Boat

Have Boat Questions? Ask a Boat Repair Expert.

Ask an Expert,
Get an Answer ASAP!

Well my 470 mercruiser 1982 is overheating 240 degree my…

Customer Question
Well my 470 mercruiser...

Well my 470 mercruiser 1982 is overheating 240 degree my heat exchanger must be plugged somewhere not circulating well

Mechanic's Assistant: Sometimes things that you think will be really complicated end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Tell me a bit more about what's going on so the Marine Mechanic can help you best.

Overheat always and make smoke on the carburator sometime is that normal...when i go 1600 rpm temperature goes down a little

Mechanic's Assistant: Is there anything else important you think the Marine Mechanic should know?

I am afraid to go faster

Submitted: 1 year ago.Category: Boat
Show More
Show Less
Ask Your Own Boat Question
Customer reply replied 1 year ago
please answer
Customer reply replied 1 year ago
please answer how can i flush my heat exchanger ?
Customer reply replied 1 year ago
what can i do TO FIX THAT ?
Customer reply replied 1 year ago
OVERHEATING NOT CIRCULATING MAYBE I DID DO IT RIGHT JUST BOUGHT IT ...PLEASE
Customer reply replied 1 year ago
WHERE IS THE THERMOSTAT ?
Customer reply replied 1 year ago
WHAT IS THE IMPELLER DO ?
Answered in 10 hours by:
8/1/2017
Marine Mechanic: Tan, MerCruiser Certified Technician replied 1 year ago
Tan
Tan, MerCruiser Certified Technician
Category: Boat
Satisfied Customers: 11,417
Experience: 40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.
Verified

Hello, I'm Tan. Welcome to JustAnswer. I'm reviewing your question and will reply momentarily.

Ask Your Own Boat Question
Marine Mechanic: Tan, MerCruiser Certified Technician replied 1 year ago

Hello. My name is Tan.

We aren't online all hours of the day so when you post at night many of us are at home with our families.

The water pump impeller # 34 is in the water pump in the lower unit. With an over heat issue we always start with the water pump. http://www.marineengine.com/parts/mercruiser-sterndrive-parts/470-19781982/4893835-thru-6225576/gear-housing-assembly-complete

To flush the heat exchanger you must remove exchanger then take to a radiator shop for flushing. The thermostat # 22 is under the reservoir # 25 of the manifold.http://www.marineengine.com/parts/mercruiser-sterndrive-parts/470-2-bbl-mercury-224-il4-19801982/5520115-thru-6218036/exhaust-manifold-and-elbow-mcm

Post back with questions.

Ask Your Own Boat Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a marine mechanicLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Tan Your Own Question
Tan
Tan
Tan, MerCruiser Certified Technician
Category: Boat
Satisfied Customers: 11,417
11,417 Satisfied Customers
Experience: 40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.

Tan is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Dominick

Dominick

Marine Mechanic

1,009 satisfied customers

25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified

Ted G.

Ted G.

Rigger, Diagnostician

704 satisfied customers

40 years boating, Safe boating instruct., Offshore Race promoter, Failure Analysis, Expert Witness

John White

John White

Marine Mechanic

306 satisfied customers

11 years experience working on outboards, inboards, sterndrives & pwcs

Jason

Jason

Marine Mechanic

17,310 satisfied customers

Degree in Marine Technology. Gas and diesel marine mechanic.

Tan

Tan

MerCruiser Certified Technician

11,417 satisfied customers

40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.

Jeff G.

Jeff G.

Marine Mechanic

4,729 satisfied customers

42 years experience, Certified Master Technician, All Major Outboards, Sterndrives, Hi-Performance

Captain Dave

Captain Dave

Marine Mechanic

2,672 satisfied customers

USCG Licensed Captain, 20+ Years Boating, Fishing, Maintenance and Repair Experience

