2003 Mercury 200 2 Stroke carb running hot at idle. New impeller, new thermostats

[diver94]

Hi,

I have a problem with my 2003 Mercury 200 2 Stroke (Carbureted). The engine runs hot (not hot enough to trigger the alarm). It runs at aprox 164 degrees (I use an infrared thermometer).

Also, when I run it on the muffs, it takes almost 3 minutes for the engine to start peeing and the water comes out hot (155 degrees) … I know the thermostats open at 143. I recently installed the new thermostats, but that didn’t make a difference.

The telltale stream is weak and hot, but the lower telltale is very strong (see pics)

The same happens when I connect the hose to the flush fitting (running water through the cooling system without the engine running). Very weak stream from the actual telltale (and it takes it a longggg time to start peeing) and a strong stream form the lower unit telltale.

The former owner had the impeller replaced recently. I ran some barnacle buster to clean the passages, but it didn't make a difference.

Again, the water flow coming from the lower unit telltale is very strong (see picture). However, the normal telltale has a weak (weaker) stream.

Is it possible that when the impeller was replaced, they didn’t line up the tube properly?

By the way, I didn’t know that 2 stroke Mercs pee from the lower unit area too.



Thanks!

Lou

 

[Faztbullet]

Every thing you describe is normal with a 2.5 motor, it will not pee until t-stats open and pee will be hot.

 

[diver94]

Every thing you describe is normal with a 2.5 motor, it will not pee until t-stats open and pee will be hot.

Hi and Thanks! I think thats a little too hot. I dont the engine should be running at 163 degrees (water comes out at 156 degrees..you can see smoke coming out with the water). You can’t touch it.
Also, when the water hose is connected to the flushing port, it barely pees from the telltale. Sometimes it doesn’t pee at all. But I see a lot of water (good pressure) coming out the lower telltale fitting or hole.

By the way, what is that fitting or hose down there in the lower unit? Is it part of the water cooling system? I don’t remember other engines peeing so strong from there.
Thanks!

 

[Chris1956]

The gratings above the antiventilation plate are normal cooling water exits. Only some of the cooling water and exhaust come thru the prop.

So you believe the former owner had the impeller replaced? That is a large leap of faith. Do you have any receipts to show date of service?

 

[diver94]

Hi and Thanks! I think thats a little too hot. I dont the engine should be running at 163 degrees (water comes out at 156 degrees..you can see smoke coming out with the water). You can’t touch it.
Also, when the water hose is connected to the flushing port, it barely pees from the telltale. Sometimes it doesn’t pee at all. But I see a lot of water (good pressure) coming out the lower telltale fitting or hole.

By the way, what is that fitting or hose down there in the lower unit? Is it part of the water cooling system? I don’t remember other engines peeing so strong from there.
Thanks!

The gratings above the antiventilation plate are normal cooling water exits. Only some of the cooling water and exhaust come thru the prop.

So you believe the former owner had the impeller replaced? That is a large leap of faith. Do you have any receipts to show date of service?

No receipts. But the pressure that comes out of that lower unit telltale is pretty strong.
Also, the guy was pretty straightforward on all the info he gave me. Just in case, I will have the impeller changed.
Thanks,
Lou

 

[Dukedog]

No receipts. But the pressure that comes out of that lower unit telltale is pretty strong.
Also, the guy was pretty straightforward on all the info he gave me. Just in case, I will have the impeller changed.
Thanks,
Lou

ya might wanna consider a water pressure gauge...........

does tha lower have "slots" or an anode?

 

[flyingscott]

Hi and Thanks! I think thats a little too hot. I dont the engine should be running at 163 degrees (water comes out at 156 degrees..you can see smoke coming out with the water). You can’t touch it.
Also, when the water hose is connected to the flushing port, it barely pees from the telltale. Sometimes it doesn’t pee at all. But I see a lot of water (good pressure) coming out the lower telltale fitting or hole.

By the way, what is that fitting or hose down there in the lower unit? Is it part of the water cooling system? I don’t remember other engines peeing so strong from there.
Thanks!

Why not? The thermostat only opens at 143 deg not abnormal for a motor to run hotter than that.

 

[diver94]

The gratings above the antiventilation plate are normal cooling water exits. Only some of the cooling water and exhaust come thru the prop.

So you believe the former owner had the impeller replaced? That is a large leap of faith. Do you have any receipts to show date of service?

Please check out the strong stream coming of the lower unit pee hole. Have you seen that before?

