Oil leak under engine

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oldjapanesebikes
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Re: Oil leak under engine

Post by oldjapanesebikes »

pennell wrote:Also, once the water pump does anyone know the part numbers that I need? And if they are still available at the dealer?
Suzuki still sells the pumps - part number is 17400-31830 which buys you the complete unit. You can also still buy some water pump components from Suzuki. Just check any of the on-line fiches for the part numbers ( I use http://www.powersportspro.com" onclick="window.open(this.href);return false; but there are many). It also helps to go to your dealer with a list of the part numbers as some of the parts counter jocks are too damn lazy to look up stuff for old bikes :? Full rebuild kits are also available overseas in the UK from Crooks Suzuki and Germany from Reiner if you want to go that route. Bottom line - the parts are not a problem - lots of options 8)
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RING_DING
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Re: Oil leak under engine

Post by RING_DING »

So I also have the oil drip problem. Reading through this thread I have a question though. An earlier post indicates that the breather vents the space between the oil seal and the mechanical seal.

"The air breather pipe (#14) in the waterpump diagram vents the space between the two seals. That space is vented to the atmosphere to allow for expansion/contraction of the water pump as the engine heats up and cools down. If one of the seals fail, either the oil seal or the mechanical seal, the breather pipe allows the fluid to escape before it can cross contaminate the other fluid."

However, a later post indicates that it vents the space between the two o-rings.

"The breather line goes to an air space in the waterpump housing and is essentially a vent for pressure differences caused by the water pump metal heating and expanding inside the engine. There is an O-ring on either side of the air space, one stops oil and the other stops coolant."


Can someone confirm which is correct, or have I misinterpreted somewhere? Thanks!
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oldjapanesebikes
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Re: Oil leak under engine

Post by oldjapanesebikes »

Image

Sometimes a photo helps (even if it is too large :? ) - second from left lower row is the crankcase side oil seal, third from left is the removable water pump body - note the two o-rings, fourth, fifth, six and seventh from left are the components of the water side seal. The vent exits from the water pump body between the two o-rings. 8)
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RING_DING
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Re: Oil leak under engine

Post by RING_DING »

Thanks Ian, this helps a lot. So just replacing the two o-rings ought to cure the leak then?
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oldjapanesebikes
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Re: Oil leak under engine

Post by oldjapanesebikes »

RING_DING wrote:Thanks Ian, this helps a lot. So just replacing the two o-rings ought to cure the leak then?
Probably not - oil typically first has to pass by the oil seal (second from left in the photo) before it sees the area bounded by the o-rings as the wear point is the rotary shaft, not the pump housing. The seal is a 10x22x8 which you can pick up at most industrial bearing and seal supply places for around $1.
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tz375
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Re: Oil leak under engine

Post by tz375 »

And if the shaft is word, the seal replacement alone may not be enough to fix it. I can't get those seals for $1 but they are not very expensive and they are available from bearing/seal suppliers such as Berry Bearings/ Motion Inductries
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Re: Oil leak under engine

Post by oldjapanesebikes »

tz375 wrote:And if the shaft is worn, the seal replacement alone may not be enough to fix it.
True 8)
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Re: Oil leak under engine

Post by Suzukidave »

And then on top of fixing the pump seals is sometimes just getting the pump out of the engine can turn into a good challenge :roll:
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tz375
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Re: Oil leak under engine

Post by tz375 »

I have only done a couple and it was after the motor was rebuilt, so they came out reasonably easily. My technique is to remove the fuel tank and center pipes gently lower the big girl down on her side. remove the pump cover (should have mentioned - drain water/coolant first). Remove the circlip and impeller and then gently but firmly pull the pump out. It needs to be pulled with a puller or carefully levered out but be careful you don't damage the engine cases.

Back to an earlier question. The vent goes to the space between the O rings and the pump housing is cross drilled to connect to the gap between the oil seal and the mechanical seal.

Oil dripping out has probably passed the oil seal and water dripping comes past the mechanical seal. The problme could be torn seal, worn seal or corroded or grooved shaft.

Mechanical seals are similar to Type 21 seals but are retained in the housing and not on the shaft. They consist of a carbon (graphite) face onto of a spring and case. The seal face is a stainless steel component that is sealed against the shaft by a tiny O ring. Graphite cracks and chips over time and stainless steel faces get grooves and other damage.

Modes of failure Fix
Shafts wear and corrode Weld shaft and grind it back to size.
Oil seal leaks Remove pump, strip and replace seal.
Mechanical seal cracks Remove and strip pump, replace seal.
Replacement seals leak Teflon seals in repair kits do not always work
Stainless steel mechanical seal seat worn Reface face/machine a new one
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Re: Oil leak under engine

Post by Suzukidave »

Image
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Re: Oil leak under engine

Post by Suzukidave »

tz375 wrote:I have only done a couple and it was after the motor was rebuilt, so they came out reasonably easily. My technique is to remove the fuel tank and center pipes gently lower the big girl down on her side. remove the pump cover (should have mentioned - drain water/coolant first). Remove the circlip and impeller and then gently but firmly pull the pump out. It needs to be pulled with a puller or carefully levered out but be careful you don't damage the engine cases.
And if all else fails before you bugger up the pump or your cases viewtopic.php?f=9&t=1956" onclick="window.open(this.href);return false;
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Re: Oil leak under engine

Post by wrenchbender »

Interesting....... I recently bought a GT750A from a road racer friend in FL. He had lost interest after he paid someone to paint it and the color was wrong. The bike had been sitting in the back of his warehouse for several years. When I got it home and running it was leaking oil from the water pump weep hole. An internet search led me to this forum. I read where philip44 gave up and sold the bike. His bike was painted Black and He included 2 new tires and throttle cables. My bike was Black before the wrong color repaint and my friend gave me 2 tires and throttle cables he got with it. AH HA.....Several years later a new owner is researching the same problem on the same bike that started this thread !! Small world!
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Suzukidave
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Re: Oil leak under engine

Post by Suzukidave »

Well ... looks like your turn to fix the leak :up: welcome to the group BTW :D
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