Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[JamesV6CDX]

Just went out with a friend and did a compression test on all 4 pots on the lemon 2.0, it's always so much better with 2 heads.

The tester is OK and we made a tight seal.

Pot number 1: No reading at all, guage just flickers and then goes back to zero.
Pot number 2: No reading at all, guage just flickers and then goes back to zero.
Pot number 3: About 4 bar of pressure
Pot number 4: About 8 bar of pressure.

All spark plugs are black, wet and manky.

Can anyone confirm what this is telling me?!

[Auto Addict]

Valves?

[JamesV6CDX]

Valves?

I really don't know, turning on the starter there sounds like there is good compression and it's having to work to turn the engine..

But there's obviously something seriously wrong.

What would explain all the plugs being wet and black?

[TheBoy]

Just went out with a friend and did a compression test on all 4 pots on the lemon 2.0, it's always so much better with 2 heads.

The tester is OK and we made a tight seal.

Pot number 1: No reading at all, guage just flickers and then goes back to zero.
Pot number 2: No reading at all, guage just flickers and then goes back to zero.
Pot number 3: About 4 bar of pressure
Pot number 4: About 8 bar of pressure.

All spark plugs are black, wet and manky.

Can anyone confirm what this is telling me?!

Its Donald Ducked.  I suspect the cambelt isn't (or hasn't been) on right

[Matchless]

I would guess valve timing has slipped or been set wrong at some point resulting in bent valves, you will only find out for sure by removing the head.
The lack of pressure on 1 & 2 could be a seriously blown gasket but that wouldnt explain why 3 & 4 are low as well.

The cam belt cover should have a rib moulded in it which lines up with a notch in the crank pulley outer....its about 2 o'clock iirc.  If not you can get a pretty accurate TDC position by putting a rod through No 1 plug hole and feel for the piston rising (I use a bike spoke) as you get near TDC there is very little movement of the piston for a lot of crank rotation, with practice you can sense when the piston stops rising and when it starts going down again, note where the crank notch is at these points and repeat it until you have a consistant result, TDC is mid way between the two points. This will give you somewhere to check the valve timing from.

The spark plug photos look like there is a lot of oil about, there is none on the plug body so its not come from the cam cover as you removed them so I wonder if someone has put oil in the cylinders to diagnose leaking piston rings??

Your story of what was going on when you went to collect it suggests to me that a bodger has been at it (not the skilled woodsman type) I wouldnt take anything for granted on this car, you will have to check everything starting with the basics so get the head off and have a peep inside.

Do a survey of the whole car for defects and cost the repairs, be realistic on its condition and value if you can get it to A1 condition then you should be able to decide if its worth the effort and cost.

[JamesV6CDX]

Looks to me, like I'll be ripping off the LPG and scrapping the car.

I'm not convinced that someone has been putting oil in the bores though.. on the basis that they were a bunch of muppets, and wouldn't have the knowledge that a bit of oil in the bore would temporarily increase a compression reading hence pointing to shagged piston rings.

I would love to know where the oil came from.

Guys, thanks for the comments, I agree with them.

Mark, before I make a decision on what to do, any chance you could also cast an opinion on this please?

[Markjay]

...The lack of pressure on 1 & 2 could be a seriously blown gasket...

Lack of compression on two adjacent cylinders could mean HG failure between the two i.e. at the thinnest point.

[JamesV6CDX]

...The lack of pressure on 1 & 2 could be a seriously blown gasket...

Lack of compression on two adjacent cylinders could mean HG failure between the two i.e. at the thinnest point.

This is what I'm wondering.. however I'm still stuck for an explanation of why the plugs are all soaked in what looks pretty much like oil.

[Marks DTM Calib]

Sounds like classic bent valves....

You will need to find an old imperial socket and knock it onto the buggered bolts to get them off the crank pulley....

The oil like substance might be fuel and carbon mix (there will be carbon in the cylidners and the fuel would dissolve some of it).

I would lift the head.....you can then see the bores and any scooring due to ring damage and feel for a wear lip on the bore walls....even if you decide not to fix it then it will be easier to remove the LPG kit with the head and inlet etc sat on the bench...

[JamesV6CDX]

I had a perfectly good 2.0 head sat at my mums

I gave it away a couple of weeks ago      

[tunnie]

I had a perfectly good 2.0 head sat at my mums

I gave it away a couple of weeks ago      

Thats a bugger!  

There are some 2.0's in the scrappy here if that's of interest?

[JamesV6CDX]

I had a perfectly good 2.0 head sat at my mums

I gave it away a couple of weeks ago      

Thats a bugger!  

There are some 2.0's in the scrappy here if that's of interest?

Yes! How much for a head do you reckon? If cost reasonable, Fancy accompanying me to remove one?  

[tunnie]

I had a perfectly good 2.0 head sat at my mums

I gave it away a couple of weeks ago      

Thats a bugger!  

There are some 2.0's in the scrappy here if that's of interest?

Yes! How much for a head do you reckon? If cost reasonable, Fancy accompanying me to remove one?  

Gladly   However your other post indicated you wanted it in the next 24hrs? (i am still at Uni) going home Friday night - Not sure how much most things are usually most things are a tenner!!

Maybe £20 / £30 ?? not really sure never taken anything that large out before... often you can hangle a big say... ah bugger only got a score on me will that do?  

[JamesV6CDX]

No no, not a huge rush, I just wanted the post in general chat for 24 hours!

I'm off next Monday, so would be a prime time I guess, that sort of money is OK, if we could blag one for £20 then we're laughing.

Wouldn't have to be nice to the car in the scrappy, as long as the head was removed carefully, all the other components could literally be butchered off....

[tunnie]

its always sods law with scrappy you see a nice Omega with bits you want, you either have no money or no tools, when you come back a week later the part has gone or its been trashed.

I know there are 2 good 2.0 engines in there, one a '96 N CD another is a mini-f '98 R CD..

[Martin_1962]

Tunnie has big pockets remember

[Marks DTM Calib]

Get the head off first....no point in re-placing it if the bores are buggered......

[JamesV6CDX]

Get the head off first....no point in re-placing it if the bores are buggered......

Not bothering mate

I've got a new Omega for the LPG kit now with 12 months MOT...