 

[diver94]

Why not? The thermostat only opens at 143 deg not abnormal for a motor to run hotter than that.

I've had outboard engines for over 15 years. I have never seen of heard of scolding water (156 degrees...and you can see a little steaming or smoke) coming out of the telltale. I had several Optis 150s and 200s, Yamaha OX66s and Johnson/Evinrude 2 stroke engines.

 

[Dukedog]

Please check out the strong stream coming of the lower unit pee hole. Have you seen that before?

THATS very normal.. not really a "pee hole".. jus water/exhaust discharge... ya didn't say if ya have slots or an anode.. if it isn't alarmin' (beepin') send it..

oh yeah, ya should have a butt load comin' outta tha prop hub also............

 

[flyingscott]

I've had outboard engines for over 15 years. I have never seen of heard of scolding water (156 degrees...and you can see a little steaming or smoke) coming out of the telltale. I had several Optis 150s and 200s, Yamaha OX66s and Johnson/Evinrude 2 stroke engines.

That motor has the tell tale connected directly to the thermostat. pretty specific to the 2.5 merc motors also done on the smaller 25 hp motors. I think you are looking for problems that are not there.

 

[Dukedog]

ya didn't say if ya gettin' those temp readings when on tha hose and/or runnin' down tha lake???

 

[diver94]

THATS very normal.. not really a "pee hole".. jus water/exhaust discharge... ya didn't say if ya have slots or an anode.. if it isn't alarmin' (beepin') send it..

oh yeah, ya should have a butt load comin' outta tha prop hub also............

ya didn't say if ya gettin' those temp readings when on tha hose and/or runnin' down tha lake???

I tried the earmuffs first and then I put the lower unit completely immersed in a 100 Gals Rubbermaid tank...same results.

Im not sure whet you mean by "slots or anodes". The engine have anode zincs, but that's not related to the water temp.
No, the engine is not beeping

 

[diver94]

ya might wanna consider a water pressure gauge...........

does tha lower have "slots" or an anode?

That's a good idea (water pressure gauge)

 

[Dukedog]

get a pressure gauge then ya need ta run it like ya stole it at tha lake.. if it "alarms" fix it, if doesn't ya good..... askin' bout slots or anodes.. where ya say tha "pee hole" is at in tha side of tha gear case.. it should be an anode there on both sides.. if it has exhaust "slots" instead tha gear case has been changed...

 

[diver94]

THATS very normal.. not really a "pee hole".. jus water/exhaust discharge... ya didn't say if ya have slots or an anode.. if it isn't alarmin' (beepin') send it..

oh yeah, ya should have a butt load comin' outta tha prop hub also............

What I meant to say was "is it normal that while using the hose to flush the engine (not running/just flushing water though the cooling system) for the telltale to barely spit water while a strong stream comes out of the water/exhaust exchange discharge hole? And it takes almost 3 minutes for the telltale to start peeing (again, this is with the water hose connected to the flushing port/not running). Could it be a small obstruction or rust in the exhaust system or in one of the hoses?

 

[diver94]

THATS very normal.. not really a "pee hole".. jus water/exhaust discharge... ya didn't say if ya have slots or an anode.. if it isn't alarmin' (beepin') send it..

oh yeah, ya should have a butt load comin' outta tha prop hub also............

Please check out the picture. Its strong stream of water coming from the top (not coming from the sides). On the sides I have anodes

 

[Dukedog]

"What I meant to say was "is it normal that while using the hose to flush the engine (not running/just flushing water though the cooling system) for the telltale to barely spit water while a strong stream comes out of the water/exhaust exchange discharge hole?"

yes.. tha T stats are closed so only a trickle will pas by 'em while tha rest will go out tha housing/prop

can't tell anything (where its comin' from) in that picture

take a picture of tha side of tha gearcase with it runin' with MUFFS only...

 

[Dukedog]

if i'm seein' what i think i'm seein' its not supposed ta be any discharge there.....

 

[diver94]

"What I meant to say was "is it normal that while using the hose to flush the engine (not running/just flushing water though the cooling system) for the telltale to barely spit water while a strong stream comes out of the water/exhaust exchange discharge hole?"

yes.. tha T stats are closed so only a trickle will pas by 'em while tha rest will go out tha housing/prop

can't tell anything (where its comin' from) in that picture

take a picture of tha side of tha gearcase with it runin' with MUFFS only...

Will do. Thanks!