Author Topic: "Would the true cause of the coolant leak reveal themself"  (Read 4933 times)

Offline Greencan

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Evenin' All..

As some will know I have been plagued by persistent coolant leaks since mid February when the radiator began to sprout a few leaks as a result of a bird strike that took out a great chunk of the plastic guard followed soon after by a rock or three...anyway Race Radiators over in Dandenong did a brilliant job in repairing it.

Then while in Tassie the Honda began to take on the characteristics of its British 'shed mates' by marking its territory around Hobart by leaving ever larger puddles of Motul coolant at every intersection :well. The cause here I believed was moi'. I had trapped the reservoir over-flow tube between the frame and the tank, thus over-pressurizing the return and causing a leak from the thermostat by-pass  hose at thermostat end. This was repaired  by 'clipping' 20-25mm from the end of the by-pass hose and fixing with a jubilee clip and relieving the over-flow hose. Problem solved, or so I thought.

Then last Monday after the BDR and while alone in the shed with its above mentioned stable mates it again showed its affection to me by presenting me with a 20ml coolant puddle on the floor.
So a visit to my friendly neighbour over the back fence produced a comprehensive radiator pressure test kit and within 5 minutes revealed a repeated leak from the thermostat by-pass hose at the thermostat end. This time no amount of winding on the jubilee clip would stem the flow at 1.5barr...so off with the hose to reveal a very, very, very cracked hose. Thank you Adam :hatwave

So this is the cause right?...WRONG!!!!

This evening this leak, in particular the rate of the flow we got the other evening when we pressurized the system has bugged me...insomuch that even with the amount of cracking within the hose, the pressure of the jubilee clip proximal to the feral end  the nipple to which the hose attaches should have inhibited the flow considerably, even at 1.5barr! But it didn't.

So I have just returned from the shed having used the flash of a digital camera... and look what it found.


I will remove the housing during the week (time Permitting),  strip it down and run it through the sand blaster (glass), and if it comes up Ok I'll get it TiG(ed).



This photo is of the thermostat by-pass at the OTHER end, where it attaches under the carburettors...Note the amount of perishing



This photo is of the same hose, but cut mid way...still it is considerably perished. I can only speculate to the cause being that flow through this hose is anything but laminar and probable turbulent at best, or more likely stagnant. And thus allowing coolant additive and water to separate and the added concentration of coolant doing the rest. Either way it'll be replaced.

TTFN, the can :)

 

Offline Mitch

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #1 on: May 06, 2012, 09:36:24 PM »
 G'evening  Greencan.
                        First thing I'd do is remove the ST from the vicinity of those other inferior motorcycles to stop them sabotaging your superior ride.  :grin :grin  :grin
               :blk13
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Offline saaz

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #2 on: May 06, 2012, 11:56:54 PM »
First time I have seen that corrosion at the thermostat end..you must win a prize of some sort!

As I have suggested elsewhere, try some EFI hose to replace that bypass hose.  My hose was so brittle it broke when I touched it.  I Won't stop alloy corrosion though...I suspect that the coolant has not been changed for ages and has started to get that electrolysis thing happening that buggers up metal components in the cooling system.
John
(Ridden on and forever in our hearts)
1996 Honda ST1100P
2014 Triumph Trophy SE
Ozstoc, STOC #7239, Farrider #461 Ulysses #061681, IBA #59143 and some others
 

Offline Greencan

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #3 on: May 07, 2012, 07:52:00 PM »
Evenin' All...

Quote
First thing I'd do is remove the ST from the vicinity of those other inferior motorcycles to stop them sabotaging your superior ride.  :grin :grin  :grin

Hi Mitch, You're probable quite right, it's been learning bad habits :eek

Quote
First time I have seen that corrosion at the thermostat end..you must win a prize of some sort!

As I have suggested elsewhere, try some EFI hose to replace that bypass hose.  My hose was so brittle it broke when I touched it.  I Won't stop alloy corrosion though...I suspect that the coolant has not been changed for ages and has started to get that electrolysis thing happening that buggers up metal components in the cooling system

Evenin' John, well that's one 'prize' I can do without at present...Finding EFI hose as you put is only part of the challenge, finding the correct size is of 5.3mm or 5.5mm is my quest at present...Yes, I can source a suitable 5mm part braid hose rated to 4 bar and would do the job but as I am not wishing to remove the carburettors etc to get at the nipple to force it over...I'll persist in finding either 5.3 or 5.5mm hose that will prove less painful for my arthritic fingies to deal with. :(.

Today I abandoned the TiG option after I 'dremeled' out the hole and established just how little metal there is to work with, so have initiated Plan 'B'...DEVCON!

Ehh No, I have replaced the coolant and flushed out the system on 4 separate occasions since 1999...so hence my reference guess to flows / coolant separation previously. Also the internals don't look all that bad from what I can see, and AJ1300 was over this evening (two heads better than one), and I am tending to think along his way of thinking and suspect that it began in a casting flaw; being die cast.

Anyway as mentioned before I now have time on my hands while the Devcon (AJ, I removed the J B Weld after tea...on account the Devcon temp range is known :thumb), takes it's own good time to cure.

