Kv6 can cover breather

genpk · 30th November 2017, 02:47

Ok learned ones !!
As mentioned had an issue with the 12mm breather pipe plug breaking on the rear left side of the rear cam cover.
Can’t get a replacement 12mm plug as they only make the 9 mm fitting which is on the right side end of the cam cover.
Took the cam cover off, cleaned all the crud out but found a bit of a puzzle.
The smaller 9mm plug which has a one way valve inline in the piping appears to have no breather hole in the fitting or in the cam housing unlike the larger 12mm one at the other end which has a large hole in the housing.
My question is, can anyone tell me if the smaller pipe is actually drawing anything from the rear cam cover ? and if not why does it have a pipe connected.
Secondly ,as the internals on the larger 12mm fitting have disintergrated ,is supposed to be any sort of restriction (small hole) that’s supposed to be in the fitting or is it just a straight through hole into the cam cover ?

vitesse · 30th November 2017, 08:12

Didn't think my cam cover had the smaller breather either until some TIG wire (1.2mm) persuaded the hole to reveal itself

Regards

genpk · 30th November 2017, 10:40

Your right, finally found the tiny hole on the 9mm fitting all blocked up with rock hard crud.Cleaned it all out.
Ive re assembled the cam cover assuming the 12mm hole fitting is just straight through into the cam cover with no restriction.
I’m wondering if it is supposed to be the same as the same size fitting on the front cam cover which has a small hole inside the fitting.?
Tried looking into the fitting on one of my other kv6 cars and they seems straight through.
Worst comes to worst I can put some sort of restriction inline in the pipe if needed .

vitesse · 30th November 2017, 12:49

Going on memory which isn’t the best but also believe it’s a straight through hole with no restrictions. If wrong I guess someone will be along sharpish to tell us otherwise.

Regards

trikey · 30th November 2017, 16:51

It’s like that on all of them! I thought it was strange too

Typhoon190 · 30th November 2017, 18:06

As you've found, it should have a small diameter breather hole which is often blocked, causing condensation to build quickly on short runs, and make it look like HGF.

genpk · 30th November 2017, 22:10

I assumed as the front 12mm fitting had a small hole in it the rear bank would be the same.
Next question, as I now have removed the small hole restrictor inside the fitting and now have it running straight through with a larger hole, will that affect the running of the motor?
I’m assuming the small hole was there to restrict some of the oil going into the pipe.?

vitesse · 1st December 2017, 08:28

The most comprehensive description of the breather system I’ve seen is the Haynes one, where under conditions of idle the gases are sucked out of the crankcase by the smaller pipe and fresh air introduced via the larger into the crankcase. But when accelerating or full throttle both pipes are used to exhaust the gases.

If you haven’t got a copy I could PM it to you.

genpk · 1st December 2017, 11:06

Ive got a Haynes manual but thanks for the offer.
If anyone has a spare rear cam cover they may
lbe able to see if the larger hole fitting has any sort of restriction in it or is it just a straight through into the cam cover.

Dansrockin · 1st December 2017, 13:04

I don't want to sound a bit dim, but can anyone write a description of what's involved in taking the cam covers off to clean the breather holes, is it just a case of undoing the bolts that go round and taking out the spark plugs? Do the gaskets need replacing? I really think I need to do this on my 190, I get a lot of condensation coming from the breather pipe going into the front of the throttle body when idling. I've changed the oil, and also changed the inlet manifold gaskets, and I'm not losing coolant, so I don't think it's anything more than condensation in the engine.

30th November 2017, 02:47	#1
genpk Posted a thing or two Rover 75 Saloon MGZT Join Date: Jul 2012 Location: Perth, AUSTRALIA Posts: 1,667 Thanks: 3 Thanked 461 Times in 299 Posts	Kv6 can cover breather Ok learned ones !! As mentioned had an issue with the 12mm breather pipe plug breaking on the rear left side of the rear cam cover. Can’t get a replacement 12mm plug as they only make the 9 mm fitting which is on the right side end of the cam cover. Took the cam cover off, cleaned all the crud out but found a bit of a puzzle. The smaller 9mm plug which has a one way valve inline in the piping appears to have no breather hole in the fitting or in the cam housing unlike the larger 12mm one at the other end which has a large hole in the housing. My question is, can anyone tell me if the smaller pipe is actually drawing anything from the rear cam cover ? and if not why does it have a pipe connected. Secondly ,as the internals on the larger 12mm fitting have disintergrated ,is supposed to be any sort of restriction (small hole) that’s supposed to be in the fitting or is it just a straight through hole into the cam cover ?

