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Nick
31-05-08, 06:08 PM
On my 1600 T40, i've allways had an oil leak when the car gets some serious thrashing.

When it's just pootling around it seems to hold it's oil perfectly. I can't see quite where it's coming from, but i suspect its from the crankcase pick-up, as the oily gunk is all over the top of the starter motor e.t.c. So i don't think it's Crank Seal e.t.c or anything major.

Problem is, i'd not checked it in a couple of days and i've been blasting up and down motorways all last week.The Oil light hasn't come on in the car, but the Oil level is right on the bottom of the dipstick.

I know the importance of oil, but roughly how much will be left in the sump !? I'm going to be gutted if i've caused some sort of fatal damage :(

Also, i use Valvoline VR 1 Mineral Racing (i think it's a mineral oil), i can't get hold of any around here, so i presume it's ok to throw in some similar 20-50 Mineral oil ?

Adam
31-05-08, 06:15 PM
Definently not the back of the rocker cover gasket?
Or between the cam housing and head?

Nick
31-05-08, 06:17 PM
Nope, Rocker cover gasket is brand new. And there doesn't seem to be any problems between the head and Cam housing.

It's hard to see really, and i can't get under the car as it's too low at the front :( .

I THINK there is an ugly looking 90 degree custom made metal pipe that comes directly off the crankcase and onto the breather pipes. Which seems to be the culprit.

mikey14sr
31-05-08, 06:19 PM
Sounds like there could be a hole or a leaking gasket on the oil seperator unit, do you have it venting to air or plumbed back into the cam housing?

Nick
31-05-08, 06:21 PM
Do you mean the oil seperator unit in the Rocker Cover !?

I basically have the crankcase breather pipe-work, t peiced into the cam housing, and then into a tank.

http://img.photobucket.com/albums/v626/j829nick/IMG_2664-1.jpg

Ignore the Red and arrows. that was for something else..

The leak is definetly coming from the bottom backside of the engine. Everything else is nice and clean, apart from the sump, and half the floorplan ha

mikey14sr
31-05-08, 07:40 PM
Ahh, forgot that on multipoints it's just a tube coming up the back out of the crankcase, on all others there's a seperator tank down there. Could be that where it bolts to the block the gasket's goosed or it might have come loose?

Only other thing I can think of throwing oil out down there if the head and cam box are dry is a hole in the block.

Nick
31-05-08, 08:31 PM
The whole engine was rebuilt less than 6k ago.. I'm stumped. Untill i have a look i guess i wont beable to tell what it is.

I'm more worried about how low the oil has gotten without me realising !

Thanks for the Replies

mikey14sr
31-05-08, 08:36 PM
I've known people top the oil up and then realise the catch tank is full, drained yours lately?lol

Nick
31-05-08, 08:37 PM
I drained it recently. but i'm going to check it again tommorow.

Although, there is a large amount of oil around the back of the engine, bottom of the box e.t.c and all down the floor plan !

AlexW
31-05-08, 11:02 PM
By the way, If your oil light comes on, Its too late.

ck
01-06-08, 03:43 AM
lol thats generaly the way. my old c16xe'd corsa the valve stem seals were shot and smoked sh1t loads. would get to the point just as the oil is not showing on the dipstick (yes it burnt alot) it would then start tapping quite bad and start becoming slugish lol. oil light used to come on when it was very low when going round certain corners. engine never complained, loved the limiter and never died :D.

MC
01-06-08, 06:55 AM
It's normal for the 8v engines to spit oil out the crank case vent when you thrash them. Do you have a pipe direct from the block to your tank or is it going through a black seperator box? If it is a box have you got both pipes taken care of? CP made a device that allowed the pressure to vent and the oil to drain back into the block which was very effective. Consisted of a pipe from the block running up into a larger bore pipe of about 50-60mm internal diameter and about 200-300mm long with a normal pipe of the top to a breather. Keep the large bore pipe vertical and the pressure pushes through and the oild drains back down.

I used to have to clean my engine bay after every thrash!

Stuart
01-06-08, 08:06 AM
I used to have to clean my engine bay after every thrash!

so every day then :thumb:

MC
01-06-08, 08:17 AM
Me!?

Adam
01-06-08, 10:57 AM
It's normal for the 8v engines to spit oil out the crank case vent when you thrash them.
Aye, something to do with the crank design forcing a lot of oil up the breathers at high revs iirc.

GroupA cars have the breather outlet on the block just blanked off with a plate to stop the problem.

Nick
01-06-08, 11:38 AM
It's normal for the 8v engines to spit oil out the crank case vent when you thrash them. Do you have a pipe direct from the block to your tank or is it going through a black seperator box? If it is a box have you got both pipes taken care of? CP made a device that allowed the pressure to vent and the oil to drain back into the block which was very effective. Consisted of a pipe from the block running up into a larger bore pipe of about 50-60mm internal diameter and about 200-300mm long with a normal pipe of the top to a breather. Keep the large bore pipe vertical and the pressure pushes through and the oild drains back down.

