1st gen 3.4 oil catch can install

I could see EGR be considered feeding your engine its own shit, but PCV flow should be fairly clean oil assuming you keep up on maintenance.

And you shouldnt have much/ any oil on your intake valves on a port injected engine. The fuel sprays onto the valve and should keep it clean. Haven't dove that far into a 3.4 so i say "should"

 

i doubt 13+ year injectors are atomizing nicely..

 

And yes I know, Motorcycle engines are different but these things have 2 injectors PER cyl.. This is before and after on a 2010 CBR 1kRR, All 8 intake valves looked like this one.

 

How did you remove the carbon build up?
This was a giant issue with the Audi RS4 insomuch that if you were attempting to sell one, the first question out of the buyers mouth was "did you service the carbon buildup issue?"

 

Wire wheel, Most bikes have Ti valves with a special coating and wire wheel is safe to use for clean up (in moderation).

 

These valves are Ti with special coating and one cleaned (WireWheel), one fresh from the motor.

 

Flow through the PCV valve is anything but clean. Suspended particulates, fuel blow-by, and water that has condensed out of the air/fuel/oil are all present. While the intake valves may stay clean due to direct port injection (I have nothing to prove or disprove this), the throttle body, intake runners, head chamber, and top of piston all end up with these byproducts depositing on them.

 

I had one on my 3.4 since new and I get maybe a teaspoon out of the catch can per oil change and that's every 3-4 thousand miles and also helps keep throttle body clean, I think its well worth the time and money.... and its a 99 4 runner with 3.4 with 191000 miles. Also have a 92 Toyota truck with 2.4 with one also and it has 268000 miles on it. get about the same out of it on oil changes (just my 2 cents worth)

 

Yep, well said. "Combustion byproducts" has a nice dirty sound to it.

The 3.4 in good shape is not known to consume much oil compared to the 2.7 or the 4.0. That being said, 100% of the crud found in the t-body and IAC valve comes from the PCV system. Just how much oil/crud gets caught in a given engine is affected by many variables. Engine condition and operating conditions are big ones. One does not have to look very far in the second gen 4.0 thread
http://www.tacomaworld.com/forum/2nd-gen-tacomas/231227-oil-catch-can-install-guide.html
to see how much oil/crud those guys are catching in fairly new engines, NA or forced. It varies too, sometimes relatively clean oil other times pretty nasty stuff. See "variables" above. 1st gen 2.7 folks seem to catch way more stuff than 3.4 folks.

I put a can on my NA 3.4 almost 3 years ago as an experiment with another "oil" theory.
https://www.tacomaworld.com/threads/3-4-oil-catch-can.351301/
Since those observations I have on occasion collected more oil under certain conditions. Thick smelly black awful stuff. Typically sustained higher RPM/high engine load situations like climbing the Rocky Mountains with a load of gear. Still nothing like the second gen folks but more than the "nothing" collected during more average driving. The notable thing is how the t-body stays cleaner. Just look at where the PCV vacuum port is located. It's about as close as it could get to the throttle plate. Then note where the inlet for the IAC valve is. Don't assume the intake air only flows in one direction and take a second here to think about why the t-body gasket is "D" shaped with the flat side directly in front of the PCV port.

I have another pet theory about the 3.4 PCV system. That is it's borderline capable of keeping up with the volume of blow by gasses under some conditions. Many folks report finding the "fresh air" inlet hose wet with oil. It seems Toyota was aware of this and used a larger hose with a catch can of sorts on later years. Also it seems the PCV valve itself can get fouled a bit and under perform while still passing the old shake/blow/suck tests. Then there is the relatively small ID of the PVC hose itself. Add some build up/swelling and restriction can occur. In the old days a faulty PCV valve would frequently cause a change in idle speed. With computer controlled idle the ECU just compensates for any increase/decrease of air entering the intake from a failing valve so they get overlooked.

I don't buy the "port injection cleans valves" thing. There certainly could be some small cleaning effect but the oil/crud is still going somewhere and fuel in itself can leave residue. Heck, I go back to the days of performance carbs with accelerator pumps of 50cc or more. That's one mean squirt of raw liquid fuel.

So when it comes down to it, a catch can on a NA 3.4 is by no means a cut and dry universal yes or no.

 

Ahh, always wondered why the TB gasket was D shaped. Makes total sense. Also why a catch can is necessary for forced induction - the SC install kit has you replace that D gasket with a round one.

 

Yep again. The blower does a pretty fair job of "mixing up" the intake air/PCV slop. Years ago there was a brief flurry of folks with NA 3.4's swapping out OE "D" for the blower gasket thinking they were going to see some increased airflow benefit. All they did was concentrate the PCV crud to the front intake runners/cylinders.

 

Great writeup thanks!

 

How did you run your oil catch can? Is it the same way the OP routed his? Im SC and considering doing this mod.

 

I ran the PCV valve hose to the input of the CC and the outlet hose from my CC to the PCV port on the SC.

 

Oh. And the liquid caught in the catch can is nasty stuff. Oil & fuel. Not something I want to send through the rotors...

 

A methanol kit will pretty much eliminate carbon buildup on valves, throttle body and rotors, here is a photo of rotors with
100,000 miles with no carbon build up from the last rebuild and almost zero
Carbon on valves

 

My thinking is : Aircraft engines do not use PCV systems. why would you want oil vapor sucked into your intake where it will dilute the fuel, contaminate and slow the combustion process, and leave carbon build up on your valve stems, piston tops and dramatically reduce the efficiency of your engine. Federal law mandated you could no longer, simply vent your crankcase to atmosphere. some where around 1963 PCV valves went into general use as one of the first emission devices, put has not been improved on, oil vapor "Catch Cans" are a step in the right direction, and can extend the life expectation of an engine.

 

Technically speaking you could just vent to atmosphere and just reattach the tube when you go to get emissions done

 

la manguera que esta conectada inicialmente , tenia una billa de acero en el lado del conector del intake?

 

Translation

Did the hose that was initially connected have a steel rod on the side of the intake connector?