Im a boat mechanic up in kentucky, and I found this very helpful. Had a customer with a very similar motor of yours. Good to know that these specific merc series experience hot idle
@@sethgabbard7705 he wants the lower unit serviced including a pressure tested, new water pump, spark plugs and maybe a carb clean. So yea just about everything. I’ll throw in a compression and spark test too.
That looks way better than previous video. I'd bet you flushed out a good piece of old impeller with the garden hose. Its a little strange that stream heats up more at idle but important thing is that block isn't getting too hot.
If the telltale is coming from the thermostats it will be as hot as the thermostat opening temperature. Most thermostats are above 130F. Its important to get the motor to operating temperature. You can check the idle temp by using an IR thermometer at the venter of ther thermostat housing.
greauxpete … I completely agree with you about the water temp being up to 130^F coming from the telltale but this particular motor was basically boiling well above 130^F. In part 6 I show the reason. The owner finally confessed that he ran the motor full throttle back to the dock with the over temp alarm going off. The water pump housing was completely melted and the impeller fins were broken off and lodged inside the power-head. Part 6 reveals the damage to the pistons and rings and I believe this is why the telltale was so hot because the damage causes more friction and higher operating temps. It was just a matter of time before this engine would fail. Thanks for watching and commenting.
Oh I see now that this is a series of videos So disregard my previous video comment / Question- Not much experience w/ Mercury motors mainly owned OMC all my life but traded for on of this motors & it has some cooling issues - Previous owner said when first cranked it pee water fine but after couple hundred yard stops or intermittent till alarm goes off being hot- Mec replaced pu m p impeller & still ran hot - Mechanic removed exhaust plate housing but couldn't see any obstruction- This motor has jet pump instead of gear case So I'm wondering if it was idle close to bottom sand Maybe clogged w/ sand mud? Oh well fellow didn't want to spend any additional ones trying to figure out So I'm swapping some parts for the motor- I haven't picked it ip yet though but noticed from some other vids It doesn't appear to have thermostats on these older 4 cyl. Motors or am I missing them?
@@LivetofishOutboardRepair is there a pop it valve instead? I have this same motor and I’ve tried just about everything to get it to pee but it just comes out exhaust any advice? I ran water through top end with lower unit off like the beginning of video and water came out steady but when I got the lower unit back on it still wouldn’t pee.
@jayy8472 you might want to try to remove the water cover plate and examine the passages to see if old water pump impeller pieces are stuck in there, blocking the flow of water as shown in part six ua-cam.com/video/OnWXUnvqJt4/v-deo.htmlsi=91cquiDz8sxvN2E4 if I recall correctly, this model does not have a poppet valve or thermostat.
@@jonathanaguilar9452 I don’t believe it’s overheating. These models do not have a thermostat so by the time the water reaches the top of the motor and exists the telltale it can be pretty warm. 145 - 200 is probably acceptable. In my video the high temperature alarm went off so I know it was overheating but it was hotter than 200 *F when the alarm triggered. If the head is too hot to touch then it’s to hot.
Jonathan Aguilar … The motor I was working on was boiling at neutral and dropped to over 150*F after removing all the impeller pieces stuck in the block. If you watch part 6 you’ll see the reason. ua-cam.com/video/OnWXUnvqJt4/v-deo.html IMO 200 degrees in neutral is probably ok as long as the pee stream cools at higher rpm’s.
Im a boat mechanic up in kentucky, and I found this very helpful. Had a customer with a very similar motor of yours. Good to know that these specific merc series experience hot idle
If you watch part six you'll see why it idled hot. I don't believe this is normal.
Glad you had that issue finally fixed! That 25 looks to be in great shape. Keep the videos coming
Yea me too. The 25 looks almost brand new. I think it has never been taken apart for Service. Everything looks untouched.
@@LivetofishOutboardRepair can’t wait for that! Is it getting a full service?
