DarrenW
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posted on 28/9/07 at 09:54 PM |
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quote: Originally posted by nitram38
Just get rid of the drain and try it with the pipe from the filler cap (I am assuming that you have this) and one from the side of the block.
I would even get rid of the Cortina trap as it could be causing a blockage.
I sounds to me that your system is getting pressurized and that is forcing oil into the tank.
As the drain level is in this oil, it is then blowing it out of the tank.
If you do all of this and you are still getting oil thrown out, then do a compression test on your cylinders.
Too much pressure could be your rings are worn and you are getting excessive blow-by.
Pablo, lift the pipes off the bottom of the catch tank and then you shouldn't get any oil out of the dipstick.
If the pipes are touching the bottom, they are not breathing and it is pressurising your crankcase
[Edited on 28/9/2007 by nitram38]
Ive just tried to edit your post rather than quote it - doh!!!! Why o why do i lose the text when i do that!!!!!!
I think you are on to something here - hence why im exploring it further, hope i dont come across as obstructive
im happy to try without drain again.
So you idea is remove cortine trap and fit pipe direct to block.
My supposedly drian point is actually a breather when driving hard so i guess i could feed this to top of tank as well = 2 crankcase breather
pipes.
Rocker cover is totally std. Oil filler cap is also std sierra, has mesh inside and outlet pipe which i have fed to catch tank. Dave andrews site
claims this should be sealed off - not sure why
Old engine did the same - it was high mleage so i expected it to a point. This block is only approx 45K miles. Strange that both do the same which is
why im convinced ive done something wrong. Am i really the only person to have these issues? Maybe im just too picky and should accept the oil slicks
in garage as just one of those things
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2b_pablo
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posted on 29/9/07 at 08:06 AM |
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Im using 15mm pipe too, darren are you using 10mm? might be worth beefing up the pipes.
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DarrenW
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posted on 1/10/07 at 08:27 AM |
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Sounds like some good ideas. Im using 1/2" bore rubber hose but the catch tank inlets are maybe only 10.5mm ID. Im now looking for a new temp
bottle where i can bring the pipes in from the top (cable tied to control the depth). From the crankcase i can bring 2 pipes in - one from std
crankcase breather hole and the other from the oil gallery plug that i did try and use as the drain back (unsuccessfully). I may also try and get a
new oil filler cap in case the mexh in mine is a bit crudded up (or at least clean it out).
Thanks for the suggestions.
At one point i have just had the smelly broth of foul liquid in there (early days) but now it is defo good oil being chucked up. Good oil coincides
with changing from restricted Sierra std breather to more open design. Maybe its not open enough.
Ive had same experience with cheapo K&N copy breather filter as well - partly why i removed it and cut top off the tank for a while as an
experiment. I still think most of my problems are currently the drain pipe back pressuring and splattering the oil in the can.
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DarrenW
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posted on 2/10/07 at 11:33 AM |
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Ok, ive just done a trial and now im well confused!
I found 2 translucent tubes. Both just under 0.5 litres. i havent altered any tubing as i wanted to see what was having the most effect (ie crankcase
or rocker cover). Tube / rubber pipe is 1/2" bore.
Piped one from cortina crankcase breather (that is fitted directly to block), pipe ran vertical and then into the tube about 1/2 way down.
Ran pipe from oil filler cap into second tube, again in about 1/2 way down. This leaves 1/4 litre capacity in each tube. Top of tubes are about level
with bottom of rocker cover (touch higher).
I also left the modified oil gallery plug connected to bottom of existing catch tank as a second brankcase breather.
Done a very short run (1 mile max) but driving hard through revs. Nothing in the oil filler cap tube. Crankcase tube full to bottom of pipe and
splattered all over. Catch tank also has oil in (ie from second crankcase breather).
What on earth is going on???????? As i said before i dont suspect a problem with engine as oil pressure indicated on DD2 display is around 70psi hot
and this is the second engine to do this (i could understand that the first could be worn but second engine has done less than 50K so should be
better). Engine is from E reg injected Granada and was destined for a mint Mk2 Escort, bought from a very reputable person (Mike in Bowburn).
