Good job on the repair and the video. I have a '95 Merc 502EFI and tstat assembly looks quite similar. I am replacing the sea water pump and will be checking the tstat. Thanks.
MaxSpeed Track Days Garage quick question though, my buzzer (alarm)is going off what would be the cause of that? Do you know? I see my thermometer is not getting the right reading since I put a thermostat in..
Justin Sullivan I’d check that the washer with the copper grommets in it is good. Make sure you’re getting good conductivity through there so the temp sensor can give you an accurate reading. If the temp sensor is bad, change that and see if you continue to get the alarm...
MaxSpeed Track Days Garage thanks! Update the alarm was another issue but it went away but now the temp gauge is not reading right. It’s reading 190-200 degrees as soon as you start it up. After checking with a IR thermometer the temp at the sensor gets bout 155ish when at its hottest. Then the gauge will read closer to 240. May be a issue with the sender. Thanks for the help!
Justin Sullivan could be that your gauge is bad as well. There’s a way to check that by grounding the temp sensor wire... I can’t remember the correct procedure off the top of my head, but I found it originally on the iBoats forums. Hope you get it figured out...
The last thermostat kit didnt give any brass fitting on the o rings and lasted about 4 trips running about 25 miles each time. Alarm started blarung the 30 minute ride back was annoying so I gave it some hass and 25 knts in no time
If you're still getting any erratic engine temperature as it sort of looked liked it to me in your video, then you should try using the cork gasket inside the T/Housing as that is the correct gasket to use on this T/housing design....The O-Ring was more meant to be for the older design T/housings from Mercruiser.
You sound exactly like Danny McBride...hopefully you can take that as a compliment, cuz Danny McBride is awesome! ...oh, and thanks for the Mercruiser thermostat instructions.
Thank you for a great video! How is the boat running? Is the temp fluctuation normal? My boat is doing the same after I replaced all the hoses and raw water pump and I can't remember if the fluctuation was happening before or not. I am planning to replace the thermostat just in case since it is 9 years old.
nelaco1 Thanks for the compliments! Yes, boat is running great, temp stays rock solid at 180 degrees when running at 30-35 mph (gps) If your thermostat is 9 years old I definitely recommend replacing it. Along with the impeller and such.
@@_FlyingScotsman_ , great to hear. Yes, I've replaced all the hoses, raw water pump, and impeller. Today I'll replace the thermostat. The temp fluctuation has me a little worried so I am hoping a new thermostat will take care of it. I don't know yet how she is doing on plane since I haven't launched for the new season yet. Take care.
great video. im having overheating problems with my boat. is there anyway you could show the rout of the belt i wanf to make sure my belt is in correctly seems like we have the same engine. i have a 1997 mercruiser. i would really Appreciated it
Thanks for the compliments. Unfortunately I’ve sold that boat as of last year. You should be able to look up a belt routing for the 5.7 Mercruiser. Try iBoats.com and the forums there.
Good video just wish you would show all the steps and if had gaskets left over as I figure this is a universal kit mine is just like yours so I just need 2 gaskets and oring
chris ciraldo Not sure what “cap” you’re talking about. I only had to use the o-ring and plastic sleeve inside the housing and one gasket where the thermostat housing bolts to the engine.
Lake Ontario Boater - I had read a lot and spoken to guys on my Chaparral Forum, so I expected the sleeve/spacer to be stuck or that I would have to break it to get it out. They’re cheap, so I had one on stand by. I didn’t expect mine to be missing which explained the erratic temp readings when I first put the boat on the water. Happy to report that a year into ownership she’s doing great and we’ve enjoyed a lot of use out of her!
@@_FlyingScotsman_ That may very well be the case; however, anyone else who wants to follow this video, should know that the proper way to install a MerCruiser thermostat is opposite to the way that you show in the video.
