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ttubb
01-30-2014, 08:51 AM
My son, Justin (Taildragon) alerted me to a mod some of the folks back east have done to reduce deposits in the intake manifold and throttle body. It is a simple process involving cutting a hose and inserting a small filter in the line. I got all the parts from Harbor Freight for less than $11.
Parts -
2 ea 68211 barb fitting with clamps - $1.99 ea
1 ea 68225 Mini Air Filter - $6.49

The air filter is designed to be under pressure so you must block the drain port to prevent air from being sucked in. I did it with a small section of plastic hose with a rivit inserted in the end.

The interesting thing is that after a day of wheeling, I had over a quarter of an inch of oil in that bowl.

Simple fix, works great! Terry

baja1d
01-30-2014, 08:57 AM
Which engine is this for?

ttubb
01-30-2014, 09:03 AM
Which engine is this for?


Sorry, this is on a 95 FZJ-80. T

Corbet
01-30-2014, 05:19 PM
seems like if you had that much oil in there you would have had a series consumption issue prior?

ttubb
01-30-2014, 06:42 PM
seems like if you had that much oil in there you would have had a series consumption issue prior?

Nope. This just captures the oil that would normally be vaporized and sucked into the intake system. The tube is there from the factory, the filter/bowl just recaptures it.

Inukshuk
01-30-2014, 09:46 PM
seems like if you had that much oil in there you would have had a series consumption issue prior?

x2

Corbet
01-30-2014, 10:32 PM
Yah, but if that much oil got vaporized all the time you'd be a quart low in no time?

ttubb
01-31-2014, 06:55 AM
Yah, but if that much oil got vaporized all the time you'd be a quart low in no time?

You are forgetting this line is open from the factory. The filter and bowl only recapture vaporized oil so it does not go into the intake. It does not increase oil consumption.

DaveInDenver
01-31-2014, 07:13 AM
You are forgetting this line is open from the factory. The filter and bowl only recapture vaporized oil so it does not go into the intake. It does not increase oil consumption.
It's not that it's increasing consumption but that if you have that much oil being vaporized then you have something causing it in the first place. That seems like a lot of oil to burn up in the course of a day. If I lost that much oil daily in my 22R I'd have none in the crankcase after a month.

J Kimmel
01-31-2014, 07:44 AM
this mod doesn't increase consumption but if your engine is vaporizing that much oil to begin with you might have a consumption problem :)

baja1d
01-31-2014, 07:46 AM
So what would be the cause. I'm confident that I'd fill the bowl on mine. Is there a mod for the bowl back to crank case???

ttubb
01-31-2014, 08:24 AM
this mod doesn't increase consumption but if your engine is vaporizing that much oil to begin with you might have a consumption problem :)

Exactly. :beer: :beer:

ttubb
01-31-2014, 09:17 AM
"The article below give a good overview of the system and reason to have it. My main reason for the install is to avoid the common 80 series EGR failure down the road. Time will be the judge of that." Landcruiser Phil - Copperstate Cruisers

PCV System Oil and Air Separator

The crankcase in a car is used as a storage place for oil, usually in a pan located below the crankshaft. While the crankshaft and the oil aren't intended to come into contact (because if they did the oil would get frothed up like a thick, black milkshake), oil vapors can still find their way into the blow-by gases. It's not a good idea for these oil vapors to be recirculated back into the cylinders along with the blow-by gases because they make the gas-air mixture too combustible, equivalent to lowering the octane of the gasoline, which in some engines can degrade performance slightly and in older engines can even cause backfire when the gas-air mixture combusts prematurely. The oil vapors can also coat the air intake with an oily film, gradually clogging the air flow over time. If you don't drive a high performance vehicle, these problems aren't exactly crucial to your car's operation and the oil build-up can be scrubbed out periodically during maintenance, but some people (and some car manufacturers) prefer to have something that will scrub the oil out of the blow-by gases before they're recirculated in the first place. Enter the oil and air separator.

The idea of an oil and air separator is to extract the oil from the air before it's sent back to the intake manifold and put it someplace where it won't cause a problem, either back in the crankcase or in a small receptacle called a catch can. Not all cars come with built-in oil separators and not all cars necessarily need them, but they can be purchased as aftermarket items. And if you have the necessary DIY skills, you can even make one yourself. There are actually a number of different ways in which these oil and air separators can work. Probably the most common kind blows the oily air through a mesh filter. The oil droplets are trapped in the mesh while the air passes through. The most effective such filters are made up of microfibers, which can trap very small particles of oil. Alternatively, the air and oil filter may require the recycled gases to go down a tube with holes in its side. The lighter air molecules escape through the holes, while the heavier oil droplets fall all the way to the bottom, where they can be removed. And some advanced systems use a centrifuge to drive the heavier oil droplets out of the air. The oil coalesces on the sides of the centrifuge and can be channeled back into the crankcase.

As an aside, all piston aircraft engines have these in use. Terry

DaveInDenver
01-31-2014, 09:31 AM
I don't think anyone questions the usefulness of it, just how much is coming out. Maybe I'm missing something. I took my throttle body and intake apart at 187,000 miles and there was a a little gummy varnish at the very end near #4 from the crankcase ventilation but not so much that I thought I needed to install an oil separator. The back of my TB throat plate gets a little sticky after a few years, but not excessive. Now I do rotate PCVs every oil change, one on deck sitting in solvent while the other is in the valve cover, which may have something to do with it.

baja1d
01-31-2014, 03:15 PM
Side note PM sent

OilHammer
01-31-2014, 04:28 PM
It's mostly condensation slime that catches in those filters. The 80 series guys have been doing this on mud for some time. Yeah, some oil does collect there, but most of the guys that post pictures show some light brown sludge in it that they dump at each fill up.

74fj40
02-02-2014, 06:21 AM
For what it's worth, Toyotas oil consumption specification is 1 quart of oil per 1200 miles of driving.

Inukshuk
02-02-2014, 10:57 AM
For what it's worth, Toyotas oil consumption specification is 1 quart of oil per 1200 miles of driving.

In my Robbie Rebuilt 1FZFE (with an untouched 195,000 mile short block) I have ZERO consumption of Mobil 1. I'm getting lazy about checking oil. Better do that today.

PabloCruise
02-11-2014, 01:37 PM
I hear the 3FE guys talking about this as the intake runner does get pretty nasty from the PCV being in the valve cover.
I have bought the seperator, but not installed it yet.

60wag
02-11-2014, 03:45 PM
Aren't all PCV valves in the valve cover?

subzali
02-11-2014, 05:57 PM
Not on a 2F

PabloCruise
02-12-2014, 12:31 PM
Not on a 2F

Right. Those come out the side of the valve train pushrod cover.

Apparently the top of 2F heads are much cleaner than the top of the 3FE heads due to this...

60wag
02-12-2014, 03:01 PM
I should have remembered that. My last 2F is becoming a distant memory. All of my current engines have the valve stuck in the valve cover.

If the flow of the PCV system is out the PVC valve to the intake manifold, why would the top of the head be any cleaner with the valve in the side cover? It's not like there isn't a bunch of oil already up there. I can see how there might be oil crud building up in the intake manifold.