What the hell is this nasty fluid?

john cervini /
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Having some issues with tuning. Pulled the head and found this nastiness inside. I initially thought water but my gas is clean. Any ideas?

Re: What the hell is this nasty fluid?

kinda looks like water that has been in a really hot place with oil.

post a pic of your spark-plug end

if could be something else, but id start by checking the fuel system for water. Gasoline is lighter than water, so the water will be at the very bottom of the gas tank and may require some serious jostling to get it out. or empty tank and somehow use a fan and/or heat gun(hair dryer) to aid evaporation. you may also find water in the bottom of your float-bowl or even in the fuel filter. (edited)

Re: What the hell is this nasty fluid?

john cervini /
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Here's the plug, this is the second tank of gas. Haven't seen any water yet.

Re: What the hell is this nasty fluid?

> Full Tuck Wrote:

> -------------------------------------------------------

> kinda looks like water that has been in a really hot place with oil.

>.

Could have gotten bad gas. Does it sit outside? Definitely looks like water. I would pull petcock drain everything clean kit and run it.

Also water will sit at the bottom so you won’t see it. Water is denser then gas so gravity will pull it to the bottom of the tank. You have to drain the whole thing. (edited)

Re: What the hell is this nasty fluid?

Ethanol can hold a certain amount of water without seperating.

Re: What the hell is this nasty fluid?

Stefan Josheski /

Chocolate milk

Re: What the hell is this nasty fluid?

john cervini /

Thanks everyone. I found a head and base gasket leak. It was 80% humidity yesterday and I'm thinking I sucked moisture in.

Re: What the hell is this nasty fluid?

This might sound weird but I've seen that kind of milkshake liquid in cylinders that the rings have gone bad in before, not sure why, might be correlation, but I've seen it multiple times, with cast iron cylinders. So maybe check the ring rap and make sure they didn't get really big all the sudden.

Re: What the hell is this nasty fluid?

Transmission fluid?

Re: What the hell is this nasty fluid?

That's a lot to be just water mixed in with the gas, unless it sat in the rain for awhile.

Could be a blown seal, and sucking the trans oil into the cylinder.

Re: What the hell is this nasty fluid?

Richard Eberline /

Your ethanol gas absorbs water thru a open part on your gas can.

Re: What the hell is this nasty fluid?

Dirty30 Dillon /

Yeah, that's not ethanol lol. Unless you poured 12 oz of Poland Springs into the tank

Re: What the hell is this nasty fluid?

Alan Jackson /

i once started my rd350 up and rode it only for a very short distance and switched off and took heads off to find EXACTLY the same as your pics. watery milky oily fluid everywhere as if i had a leaking head gasket on a water cooled motor.

cept mine was air cooled. so i just assume this is what happens when you start up and dont get engine to full operating temp before stripping down.

ethanol absorbs water so if its been stood in the tank a while you would get more of that fluid.

to be certain why not try tasting it?

Re: What the hell is this nasty fluid?

john cervini /

Thanks guys. I only run non ethanol gas in everything. It was definitely sucking moisture through the top end leaks.

Re: What the hell is this nasty fluid?

Alan Jackson /

water is a product of the combustion process and usually disappears when the motor gets hot.

you followed a car and seen the water dripping out of the exhaust?

the gasket leaks wont have contributed to water being sucked in, just made your fuel mix weaker.

higher humidity in the air maybe makes for more water production in the combustion process?

either way i wouldnt worry unless you still get that "fluid" after a run where the motor gets hot.

Re: What the hell is this nasty fluid?

john cervini /

It turns out that the transmission side seal is blown. Fresh rebuild so I'm surprised but shit happens

Re: What the hell is this nasty fluid?

yeah but what if it turns out it's water in the gas from the ethanol

Re: What the hell is this nasty fluid?

> jumpsuit steve Wrote:

> -------------------------------------------------------

> yeah but what if it turns out it's water in the gas from the ethanol

You can't cross a bridge , until you get to it . ;)

Re: What the hell is this nasty fluid?

I was thinking transmission seal myself . What can cause the new seal to fail? It’s in a bath of lubricant?

Re: What the hell is this nasty fluid?

john cervini /

I would love to know why the new seal failed as well. I ordered a new crank, bearings and seals just in case there's an issue with the crank

Re: What the hell is this nasty fluid?

My first thought on seeing that is that you've got a trans seal leak. a new seal will leak if you accidentally pop the retaining spring loose from it's groove while installing, which is a very easy thing to do. Then the whipped up and wetted transfluid makes a creamy looking yuck in the cylinder. Likt that's too much oil to be just from the gas/oil

Re: What the hell is this nasty fluid?

Seals can also not seat right when the crank is pushed through. The inner lip can turn inside out.

Re: What the hell is this nasty fluid?

Totally normal JBOT /

Always pack some Grease into the back side of the lip on the seal where the spring is that will keep it from jumping out when you tap the seal in place.

Or you can just remove the spring and have the same problem

Re: What the hell is this nasty fluid?

Totally normal JBOT /

> Justin La Plante Wrote:

> -------------------------------------------------------

> > Fake Crazy Wayne is a made up name Wrote:

>

> > -------------------------------------------------------

>

> > Always pack some Grease into the back side of the lip on the seal

> where

>

> > the spring is that will keep it from jumping out when you tap the seal

>

> > in place.

>

> >

>

> > Or you can just remove the spring and have the same problem

>

> Don’t pack grease into the seal or it will come out under load, You have

> no idea what you’re doing. When working on full sized bikes that’s a big

> no-no, and trucks even more.

>

> I never lube the seals on my sterling engine, I just use a drop of

> spittle and tap it in

>

> This isn’t nuclear physics here

My seals didn't leak after I put them in.

And I don't think that's spittle in your crankcase & cylinder there looks more like somebody rolled a few out into your gas tank.

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