How to diagnose a cracked liner - MG-Rover.org Forums
 
LinkBack Thread Tools Rate Thread Display Modes
post #1 of 9 (permalink) Old 18-05-2017, 18:20 Thread Starter
nwc
Registered User
 
Join Date: May 2017
Car: Lotus Elise series 1 - Rover K engine.
Posts: 1
How to diagnose a cracked liner

Hi,

I got an Rover K engine in my Elise, it was running ok until I put it away for winter (2016) oil and coolant ok. Now in December I saw all the coolant was gone, and there was a LOT of "oil" in the engine. The engine was never started in this condition.

I assumed HGF.

When draining the "oil", the first lot was nice clear coolant -> so coolant did get into the oil (no coolant on the garage floor either).

When the head was removed, I checked the coolant in the area around the liners, there were the same amount around all 4liners, and it was "flush" with the engine top - the engine is tilted a bit forward when sitting in the car -> I assumed that the liners & liner sealing was ok

So I replaced the engine head, gaskets, oil etc. - a new head was actually cheaper than having the old head skimmed.

Everything put back together again with new gaskets. I also upgraded the oil rail in the sump to the improved stronger type, new head bolts and the SAIC type of head gasket.

The engine was not turned while the head was off, it was locked by the special tool that go into the starter gear ring.

I removed as much air as possible in the cooling system, by applying pressure to the cooling system via a special expansion tank cap I made, and loosing the bleed screw on the engine and on the radiator hose in the front.
While heating up the engine in order to get out the last air of the cooling system, I saw signs of water in the (new) oil (on the dip-stick).
Also, I saw that when the engine was rev'ed up to 2000rpm, the exhaust had lot of white smoke.
It had been running for apx. 10minuts. So I STOPPED!

Now, I suspect one or more of 3 faults:
- Inlet gasket - unlikely as it was replaced with a new Viton type (https://www.rimmerbros.co.uk/Item--i-LKJ101110)
-> I'll try to removed the inlet manifold, bolt on some small blanking plates over the water way holes in the head, put on (air) pressure to the cooling system, and see if coolant is still lost/get into oil -> If it is, the leak is inside the engine. Otherwise it might be the inlet/inlet gasket.

- Liners -> I'll try compression test to see if they are equal on all cylinders - Is there a better way? Can this tell me if the liners are cracked?

- Liner sealings -> How do it test if they are ok, without disassembling the lot again?

Now, if it is liner sealing failure, is it possible to re-seal the liners, without taking them completely out of the engine?
I was thinking about turning the engine until the piston (two of them) is in the bottom position, then keep turning until the piston+liner is in top position, then add sealing and turn the engine to seat the liner again. Then fix the liner to the head by some wood block, and do the other two same way.

Don't know if there is room for applying sealant/cleaning away the old sealing?
Could I reuse the SAIC head gasket? should I go for the MLS or elastomer type instead?

BR,
Peter
nwc is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 19-05-2017, 12:28
Registered User
 
Join Date: Nov 2011
Location: Stornoway, Isle of Lewis
Car: MG TF
Posts: 409
Can't wait to see the answers on this, as I might be in trouble with liner(s) too.
skellum is offline  
post #3 of 9 (permalink) Old 19-05-2017, 13:18
Registered User
 
Join Date: May 2014
Location: Bedford
Car: Evolution VII RS, MK5 RS2000, Trackday MK2 ZR 160, MK2 ZS 120+
Posts: 1,318
What gasket did you use? Were all the Liner heights ok?
JOHNDQ is offline  
 
post #4 of 9 (permalink) Old 19-05-2017, 15:44
Stuck in the 80's...
 
IanMc's Avatar
 
Join Date: Jun 2009
Location: Braintree, Essex
Car: Flame Red '95 MGF, 17 Mini Cooper S, 13 VX Astra, 15 VX Corsa & 59 Fiesta.
Posts: 4,639
Sadly there are no shortcuts here...

The liners cannot be resealed without dismantling the engine, they must be removed (slid out of the top of the block).

First rule though - assume nothing!, start with the basics/most simple, cheap and obvious things and work from there.

Why did you replace the head out of interest? Did you find any fault with the one fitted?

As John says above, you need to pay special attention to the heights of each liner before deciding upon which HG to use.

Note! never reuse any head gasket, even if the engine has never been started. The gasket has been compressed and therefore effectively scrap.

Good luck.

---------------------------------------------------------------------------------------------------------------------------------------------


For .org forum only search results in Google, add "site:mg-rover.org" after your search criteria

Treat others as you would like to be treated yourself.

Last edited by IanMc; 19-05-2017 at 15:50.
IanMc is offline  
post #5 of 9 (permalink) Old 19-05-2017, 15:59
Registered User
 
Join Date: Feb 2005
Location: Near Lincoln
Car: 06 MG ZR+120
Posts: 8,432
Quote:
Originally Posted by nwc View Post
So I replaced the engine head, gaskets, oil etc. - a new head was actually cheaper than having the old head skimmed.
A cylinder head skim typically costs around 40. If you bought a brand new head for less than that, I am sure a lot of people would love to know where

Quote:
I also upgraded ....to the SAIC type of head gasket.
The MLS types of gasket are often regarded to being less tolerant of out of spec liner stand proud than the elastomer type. You need to have measured the stand proud of each liner, and ensured that at the least, they are of even stand proud across all liners. Ideally, they need to be over 3 thou, but you would probably be alright down to one thou if they are all the same.

Quote:
- Liners -> I'll try compression test to see if they are equal on all cylinders - Is there a better way? Can this tell me if the liners are cracked?
Compression test will tell you if there is a leak from the cylinder - it won't allow you to distinguish whether it is due to worn valves, worn piston rings, HGF or a damaged liner though.

