2018 Mercury 60HP ELPT Four Stroke Bogging

[burns.316]

So, my Mercury four stroke is bogging. I have a fair amount of experience with 4 stroke engines, but not outboards; so I never know if a problem is related to the lower/cooing system.

Engine starts fine, idles fine. Boat doesn't seem to idle as fast as it used to (2.5mph vs maybe 3.5mph before?). I can push the motor up maybe 60-70% of the way by RPM (don't have a tachometer) and then it does a ren-ren-ren-ren like it's starving for fuel, but has never stalled. Doesn't seem speed related, more RPM/time related. If I go to WOT, it seems fine for 2-3s, then it bogs down.

I figured it was bad gas; filled up with no ethanol 89 Oct from the busy station by my house (way away from the water). Put an ounce of Mercury's fuel treatment in the 10gallon tank, replaced the bowl filter (it as very mildly dirty) and inline (can't see what's in that one). It was time to change the oil and filter anyhow, so I did that as well. Same problem, doesn't seem resolved or improved at all.

Noticed I have this on my boat - I don't know exactly what it is, and can't find it online. I assume it's a fuel filter or water separator, but I don't know to replace it, drain it, put something different, remove, what?

If someone could spell this guy out for me, that would be great.

Also, with the metered air on this, is there an air filter I should check/clean/replace? My manual doesn't mention one. If I have replaced these two filters, and do whatever I need with this guy on the boat, where should I look next? Fuel injectors? Spark plugs?

I'm kind of at a loss, the motor is a 2018, has only a hundred or so hours on it.

Thanks for the helps.

 

[frustratedboater]

So, my Mercury four stroke is bogging. I have a fair amount of experience with 4 stroke engines, but not outboards; so I never know if a problem is related to the lower/cooing system.

Engine starts fine, idles fine. Boat doesn't seem to idle as fast as it used to (2.5mph vs maybe 3.5mph before?). I can push the motor up maybe 60-70% of the way by RPM (don't have a tachometer) and then it does a ren-ren-ren-ren like it's starving for fuel, but has never stalled. Doesn't seem speed related, more RPM/time related. If I go to WOT, it seems fine for 2-3s, then it bogs down.

I figured it was bad gas; filled up with no ethanol 89 Oct from the busy station by my house (way away from the water). Put an ounce of Mercury's fuel treatment in the 10gallon tank, replaced the bowl filter (it as very mildly dirty) and inline (can't see what's in that one). It was time to change the oil and filter anyhow, so I did that as well. Same problem, doesn't seem resolved or improved at all.

Noticed I have this on my boat - I don't know exactly what it is, and can't find it online. I assume it's a fuel filter or water separator, but I don't know to replace it, drain it, put something different, remove, what? View attachment 345106

If someone could spell this guy out for me, that would be great.

Also, with the metered air on this, is there an air filter I should check/clean/replace? My manual doesn't mention one. If I have replaced these two filters, and do whatever I need with this guy on the boat, where should I look next? Fuel injectors? Spark plugs?

I'm kind of at a loss, the motor is a 2018, has only a hundred or so hours on it.

Thanks for the helps.

First off, No Air filter
You're mentioning a lot of different systems and for sure it could provide similar results that you are experiencing form any of them. Given that your engine has so little hours, I would bet that it is fuel related, but if your fuel/water was full and sucked in some H2O, than you'd be looking towards the carb. And 4-stroke carbs has lots of water hiding places!! There should be a small brass-looking drain screw at the bottom of each of the fuel bowls and with a shop rag underneath, unscrew that about 1 to 1-1/2 turns out and let drain. I'd be great if you could collect what's draining out, but the designers thought not to provide that space :-(
Next, unscrew that separator filter and dump into a glass jar to see if there is any visible H20..
Let us know..

 

[burns.316]

First off, No Air filter
You're mentioning a lot of different systems and for sure it could provide similar results that you are experiencing form any of them. Given that your engine has so little hours, I would bet that it is fuel related, but if your fuel/water was full and sucked in some H2O, than you'd be looking towards the carb. And 4-stroke carbs has lots of water hiding places!! There should be a small brass-looking drain screw at the bottom of each of the fuel bowls and with a shop rag underneath, unscrew that about 1 to 1-1/2 turns out and let drain. I'd be great if you could collect what's draining out, but the designers thought not to provide that space :-(
Next, unscrew that separator filter and dump into a glass jar to see if there is any visible H20..
Let us know..

I have fuel injectors, no carb.

Is this picture a fuel/water separator? I thought that's what it was, but there doesn't appear to be any sort of stop **** or anything on it. There's a slot in the bottom maybe for a screw driver, but I think if I put one in there and turned, it would break. It looks like through the slot is maybe a diaphragm, but maybe it's a pin valve? This is on the boat (2017 Grizzly Tracker).

Not to confuse the subject, but was reading this could be my FSM as well...

 

[frustratedboater]

I started typing VST, then changed to carb, that's what happens when one assumes.. So, on your "VST", there is a small brass drain screw... follow the same procedure as above post... Collect as much fuel in a can or jar so you can see if there is any junk/H2O that comes out..
As far as the picture that you posted, the separator looks like an oil filter on a car that is mounted between the fuel tank and you hose leading to your outboard. There may be a chance that there is not one set up in your boat also.
It could be a number of things, clogged injector screens, in-line filter, etc. If it can't be discovered you may have to take it to your local marine repair shop and make an appointment. If you're familiar with 4-stroke outboards than we can steer you in the right direction. Shop manuals for your engine have troubleshooting guides to follow. iBoats is a great source!

 

[burns.316]

I started typing VST, then changed to carb, that's what happens when one assumes.. So, on your "VST", there is a small brass drain screw... follow the same procedure as above post... Collect as much fuel in a can or jar so you can see if there is any junk/H2O that comes out..
As far as the picture that you posted, the separator looks like an oil filter on a car that is mounted between the fuel tank and you hose leading to your outboard. There may be a chance that there is not one set up in your boat also.
It could be a number of things, clogged injector screens, in-line filter, etc. If it can't be discovered you may have to take it to your local marine repair shop and make an appointment. If you're familiar with 4-stroke outboards than we can steer you in the right direction. Shop manuals for your engine have troubleshooting guides to follow. iBoats is a great source!

I put a baggie under the VST and opened the screw. I collected about 3 oz of pure clean gasoline.

I happened to open the thermostat (which I clogged up recently) and found a little sand in there, but it rinsed right out - it wasn't gummed up or anything.

I'm running the motor on the garden hose now (to flush the coolant system).

I don't find a water separator on my boat.

Other ideas?

One question I do have, if the computer is keeping me from hitting top RPM (if the telltale is getting too hot or something) should my alarm sound? It doesn't, but I don't know if it's just limiting the RPMs if I would expect the alarm or not.

 

[fishingfever55]

I put a baggie under the VST and opened the screw. I collected about 3 oz of pure clean gasoline.

I happened to open the thermostat (which I clogged up recently) and found a little sand in there, but it rinsed right out - it wasn't gummed up or anything.

I'm running the motor on the garden hose now (to flush the coolant system).

I don't find a water separator on my boat.

Other ideas?

One question I do have, if the computer is keeping me from hitting top RPM (if the telltale is getting too hot or something) should my alarm sound? It doesn't, but I don't know if it's just limiting the RPMs if I would expect the alarm or not.

Did you ever find out your problem? I have a 115 doing the same thing