< Previous | Next >

Related Boat Questions
1982 sea ray 340 with big blocks. One engine overheats above
1982 sea ray 340 with big blocks. One engine overheats above 1600 rpm. I suspect the oil cooler as circulating pump has been replaced... also seawater impeller replaced. I have no idea how to get to i… read more
Boat Doc
Boat Doc
244 satisfied customers
I have a 2014 Mercruiser 5.7 fresh water cooled. It
I have a 2014 Mercruiser 5.7 fresh water cooled. It overheated yesterday. I put a gallon of coolant in tonight and ran it. It stayed at 160-170 at dock idling for 15 minutes. I took it for a ride and … read more
Jason
Jason
Marine Mechanic
Vocational, Technical or Trade Scho
17,310 satisfied customers
Have a re built 5.7 Mercruiser that over heats after 3000
Have a re built 5.7 Mercruiser that over heats after 3000 rpm. risers look clear new outdrive. last time had it out left side felt hotter then right … read more
Jason
Jason
Marine Mechanic
Vocational, Technical or Trade Scho
17,310 satisfied customers
I have twin 1999 Volvo Penta TAD740 with electronic
I have twin 1999 Volvo Penta TAD740 with electronic controls. Recently the starboard engine temperature has crept up and is now running a couple of degrees higher (82c) at 1000 rpm, 88c at 1500 and 90… read more
Jason
Jason
Marine Mechanic
Vocational, Technical or Trade Scho
17,310 satisfied customers
I have a 2008 SeaRay 240 Sundancer with 170 hrs on the engine.
I have a 2008 SeaRay 240 Sundancer with 170 hrs on the engine. She continues to run hot. I was told I need to change the exhaust manifolds. Will changing the exhaust manifolds fix the overheating prob… read more
Jason
Jason
Marine Mechanic
Vocational, Technical or Trade Scho
17,310 satisfied customers
i have a mercruiser 496 mpi 8.1 closed coolant sysem manifold
i have a mercruiser 496 mpi 8.1 closed coolant sysem manifold sensors throw an alarm at about 175 degrees. The engine temp with a temp gun is 165, the manifold are the same and the risers get up to 20… read more
James
James
Certified Marine Mechanic
Vocational, Technical or Trade Scho
4,094 satisfied customers
I have a 1987 Jasper rebuilt 165 4-cyl fresh water cooled engine.
I have a 1987 Jasper rebuilt 165 4-cyl fresh water cooled engine. There is plenty of water flow in the salt eater system (lower unit). The problem is in the engine. When the boat is started the tempat… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,417 satisfied customers
I have a 1988 wellcraft with a 3.7 litre freshwater cooled
I have a 1988 wellcraft with a 3.7 litre freshwater cooled mercruiser engine with a heat exchanger. Presently I'm having a problem with high temps (220+ degrees) at medium to high rpms. The seawater g… read more
Dominick
Dominick
Marine Mechanic
Vocational, Technical or Trade Scho
1,009 satisfied customers
I have a 1984 commando bomber w. mercruiser 470 has new impeller,
I have a 1984 commando bomber w. mercruiser 470 has new impeller, 4'' exchanger & thermostat & it still overheating, Any ideas thanks also confirmed good volume of waterflow thru open loop. Whats a pr… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,417 satisfied customers
I have a kohler marine genset 5E. Changed impeller flushed
I have a kohler marine genset 5E. Changed impeller flushed all lines including heat exchanger. Now it runs 5 mins then shut off and the heat exchanger is somewhat cool but the closed system is very ho… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
11,417 satisfied customers
Mercruiser model 470 overheating, has a closed cooling system. What
Mercruiser model 470 overheating, has a closed cooling system. What to look for. intake impeller? thermostat? Is there a diagram for repair or replace?… read more
Captain Dave
Captain Dave
Marine Mechanic
Master's Degree
2,672 satisfied customers
1984 omc 3.8 liter fresh water cooled. Having overheating issues.
1984 omc 3.8 liter fresh water cooled. Having overheating issues. replaced lower unit pump (looked ok) and circulation pump (impeller a mess). Originally was able to run boat on a plane to keep engine… read more
Jason Forsberg
Jason Forsberg
Outboard Marine Mechanic
Vocational, Technical or Trade Scho
531 satisfied customers
i have a older sangster boat and want to hook an auxillary
i have a older sangster boat and want to hook an auxillary heater to the 470 mercruiser engine is this a safe thing to do ie will the water pump handle the extra fluid movement required and also is th… read more
John White
John White
Marine Mechanic
Vocational, Technical or Trade Scho
306 satisfied customers
I have a 1982 mercruiser 470 that is overheating. We changed
I have a 1982 mercruiser 470 that is overheating. We changed the impeller in foot and it still overheats. What next?… read more
Whitecap36
Whitecap36
Service Manager/Technician
Vocational, Technical or Trade Scho
1,476 satisfied customers
2004 had a new 350 mercruiser installed in 1980 boat always
2004 had a new 350 mercruiser installed in 1980 boat always ran at 180 heated up to 220 upon stopping told by installer of motor that it was normal. This year heated up to 200 would not cool down, sho… read more
mercmastertech
mercmastertech
Service Manager, Master technician
Technical School
249 satisfied customers
I have a 99 Glastron with a stern drive mercruiser 3.0. Just
I have a 99 Glastron with a stern drive mercruiser 3.0. Just recently it started running warm at + 175 before it would always operate at about 140 degrees. I have replaced the water pump in the lower … read more
The Man on the Dock
The Man on the Dock
Marina Owner, Operator
Vocational, Technical or Trade Scho
74 satisfied customers
Over heating problem. 5.7 mercruiser I/O, 1989, open system,
Over heating problem. 5.7 mercruiser I/O, 1989, open system, impeller was replaced 18 months ago, boat has been run at least monthly, I have checked power steering heat exchanger and it was clear. I a… read more
davesoutboard
davesoutboard
owner
Associate Degree
1,570 satisfied customers
Universal diesel engine model 5416 has history of overheating.
Universal diesel engine model 5416 has history of overheating. Currently, system has been flushed, heat exchanger cleaned, new hoses & thermostat & impeller, water pump is two years old, has 50/50 mix… read more
Yachtwork
Yachtwork
Owner Team Yachtwork
Technical or Trade School
1,042 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x