hi guys. A small but rather annoying problem with my crossflow. Its 1640cc on twin carbs, pretty standard apart from that.

Reving it at a standstill does nothing, but after a bit of hard driving, there is oil running everywhere under the bonnet. Its coming from the breather, i know cos i stuffed a rag in and it was absolutely soaking after about 10 mins. Nearly got me chucked off track (literally, i was on the tannoy! )

So, what could cause this? i lost a hell of a lot of oil in just a few hours (from 3/4 on the dipstick to nearly nothing). Main problem is the mess.

Im thinking a catch tank would solve this, but surely theres no reason for all this oil coming out? Something blocked? too much oil? Wrong dipstick?

There is also a small amount of smoke from the breather, would this indicate worn rings?

Any help appreciated

Did the original carb connect to the breather and suck the oily fumes back into the inlet?

The pinto's have a 1way valve in the breather that only opens when it is sucked open by the carb,
we didn't realise this and oil was even coming out of the filler cap.

Does it have a vented filler cap Joel ?

Sure this has been covered recently. Worth a search?

Hi Joel,

Have a read of this

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

I know Dave is talking about a Pinto but I think that the principle is similar

Cheers

Mark

it does sound likely that it should be connected to the carbs, but it would still run out of oil every 2 days! cant work it out myself. Rusty, i dont recall it being discussed recently, do you remember any threads? there are no obvious keywords to search for

Naah when its working properly its only the oil vapour that gets sucked into the carb.

When the crankcase etc get pressurised because of insufficient breathing thats when it spits out liquid oil

quote:

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Originally posted by Peteff
Does it have a vented filler cap Joel ?

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Go back about 8" from the dizzy - there is normally a little rectangular box with a pipe going to the inlet manifold. This is the normal type of x-flow crankcase vent.

If the hole in the block has been plugged up then that's the source of your troubles. Either get a replacement valve box from the scrappy, or buy a racing-style vent that has a pipe to a catch tank.

Someone else had the same problem a while ago - he found that the vent hole had been plugged with a bit of wooden dowel!

rgds,
David

had the same problem with my 1700 xflow.assumed it was down to leakage past the rings and crank case being pressurised . fitted largest diameter pipe from side of block using a burton power adapter ,then into side of rocker cover .this re-cycled the oil back into the engine , fumes were the tapped off from the other end of the rocker cover into a catch tank.
also check you have not over filled with oil ,this could end up being forced out by crank rotation.

forgot to mention ,i also unvented the rocker cover cap , cos it was pissing out of there as well ,fitted a self tapper in the one milli hole .
the engine is well worn i think ,but still goes well .

Mine's same but not as bad
Its fitted with some kind of filter (on top of the breather pipe) vented to atmosphere, which is ok but good hard drive & you have instant rust proof to the enigne bay. Was thinking of re routing the pipe near to the air filter or would this give me probs with the carb then ?

not good if the carbs take in too much oil ,with over enrich the mixture and soot up the plugs. mine has twin 40 webers which were never intended to take in and re-cycle engine fumes .

Sounds a bit more than breather problems to me, definately has the sound of broken, or seized piston rings, or really badly worn bores. Have you done a compresion test on it. If it was mine that would my first check. IMHO.

Joel..U2U sent.....
Fozzie

I had this problem and tried all the advise given, (different ways of plumbing the breather/catch tank etc)

In the end I got so fed up I swapped the block. All ok after that

But as you said, it's not so bad it just the mess!!!

Mark

[Edited on 19/11/05 by Markp]

cheers all, will sort through posts tonight (im off to work now ), and maybe add a few pictures.

To summarize briefly, i have a small 1mm hole in the oil cap, the block breater behind the carbs just had a wire filter stuck in it, and this is where it all comes from.

cheers!

Just started the new engine on the caterost, old one had excatly this issue and it had a seized ring, pressurised the crank and push oil out into the catch tank as quick as it could go in!! Newly rebuilt engine now is fine, think its time for a rebore mate.

Mac

1660ccs calling... its either that or approx 899cc

quote:

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Originally posted by darrensdad
not good if the carbs take in too much oil ,with over enrich the mixture and soot up the plugs. mine has twin 40 webers which were never intended to take in and re-cycle engine fumes .

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Totally agree. Worn/siezed/knackered rings allowing pressure into the sump. My old 1300 sufferes from this but a) it's not really bad enough to do anything about it (yet), b) I don't see any point in spending out to rebuild the 1300 and c) I know I need to replace the engine but cant decide to go for the easy option (1600 xflow) or something else (?)
Incidentally, blocking it up to stop it being ejected will just lead to other problems because it will get out somehow.

Jools,pick up a second hand MR2 lump and adaptor for the ford box,same size/weight engine but will leave a tuned crossflow for dead for a few hundred quid.
C'mon Jools you know you feel the need for SPEED!