30th November 2017, 16:51	#5
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,812 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	It’s like that on all of them! I thought it was strange too __________________ Lest we forget..

30th November 2017, 08:12	#2
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,556 Thanks: 395 Thanked 823 Times in 652 Posts	Didn't think my cam cover had the smaller breather either until some TIG wire (1.2mm) persuaded the hole to reveal itself Regards

30th November 2017, 10:40	#3
genpk Posted a thing or two Rover 75 Saloon MGZT Join Date: Jul 2012 Location: Perth, AUSTRALIA Posts: 1,667 Thanks: 3 Thanked 461 Times in 299 Posts	Your right, finally found the tiny hole on the 9mm fitting all blocked up with rock hard crud.Cleaned it all out. Ive re assembled the cam cover assuming the 12mm hole fitting is just straight through into the cam cover with no restriction. I’m wondering if it is supposed to be the same as the same size fitting on the front cam cover which has a small hole inside the fitting.? Tried looking into the fitting on one of my other kv6 cars and they seems straight through. Worst comes to worst I can put some sort of restriction inline in the pipe if needed .

30th November 2017, 12:49	#4
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,556 Thanks: 395 Thanked 823 Times in 652 Posts	Going on memory which isn’t the best but also believe it’s a straight through hole with no restrictions. If wrong I guess someone will be along sharpish to tell us otherwise. Regards

30th November 2017, 18:06	#6
Typhoon190 This is my second home MG ZT-T 190 Monogram Typhoon Join Date: Jan 2009 Location: Oxfordshire Posts: 4,716 Thanks: 328 Thanked 557 Times in 443 Posts	As you've found, it should have a small diameter breather hole which is often blocked, causing condensation to build quickly on short runs, and make it look like HGF.

30th November 2017, 22:10	#7
genpk Posted a thing or two Rover 75 Saloon MGZT Join Date: Jul 2012 Location: Perth, AUSTRALIA Posts: 1,667 Thanks: 3 Thanked 461 Times in 299 Posts	I assumed as the front 12mm fitting had a small hole in it the rear bank would be the same. Next question, as I now have removed the small hole restrictor inside the fitting and now have it running straight through with a larger hole, will that affect the running of the motor? I’m assuming the small hole was there to restrict some of the oil going into the pipe.?

1st December 2017, 08:28	#8
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,556 Thanks: 395 Thanked 823 Times in 652 Posts	The most comprehensive description of the breather system I’ve seen is the Haynes one, where under conditions of idle the gases are sucked out of the crankcase by the smaller pipe and fresh air introduced via the larger into the crankcase. But when accelerating or full throttle both pipes are used to exhaust the gases. If you haven’t got a copy I could PM it to you.

1st December 2017, 11:06	#9
genpk Posted a thing or two Rover 75 Saloon MGZT Join Date: Jul 2012 Location: Perth, AUSTRALIA Posts: 1,667 Thanks: 3 Thanked 461 Times in 299 Posts	Ive got a Haynes manual but thanks for the offer. If anyone has a spare rear cam cover they may lbe able to see if the larger hole fitting has any sort of restriction in it or is it just a straight through into the cam cover.

1st December 2017, 13:04	#10
Dansrockin Posted a thing or two MG ZT number 1 of 25 celestial!! Join Date: Feb 2012 Location: Banbury Posts: 1,967 Thanks: 208 Thanked 242 Times in 166 Posts	I don't want to sound a bit dim, but can anyone write a description of what's involved in taking the cam covers off to clean the breather holes, is it just a case of undoing the bolts that go round and taking out the spark plugs? Do the gaskets need replacing? I really think I need to do this on my 190, I get a lot of condensation coming from the breather pipe going into the front of the throttle body when idling. I've changed the oil, and also changed the inlet manifold gaskets, and I'm not losing coolant, so I don't think it's anything more than condensation in the engine.