Laewoo Lanos 1999 1.4 Engin Problems

[Albertdup]

Hi

I have a weird problem, The breather pipe from the cam box teared and I did not noticed this , I do not fiddle with stuff if it works. I drive gravel roads frequently and dust got sucked into the engin. This caused the cam to block up and run dry. I noticed this when the engin began to sound like a diesel engin, the cam got dammaged and the rockers were worn. The cam and the cam box was relaced with new rockers etc. I am lucky to get original daweoo parts without a problem and therfore only use original parts from the dealers.

The thing is since the cam got replaced the idling of the car was wrong it seemed as if it was idling to slow, the whole engin seems to be shaking a bit. Fuel consumption increased and it did not have as much power as before the cam got replaced.

I took it to the dealership who did a compression test and said my no 3 compression is low. The head then got serviced and replaced the valves at no 3 on the head and put in new rings and bearings hidrolic lifters new rockers gaskets you name it and it was replaced even the electronic coil ignition and plug cables with new plugs. The thing is it still is idling wrong and have less compression at no 3 the data is.

no 1 2 3 4 in bar
13 11.5 8 13

this is slighty better than before they replaced everything.

The head was removed twice for testing and it tests OK no leak at valves at no 3.

I do not know what can be done any more. I have compared the cam with what they have for replacement now and it seem to be the same.

I need help please.

Thanks

[MMamdouh]

OK now... what happened to the engine is really dramatic, after changing all that stuff i can only suspect the block.

maybe the cylinder walls at the cyi. 3 are worn out by the dust and stuff the engine "inhaled" and corroded the walls that it can't keep pressure no more... OK you changed the rings but it won't help much if the walls are worn out.

MMamdouh

[Albertdup]

The walls of all the pistons was inspected during all of this and no scratches or damaged was observed. We are opening it up again tommorow to take another look. I am a very careful driver, a girl friend of mine complained that I am driving slower than her grandma.

Thanks

[MMamdouh]

Hmmm... cyilender pressure cmes from:

1) cylinder walls (inspected)
2) cylinders
3) Piston rings (changed)
4) Head Gasket
5) Intake valves (changed)
6) intake valves seats
7) exhaust valves (changed)
exhaust valves seats
9) spark plug threading

check all of those components and if all of them are OK then their is no way you have a lost compression on cyl 3.

wanna make sure your cylinder walls, piston and piston rings are OK?? pour some engine oil from the spark plug hole in cyl 3 (some 1/8 liter or so) then make the compression test, if the values are the same then it is something in the head... if not then it is the cyilendre walls, piston or piston rings.

MMamdouh

[Albertdup]

Hi Thanks for replying.

Whe did that earlier today poured some oil in through spark plug hole and the preasure increased dramatically. The Head Gasket was also replaced and the intake valves seats and exhaust valves seats on no 3 just to make sure .

Thanks

[MMamdouh]

pressure increase = failure at piston, piston rings or cylinder walls no doubt about that.

you said they checked the walls and they were OK but the oil test is saying otherwise... tomorrow make another check when you gut the engine, it doesn't have to be noticed by eye, make them measure the circularity of the chamber and chek if it turned somewhat oval, also inspect the piston itself (cracked or oval) and the rings (might have broke during installation or so)

anyways this shows that your head is OK and out of suspesion... your problem is in the lower part of hte engine not the head... make full use of gutting the engine tomorrow and inspect it very well.

MMamdouh

[Albertdup]

Hi

The low compression sleeve on no3 was checked and measured a wearing of of 1 thou was recorded. There does not seem to be any damage to the piston or the sleeve. All cylinders measures the same wear limit. On no 3 second compression ring shows no wear. No 3 top compression ring bedded nicely.

Yet problem is not resolved low compression on no 3.

Any help advice appreciated.
Albert

[GsiTurbo]

Another option is to do a blow-by test. A pressurised air line is attached to the engine via the spark plug opening, then measured compressed gas (usually air, with a die) is forced into the combustion chamber.

The leak can be traced by observation of coloured gas. One of the following may happen:

- coloured air visible thru the air filter assembly - leak in the cylinder head (intake valves)
- coloured air visible thru the exhaust manifold - leak in the cylinder head (exhaust valves)
- coloured air visible thru the breather connector to the cylinder head - leak thru the piston/rings

Hope this might help to source the problem.

I would also ensure the spark plug thread is clean when doing the compression test, as some of the air might simply escape through that area, thus causing an incorrect reading.

[Albertdup]

Hi

We have done a test as you have sugested, but did not notice a leak anywear. This is really driving me nuts. The air preasure we used was sufficient to turn the engin a number of times.

Thanks,

[MMamdouh]

WTF?? excuse me i don't usualy use this kinda laguage but this is really crazy

low compression on cyl. 3 = leak on cyl. 3
oil squirts fix leak problem= piston, piston rings, block problems
passing the die test = no leak whatsoever

HOW THE HELL DOES ALL THIS ADD UP TOGETHER??

frankly man i am confused here... as a last check, check the threading of the no. 3 cyl spark plug as tom said... maybe the compression tool leaked form their but hte die tool got better isolatio or so.

yet this still contradicts with the fact that the oil squirts\t fixed the problem... maybe some oil was leftover on the threading and caused the leak to go away... i just can't think of something better right now.



MMamdouh