Small Intermittent Coolant Leak

[91nwl]

91 Venture Royale, 43,000 miles.

 

When I ride all day in hot weather, the next morning I have a little bit of coolant on my right exhaust just below the water pump. It burns off when I start up and the loss is negligable. Still It bugs me. I thought it was the o-rings in the plastic transfer pipe between the water pump and the thermostat housing.

 

But, today I got down and looked and there is a little hole in the bottom of the water pump and there is a stain, as though coolant has leaked out the hole from time to time. This is the only place that looks like anything has leaked in the past.

 

Anyone have a similar experience? Do I need to fix it?

[shighley]

91nwl;

My '83 TK, 99K miles showed the exact symptoms your describe. I ordered all the seals, gaskets and O rings required and rebuilt the pump unit. The amount of "weep" or film deposited on the housing, at the drain hole, is 10 times less, but it's still there. The sealing mechanisim is very interesting to me as I'm not a pro mechanic. The impeller to housing seal is made up of a spring loaded neoprene sleeve that is held against a flat disc pressed into the impeller. I don't understand how the arrangement can possible work (again I'm not a pro)! I'm guessing a little weeping is normal and to tell you the truth, I think I wasted my time and limited talent! I'm very interested to hear what the real wrenches say on this subject. I was suprised to find a plastic impeller in mine that was still hanging in there at almost 100K miles. Ride safe, Steve

[91nwl]

So, doesn't anyone know if that little hole in the bottom of the water pump is supposed to leak or not? Is it a bypass, like on a car water pump?

[Eck]

Well, I would love to help answer this question you have, but I truely do not know the answer and I will not just throw out a wild GUESS to you..

The only thing I can offer to help you is to suggest you call or stop by your local dealer and ask the service manager ...or one of the mechanics.

You might even take time to call a couple differnet dealers (at random) to get a selection of answers or to see if they are all the same..

I would like to know ..

[Condor]

Up in Susanville at VWIII we had a couple of scoots that this happened to. Mine included, and it's had never happened before...or since. Seems to happen during a cold night when the motor cools down, and it's quite common. Start it up and it goes away. Fred gave a technical explanation on it, and it wasn't something to be super concerned about just as long as it was a small leak, and was intermitant.

[91nwl]

Up in Susanville at VWIII we had a couple of scoots that this happened to. Mine included, and it's had never happened before...or since. Seems to happen during a cold night when the motor cools down, and it's quite common. Start it up and it goes away. Fred gave a technical explanation on it, and it wasn't something to be super concerned about just as long as it was a small leak, and was intermitant.

 

That's right. The typical scenario is hot day followed by cool night. The only time it is visible is in the morning. I've read here in the past that it may be that it leaks when hot, but evaporates on the pipe. Then, when the pipe cools down, it makes a little puddle.

[shighley]

91nwl and JustJack; Are we talking about two different leaks? The cool night thing sounds like the leak from the thermostat housing and I've also experienced it. I have the parts to rebuld the housing but haven't done it yet as it never leaked again. (Tempting fate?)

The water pump leak 91nwl posted about: I've been keeping an eye on it after the rebuilt and the weeping has totally stopped, clean as a whistle. My opinion on the purpose of the hole in the housing is to provide somewhere for coolant to go if/when it gets by the mechanical seal. If the hole wasn't there, it could force it way past the oil seal, through the ball bearing and into the crankcase. Milky oil anyone? I recommend you continue to watch the amount of weeping and when the quantity crosses your personal threshold for minor leaks, buy the parts and rebuild it. I'll post a list of parts if it will help you. Ride safe, Steve

[E-Fishin-C]

That's right. The typical scenario is hot day followed by cool night. The only time it is visible is in the morning. I've read here in the past that it may be that it leaks when hot, but evaporates on the pipe. Then, when the pipe cools down, it makes a little puddle.

 

Yup !!!!! your are correct on that

[91nwl]

91nwl and JustJack; Are we talking about two different leaks? The cool night thing sounds like the leak from the thermostat housing and I've also experienced it. I have the parts to rebuld the housing but haven't done it yet as it never leaked again. (Tempting fate?)

The water pump leak 91nwl posted about: I've been keeping an eye on it after the rebuilt and the weeping has totally stopped, clean as a whistle. My opinion on the purpose of the hole in the housing is to provide somewhere for coolant to go if/when it gets by the mechanical seal. If the hole wasn't there, it could force it way past the oil seal, through the ball bearing and into the crankcase. Milky oil anyone? I recommend you continue to watch the amount of weeping and when the quantity crosses your personal threshold for minor leaks, buy the parts and rebuild it. I'll post a list of parts if it will help you. Ride safe, Steve

 

Thanks

So, are you talking about a water pump rebuild?