Im fast running out of ideas.
Basically for the trial i havent changed anything other than 3 seperate tanks to see what is happening.
Would removing the cortina trap help or would this give easier path for oil to be thrown out?
Would capping off the second breather (ie gallery plug) help, is it possible air could be getting pulled in and help pressure build up? I tried to use
this as a drain (for recirculation) but find positive pressure causes the returning oil to be splattered about.
Ive just checked the fit of the Cortina trap into the block and its certainly not tight, interestingly there is no oil on the block beneath the
connection at all. i also checked where i pushed the rubber hose into the top grommet and it is just in (ie not to the base of the trap where oil
would gather).
[Edited on 2/10/07 by DarrenW]
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2b_pablo
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posted on 2/10/07 at 11:42 AM |
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for the sake of £7 Id maybe get one of the freeflowing block pipes to replace the cortina trap.
Burton sell them. EDIT part# FP280
Just to confirm the oil is coming out the filler cap tube?
[Edited on 2/10/07 by 2b_pablo]
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DarrenW
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posted on 2/10/07 at 11:58 AM |
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No, nothing from oil filler cap to report, only from crankcase.
ive just looked at the Burtons part again and from what i can see it is identical to the std sierra PCV but with no valve / plunger inside. I already
tried my modified PVC before and same happened. Does anyone know if the Burtons part is actually different or if my assumption is correct?
Ive looked to see if i can put the breather pipe directly into the block or not - yes o probs can but the angle is not good due to the manifold inlet
and water pipe connection directly above. I havent yet checked to see if the hole in block is straight through or if a tin baffle is fitted
underneath.
[Edited on 2/10/07 by DarrenW]
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2b_pablo
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posted on 2/10/07 at 12:01 PM |
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The burton one is just hollow so no obstrctions at all.
I had bought one but the cortina one I have is working ok so I didnt use it.
Sorry to take a step backwards but you have:
feed from the oil filler cap
feed from the block under the carbs
and another feed too?
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DarrenW
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posted on 2/10/07 at 12:10 PM |
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Yes, 3 breathers.
Std crankcase position via cortina trap.
Oil gallery plug (oposite side to trap) drilled out and tapped to take a fitting - piped to catch tank (bore on this probs 6mm or so but added to the
1/2" from trap).
Oil filler cap to catch tank.
Currently all 3 feeding into seperate 'tanks' so i can see which feeds the most oil. both crankcase breathers do by a mile. Virtually nowt
from oil filler cap (just vapour, not enough to collect liquid on short run).
All i can think now is the crankcase is pressuring too much or the sump design is allowing oil to be flung all over down below which finds its way out
of the hoses. Oil level is poss a tad too high but only halfway between mid and top mark on dipstick.
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2b_pablo
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posted on 2/10/07 at 12:19 PM |
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can you block up the new breather on the exhaust side to make it work like a conventional system and work from there?
I give my 2.1 pinto a lot of stick on the track and dont get much oil out at all (2-3mm in the tank from the last few months). I run about 4bar oil
pressure too (maybe 5bar when getting lots of stick).
I have an open tank with both pipes "hanging" into it but not to the bottom.
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RazMan
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posted on 2/10/07 at 12:28 PM |
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quote: Originally posted by DarrenW
All i can think now is the crankcase is pressuring too much or the sump design is allowing oil to be flung all over down below which finds its way out
of the hoses. Oil level is poss a tad too high but only halfway between mid and top mark on dipstick.
Thats sounds the most logical reason - have you modded the sump? If the oil is thrashed by the crank it will foam up and behave very strangely.
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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DarrenW
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posted on 2/10/07 at 02:27 PM |
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Here are some pics of the sump.
Pic 1 shows the front section plated in to increase forward capacity and the lump cut ready to be modded. You can also see some holes cut to allo oil
to fall into the extended piece.