@@sethgabbard7705 he wants the lower unit serviced including a pressure tested, new water pump, spark plugs and maybe a carb clean. So yea just about everything. I’ll throw in a compression and spark test too.
@@LivetofishOutboardRepair looks like I need to come over to you lol. I gotta ton of projects on hand right now.
That looks way better than previous video. I'd bet you flushed out a good piece of old impeller with the garden hose. Its a little strange that stream heats up more at idle but important thing is that block isn't getting too hot.
My thoughts exactly. I think now if I replaced the water pump housing it might just pump more efficiently and it would be lukewarm. Just my opinion.
How do you change water pump in a classic 50 1987
If the telltale is coming from the thermostats it will be as hot as the thermostat opening temperature. Most thermostats are above 130F. Its important to get the motor to operating temperature. You can check the idle temp by using an IR thermometer at the venter of ther thermostat housing.
greauxpete … I completely agree with you about the water temp being up to 130^F coming from the telltale but this particular motor was basically boiling well above 130^F. In part 6 I show the reason. The owner finally confessed that he ran the motor full throttle back to the dock with the over temp alarm going off. The water pump housing was completely melted and the impeller fins were broken off and lodged inside the power-head. Part 6 reveals the damage to the pistons and rings and I believe this is why the telltale was so hot because the damage causes more friction and higher operating temps. It was just a matter of time before this engine would fail. Thanks for watching and commenting.
Oh I see now that this is a series of videos So disregard my previous video comment / Question- Not much experience w/ Mercury motors mainly owned OMC all my life but traded for on of this motors & it has some cooling issues - Previous owner said when first cranked it pee water fine but after couple hundred yard stops or intermittent till alarm goes off being hot- Mec replaced pu m p impeller & still ran hot - Mechanic removed exhaust plate housing but couldn't see any obstruction- This motor has jet pump instead of gear case So I'm wondering if it was idle close to bottom sand Maybe clogged w/ sand mud? Oh well fellow didn't want to spend any additional ones trying to figure out So I'm swapping some parts for the motor- I haven't picked it ip yet though but noticed from some other vids It doesn't appear to have thermostats on these older 4 cyl. Motors or am I missing them?
Katie Lowe …. No T stat on this motor.
@@LivetofishOutboardRepair is there a pop it valve instead? I have this same motor and I’ve tried just about everything to get it to pee but it just comes out exhaust any advice? I ran water through top end with lower unit off like the beginning of video and water came out steady but when I got the lower unit back on it still wouldn’t pee.
@jayy8472 you might want to try to remove the water cover plate and examine the passages to see if old water pump impeller pieces are stuck in there, blocking the flow of water as shown in part six ua-cam.com/video/OnWXUnvqJt4/v-deo.htmlsi=91cquiDz8sxvN2E4 if I recall correctly, this model does not have a poppet valve or thermostat.
i have a 1988 sea ray outboard in neutral it also comes out very hot and when i accelerate it gets cold????
Jonathon Aguilar … That’s sounds right.
@@LivetofishOutboardRepair is not overheat
@@jonathanaguilar9452 I don’t believe it’s overheating. These models do not have a thermostat so by the time the water reaches the top of the motor and exists the telltale it can be pretty warm. 145 - 200 is probably acceptable. In my video the high temperature alarm went off so I know it was overheating but it was hotter than 200 *F when the alarm triggered. If the head is too hot to touch then it’s to hot.
you know what temperature it has to be in the Needle it goes up from 145 to 200 in neutral and when accelerating it goes down to 145
Jonathan Aguilar … The motor I was working on was boiling at neutral and dropped to over 150*F after removing all the impeller pieces stuck in the block. If you watch part 6 you’ll see the reason. ua-cam.com/video/OnWXUnvqJt4/v-deo.html
IMO 200 degrees in neutral is probably ok as long as the pee stream cools at higher rpm’s.
I have a 1986 50 classic I can't find the thermostat
This vintage does not have a thermostat
That's not normal
Your so right! See part six to find out why backflushing didn’t work.