Tracker Pro Series 60hp help, please.

[AmericanHoney]

I have been having some issues with my Tracker Pro Series 60hp (by Mercury) and was hoping somebody help diagnose what may be the cause. I will try my best to explain what I am experiencing but please excuse my inexperience in dealing with an outboard engine.

I have had the boat for a few years now (Nitro 640lx) but starting last year I noticed a few issues popping up. The main one is the difficulty I have in getting on plane, especially with a second person onboard, that i didn't experience when I first had the boat. When I go WOT the rpms come right up to about 3200 and then are stuck there 20-30 secs until they slowing creep up to about 4000 rpms, at which point the boat comes up on plane and then rpms quickly climb to the max of about 5500. Sometimes it takes the second person moving into the bow of the boat to get it to plane. It still struggles in a similar fashion when I am alone but almost all the time it gets on plane without me attempting to move forward. Once I am up on plane the boat reaches the max speed it has always reached for me, about 32-35 mph.

Last year when this issue sprung up I replace the spark plugs and that seemed to help, but did not eliminate the issue. I also bought a new prop, just a replacement of the original prop that was a bit dinged up and that didn't change a thing.

The second and possibly related issue, sprung up at the end of last year. I often throttled up to power load when putting the boat on the trailer without issue. But now when I attempt to throttle up to push the boat up to the bow roller the engine just bogs down and quits almost immediately.

The only other thing I noticed that may be a clue is that when I have the throttle on idle the motor will often quit if I leave it there for more than about 10 secs. If I throttle up just a little bit it can stay there without any quitting.

Any help anybody could offer in diagnosing/fixing these issues would be greatly appreciated. It doesn't prevent me from using my boat and most times it seems to be running just fine. It's just something seems off, that didn't always feel that way. Thank you.

 

[gm280]

Sounds like it is time to do a compression test AND clean the carbs if they have never been cleaned before. I would also check the fuel pump as well. Could be a lot of little things that need cleaned and serviced. But I would start with the compression first to verify you have good compression across all cylinders for starters. Since you didn't specify the year and engine model number, and serial number, that is about it. JMHO

 

[JDusza]

Yes. Test compression just to get it off the list. Look for all cylinders to be within 10% of each other. You can also check your spark with an air gap spark tester. Look for the spark to jump 3/8" or 7/16". That takes ignition off the list.
You're looking at poor fuel delivery.Get compression and spark off the list and have a go at your carburetor.
J

 

[Canufixit2]

Did you change the prop pitch or diameter / same prop?

Did you change the tilt setting of the engine. Do you have power tilt?? did anyone change the max down setting bar???

I'd try some Merc fuel treatment as well ....

 

[AmericanHoney]

Thanks guys I will look into all the things you mentioned. The new prop is the same as the previous one, the problem started when I still had the old prop, tried a new prop to see if it would make a difference.

Power tilt and nothing was changed with it.

I have one other question. I took the engine cover off, to start figuring out what I need to do for the recommendations given, and while it was off I pumped the primer bulb. Once the primer bulb got hard, I was looking around again and noticed a good bit of gas mixture leaking out of somewhere in the carburetor area. If I had to guess I would say it was the bottom carb. (there in a vertical row). Could this be a symptom that might lead to the problem I am having? I will go through the recommended items, will take me a while since I have to learn how to do each one. Just thought this new info might be relevant.

Thanks again.

The engine is a 2004, not sure of model #, the serial # is 1B048511

 

[gm280]

AH, Yes that would certainly contribute to your problems. Sounds like it is time to install some carb kits now as well, after there are thoroughly cleaned of course. JMHO

 

[Silvertip]

Fuel leaking from the carb(s) while squeezing the primer bulb indicates the inlet needle is allowing excess fuel into the carb. During operation, especially at idle, the engine may by running rich which is why it loads up and dies. That same overly rich mixture is why the boat doesn't come on-plane. The engine cannot effectively burn that excess fuel at low rpm so it the reason you experience the bog until it gets higher up in the rpm band. As indicated, start with a compression check but I suspect that's ok and a good carb cleaning, installation of the kits, properly setting float level and drop and then proper mixture adjustment should take care of the problem.

 

[AmericanHoney]

Thanks guys! I will order the carb kits tonight. Let you know how I make out.

 

[AmericanHoney]

I went through and cleaned the carbs, they were actually very clean to start, replaced all the needles and set the float heights. But even after taking the bottom carb apart again, confirming there is nothing in the needle valve seat and that the float height is correct it still leaks fuel. The top two have no issue. I can't figure out what is different with the bottom one. I don't see how to replace the seat, so am I better off buying a whole new carb assembly.

The fuel doesn't come gushing out of the overflow tube, but once the primer bulb is hard it starts slowly leaking out then stops until I squeeze the primer bulb again. I want to say it is about a teaspoon of gas that comes out each time before it slows to a stop.

I don't see how to replace the seat, so am I better off buying a whole new carb assembly. I don't see what else could be wrong???

 

[wn6ngp]

It seems unlikely that the seat is worn out. I'm thinking that something is keeping that float needle from traveling up to shut off fuel flow. I know that you've checked this but I'd check again to make sure that the needle does rise up and block off that fuel inlet when its pumped up fully. Maybe the float in the bowl has a hole in it and is filling with fuel, that would cause it to be slowing sinking down causing the needle to fall back in turn letting excess fuel to come back in,

Can you work on the carb on a work bench and pump fuel into so you can more closely observe what is going on?

 

[gm280]

AH, some times the seat can't be replaced. But you can take some cotton swabs and use them to thoroughly clean the seat. I even used a half cotton swab and installed it in a Dremel tool and used some Brasso polish to clean the seats in carbs before. And that did work very well. It takes a few cotton swabs, but persistence does buy off. Just cut them in half and use a drill or Dremel type tool to spin them up. The Brasso cleans the brass seats like mirrors too.

If the needle and seat are doing their job, you shouldn't be able to force gas pass it with the primer bulb. That is how you know you still have a problem with that carb. JMHO