Ciao, the can :)

 

Offline laurie

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #4 on: May 08, 2012, 08:27:39 AM »
Dick
I'll swap you..... My electrickery gremlins for your coolant gremlins. Goog deal huh?. I,ll even throw in a set of steak knives. .....and Tasmania......
Cheers
Laurie
 

Online Brock

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #5 on: May 08, 2012, 09:05:33 AM »
Devcon is your friend, I have used it in the past for car fuel tank repairs as well, its good stuff. I was thinking as the housing is that crappy Diecast stuff, welding is out as the metal is a wierd alloy....
Brock
Asian Correspondent
2003 Honda ST1100PY



Ulysses #32829
STOC #8239
OzSToc # ??
Kinross WA
 

Offline Greencan

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #6 on: May 08, 2012, 07:32:15 PM »
Evenin' Guys...

Quote
I'll swap you..... My electrickery gremlins for your coolant gremlins.
Laurie...I have thought long and hard about your offer, so I'll give you the full and unabridged version shall I..."NO!" :grin...I say this as I believe I have a snowball's chance of resolving my 'leaking' 1100, whereas I haven't a hope with electrickery...I'll send me gray :eek

Quote
Devcon is your friend, I have used it in the past for car fuel tank repairs as well, its good stuff
Hi Brock, quite right...Persistence with English two wheeled heritage for moi' necessitated it's introduction to me a while back :wink1

anyway, I prepared for not being able to readily get any 5.3 or 5.5mm ID hose today and the Chaps at my local Burson's gave me a test length of 5mm ID that would do the job, it fits...with a push at the thermostat (easy access end), so I presently working on a plan for me to get it on the 'difficult' end...I have a idea...more latter :wink1

Cheers, the can :)
 

Online Brock

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #7 on: May 08, 2012, 09:01:17 PM »
Soak the hose in boiling water for a few minutes to soften it slightly, it should slide on fairly easily. Maybe use a smear of silastic as a lube/sealant
Brock
Asian Correspondent
2003 Honda ST1100PY



Ulysses #32829
STOC #8239
OzSToc # ??
Kinross WA
 

Offline Greencan

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #8 on: May 09, 2012, 06:46:24 PM »
Evenin All...

I think that the recommended method for replacing this hose is gaining access by lifting off the carburettor assembly however, I am taking the Proctologists approach and coming in from below and from behind :eek


The difficult end

I just aimed the camera and hoped for the best when I took this pic...anyway access is rather tight (as you can see), but  I have a cunning plan which involves the removal of only the airbox (from above), and the petrol tank...more on that latter :wink1.

In the mean time I wont bore you with all the places I have attempted to source either 7/32" or 5.3mm or 5.5mm or nominal 1/4" ID hose within the boundaries of Oz, so I'll tell you you doesn't have it...McDonalds :'(

I am waiting on a couple of return emails to inquiries from the US and the UK, if these don't plan out I have a Mate coming over for tea on Friday who works for a company who does nothing but hose stuff...he has some 5mm ID hose for me, but this is Plan 'B'.

In the mean time the bike will just have to remain is a state of undress and stay uplifted on the bench :(

TTFN, the can :)
 

Offline saaz

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #9 on: May 09, 2012, 07:48:50 PM »
Dick, it takes only a few minutes to pop the carbs off and replace all the hoses with generic parts, especially if you have the tank out already.  I used EFI hose for the bypass and cooler hoses for the main ones.  I suppose you realise that it is also worth replacing the alloy elbows while you are in there.  About an afternoons work In reckon  :think1

I f any offence was caused by these comments, it was probably intended  :beer
John
(Ridden on and forever in our hearts)
1996 Honda ST1100P
2014 Triumph Trophy SE
Ozstoc, STOC #7239, Farrider #461 Ulysses #061681, IBA #59143 and some others
 

Offline Greencan

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #10 on: May 10, 2012, 04:51:57 PM »
Arvo John et al...and top of da arvo' ta ya's all (yardarms obviously past the pole),

Quote
Dick, it takes only a few minutes to pop the carbs off and replace all the hoses with generic parts, especially if you have the tank out already.  I used EFI hose for the bypass and cooler hoses for the main ones.  I suppose you realise that it is also worth replacing the alloy elbows while you are in there.  About an afternoons work In reckon :think1


Well...your quite right of cause it is not too difficult in lifting the carbies off. However, as they have been insitu for 15 years and been subjected to an extensive range in temperature, it would be prudent to replace the individual carburettor insulators (connection tubes). And at present have just purchased a couple of sets of tyres, this is an impost I cannot afford. :'( Also I don't have to :runyay.

