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bit lost with the pcv deal
robertst - 18/7/07 at 02:57 PM

i've searced around and found the solution to crankcase ventilation on a pinto but dont really know how it works...

so, if i understood it correctly, you reroute the hose to a catch tank such as the one in the pic and that is supposed to get some of the oil right?

where does the outlet hose go to? there are two connections in the tank...

also wouldnt there always be a problem with oil level in the engine, needing frequent topping-up?? and also frequent emptying of the catch tank?

thanks Rescued attachment Catch Tank.jpg
Rescued attachment Catch Tank.jpg


mookaloid - 18/7/07 at 03:12 PM

I have plumbed the catch tank back into the sump so it drains away automatically.

Some people have found that the catch tanks fill quite quickly and are not happy to put the oil back into the engine, so they use a lot of oil....

Take your pick

Cheers

mark


robertst - 18/7/07 at 03:32 PM

by plumbing the oil back to the sump makes me think about oil pressure...

where exactly is oil pressure acting? is it inside the oil galleries or inside the block itself?

im thinking of oil or air pressure shooting up from the return pipe into the catch tank?...

i read that there a blank tapped hole on 205 blocks that can be used to route the return pipe back to the block.. where can i get a screw with an outlet pipe from?


DarrenW - 18/7/07 at 03:35 PM

My tank is almost identical. This site indicates that a good design would have the inlets extending towards base of tank and a faom baffle adding which sounds a good idea. Im trying to get my head around a mod to mine.

Only thing i can see from most bought tanks is the outlet is same diameter as inlet. Im going to experiment with larger outlet.

http://members.aol.com/sarandrews/wateroil.htm

Std PCV needs to be modded if you route to catch tank. I have Cortina breather / trap fitted coutesy of Mark.

There is another thread running to discuss breathing.


DarrenW - 18/7/07 at 03:42 PM

205 blocks have oil gallery plugs - is this what you mean? Not sure if oil can be fed back into these but sounds decent idea. ive tapped my plug for the oil temp sender.

You can get air line connections with tapped ends and a convenient parbed pipe connection. Not sure if these will work or not.

Im trying to run crankcase piping as vertically as poss to stop oil being chucked up. I guess same theory for feed back to sump applies. Mark's seems to work well.

My only reservation is the oil in catch tank is always murky and brown but this may be due vaporisation of hot gasses hitting cold catch tank sides. Maybe if oil wasnt allowed to sit in then it wouldnt be as yucky. One theory is the water in the oil would be boiled off when engine is running and as there should never be a huge qty at any one point in time then again in theory there shouldnt be a big problem. It certainly works for Mark. I could test the theory by fitting a drain at bottom of my tank and running off into a bottle to see what happens (same as running into sump in a way as a test first).

[Edited on 18/7/07 by DarrenW]


robertst - 18/7/07 at 03:55 PM

cheers darren it does seem opinion is very divided w.r.t return pipes. i guess no ones had probelms with them yet...

the plug i'm talking about is located below the cooling drain plug on the left side.. i took it off yeaterday and wondered why it was there as its not part of an oil gallery it opens to the block and sump...

[edit:] as said many times here, some have experienced their catch tanks filling up quite quickly. for those that discard the oil it must be quite expensive to run their cars! a return would save having to top-up the level everytime you go out for a ride IMHO...

[Edited on 18/7/07 by robertst]


DarrenW - 18/7/07 at 03:59 PM

I cant think where that plug is. Might have to have a better look at mine tonight. By LHS is that as if you were sitting in the car - ie dipstick side? I recall using the cooling drain plug when i flushed the crud out of my old block so it must be that side. Could be interesting to use that as it is easier than taking sump off to mod it again.


robertst - 18/7/07 at 04:16 PM

quote:
Originally posted by DarrenW
I cant think where that plug is. Might have to have a better look at mine tonight. By LHS is that as if you were sitting in the car - ie dipstick side? I recall using the cooling drain plug when i flushed the crud out of my old block so it must be that side. Could be interesting to use that as it is easier than taking sump off to mod it again.


err no.. the dipstick is on the left hand side the cooling drain plug and the plug im talking about are on the right hand side and this plug is directly beneath the cooling drain plug.

i happen to be dismantling my engine so i took a few pics... i think its perfect for an oil return. goes straight into the sump

first one shows the two plugs, cooling and the numpty one.
possible oil return plug
possible oil return plug


this pic shows the hole
possible oil return plug
possible oil return plug


you can see in this one that the oil goes straight back down into the sump...
again
again


DarrenW - 18/7/07 at 09:53 PM

I see what you mean now. Your first post about plug said LHS which threw me a bit.

You may be onto something there. Sounds decent ide to me. I found out a threaded air line connector tonight, might see if it fits sometime. I have it in my head it will be 1/8" or 1/4" npt at a guess.

Feeding catch tank oil back to sump is great as long as you are sure it is only oil - this where opinion is divided. On mine im pretty sure it is mainly oil. Im running rich which explains the fuel smell. I think water vapour is condensing in the ali tank and as it has nowhere to go gets mixed up by car movement into an oil rich brown murky mess.


bimbleuk - 19/7/07 at 08:45 AM

You can get excessive oil vapour out the cam covers if there isn't sufficient baffling on the exit pipe. Might be worth looking at.


DarrenW - 19/7/07 at 09:26 AM

i decided to take the top off my catch tank last night. Inlet pipes are only short internally so ive now fitted an baffle plate. The theory here is that oil vapour will hit the back of the plate and encourage it to flow to bottom of the tank. Large opening then wont allow pressure to build up inside. I have the choice of fitting a drain or leave large hole ( i will probs cover this up and fit a more aesthetic pipe to hide the internals) and have to tip it out at periodic points.
Before mods, it was kind of OK when i keep it emptied, but once there is a build up it all got messy.

Baffle stops short of the base (not easy to see in pic). i cant use the plug in your pic as this is where i have fitted oil temp sender. On reflection maybe not the best location for the sender.

[Edited on 19/7/07 by DarrenW] Rescued attachment 19072007139.jpg
Rescued attachment 19072007139.jpg


DarrenW - 19/7/07 at 09:27 PM

Are there any other plugs in oil galleries that could be used to feed oil back in?

Mark - how does yours get back in - modified sump?? I dont want to take sump off to mod it - hence wondering about alternatives.


DarrenW - 20/7/07 at 02:22 PM

Ive removed oil temp sender and used the hole for drain back into sump. I robbed the end off my air ratchet - fits in the block great and has an airline connection that the pipe fits onto.

This hole was obviously a crap position for the oil temp sender. i might try and drill / tap the sump plug for the sender next. Anyone got a spare so i can try and mod it?