Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Search Today's Posts Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 22nd August 2019, 12:58   #1
PC2
Regular poster
 
MG ZT-T 190

Join Date: Mar 2016
Location: Brighton
Posts: 53
Thanks: 1
Thanked 3 Times in 3 Posts
Default ZT-T 190 disappearing oil?

I know I've been on about this before, and thought I'd discovered the problems and solution with weeping cam end seals and covers (now replaced) but....

Ok, my 190 has just done 61K. No rattles, no knocking, VIS working, pulls really well, very smooth, regularly serviced, no sign of oil leaks around engine or undertray, no smokey exhaust, no burning oil smells, no evidence of excessive oil in the breather pipes or air filter pipe, I follow the correct dipstick procedure, yet it is using about 1 litre of oil per 1800 miles.

Logic says the oil is going somewhere. It's going to send me completely mad. Yes I can keep topping up, but surely this is a sign of something not right and potentially serious. I fear this is going to break me.

Any more thoughts and ideas gratefully received!
PC2 is offline   Reply With Quote
Old 22nd August 2019, 13:27   #2
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Rover 3500 Vanden Plas (1984).

Join Date: Mar 2007
Location: Middlesex
Posts: 15,941
Thanks: 839
Thanked 2,502 Times in 2,163 Posts
Default

So Paul, the level on the dipstick reads 'max' and after 1,800 miles it reads 'min', have I got that right?

The scale on my dipstick is black plastic which makes seeing the level virtually impossible. I therefore press it against a sheet of kitchen towel to see the reading. If your dipstick is the same, you might like to try that.
Here is the MG Rover procedure again.

But there can only be three ways your engine can use oil:
  • It's leaking and you haven't found the source yet. Have you removed the undertray and inspected underneath with a powerful torch?
  • The engine is burning it.
  • You're misreading the dipstick.

Oil can't just disappear! Car maintenance can be very frustrating and mysterious at times.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Old 22nd August 2019, 15:34   #3
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 10,004
Thanks: 2,291
Thanked 1,041 Times in 910 Posts
Default

If you can find no external leaks then it's probably getting past the piston rings and getting burnt.

One litre in 1800 miles won't show as a smoky exhaust.--
__________________
COLVERT is offline   Reply With Quote
Old 22nd August 2019, 18:05   #4
PC2
Regular poster
 
MG ZT-T 190

Join Date: Mar 2016
Location: Brighton
Posts: 53
Thanks: 1
Thanked 3 Times in 3 Posts
Default

Thanks Simon
Yes oil check as per instruction.
Dipstic is actually green on this car.
I've checked the oil so many times now, the results the same.

Colvert - if the oil was getting past the rings and burning, I think there would be tell tale signs on the exhaust pipe and also you are likely not to have the performance and probably some rattle/vibration.
The engine is tight and fast and feels like a 60k engine should.
I know i might be wrong, but this is the third ZT-T ive had (190, 180, 190) and the fastest and smoothest.
If the rings are a problem, is there an easy test other than a compression test?

Thanks
PC2 is offline   Reply With Quote
Old 22nd August 2019, 18:17   #5
Phil-T4
I really should get out more.......
 
Phil-T4's Avatar
 
MG ZT-T, Rover 75 Tourer

Join Date: Mar 2011
Location: Olney
Posts: 2,842
Thanks: 231
Thanked 938 Times in 589 Posts
Default

Quote:
Originally Posted by PC2 View Post
If the rings are a problem, is there an easy test other than a compression test?
Yes, its called a leak down test
Phil-T4 is offline   Reply With Quote
Old 22nd August 2019, 18:55   #6
PC2
Regular poster
 
MG ZT-T 190

Join Date: Mar 2016
Location: Brighton
Posts: 53
Thanks: 1
Thanked 3 Times in 3 Posts
Default

Thanks Phil - i don't think that's any easier, or cheaper!
PC2 is offline   Reply With Quote
Old 23rd August 2019, 20:01   #7
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 10,004
Thanks: 2,291
Thanked 1,041 Times in 910 Posts
Default

The thing is, that it's quite a lot of oil to vanish without leaving quite a large trace somewhere which is why I suggested that it might be getting burnt.

It could be something else but if it was slight wear on the rings that would not make any noise at all.

Good luck with your search.---
__________________
COLVERT is offline   Reply With Quote
Old 23rd August 2019, 21:09   #8
PC2
Regular poster
 
MG ZT-T 190

Join Date: Mar 2016
Location: Brighton
Posts: 53
Thanks: 1
Thanked 3 Times in 3 Posts
Default

Colvert - yes I really can't think of any other solution to this other than a very high pressure leak somewhere that may be being burnt off on the manifold or similar, but there is no evidence. So perhaps it is the rings, and maybe its always been like it.
I suppose I just don't like the thought of burning oil, and the engine certainly doesn't seem to lack compression, and its only just hit 62K. I also hate leaving a mystery unsolved, but maybe I should just carry on topping up with oil every 1000 miles or so and stop worrying about it.
I wonder whether the emissions test could pick up burning a bit of oil?
PC2 is offline   Reply With Quote
Old 23rd August 2019, 22:20   #9
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 20,380
Thanks: 239
Thanked 2,970 Times in 2,432 Posts
Default

Quote:
Originally Posted by PC2 View Post
I wonder whether the emissions test could pick up burning a bit of oil?

I'd have thought so. They test for hydrocarbons in the exhaust. This is basically unburned fuel, but with oil going in as well, I'd expect that reading to go asymptotic.


TC
T-Cut is offline   Reply With Quote
Old 24th August 2019, 14:07   #10
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 10,004
Thanks: 2,291
Thanked 1,041 Times in 910 Posts
Default

Quote:
Originally Posted by T-Cut View Post
I'd have thought so. They test for hydrocarbons in the exhaust. This is basically unburned fuel, but with oil going in as well, I'd expect that reading to go asymptotic.


TC
Or perhaps leaving it, as an exponential oil leak must show itself eventually.


----
__________________

Last edited by COLVERT; 25th August 2019 at 14:37..
COLVERT is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 10:17.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright © 2006-2019, The Rover 75 & MG ZT Owners Club Ltd