Crank case moisture

[Super73]

I recently tore my 418 LS motor down and made some changes. One big change is I am on E85.

Pistons are set with .0045 clearance and rings are gapped 28/32 as I am intending on spraying it down with 300-400hp on n20.

I have also installed a vacuum pump with catch can.

The tune was fairly rich up until now, I have aprox 50-75miles on it getting part throttle leaned out and working in to WOT. When first driving I was collecting a lot of moisture in the catch can, as much as 3oz with in 6-8 miles. That has now been reduced to roughly 1oz in roughly 15 miles.

I pulled the oil filler cap off tonight and there is a good amount of foam collected in the cap and filler neck.

My vacuum pump pulls from a modified LS3 valley cover using a -12 line to the pump but there is nothing tieng to to the valve covers which are technically the highest point. I think the moisture is collecting there for that very reason.

Thinking about hooking the valve covers up the the pump as well but I am curious as to what others are doing.

Everything is sealed and I can only attribute the moisture to the fuel and blowby.

Thought, ideas and suggestions are definately wanted.
Posted via Mobile Device

[cdowns]

the auto manufacturers stole a design from worlwar 2 tanks a virtualyl trouble free system to remove moisture and prevent sluge they called it a PCV system

[slowtruck]

I don't think that's going to help him and a vac pump will do more than even the best PCV system ever made.

[vin63]

You should see my oil after a pass - pretty much tapioca pudding. Back to your issue, there are probably a few things going on aside from alcohol being hydroscopic as I'm sure you're keenly aware. Running rich on an alcohol tune will significantly contribute to moisture in the crankcase, in addition to the wide temp variations in the heat cycles that causes condensation. This last point is why the TBN rating on modern oils is so important to combat the internal corrosion from moisture/condensation in the crankcase. I would try attaching your vacuum pump to a valve cover to see if that helps.

[Marv D]

Gotta agree with that Shaun. When you pull down a motor that has been accumilating water from a weeping head bolt or cracked casting.... where do you see the milky accumilation! I know in yesteryear motors we had metal intakes / valley covers (where your plastic?) and maybe the heat-soak of the aluminum/iron cast intake cooked moisture away better,,,,,, but the 'milk' was always in the rocker covers,,,, the highest point.

I sure can see your delimma in finding a place to put a fitting into the stock LS rocker covers.

But just a thought here. My LS sandrail motor has a (for lack of better terms) steam bleed-tube running between the heads because we have no water cross over up high on the LS. I can't help but believe we have a similar 'lack of flow' in crankcase vapors traped up high in the motor also. Pulling vapors 'down' from one rocker cover, through the crankcase,, then up and out the other rocker cover.... Well you see where I'm headed there. Some sort of cross-connection between the rocker covers might be worth investigating for you alky guys??? It would still create negative pressure in the entire motor, but evacuate the top end first.
Just a thought