RZV500 - Oil in coolant

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wheels999
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RZV500 - Oil in coolant

Post by wheels999 »

Took the rear head off the engine on the long weekend and found the head look fine. No signs of a blown gasket.

Still have to take the front head off (next weekend).

Is there any way, other than via the head gaskets, that oil could get into the coolant system? Gearbox?

I'm starting to suspect the oil may have been nothing more than someone accidentally refilling with two stroke oil on the wrong side (into the coolant resvervoir). Will have a good look at that on the weend.

Cheers, markus.
hybrid
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Re: RZV500 - Oil in coolant

Post by hybrid »

There is a seal between the gearbox and water pump, but generally that lets water into the gearbox oil and not the other way around, due to the water being under pressure when hot.

How much oil was actually in there?
RD350LC- RGV Mods, PWK28's
RZ500 - YZR Replica, PWK28's
wheels999
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Re: RZV500 - Oil in coolant

Post by wheels999 »

hybrid wrote:There is a seal between the gearbox and water pump, but generally that lets water into the gearbox oil and not the other way around, due to the water being under pressure when hot.

How much oil was actually in there?
So far I've sponged up about 2 table spoons worth out top of the radiator.... the weird thing was, oil of similar consistency was running down the the fork legs when the bike came out of the container.... I thought it may have been a forkseal... but they're not leaking as far as I can tell.

I'll have to check the gearbox oil levels next time I work on the bike as well...

Cheers, Markus.
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HM31A
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Re: RZV500 - Oil in coolant

Post by HM31A »

is the g/box oil pressure higher than the cooling system pressure to make the transfer across
being a 2t i wouldnt of thought a h/gasket problem but i ant no expert on these thats all
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Re: RZV500 - Oil in coolant

Post by hybrid »

No the gearbox pressure shouldn't be higher.. it shoud be vented, so really should be at atmosphere, but aside from the headgasket, that's really the only possibility I would think.
You would definitely have milky oil in the gearbox if it was the water pump seal.
RD350LC- RGV Mods, PWK28's
RZ500 - YZR Replica, PWK28's
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