1991 Four Winns 170 Freedom 3.0HO GM Straight 4 with Cobra Stern I/O

[ConnieMarie]

I'm having trouble starting my engine, I typically run the boat once a week. Beginning of season she was firing right up, each week it has become harder and harder to start. Now the engine will not start. It sounds likes its turning over and occasionally it will start run rough for a couple minutes and stall. Last week it ran rough until it warmed up awhile then would start every time. This past weekend wouldn’t even start.
The battery is brand new and holds charger about 12.5 volts. The spark plugs are brand-new Tr5 NGK, however I did not gap these, was under the impression they came pre gapped. New plug wires replaced as well. I can visually see gas dripping into top of carb, I've been taking the filter off to allow more air to get into the system at start up. When replacing the plugs today they had what appeared to smell and look like gas on them. I've done some research and ordered a "ignition tune up" kit which includes distributor cap, rotor, condenser and contact points. I have checked all the fuses all seem to be in good shape.
Unfortunately, the boat is already in the water and about a 30 minute drive from home. I intend on bringing up my multi meter to hopefully further diagnosis the issue. The previous owner replaced the distributer cap and some point. I have not taken it off so I have no idea what’s going on underneath. I’m hoping I can replace points and condenser without having to adjust the timing, from what I’ve read this will not be possible. Any input would be much appreciated. I’m a first time boat owner and somewhat mechanically inclined. I don't have a tachometer or timing light hopefully I can find some cheap ones somewhere?

 

[bruceb58]

You don't have points on a 91 engine. Even if it was a 90 you wouldn't have points. What is your model number?

I also don't think the spark plugs you have are correct. You have a long reach plug in there and you should have the short reach. I believe you should be using MR43T and you are using the NGK equivalent of a MR43LTS. Double check on this. Does your motor have a sticker that specifies the spark plug?

 

[ConnieMarie]

My model number is 302CPRPWS. I dont see a sticker for plugs. I replaced the plugs with exact same plugs which were already in there when it ran fine.

 

[ConnieMarie]

My model number is 302CPRPWS. I dont see a sticker for plugs. I replaced the plugs with exact same plugs which were already in there when it ran fine. I should probably cancel my order then

 

[ConnieMarie]

I should clarify it comes with a "contact set" not points.

 

[ConnieMarie]

I should clarify it comes with a "contact set" not points.

 

[ConnieMarie]

I should clarify it comes with a "contact set" not points.

 

[bruceb58]

I should clarify it comes with a "contact set" not points.

A contact set is another name for points. Don't you have an EST distributor on there?

Just so you know, you have a 1990 drive in case you need to get parts.

This is what the 1990 manual shows for plugs. The AC-R43TS crosses to a NGK UR5. It is a different reach than the TR5. I think you have the wrong plug. That may explain things a bit.

 

[ConnieMarie]

Okay I do have EST system after further reading. I'll try swapping for UR5, my concern is that the TR5 were already in there when it ran fine. I noticed while reading there is a knock sensor for low range 86 octane and one for high range 89 octane. I put 89 in ti help dilute old gas could this be why it wont start?

 

[bruceb58]

I really doubt you have a knock sensor. Different octane fuel won't make a difference.

How old was your fuel that was in there?

Where did you read that it had a knock sensor?

 

[ConnieMarie]

I read about it in the ignition system section of the Seloc manual. I didn't think it would be an issue until I read that but doubt it at this point. Fuel was from last season with stabilizer added. Now its a full tank fresh 89. Where should I begin troubleshoot if these new plugs aren't issue? Im leaning toward the distributer cap.

 

[bruceb58]

Throw away your Seloc manual and get the OEM. I sent you a PM with a link to one. did you get it?

 

[ConnieMarie]

I did not get the link but have downloaded one already.

 

[ConnieMarie]

I apologize I found it in my inbox thank you sir!

 

[bruceb58]

If/when you go to check your timing, read the instructions carefully on how to put the EST distributor into base mode. You likely don't need to touch it unless someone before you(same person who put in the wrong plugs) touched it.

 

[MikDee]

I hope the long spark plugs are not hitting the pistons, or valves?

 

[ConnieMarie]

The previous owner did not mess with timing. I not going to lie but i'm nervous when it comes to messing with timing plus I do not have a timing light. I'll start by swapping the plugs. Based on that handy manual you supplied, I will then test solenoid, ignition switch and safety switch with my multimeter. After that I'll attack distributer cap. Maybe when I unhooked the battery I put the cables back incorrectly. I have what appears to be an after market fuse type wire followed by a secondary wire and main wire for both negative and positive sides.

 

[bruceb58]

If the engine is cranking(starter motor spinning engine) then you don't need to worry.

If it's rotating slow, your battery needs to be load tested and/or you need to clean up all your battery cable connections both at the battery itself and the starter and engine block.

 

[ConnieMarie]

Oh yeah its cranking fine. I had the battery tested its only about a year old and tested perfect. I sanded down all the terminals/connections they weren't terrible. This is why I believe its a spark issue because the motor cranks fine and sounds like it wants to start but doesn't. I just am not sold on it being the wrong plugs because the engine ran fine several times with those plugs, but its a starting point.

 

[Maclin]

Some of the symptoms and description sound like the carb may be leaking raw fuel into the intake and flooding it somewhat. When it becomes hard to start move the throttel to near wide open (in throttle only mode!) and crank it, be ready to move the throttle back when it catches. If this procedure works then the carb may be draining into the intake and thus engine is flooding in between uses and the carb may need to be rebuilt.