Rationale:

Corrosion.
Now that the fuel tank is out and viewing within the 'V' is unencumbered (no emission clutter), so I can easily visualize all that needs to be seen by using a torch and a mirror, which includes  the two elbows that return coolant from each of the cylinder heads. Now corrosion (like fire), needs more than one element for it to occur and in this case it's air (O2),  so what to look for is evidence that air is getting into the system proximal to the area of corrosion. In most cases if you see the tell tale powdery crystals clumping around a hose fitting (or in this case at the TBP return end, a persistent leak that I put off repairing properly...Doh!), it's indicative that coolant is weeping out when hot (expansion), therefore air can get in as the engine cools (contracts). So as (in this case), the return elbows are in close proximity to the just mentioned joints it's logical that if signs of corrosion are visible externally, then there's a fair bet it's well entrenched on the inside as well.

Now back to those two elbows which have right angle bends. Any bend will inhibit laminar flow, thus increase the likelihood of coolant / water separation (turbulent flow),  and I figure by the time a persistent leak is detected in this area, it's usual a cracker, as weeping from here can go on for years (if not inspected), undetected as any coolant / water will have evaporated in this location and been replenished courtesy of the reservoir tank without notice.; so air will 'trap' at the elbow and do its work while the engine is not running .  Perhaps this is why the elbow can get severely corroded and the cylinder head its attached does not.

There is absolutely no evidence of coolant weeping from these joins on this bike. Why, because I used a 6mm spanner to tighten the jubilee clips one quarter of a turn when I last had the tank out (to remove debris), some years ago. This quarter turn was enough to compensate for natural compressive hardening of the rubber hose at this point.  Speaking of which...


I will be using the OEM spring clip and not the jubilee clip on the replacement hose, which it would seem, will be this one in the photo...only a tad longer :thumb. Has at a guess why? :think1

Hoses.
I, like many others am of the belief that in all likelihood OEM hose 'A' and aftermarket hose 'B' probably came out of the same factory, in China, somewhere. I DON'T hold to the notion that OEM parts are dearer simple because they're OEM, particularly in the US (think about it). I DO believe that you can get two 'parts' that look identical, but they are not; I know this from bearings . I therefore rationalize that Honda parts are of a superior material and build. Also it is visible light (as well as heat), that will deteriorate rubber and I think it's fair bet that not too much light gets to these hoses.

Presently that return hoses from the cylinder heads are both supple and without any evidence of cracking at their ends, so I rationalize they are still serviceable albeit on a 'time extension'. So for now, they stay.


Left cylinder coolant return joint...the nut of the jubilee clip is to the top


Right cylinder coolant return joint...the nut of the jubilee clip is to the top

The above 2 images are poor quality as there were taken from a live stream from a USB cable camera going directly to the computer in the shed. $60 number from JAYCAR...cheap but gets into wee difficult places well :thumb

Quote
I f any offence was caused by these comments, it was probably intended  :beer


Nah! For a Public Servant that (I considered), worked for the enemy >:(, in Canberra, for an Organisation that once demanded of me to produce receipts that went back further than my  pre-embryonic state...ya did bring a rather better bottle of red with you to share at Blackheath than I did :thumbs.

TTFN, the can :)

 


 

Offline saaz

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #11 on: May 10, 2012, 05:20:31 PM »
I am not a public servant anymore  :runyay :runyay

The generic heater hoses I used are far more robust than the Honda ones I took out.  Another 10 years life will do me I suppose.

As for those reds your bought..they tasted better as the day went on.... :whistle

I have been out looking at hybrid bicycles to start getting some fitness going while I am inbetween rides etc.  Doing my thinking at the watering holes inbetween bicycle shops sorta defeats the purpose...
« Last Edit: May 10, 2012, 05:22:41 PM by saaz »
John
(Ridden on and forever in our hearts)
1996 Honda ST1100P
2014 Triumph Trophy SE
Ozstoc, STOC #7239, Farrider #461 Ulysses #061681, IBA #59143 and some others
 

Offline Greencan

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #12 on: May 10, 2012, 05:25:12 PM »
Quote
I have been out looking at hybrid bicycles to start getting some fitness going while I am inbetween rides etc.  Doing my thinking at the watering holes inbetween bicycle shops sorta defeats the purpose...


Here's one, but be quick :wink1..wouldn't want U to miss out!
http://www.ebay.com.au/itm/NEW-HUDSON-AUTO-CYCLE-1956-/120907262312?pt=AU_Motorcycles&hash=item1c26a26968
 

Offline Greencan

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Re: "Would the true cause of the coolant leak reveal themself"
« Reply #13 on: May 20, 2012, 05:50:32 PM »
Arvo All,

Well tis all back in fine working order again and a not without a big thank you to AJ1300 for getting me the pressure test kit that worked a treat...over a 12 hour period was able to detect  2 other small weeps that were easily rectified with a 1/4 turn of the respective jubilee clips :thumbsup.


The cunning plan revealed...

As there isn't any anti-emission fixtures on our 1100's, access with one hand to where the hose terminates under the carburettors is unencumbered..so all that remains is being able to bear pressure to the hose to get it to over the 'nippled' fitting.

This method worked a treat...I taped the hose to the screwdriver, but it could have easily been with another jubilee clip proximal to the end and within 30mm of the end of the hose, in order to be able to release it from the hose once it is insitu...so all I needed to remove was the air box only.

Oh and the DEVCON worked as I knew it would :grin.

Cheers, the can :)