[shighley]

91nwl; Yep, I'm offering a parts list to rebuild the water pump. The manual is a little funky as usual. It's not a difficult deal. If you decide to tackle the job, let us know.

BTW; the earlier post about the thermostat housing leak made me nervous again and I'm gonna do mine while on vacation in a couple of weeks. Best regards and ride safe, Steve

[Guest paru]

I just took a 1000 mile trip and have noticed that my waterpump seals have started to leak. I have found this old thread and wondered who has a part's list for the rebuild of the first gen waterpump.

[Guest littlestar]

I could be wrong, but that little hole in your water pump is a weep hole. It's supposed to be there, and occasionally coolant WILL leak out of it. I'm not sure why, but it is perfectly normal. This exact same thread came across the other venture riders website (venturers.org) and the experts there told someone with the same exact problem this very thing.

 

I think you're ok....

-Tim

[derwood]

Pretty old thread here, but the vent hole is between the bearing and the seal so the leaking coolant doesn't wash the bearing and find its way into the oil.

[Dano]

I'll do you one better. For a period of 3 weeks, anytime I rode, regardless off temp, mine leaked out the weep hole (yep, just like a car). Met with the guy from Buckeye Performance in Cincinnati one day while I was down there, he told me it's time to rebuild the pump. Then one day, it quit leaking, no water in oil, went on a 175 mi ride on Sunday and it didn't leak at all!!!! It will be rebuilt this winter when I do 2nd gear, but if it ain't broke, don't fix it!

Just my 2 cents worth,

Dan

[shighley]

Paru: I received your email and sent back an Excel file on the required parts. Let me know if you need more information. BTW, I could not reply through the Venture network to you, email denied! Good luck and let us know how the repairs go. Ride Safe, Steve

[Guest Vermincelli]

I was wondering if this was happening to mine. in the morning it's a puddle though under the radiator itself.

mine looks to be that little drain valve in front.

[shighley]

[ATTACH]12494[/ATTACH]

I don't know if the attachment process worked, so I'll cut and paste:

 

Page	Title	Ref. No.	Part Number	Superceded #	Description	Qty	Remarks
A-12	Water Pump	2	1FK-12450-00-00		Impeller Ass'y	1
A-12	Water Pump	6	93306-00004-00		Bearing,(B6000)	1	Pump shaft
A-12	Water Pump	7	93101-10090-00		Oil Seal	1	Pump shaft
A-12	Water Pump	8	11H-12438-00-00		Seal, Mechanical	1	Pump shaft
A-12	Water Pump	9	93211-16591-00		O Ring	1	Cover to Housing
A-12	Water Pump	14	26H-12449-00-00		Gasket, Water pump	1	Housing to C'Case
B-1	Water Pump	19	93210-27194-00		O Ring	2	For Joint

 

B-1		24	11H-12412-00-00		Seal, Thermostat	1
B-1		25	26H-12413-00-00		Cover, Thermostat	1	Tweaked!!!!!
B-1		26	93210-45511-00		O Ring	1	Thermo cover to housing
B-2	Radiator-Hose	1	26H-12578-00-00		HOSE 3	1	from T.stat hsg to rad.
B-2		23	93210-14104-00		O ring, Drain cock	1
B-2		24	26H-12566-01-00		PIPE, by pass	1
B-3	Radiator-Hose	26	90445-09252-00		HOSE	1	To overflow tank
B-3		28	26H-12576-01-00		HOSE 1	1
B-3		29	26H-12579-01-00		HOSE 4	1	from temp hsg to rad.
B-3		31	26H-12577-01-00		HOSE 2	1
B-3		34	26H-12427-00-00		GASKET, housing cover 1	1
B-3		37	26H-12428-00-00		GASKET, housing cover 2	1
B-3		44	26H-12589-00-00		HOSE 6	1
B-3		46	26H-12588-01-00		HOSE 5	1	from drain cock to rad.
B-3		47	90460-15227-00		Clamp, Hose 5	2	Too expensive!!

 

This looks pretty confusing if I do say so! Hope it helps someone, Steve

[Thom]

Pretty old thread here, but the vent hole is between the bearing and the seal so the leaking coolant doesn't wash the bearing and find its way into the oil.

 

but oil , water antifreeze make mud and plug up the hole , when i rebuilt mine , it was full and a mess to clean up .