@@Jazzy4now Sorry Jazzy but you are wrong. The spring portion of the stat is the bottom, the short part that comes to a point is the top. Max is working with the housing upside down so the point would go in first. When turned right side up and installed point will be on top, spring on the bottom just as it should be.
It only did that on the initial thermostat openings. Boat has run perfectly for three years since this video and I’ve never seen it above 180°. We use it about three times a month from May to October in Georgia.
Mike Haley - I did not use any sealant. Your design may be slightly different, but in mine sealant is not recommended due to the brass rivets in the gasket that aid in electrical conductivity for the temp sender and the alarm temp sensor.
Good job on the repair and the video. I have a '95 Merc 502EFI and tstat assembly looks quite similar. I am replacing the sea water pump and will be checking the tstat. Thanks.
Mel Robinson Thanks for the compliment and I hope the video helps you out...
Great video. My gauge isn't working. Have some investigating to do. 1 riser gets pretty warm. I took it apart and it looked really good🤷🏽♂️
thanks phil couldn't find any video showing how to do this but yours.
Glad I could be of some help Steve!
I have the EXACT same boat and this video helped me to a T. Thanks fella!
Justin Sullivan You’re welcome, glad it was useful...
MaxSpeed Track Days Garage quick question though, my buzzer (alarm)is going off what would be the cause of that? Do you know? I see my thermometer is not getting the right reading since I put a thermostat in..
Justin Sullivan I’d check that the washer with the copper grommets in it is good. Make sure you’re getting good conductivity through there so the temp sensor can give you an accurate reading. If the temp sensor is bad, change that and see if you continue to get the alarm...
MaxSpeed Track Days Garage thanks! Update the alarm was another issue but it went away but now the temp gauge is not reading right. It’s reading 190-200 degrees as soon as you start it up. After checking with a IR thermometer the temp at the sensor gets bout 155ish when at its hottest. Then the gauge will read closer to 240. May be a issue with the sender. Thanks for the help!
Justin Sullivan could be that your gauge is bad as well. There’s a way to check that by grounding the temp sensor wire... I can’t remember the correct procedure off the top of my head, but I found it originally on the iBoats forums. Hope you get it figured out...
The last thermostat kit didnt give any brass fitting on the o rings and lasted about 4 trips running about 25 miles each time. Alarm started blarung the 30 minute ride back was annoying so I gave it some hass and 25 knts in no time
Was that a quicksilver kit? Mine came with all kinds of extra stuff. Picked it up from my local marina maintenance shop.
If you're still getting any erratic engine temperature as it sort of looked liked it to me in your video, then you should try using the cork gasket inside the T/Housing as that is the correct gasket to use on this T/housing design....The O-Ring was more meant to be for the older design T/housings from Mercruiser.
This is 100% correct. Gaskets installed improperly
You sound exactly like Danny McBride...hopefully you can take that as a compliment, cuz Danny McBride is awesome! ...oh, and thanks for the Mercruiser thermostat instructions.
Jerrit Tyler - Thanks! I don’t know who Danny McBride is but I’ll look him up! Glad I could be of some help for you...
Thank you for a great video! How is the boat running? Is the temp fluctuation normal? My boat is doing the same after I replaced all the hoses and raw water pump and I can't remember if the fluctuation was happening before or not. I am planning to replace the thermostat just in case since it is 9 years old.
nelaco1 Thanks for the compliments! Yes, boat is running great, temp stays rock solid at 180 degrees when running at 30-35 mph (gps) If your thermostat is 9 years old I definitely recommend replacing it. Along with the impeller and such.
@@_FlyingScotsman_ , great to hear. Yes, I've replaced all the hoses, raw water pump, and impeller. Today I'll replace the thermostat. The temp fluctuation has me a little worried so I am hoping a new thermostat will take care of it. I don't know yet how she is doing on plane since I haven't launched for the new season yet. Take care.
great video,thx
Thank you sir , put more related videos .......
