cooling system

[BP]

I had that leak coming home from my friend's garage after doing front engine renewal project, I had originally thought because the cap was not seated properly. it barfed water all over the place when I pulled over at the walmart stopped and cut the engine, it continued to pour out from the radiator cap.

re-filled with distilled water, and ensured the cap was seated proper.

it is cooling efficiently, the problem being the dripping with the stant 10229 radiator cap. it was dripping when I arrived back to my garage and I let it idle, the dripping stopped.

I let it cool for a few hours. went back and idled it to hot, right before the fan turned on, six drops of water. six.
went through three fan cycles, couldn't detect any more water.

should I just put coolant and go with it, assuming that lower boiling point of coolant won't break the 13-lb seal as the water ever-so-slightly does,

or investigate further what the problem is?

 

[Steve83]

Are you sure the lip inside the radiator neck that the cap seats against isn't dirty, damaged or corroded?

 

[joedrum]

boy its seems borderline on operation and either something is up with cap or thermostat is not opening soon enough ... id watch it big time ...fan switch involved here to ...once it starts loosing water its just get worst

 

[weightlifter99]

My 82 doing the same thing but only stated after I refilled the reservoir jug up top. Then when it leaked out down to the same level the jug was before refilling the leak has now stopped. WTF? Is the level in the jug a control for the level in the system? Mine hasn't leaked a drop since the jug level has returned to where it was. I don't get it. Its a closed system and the cap lets coolant back and forth between the radiator and the jug depending on temp and pressure. So why and how would this do this? Radiator and system is full. Now my gauges are not operating properly, 7 volt thing, and fan is turning on and off at idle like I think it should. Maybe t-stat letting system get too hot and over pressurizing system? But then why would it quit leaking when the level dropped? Any ideas?

 

[BP]

easy first check steve, will do

weightlifter - you gave me the lightbulb, i DID overfill the resevoir tank up top, bigtime.

I just replaced with duralast thermostat.

the evidence suggests it might get hottest just before the first fan cycle then the later fan cycles turn on at a lower temperature.
now, that doesn't make sense, but that's what it looks like. the fan switch being the last part to get hot is one explanation, thermostat a second option.

never lost any water before this project and the thermostat did change... hmmm...
we ran it plenty with distilled water at my friends garage and saw nothing, but I filled the radiator and left the upper jug empty, because I knew that that fill of water was coming back out.

I must have got too excited pouring the water for the ride home, it is way overfilled.

going to try to re-create the problem after inspecting and re-seating the radiator cap and proper water level [between low and high on top jug]
If it happens again, then we know who's to blame (thermostat)
if I get to this step and pull thermostat, and it still leaks, I'll just use the wrench to bang my own head. :head bang: :head bang:

 

[dan filipi]

Nah, it's not a thermostat problem or over filling the recovery, there's a problem with that cap sealing properly on the radiator.
Do you have the old one to try? I'm not real fond of these supposed 'campatible crossover' parts.

 

[BP]

dang I will try old radiator cap, haven't made it out of the house yet.
sure sucks getting all of these parts and then having problems with fitting them/not even using them.

it seems that the old cap was of different construction somehow, but the new one ran without leaking for a long time. anyhow the old cap is going to be the way to go as a first test.

 

[BP]

swapped radiator cap for the old one.
three cooling cycles and bone dry.

:rant: brand new radiator cap *$(% @#$@ :rant: :rant:

I'm going to ride to work today, short shift on Independence Day, and see how that goes.

What is strange to me is that the new radiator cap had zero issues for a few weeks before I was able to dig in to renewal project. then again I was running coolant/antifreeze and not distilled water, which may have been the difference - same temperature, one boils and the other does not.

I think after a quick visual inspection that the top gasket is too thick on the new cap (and I figure the 13lb rating is for the bottom portion gasket) and the bottom part of gasket poorly seats because of the increased height from top gasket, leaving top gasket with a 'zero' psi rating as the only sealing portion of the cap.

 

[dan filipi]

As far as radiator caps go, if the sealing rubber doesn't show cracks when bent over on itself, I run with it. I think the spring is rarely an issue.

 

[weightlifter99]

Dan on mine the cap is the same and hasn't been changed since I've had the bike. It only started leaking after the "overfill" on the recovery tank. Once it leaked back down to the level it was before the coolant addition the leak has now stopped. Haven't removed or messed with the cap. This has me baffled. Fan cycles on and off.
And also was wondering of what BP said about his fan cycling. Longest on the first then sped up temp wise on each succeeding cycle. Reckon there may be some coating on the sensor that takes a little heat to overcome and activate the sensor? I have seen this on cars before that has affected the cycling times. I have removed them and cleaned them with a brass brush and some carb or brake cleaner and when reinstalled have worked properly again.
I know that a lot of parts on these oldwings are very similar to auto parts so was just curious there.

 

[joedrum]

blacklander had cooling problems ... hes sense did what i did ...toss the thermostat....hes beem on a ride and i guess it was ok cause no mention of geting hot on his ride report ... personally i dont risk the oldwing motor to thirty year old wires an such in irreplaceable motors ... tossing the thermostat lowers this danger zone and is where i chose to play

 

[weightlifter99]

Sounds like a safe idea Joe and I'll prolly turn this avenue and follow down this street also. I suppose you have nary a problem with warm ups? Gets to op temp or close fairly quickly?

 

[backlander]

No problems so far without the thermostat, haven't had a chance to put the custom radiator side scoops on instead of the lowers and it runs perfect midrange temp just like it is without them.

 

[BP]

weightlifter99 » Sat Jul 05, 2014 5:19 am[/url]":1bre3ws8]
Dan on mine the cap is the same and hasn't been changed since I've had the bike. It only started leaking after the "overfill" on the recovery tank. Once it leaked back down to the level it was before the coolant addition the leak has now stopped. Haven't removed or messed with the cap. This has me baffled. Fan cycles on and off.
And also was wondering of what BP said about his fan cycling. Longest on the first then sped up temp wise on each succeeding cycle. Reckon there may be some coating on the sensor that takes a little heat to overcome and activate the sensor? I have seen this on cars before that has affected the cycling times. I have removed them and cleaned them with a brass brush and some carb or brake cleaner and when reinstalled have worked properly again.
I know that a lot of parts on these oldwings are very similar to auto parts so was just curious there.

Yes that is accurate about the fan cycling, it gets hottest just before the first fan cycle [just over 1/2] and all subsequent fan cycles start right at 1/2.
I will have to try that solution when I get a chance. Additional information, my top tank is still overfilled, and still no leaks, with old radiator cap.