Heavy coolant leak.

[longerone]

My 04 pan European (60K odo)exhibited minor coolant leak a while back, it seems to correct itself. I have to admit the bike doesn't see much riding perhaps a short ride every 5 weeks on average. I parked it for 2 months, after which i started the bike to warm it up for a ride, on reaching 3 bars coolant came gushing out from the lower fairing, i top it up and rode it in town, due to i have to change bikes storage location. Coolant still leaks at stops and i topped the reservoir,parked the bike overnight and when i check the reservoir bottle it is full to the brim, i took the bike for a short ride and temp reached 4 bars for the first time ever.
I really need your sage advice, i couldn't tear the fairing apart to locate leak, but i think i need to change all coolant hoses and thermostat, as it probably was never changed by first owner. Letting the bike seat for long periods could contribute?.
I intend to purchase parts from RONAYERS and hoe they will be compatible with the Pan European version of the ST.

 

[SupraSabre]

If you raise the tank, remove the airbox, you can pull the rubber dam away from the front which exposes the thermostat housing and hoses. Check those connections first. If it is coming out as fast as you are explaining, it shouldn't be too hard to find.

Good luck..

Make sure you have a couple of hundred miles on the gas in the tank, if you try to tip your tank when it is full, it WILL come out the gas cap...DAMHIK! 4:

 

[Scooter]

A couple of questions. Are the cooling fans turning on? When was the coolant changed in the past?

Just putting coolant into the overflow botttle doesn't mean that it is going to end up in the system especially if you are low on coolant in the engine, which I suspect you are, and that's the reason why you are seeing four bars appear on your thermostat. It's a shame that you can't easily access your radiator cap because if you could you'd likely find your level is down.

Seems like a lot of coolant leaking for just loose hose clamps. But then again, it sounds like yours sits alot. I'd probably do just what Bob recommends and try to see if the leaks are coming from the hoses on top. There will be telltale signs if that's the case. Good luck and keep us posted...

 

[longerone]

Ok sirs thats exactly what i intend to do, probably tomorrow.

 

[longerone]

Finally removed the lower cowl today, guess what i found, rust have eaten up the iron pipe attached to a hose on the water pump housing cover. I believe this rusted pipe is attached to the water pump cover($200) and not detachable.
Do you think thats all i need to change? the pump cover that is it.
I have been topping with water only, as i couldn't find the silica free coolant and i have not taken a long ride for a while. So the coolant is mostly water coupled with long spells of bike sitting down idle could contribute to the rusting.
As i have to wait a month receive the parts, should i drain the remaining coolant(mostly water) in order to forestal further rusting.

 

[okmurdog]

You most likely have more damage in other portions of the coolant system/engine than just that one area if the coolant mixture has been mostly water. Probably also have a damaged thermostat, and possibly other components.

An entire inspection and possible overhaul of the coolant system is in order.

 

[970mike]

You will need to pull the radiator out and check all hoses and connections for rust. I would replace the thermostat also along with all hoses and clamps. Good luck and keep us posted.

 

[acedantinne]

Nasty leak at the WP cover fitting. Behind is a o-ring. Hope that & some hoses, t-stat, o-ring good flush and your back on the road?
I'm replacing my WP now. Just 1 cover passed The cover with the hose fittings on it. Added some pictures with rad off. If found what led to failure. Bad thermostat. This is mop.

 

[longerone]

Thank you for your help. I plan to change the WP cover thermostat and the major hoses as well as flush the system. Below is the list of items i intend to replace. Any more advice will be greatly appreciated.
MFG
ITEM
QTY
PRICE
TOTAL
Honda
COVER, WATER PUMP for 2004 Honda ST1300
19220-MCS-010

Save Changes
$196.13
Save to Wishlist
$196.13
Remove
Honda
GASKET, WATER PUMP for 2004 Honda ST1300
19226-MCS-000

Save Changes
$15.42
Save to Wishlist
$15.42
Remove
Honda
THERMOSTAT for 2004 Honda ST1300
19300-MBT-003

Save Changes
$37.87
Save to Wishlist
$37.87
Remove
Honda
HOSE, R. WATER for 2004 Honda ST1300
19504-MCS-010

Save Changes
$6.22
Save to Wishlist
$6.22
Remove
Honda
HOSE, L. WATER for 2004 Honda ST1300
19506-MCS-010

Save Changes
$6.22
Save to Wishlist
$6.22
Remove
Honda
CLAMP (22-29MM) for 2004 Honda ST1300
19517-ML7-691

Save Changes
$10.04
Save to Wishlist
$40.16
Remove
Honda
O-RING (43.5X2) for 2004 Honda ST1300
91361-SF4-951

Save Changes
$2.42
Save to Wishlist
$2.42
Remove
Honda
HOSE, RADIATOR for 2004 Honda ST1300
19501-MCS-G00

Save Changes
$18.80
Save to Wishlist
$18.80
Remove
Honda
HOSE, RADIATOR for 2004 Honda ST1300
19502-MCS-G00

Save Changes
$15.58
Save to Wishlist
$15.58
Remove
Honda
CLAMP (30-37MM) for 2004 Honda ST1300
19516-GAG-003

Save Changes
$12.48
Save to Wishlist
$49.92
Remove
Have coupon code? enter it here Add Coupon
Total:
$388.74

 

[SupraSabre]

Well, that would cause a major leak!

I had to get a replacement for the waterpump cover for my '05 replacement engine. I picked one up off ebay pretty cheap. I'm not sure if you can get parts off ebay shipped to you, but it might save you afew $$$.

Good luck!

 

[longerone]

Ok sabre, i will give it a shot.

 

[longerone]

Thank you for the positive input, i received the parts and fit them, flush and replaced the coolant with Honda type2 then went for a 750 miles ride. STill noticed a drip drop lick at idle, but nothing serious, i think its from one of the hose clamps. Temp remain at 3 bars solid.Thank God its not a more serious problem.