Rescued attachment P5260350 resize.JPG
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DarrenW
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posted on 2/10/07 at 02:29 PM |
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The lump then modded to allow pick up hols and dipstick to enter. This was then inverted and welded into the sump as a baffle. You should also see
some Vee's i cut in original part of the sump.
Rescued attachment P5270352 resize.JPG
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DarrenW
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posted on 2/10/07 at 02:30 PM |
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Then the final modded sump the right way round after the 3mm thick plate was welded to the bottom.
So you can see that rather than cut the entire original base out of the sump ive left it in place and added holes and Vees as the baffle plates.
As far as my research went this is similar to some other modded sumps. I didnt go big wing route as my logic was extending forward added more
capacity. In real terms it takes between 5.5 to 6 litres of oil to between bottom and mid point on dipstick. If i fill over halfway i know it splashes
oil about excessively and it gets burnt off under hard acceleration. Once the level settle no oil is burnt off and the level remains dependant on
catch tank activity.
I can block off the oil gallry hole no problem and just use the 2 breathers pretty much as 2bpablo has shown with no problem so will try and do that
tonight.
I went home at lunch time, did 5 miles at 3K revs max and no oil was ejected. Heavy breathing seems dependant on level of thrash.
[Edited on 2/10/07 by DarrenW]
Rescued attachment P5270357 resize.JPG
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02GF74
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posted on 2/10/07 at 02:41 PM |
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quote: Originally posted by DarrenW
Yes, 3 breathers.
Std crankcase position via cortina trap.
Oil gallery plug (oposite side to trap) drilled out and tapped to take a fitting - piped to catch tank (bore on this probs 6mm or so but added to the
1/2" from trap).
Oil filler cap to catch tank.
What is this oil gallery plug connection to breather for? you're not tapping into a pressurised oil way????
I am not sure it has been said the crankcase breather works as follows.
It takes vapours from the crank to feed them to carbs where they are burnt off. Now at idle, the vacuuuuum in the carbs is high so they would suck
fumes from the crankcase upsetting the mixture hence there is a valve to stop that happening.
I suspect it starts to open when the crank pressure is high enough to push it open.
Remeber vacuum cannot ever be more than 14 psi but pressure in crank.
So do we know if this valve is functioning correclty? Is it the right part for the engine? If the bit is anything like that on the crossflow, it can
be taken apart and cleaned; it may be possible to fit a stronger spring. Is it closing as it should and any seals in good condition? (I know there
is an 0-ring on the xflow)
Easiest maybe to buy a new one or make something that works in same way.
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DarrenW
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posted on 2/10/07 at 03:23 PM |
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Is the oil gallery on a Pinto pressurised? If so this would certainly cause part of my issue so ill block it back off. I originally tapped out the oil
gallery plug to fit the oil temp sender so ill revert back to this for now.
Yep - std PCv valve does work more or less as you say. At low revs vacuum is at max and pulls the plunger open so gasses can be burnt off on std
engine via std carb. Now ive got multi carbs i cant do this. Original PCV was modded to remove springe valve (ie straight through) and later changed
for the cortina oil trap which again is straight through ish. As its not connected back to carbs any more i have this going to catch tank with the
resultant filling issues which could be due to opening the oil gallery (dont think so as catch tank filled before i did this), maybe sump design or
something causing excessive pressure in oil gallery.
When i close off the oil gallery again im back to the original issue of excessive oil being chucked up the crankcase breather pipe. At least i know
its not coming from oil filler cap though now.
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02GF74
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posted on 2/10/07 at 04:49 PM |
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I'm not familiar with pinto hence questions.
Oil gallery - what is that then? Is it some smallish hole in the casting that oil dribbles down from the top end into the sump? So if there is
pressure in the engine block, this oil would be under that same pressure surely? As opposed to oil pump pressure which would empy your engine oil!
crank case pressure is due to combustion gases getting past rings? so can't be due to any sump design or modification?
note these are questions rather than statments of fact.
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jacko
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posted on 2/10/07 at 04:50 PM |
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Darren do a photo of your engine the return plug i used was tapped when the block was made by fords to the rear of the exhaust
Is your dip stick the right one for the engine and is the dip stick tube the right length?
