tevbax

Okay, heres my deal for the day. I took the car to my local import shop for the diag of my misfire. Turns out the head gasket was leaking coolant into the #2 cylinder, causing the misfire. So, they took the head off, machined .045" off of it to true it up for install. Then, they measured the block. The block is presenting a .005" warpage!!!! The shop said they had been doubting the "trueness" of the flat bar, and sent it out to be remachined.

So heres my dilema. The C230 (04) has 58k miles on it. Its at an independent right now. If the block is warped, do i take it over to the Dealer for possible warranty consideration? I have seen plenty of warped heads in my life, but NEVER a warped block, especially at such a young age. Its never been overheated.

Any info/advise would be greatly appreciated. I have all the faith in the world in the shop that is working on it...... but a block machine job is going to be BIG money!

:w all:
: smash:

Glyn M Ruck

I seriously doubt a warped block. Someone dropped the straightedge. What I would believe is an errosion low spot if the head gasket was seriously blown & it had been driven that way.

SeaCoupe

Another odd question from someone with a low post count.

SickSpeedMonte

All while doubting the strait edge?

I hope you didn't get screwed here. That will increase your compression ratio, and I dont know about the valve/piston tolerance on these motors stock, but I have heard as low as 0.040" before on some motors.

tevbax

First off, let me correct my numbers. The shop thats doing the work sent out the head to the machine shop. Completely independent measurment device here. .0045 is what it should have read.

Second, the DECK is warped, not the block. The frustration is setting in a little.

tevbax

Are you kidding??

Glyn M Ruck

Please excuse my ignorance. Terminology varies around the world. What exactly do you mean by the "DECK" is warped?

SickSpeedMonte

The block surface that mates to the head is the deck. I dont see it being warped, but I agree that there may be some erosion.

Did they tell you how far off the deck is? i.e. how thick of a feeler gauge they can get in there? I'm sure there is a bit of a tolerance that the head gasket can absorb if we are talking in the 0.001" magnitude

Glyn M Ruck

Right - thanks - hence centre of crank to deck height measurement in American speak. So he is trying to say the block is warped.

tevbax

Right, the deck is what the the head mounts to, with the head gasket squished under it. Theyre talking more like .005 warpage.... as it does not look like erosion.

Glyn M Ruck

Get it re measured by someone else. The next thing they will tell you is that it needs to be line bored.

tevbax

i think im gonna head out of work early today and go measure it myself.

mleskovar

Lots of BIG problems with the 4 bangers. Super charging definitely takes it's toll on an engine. I would pursue MB help with this.

Glyn M Ruck

Mleskovar - the problem is they pushed the M271 too far for the American market to continue calling it a C230 - in C180 & C200 trim it's a vastly more reliable engine - But bigger blower & a chipped ECU to achieve the extra horses & less than ideal fuel make it fragile.

Glyn M Ruck

I see Ed lurking at the bottom of my screen & he is probably fed up with me for getting cross with Todd. Yes - The M111 is a far stronger engine at this kind of power output or more.

SeaCoupe

Glyn,

No I saw the humor in the banter. I'll never pretend that the M111 isn't a bit of a throwback with regards to sound. But in US trim it is oh so tuneable. At under 2,700 rpm, I can easily get 30mpg or more out of the car. My avg is 26.7. That is because I do a bit of city driving and of course the mileage suffers.

In any case, to the origional poster, my bad. I didn't put you together with your previous thread topics. I would recommend keeping everything together though.

I'm assuming that the head is aluminum and the block is iron? If so, it is the head that would have warpage.

Just my two cents.

E

Glyn M Ruck

Thanks for the understanding Regarding the block it is cast aluminium with NiCaSil bores like the 6 Cyl engines. Any skimming would have to be undertaken with great care so as not to lift the NiCaSil.

tevbax

Well, the verdict is in. Took the flat bar and measured .001 distortion on the top of the deck surface, which is deemed acceptable. Shes going back together.

At the end of the day, I think she still might be going in for a trade. The M271 has taught me my lesson.

Glyn M Ruck

.001 is nothing. Correctly torqued that will be fine. A lot of our Honda racing motorcycles with Aluminium alloy crankcases were designed to only pull true at correct torque. Buy a nice V6