PCV: Oil Separator Box Return Hose

[dl242gt]

I follow you. The 75 B20F had both the side of the block breather box and the oil filler cap breather.

Just an FYI, I tried the 74-75 tall oil filler cap on my setup and it didn't work well. It seemed to get too much oil trapped in the separator part of the cap. It would leak out and get all over the valve cover. I changed to the earlier type cap and it's worked fine on my wagon for years.

[84B23F]

Originally Posted by dl242gt

looks like..80s B23FT or B230FT pcv setup.

I suspect that setup was used in countries with "low emission requirements."

[84B23F]

Originally Posted by dl242gt

FYI, I tried the 74-75 tall oil filler cap on my setup and it didn't work well....changed to the earlier type cap and it's worked fine

I've got both caps (B18 & B20), but I find this "engineered" setup puzzling. Perhaps oil vapor condenses on filter and drains back into engine, unless old-faithful is blowing.

"Well K&N makes such a creature that fits the B18 and B20 engines, part # 62-1330. It fits perfectly on the oil filler cap."

[84B23F]

Dave - In this diagram at bottom, it shows the cap is suppose to suck air via fresh air intake

[dl242gt]

Yes, I know that setup well. I have also used the mini filter on mine to try it out when I had my 123GT. Mine on my 245 is doing the reverse by venting the fumes out of the valve cover and it works fine as an oil separator. Except for when I tried out the 74-75 tall cap. That one may only work for the fresh air in I guess.

[84B23F]

Originally Posted by dl242gt

Yes, I know that setup well.

If an engine's Oil-Separator-Box's Return-Hose was plugged in oil pan....I'd modify what VQ did here, and suck blow-by out of fuel pump port with a hose going vertically that has the flame trap kit hooked to it (flame guard, with vacuum hooked up), then hose it over to air intake hose....and plug PCV Oil Trap.

That flame guard is restricting total amount of blow-by...too much, and your AMM is under-seeing total air....and a new AMM won't make it run better.

thanks for tidbits.

[84B23F]

Originally Posted by dl242gt

Yes, I know that setup well.

Have you seen this setup? Just installed it today using a B18 valve cover cap, then a Ford PCV End Assembly (Dorman 46017), with vacuum hose inserted into PCV end assembly and taped with electrical tape. This 1990-240 is my "Sunday/Trip" driver, so I haven't tested it yet.

Engine is dripping oil at rear crank seal, so I'm reducing blow-by pressure to see if blowby is the reason why.

[PCH]

^^^ I believe with that setup there will be a lot of oil in the intake manifold. At the very least route it through the cheap $20 ebay catch can.
And also that vacuum fitting is too small for the blow by to pass through. For testing purposes only I would vent it into a plastic bottle just to see how much oil you're gonna get.

[84B23F]

Originally Posted by PCH

^^^ I believe with that setup there will be a lot of oil in the intake manifold..

Thanks for concern...several years back, this was done a different way, as can be seen in this picture on a 1993-245.

A semi-truck valve stem was used, and a plate riveted inside valve cover (prevent oil from splashing upwards, along with stainless steel scrubbing pad (Scotch Brite) inserted above plate, which is not seen. It has worked fine.

I'm just experimenting currently...I will be monitoring oil consumption. Engine is not an oil burner, and has plenty of power, but oil rings might be sludged a pinch. I'm just doing a quick test to rule out blow-by or not...if blow-by, I will re-ring engine..

[dl242gt]

If you check out the operation of the B18 pcv hose oil cap setup I was referring to. The direction of the gases at idle are to suck the fresh air into the engine from the pcv oil fill cap. However, at higher rpms above idle the fumes reverse direction and are pumped out through the cap into the air filter to be sucked into the engine.

The direction reversal of the gases is also used by Volvo with the stock B230F pcv setup.

[84B23F]

Originally Posted by dl242gt

...operation of the B18 pcv hose oil cap setup...

Without taking apart a B18 valve cover cap, I suspect its an open passage way without a flapper valve within. At least on a vintage cap

On B18 setup, intake suction was used at bottom of block, so yes, valve cover cap would be sucking filtered air until 'excess' blow-by existed, then it would blow blow-by into air filters' cavity.

RE: "...reversal..gases....stock B230F pcv setup."

If so, then a "vintage cap" may loose its flapper seal function, as in stuck closed on mine.

Just an experiment....either real crank seal is shot, or increased blow-by exist.

[84B23F]

Originally Posted by dl242gt

However, at higher rpms above idle the fumes reverse direction

Reversal is more of a function of intake vacuum...pedal to metal, and suction is much less than at idle...higher RPMs with a load (driving steady speed like 60 mph), less vacuum than at idle