Graham
[Edited on 2/10/07 by jacko]
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02GF74
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posted on 2/10/07 at 04:55 PM |
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quote: Originally posted by DarrenW
Yep - std PCv valve does work more or less as you say. At low revs vacuum is at max and pulls the plunger open so gasses can be burnt off on std
engine via std carb.
not sure that is what I said. my understanding is the valve closes off at low rpm as you don;t want the carbs sucking up oil vapours at idle as it
upsets the mixture. I'll look it up again.
quote: Originally posted by DarrenW
When i close off the oil gallery again im back to the original issue of excessive oil being chucked up the crankcase breather pipe.
is this with modified valve? It should have the spring fitted.
the way I see it, and this could be wrong is that you have gasss pressure -due to combustion gases getting past rings and oil flung about as it comes
off the crank. I would guess that the ol is flung into the area of the valve and t he pressure is enough to force it out of the block.
Did you have problkem with the original PVC fitted as designed for the block?
(I understand why you have the need for a catch tank).
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02GF74
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posted on 2/10/07 at 05:00 PM |
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modified sump hmmmmmm - was there some baffle/windage plate whose purpose was to preven oil being flung up into the PCV thing or this oil gallery that
you removed?
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2b_pablo
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posted on 2/10/07 at 06:13 PM |
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as far as Im aware the crank breather is normally shut until the vaccum from the carbs pulls the valve open allowing the gases to escape (I guess
there is no real pressure at low revs).
When you fit twin 40s/45s or bike carbs you dont have this feed so the pressure is never realeased and finds another way out. In my case this was out
thru the filler cap or the dipstick or something.
Fitting a cortina trap and a vented cap fixed my problems entirely.
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02GF74
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posted on 3/10/07 at 08:45 AM |
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quote: Originally posted by 2b_pablo
as far as Im aware the crank breather is normally shut until the vaccum from the carbs pulls the valve open allowing the gases to escape (I guess
there is no real pressure at low revs).
^^^ that is what I said earlier but I was wrong - sorry!!
The valve is kept open by the spring. When engine is running at low rpm, the vacumm pulls the valve closed; as revs inscrease there is less suction
keeping it closed so it opens to allow combustion gases to be sucked by the carbs.
Since this valve is no longer connected to vacuum (carbs), it will be always open.
Here is somethig to try. Can you fit a coke can stuffed with those stainless steel pads with a tube at each end to the PCV vlave - abit like an in
line filter - throy being that any vaporised oil will condense in this big volume and drain back into the block.
Incidentally the haynes shows the pinto breathing system as sucking in air via the filler cap.
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2b_pablo
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posted on 3/10/07 at 08:49 AM |
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you sure mate? because before I fitted the cortina trap which doesnt need the vac connection I was getting pressure build up and oil out the filler
cap.
which would imply the breather was shut with no vac attached.
is there not MORE vac with rpm from the inlet manifold as the engine sucks in more air?
Just confused, not saying Im right.
[Edited on 3/10/07 by 2b_pablo]
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DarrenW
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posted on 3/10/07 at 10:05 AM |
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The std PCV valve is held shut by the spring. At low revs the vacuum is greater, pulls valve open and burns off gasses. As revs increase the air flow
increases and the vacuum is balanced out (this si how it was generally agreed a while ago and im sure the same as Burtons explain it).
Anyway i dont have a PCV anymore so i guess that discussion is academic. Also the first job that anyone who tunes Pintos does is junk the PCV or at
least remove the guts from it to make it straight through.
Im going to take a series of piccies in a mo to better show what i have now.
Keep up the discussions - it is helping.
No comments ref sump?? Ill add dims of dipstick and tube as well soon. Engine is from Granada so dont know if that makes a difference.
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2b_pablo
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posted on 3/10/07 at 10:07 AM |
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can you put a std sump on to test?
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02GF74
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posted on 3/10/07 at 10:44 AM |
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quote: Originally posted by 2b_pablo
you sure mate?
have words with Mr Haynes about his mk2 escort manual.
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