I used to have to clean my engine bay after every thrash!

As far as i can see, i've got one Pipe coming from the Crankcase and up into the tank (which also T's into the Cam housing vent)

Have i been a total retard and missed another pickup on the block ?

Adam
01-06-08, 11:42 AM
So you have no seperator box on the back of your block?
Just a pipe straight from the block?

Adam
01-06-08, 11:45 AM
You can see the seperator box on the back of my old 1400 in this pic:
The breather pipes then come from that box.

http://img.photobucket.com/albums/v86/Nova-crew/P1010009asdsad.jpg

mikey14sr
01-06-08, 12:01 PM
the multipoint injection engines dont have that seperator, they have it built in to the cam cover, with just a metal pipe coming up from the crankcase that feeds into the camshaft housing, ahh that could be it?

GroupA spec had a blanking plate on the crankcase and a pipe from the rocker cover into a catch-tank.

Adam
01-06-08, 12:05 PM
I bet thats the problem then.
Nicks running the pipe straight from the block into the catch tank, instead of through the rocker cover seperator because i dont think his cam housing has the breather pipe connection on it (old 1200 carb cam housing?)

Nick
01-06-08, 12:13 PM
I bet thats the problem then.
Nicks running the pipe straight from the block into the catch tank, instead of through the rocker cover seperator because i dont think his cam housing has the breather pipe connection on it (old 1200 carb cam housing?) http://img.photobucket.com/albums/v626/j829nick/IMG_2664-1.jpg

That's the setup. However, There is no Oil seperator inside the rocker cover ! And yes, it's the Old 1200 Cam housing. Are the 1600 and 1200 cam housings different ?

I don't have seperator at the crankcase either. Just a straight exit pipe.

Adam
01-06-08, 12:19 PM
Yeah there different.
As mikey said, the mpi cam housings have a breather connection(for that hose from the block), and the rocker cover then vents to the inlet/catch tank.
Youve got the block pipe going straight to the catch tank, which is why your getting a load of oil and crap chucked up into the tank.
It should be going into the cam housing........

Adam
01-06-08, 12:23 PM
Another pic :D
You can see the cam housing breather conneciton
http://img.photobucket.com/albums/v86/Nova-crew/Nova%20WIP%20pics/60-Newhead.jpg

Which makes any oil coming up the block pipe drip straight back into the head......
And then gases etc vent out of the rocker cover(via those small hoses on it)

Because youve got no cam housing connection, all the breather pipes contents are going striaght into your catch tank ;)

mikey14sr
01-06-08, 01:12 PM
^^ thats the beasty, only like that on multipoint 1.4+1.6 engines.

Nick
01-06-08, 04:36 PM
Ahhhhhhhh crap !

Still doesn't explain why it's appearing all down the back of the block though... I don't think the catch tank has much oil in it.

Adam
01-06-08, 05:47 PM
Aye, it doesn't explain that.
But that pipe might be getting full with oil and leaking or something?
Get it up on stands and have a peek up behind the block.

MC
01-06-08, 06:54 PM
Any chance catch tank is full and building pressure in the pipe? Leaking at the base?

Nick
01-06-08, 08:11 PM
The Base connection was made by the chap who rebuilt my engine. It's fooking hard to see down behind there, but it appears to be a nasty looking bit of 90 degree thin metal pipe.

I'm guessing it's just causing too much pressure in the crankcase ?I'm going to make some fatter pipework and try and improve that connection. Also, i'm guessing too much crankcase pressure isn't going to be doing much good for the power output fom the engine ?

The tank shouldn't be full. i still havn't looked, but i don't think that's the problem - Judging by the amount of oil on the back/bottom of the engine and car !

Ash
01-06-08, 08:22 PM
I maybe able to help here....

I'll get a pic in a min, but I'm running a hose from the metal pipe (that I cut down) up round the inlet and into the cam box. Then I'm running one from the rocker cover to an oil catch tank with a breather.

EDIT:
http://img119.imageshack.us/img119/5792/08032008542pt2.jpg (http://imageshack.us/)

You can see the 90deg hose just poking out behide the carb and the 45deg attached to the cam box, and then the U-bend on top to join the two. I'll try and find a better pic....

What your problem could also be is a leaking crank shaft seal. Mine is leaking atm on to the flywheel and then collecting both at the bottom and somehow making it's way along the starter motor....

Nick
01-06-08, 08:25 PM
I wouldn't say it's a leaking crank shaft seal personally. The oil seems to come from the back of the block down, and then it looks like it's dripping from the crank-seal area.

Oil leaks a complete pain in the **** unless everything is super clean !