Re: Leaking coolant in my 81C
Technical Help Forum
Leaking coolant in my 81C
Anonymous
07-19-2008, 2:23 PM
Guys, need your opinions on a coolant leak in my 81C. It starts to leak almost as soon as it is started, I have posted a picture of the lead here
http://humbossblog.blogspot.com/
Sorry I can't seem to figure out how to get a picture in a post. Please copy and past and click on the picture for the big view!
Is this the famous mechanical seal I've read so much about here. Picture is taken from behind the engine on the left side...looks to be right behing where the solid coolant pipe enters the pump housing.
Thanks..
Barry
Re: Leaking coolant in my 81C
WisconsinCX
07-19-2008, 2:24 PM
Sorry, forgot to log in.
Barry
83 650 Silverwing Interstate Phoenix
81 Deluxe
80 Custom
78 Maggot
Re: Leaking coolant in my 81C
the cheese
07-19-2008, 2:38 PM
It could be coming from the transfer pipe o-ring, housing gasket, or the weep hole. Try to clean it up vey good. See were its coming from then go from there.
1981 CX500 Custom
Just say no to skin graphs, wear your gear!
Re: Leaking coolant in my 81C
fll1441
07-19-2008, 2:47 PM
That could be a leak from the mechanical seal weep hole. But, sometimes a leak from the chrome water pipe O ring, or even water pump housing gasket may show at the same spot. First, have a look at Rob's web page. I'll post a link below. Go down the page and look at the pictures and drawing. That will give you a good idea where the weep hole is. If you shove a wad of paper towels up under the weep hole it will help you tell if that is where the coolant is leaking. Make sure you get the towels up above where the water pipe fits in to the pump housing. Then go for a ride. If you see coolant leaking, but the towel is dry, you know the leak is not from the weep hole. If the towel is stained with coolant, it's a mechanical seal leak. If it is the mechanical seal, I recommend Shep's method. It's the second link below. I used a Yamaha seal. It was about $18 at a local dealer. If you're interested, I'll post the part number and some tips on getting the new seal apart.
http://www.elsham.pwp.blueyonder.co.uk/cx500/mechanical_seal/
http://www.geocities.com/sheppola/cx500/mechseal.html
1982 CX500 Custom
Re: Leaking coolant in my 81C
WisconsinCX
07-19-2008, 6:23 PM
Well, I pulled the carbs and related items so I could take a good gander at the area of the leak. Sure enough its the weep hole. Looks like I'll be rolling my sleeves up and doing a seal replacement soon.
Barry
83 650 Silverwing Interstate Phoenix
81 Deluxe
80 Custom
78 Maggot
Re: Leaking coolant in my 81C
fll1441
07-19-2008, 6:53 PM
The Yamaha seal part number is YA11H-12438-10-00.
A new gasket for the water pump housing (I think Honda calls it an O ring) and a new cap nut and copper washer for the cam shaft end are handy to have if you are ordering any parts. You may be able to reuse the old gasket. It's basically a long, thin O ring. But, mine was kind of oval when I got the cover off. So I replaced it. If you don't get a new copper washer, heat the old one to soften (anneal) it so it will seal well. Below is a link that shows how to cut the cup with a Dremel to remove the guts from the new seal. That and some heat works well. Don't force the innards out of the new cup or the rubber will tear.
http://choppercharles.com/cs/forums/10938/ShowPost.aspx
1982 CX500 Custom
Re: Leaking coolant in my 81C
DaveF
07-19-2008, 6:59 PM
If it's a very slow leak there's no need to dig into it anytime soon. Just keep an eye on the coolant level. If it
stops
leaking check to make sure the weep hole is not plugged.
My GL500 started leaking a few drops several months after I bought it new in 1982. After a couple of decades and many thousands of miles I finally got around to replacing the mechanical seal. And only then because I had other reasons to crack open the engine.
My Home Page
1981 GL500I
1982 GL500I
1983 GL650I
Re: Leaking coolant in my 81C
WisconsinCX
07-19-2008, 7:39 PM
Thanks guys, this is more like a small flow!
83 650 Silverwing Interstate Phoenix
81 Deluxe
80 Custom
78 Maggot
Re: Leaking coolant in my 81C
Ayal
07-21-2008, 5:35 AM
Some people only replace the rubber boot+spring+slider, but leave the original metal cup intact. It bypasses the worst part of the job.
Strive to learn something new every day
Copyright 1978-2006 Charles E. Smith