Linson varghese , kuwait
great video. im having overheating problems with my boat. is there anyway you could show the rout of the belt i wanf to make sure my belt is in correctly seems like we have the same engine. i have a 1997 mercruiser. i would really Appreciated it
Thanks for the compliments. Unfortunately I’ve sold that boat as of last year. You should be able to look up a belt routing for the 5.7 Mercruiser. Try iBoats.com and the forums there.
Are you sure the thermostat doesnt go the other way in the housing?
andrew andreou - The thermostat is installed properly and the boat has been running great for two years!
@@_FlyingScotsman_
No according to this manual it li the right way.
www.mercruisermotor.com/files/5_7LEFI_01_B.pdf
Page 28 #5
Great video sir
Good video just wish you would show all the steps and if had gaskets left over as I figure this is a universal kit mine is just like yours so I just need 2 gaskets and oring
chris ciraldo I did have gaskets left over. Only gasket I used was the one with the small brass contacts in it plus the o-ring and the plastic sleeve.
Doesn't a gasket go on top also for the cap?
chris ciraldo Not sure what “cap” you’re talking about. I only had to use the o-ring and plastic sleeve inside the housing and one gasket where the thermostat housing bolts to the engine.
You are missing the block off gasket for the top plate that comes off
chris ciraldo Hmmmm... Not sure ours are exactly the same then. Been running mine this way for 3 years, no issues, no leaks.
Nice. You're lucky you didnt have to take out the old spacer, mine is stuck in good.
Lake Ontario Boater - I had read a lot and spoken to guys on my Chaparral Forum, so I expected the sleeve/spacer to be stuck or that I would have to break it to get it out. They’re cheap, so I had one on stand by. I didn’t expect mine to be missing which explained the erratic temp readings when I first put the boat on the water. Happy to report that a year into ownership she’s doing great and we’ve enjoyed a lot of use out of her!
on my boat you use the gasket in the kit not the o-ring 350 MAG MPI
Mike Dodd Cool, I guess that’s why they provide multiple options inside the kit. Nice to not have to make multiple trips to the parts guy. 👍🏻
When you put all your hoses back on do you have to bleed the system to get air out or just hook up the flush hose for a few
Foulmouthflicks - I just hooked up to the flush and tested that the thermostat was operating properly... No bleeding involved...
wow man your quick at taking bolts out and I could use you in my shop lol..
LOL... I hear that a lot!
That thermostat is installed upside down. According to the MerCruiser Service Manual the thermostat element goes in the opposite way.
It’s been working perfectly since I installed it. Keep in mind I have the thermostat housing upside down on the video. Thanks for the input...
@@_FlyingScotsman_ That may very well be the case; however, anyone else who wants to follow this video, should know that the proper way to install a MerCruiser thermostat is opposite to the way that you show in the video.
@@Jazzy4now Sorry Jazzy but you are wrong. The spring portion of the stat is the bottom, the short part that comes to a point is the top. Max is working with the housing upside down so the point would go in first. When turned right side up and installed point will be on top, spring on the bottom just as it should be.
It shouldn't be going up and down like that. Think about your car. Does your temp gauge do that in your car? You have another issue somewhere.
It only did that on the initial thermostat openings. Boat has run perfectly for three years since this video and I’ve never seen it above 180°. We use it about three times a month from May to October in Georgia.
💪😎🇺🇲
Did you use any sealant on the gasket?
Mike Haley - I did not use any sealant. Your design may be slightly different, but in mine sealant is not recommended due to the brass rivets in the gasket that aid in electrical conductivity for the temp sender and the alarm temp sensor.
Use a film of grease on each side of the gasket
I don't think the temp is supposed to be that erratic. lol I have a newer MPI 5.7 engine and it goes up to 165-170 and stays there.
You are exactly right. Mine does too. I would be interested to see if it does the same off the hose?
so my 5.7 mercruiser goes up to like 180 i was dondering if that is too hot. book says 160 and i belive i installed a 160 tstat