best way to check for blockage in cooling system

[Andy in NY]

1970 evinrude 85 hp


i think there may be bees in the cooling system. on 2 different occasions i have heard buzzing from the engine! no battery hooked up so i know its not an electrical short. i'll be replacing the impeller today, as when i ran it last week it didnt seem to be pumping water. i want to blow some air through the system to make sure there are no blockages, but where should i pump the air in???

in between the cyl heads there seems to be a hose coming from both and connecting to a square box right in the middle. whats in this box?

 

[tashasdaddy]

Re: best way to check for blockage in cooling system

i would drop the lower unit, and remove the tstats. use a water hose to flush both ways. Bees have been known to nest in the mid section of the motor.

 

[cajuncook1]

Re: best way to check for blockage in cooling system

1970 evinrude 85 hp


i think there may be bees in the cooling system. on 2 different occasions i have heard buzzing from the engine!

Wow, Evinrude honey, never tasted that before....lol. Sorry couldn't help my self.

Check your intake holes/vents to make sure they are not occluded with mud or trash. My dad had a 55hp that had a wasp nest in the hood and lower units. I remember getting stung up trying to clean that out years ago. It was worth it though, caught a ice chest full of blue gill and sac-a-lait (crappie) that next day.

Sorry, reminiscing , but also check the exhaust port as well and if you have tell tale. Those are nice places the wasp like to make nest in as well. Its probably time to change the impeller as well.

The other questions you have will have to wait for an experienced person regarding that make an model motor.

Good luck to you!!

 

[Andy in NY]

Re: best way to check for blockage in cooling system

i would drop the lower unit, and remove the tstats. use a water hose to flush both ways. Bees have been known to nest in the mid section of the motor.

i havent gotten a manual for this motor yet... where are the tstats on it?

 

[cajuncook1]

Re: best way to check for blockage in cooling system

Sorry TD, was typing this and getting the kids ready for school and breakfast...didn't see you respond.

cajuncook1

 

[cajuncook1]

Re: best way to check for blockage in cooling system

i havent gotten a manual for this motor yet... where are the tstats on it?

Look at this link, it may help out.

http://www.boats.net/parts/search/BRP/EVINRUDE/1970/85093B 1970/EXHAUST COVER GROUP/parts.html

 

[Andy in NY]

Re: best way to check for blockage in cooling system

okay that helps... the "box" that has a hose coming from each cyl head is where the tstats are... thats where i suspect there are bees.... although it almost sounded like it was inside the water jacket in the head!


ill be working on this later today as well as replacing the impeller. hopefully all goes well and i dont have any major blockages.


this motor sat for about a year so theres a good chance theres a nest, plus it was in my garage for about 2 months which is notorious for bees...

 

[cajuncook1]

Re: best way to check for blockage in cooling system

Hey Andy in NY,

Check out this information that was posted on this forum...but in another thread. Look for the condensed manual for your motor and that might help you out some until your ordered manual gets to you.

It is a Free service and open to public and LOADED with helpful Information, Manuals, Service data etc..!

Go to: http://search.ebscohost.com/

Log in with:

Name: marshall

P.W. : public

-----Go under the Small Engine Repair Reference Center

-----Then select Marine/Boat motors

----- EVINRUDE/JOHNSON

-----OUTBOARD 4-CYLINDER MODELS 85 HP (PRIOR TO 1987) (should be your motor in here)

Scroll through the list of makers/manufacturers

Search by type, brand, etc. They are all in PDF format so you can save them for future refference....

A GREAT FIND !!

Hope this helps ya!

 

[Andy in NY]

Re: best way to check for blockage in cooling system

Hey Andy in NY,

Check out this information that was posted on this forum...but in another thread. Look for the condensed manual for your motor and that might help you out some until your ordered manual gets to you.



Hope this helps ya!

wow awesome thanks!

 

[Andy in NY]

Re: best way to check for blockage in cooling system

well i have good news to report, there was no blockage, and there was no bees nest IN the cooling system...


it was just underneath the tstat housing...


after an impeller change, she was pumping water just fine, sans the cracked cooling hose going to the starbord side head. ill get a new one and be back in business.

 

[cajuncook1]

Re: best way to check for blockage in cooling system

Well, glad you sorted out your problem!! I enjoyed the rebuild work you did on your boat displayed on your listed threads.

 

[Andy in NY]

Re: best way to check for blockage in cooling system

Well, glad you sorted out your problem!! I enjoyed the rebuild work you did on your boat displayed on your listed threads.

thanks. this motor is a repower for that boat. i got this motor cheap... $150. guy *said* it was running when they took it off another boat. but after i dragged it home i realized it had alot of broken parts and missing parts. so far the trim pump was leaking, but thats fixed and the bracket is broken, so its currently held on by a hose clamp... the throttle cable was broken so i used one off a different motor but its too short so ill order a new one once i make sure she performs...the hood is missing the weatherstripping, i think i will use some rubber hose sliced down the middle... the 2 mounting brackets were missing, they should be arriving from ebay monday... the battery cables were toast, but im making some new ones... now i have to replace one of the cooling hoses... oh and when i got it home it wouldnt start, popped the flywheel and cleaned the points and she fired right up.

im hopeful for a good showing on the water... shooting for at least 40 mph...


but at this point im into it for under $300, and i sold my 50 for $550, and i didnt pay for that motor, i traded the 55 johnson that was on it that ran like crap for it... so im ahead of the game at this point.

 

[older]

Re: best way to check for blockage in cooling system

I'm working on a similar problem on a 15 hp Evinrude. I replaced the pump and impeller yesterday and still no water coming out of the pea hole. I'll have to remove the pump and look into the inlet under the pump.

I tried a method I found on the web that said to hook up a water hose, but not full pressure to the tube that fits the water jackets on the upper housing to see if water comes out of the pea hole and it does, so now I know that the thermostats (and bypass valve) works, so I'm sure it's something in the lower unit.

This is a helpful link:

http://www.sschapterpsa.com/ramblings/Johnson 9.9_15.htm

Good luck.