Quote:
Now, if it is liner sealing failure, is it possible to re-seal the liners, without taking them completely out of the engine?
I would think the sealant is unlikely - it is only there to stop weeping of coolant into the sump. The liners are a fairly snug fit on the shoulder in the block, and wouldn't normally allow coolant to leak past them at any great rate (according to someone who did a lot of test work on the K series during its development). You won't be able to apply new sealant to them without removing them from the block. However, it is usually possibly to remove the liner without needing to completely dismantle the bottom end.

Quote:
Could I reuse the SAIC head gasket? should I go for the MLS or elastomer type instead?
You won't be able to re-use any of the head gasket types - they all work on a principle of the clamping force between head and block/liners crushing some part of them to form a tight effective seal. You would need another new gasket if you take the head off again. As to which is best to use, you can only judge from measuring the liner heights/stand proud. If the stand proud is below 1 thou or uneven, it is often suggested that the original type SLS/elastomer gasket may be more effective. If the liners are flush with the block face, it is debateable whether any of the gaskets would seal effectively for very long, and if the liners have sunk below the head face (usually the result of the liner seats being damaged/softened due to gross overheating), then the only options are a replacement block, or shim the liners back up to their specified height (Brown and Gammons used to sell sets of 3 thou shims for this purpose, but I am unsure whether they are still available).

All things being equal, liner heights even and 2 thou plus, I would have no hesitation in using the SAIC gasket - I've had one in my ZR 120 for four years and over 25k miles now with absolutely zero coolant loss.

There isn't any way to check the liners for damage without taking them out, but it needs to be said at this point, that cracked liners (although not unheard of) is a rarity on these engines. I would discount the IMG; even if that is leaking, you will be unlikely to get coolant into the sump from that source, and certainly not the quantity you have found after a short engine run (unless the piston rings are very badly worn - in which case you would have bigger problems than coolant loss!).
Man in the Car is offline  
post #6 of 9 (permalink) Old 19-05-2017, 18:33
Registered User
 
Join Date: Sep 2015
Car: MG ZT
Posts: 15
did you straight edge your cyclinder head ? was it brand new ? either way i have had new heads that are ever so slightly out of true from new !! and a second hand one will definately have been warped .

assuming it is true and straight , i have had 3 k series engines with dropped liners in the past so i think that is a definate possibility

i have never heard of a cracked liner on a standard engine only on heavily tuned k series engines , you could pressurise the cooling system and then remove the plugs and put the pistons to the bottom of each cyclinder and look inside for signs of water , but this would not show a leak on the bottom of the liner itself
arrsyarry is offline  
post #7 of 9 (permalink) Old 19-05-2017, 20:37
Stuck in the 80's...
 
IanMc's Avatar
 
Join Date: Jun 2009
Location: Braintree, Essex
Car: Flame Red '95 MGF, 17 Mini Cooper S, 13 VX Astra, 15 VX Corsa & 59 Fiesta.
Posts: 4,639
I have had a cracker liner...

---------------------------------------------------------------------------------------------------------------------------------------------


For .org forum only search results in Google, add "site:mg-rover.org" after your search criteria

Treat others as you would like to be treated yourself.
IanMc is offline  
post #8 of 9 (permalink) Old 19-05-2017, 21:39
Registered User
 
Join Date: Sep 2015
Car: MG ZT
Posts: 15
thats unlucky what caused yours? were you running coolant with a low antifreeze content ? ive had that in other engines
arrsyarry is offline  
post #9 of 9 (permalink) Old 19-05-2017, 22:09
Stuck in the 80's...
 
IanMc's Avatar
 
Join Date: Jun 2009
Location: Braintree, Essex
Car: Flame Red '95 MGF, 17 Mini Cooper S, 13 VX Astra, 15 VX Corsa & 59 Fiesta.
Posts: 4,639
Quote:
Originally Posted by arrsyarry View Post
thats unlucky what caused yours? were you running coolant with a low antifreeze content ? ive had that in other engines
No, it was caused by hydraulic lock brought on by a weeping IMG. It also bent the con rod in the process - I keep this on a shelf in my garage as a reminder

---------------------------------------------------------------------------------------------------------------------------------------------


For .org forum only search results in Google, add "site:mg-rover.org" after your search criteria

Treat others as you would like to be treated yourself.
IanMc is offline  
post #10 of 9 (permalink) Old 20-05-2017, 09:21
Registered User
 
Join Date: Sep 2015
Car: MG ZT
Posts: 15
got me thinking last night , every k series i have ever had in with lower end trouble has always been in an mgf , mgtf , or lotus elise , had a couple last yr one with rattling little ends with only 28,000 miles and another with a sheered crank for no apparent reason,

im guessing they must get more of a beating on the rd or the tight engine bay has something to do with it
arrsyarry is offline  
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the MG-Rover.org Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes Rate This Thread
Linear Mode Linear Mode
Rate This Thread:



Similar Threads
Thread Thread Starter Forum Replies Last Post
KV6 - Head gasket or cracked Liner or ?? h4house MG ZT / Rover 75 (Sponsored by Rimmer Bros) 11 18-01-2013 16:04
Cracked liner or HGF? gnu MG ZR / Rover 25, 200 & Streetwise 6 13-12-2010 17:32
cracked liner wjsds1 MGF and MGTF (Sponsored by MGFnTFBITZ) 2 07-11-2010 08:40
vvc cracked liner - advice please folks devon vi MG ZR / Rover 25, 200 & Streetwise 36 01-04-2008 14:01
Cracked Liner NUTS RuS Others 6 28-03-2004 15:24

Posting Rules  
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome