT have it. there is only the main fuel line going in the fuel pump and 1 coming out of it and teeing off directly to the carbs.....
 

sschefer

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Re: 1981 200hp merc, hard time starting, ignition question

ok, so now that we know my motor does not have the enrichener ( i will double check to be certain), where does that leave me? do my carbs need a simple rebuild you think? I am still confused by how the carbs could "clear" themselves out when the motor heats up and then go back to being bad when cold...carbs dont usually do that do they? or, is it just as simple as the cylinders being overfueled and fouling when trying to start it when cold, caused by bad carbs (needing rebuild)??

Thanks so much to you all
I know that it's less expensive (about 15.00 each) to rebuild the carbs then it is to start chasing electrical problems. I think your synopsis is pretty much correct. It should take you about a day to pull them off, clean them, set the floats and put them back together. Change the float needles and seats even if they look o.k. If the problem goes away, you're done. If it doesn't then at least you can eliminate them and concentrate on the next level. One of the tricks in trouble shooting these things is to pick a path and follow it to the end. Don't jump around, it's easy to confuse results.
 

workaholic

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Re: 1981 200hp merc, hard time starting, ignition question

i have been looking around on eBay (we dont have the best marine shops around here) for the proper carburetor rebuild kits for my model but they seem to be fairly pricy (almost 100$ each) The 15.00$ kits your mentioning do those include the needle and jet, floats, ect ect? or just the gasket set?

I did find this kit on ebay for 39.95$, but I am not sure if its the correct kit for my model, its item #250475455671.

Does it look like the correct kit?

Thanks
Eric
 

sschefer

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Re: 1981 200hp merc, hard time starting, ignition question

Have you looked here on iBoats in Boat Motor Parts?
 

j_martin

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Re: 1981 200hp merc, hard time starting, ignition question

The most likely part to fail in an 81 V6 is the foam floats in the carburetors. The 5 dollar kits have all the gaskets and seal that will fail. Needles and seats seldom fail and can be had for about 15 bucks a set for each (2 per carb). The floats, however, are NLA, and not made by any aftermarket supplier. The best bet in that case is to score a set of carbs off'n eBay during the winter. All the WH floats will interchange. The hard plastic ones last forever. The gaskets loose their goody after awhile, and will fail if you try to reuse them. If normal pressure on the primer bulb doesn't flood the carbs, the needles are good. A white knuckle squeeze will normally overcome the needle valves. (7 lbs max rating, it's easy to get 10 - 12)

That said, maybe you're chasing your tail. If the starter is drawing too much current, and has a drag to it, it will fail to spin the engine fast enough for a strong spark, and tend to drop out if 1 cylinder hits, killing the start cycle. It's a pernicious thing, sneaking up on you over time.

I just went through that. I was getting to the point of thinking the old girl would need a "freshening up" which is Greek for dumping a bunch of money and time into it. Then the starter failed, and it seemed just like a bad battery, so I spent 80 bucks for a 40 dollar battery at a marina, probably trading in a used Wal-Mart battery that was better than the one I got. When I fixed the starter, the engine seemed to gain a new attitude, mostly because it starts quickly without loading up.

The easiest way to see if this might be the case is to get a magnetic current tester (19 bucks at NAPA, among others) and check your starting current. It should be around 125 amps cranking, with a quick spike when it first hits.

hope it helps
John
 
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