35k cracked block

[Blue Moon Sonic]

I still don't get how normal operating temps are between 217-224. I'm usually sitting between 192-212 on the 1.4 depending if i'm running it hard or just cruising. Does the 1.8 run that much hotter or should it be the opposite.

 

[River_Rat]

You are Trifecta tuned (according to your build thread, anyway). Trifecta lowers the operating temp to roughly 200 degrees.

 

[Blue Moon Sonic]

That makes a lot more sense. I was wondering on that one. Didn't get my UC until after I was tuned so I never knew what the stock operating temps were. Good to know.

 

[mitdr774]

The only good thing about when I was canned tuned was the lower operating temp. HPT wont allow me to correct it in my 1.8 though.

 

[kevjam79]

Another reason to run high octane and run a tune. Maybe Trifecta can take a little time and look into this for the 1.8s...

Sent from my KFTT using Tapatalk

 

[mitdr774]

The only good thing about the trifecta tune I had was that it dropped my operating temp to about 195.

 

[ChrisJ]

And at 260 your engine is toast. On my short list is a boost gauge and a temp gauge. My other car has an oil light that comes on at 4psi. 4! If my engine has 4 psi of oil pressure, it's already toast. My if Chevy (iron block/aluminum head motor) gets to 260 degrees, it's already toast too.

Your engine is "toast" as you put it if you start to boil the water and develop gas pockets which will cause hot spots.

The Sonic's cooling system runs a 20 PSG cap which means the boiling point of around 234F with plain water, no antifreeze. With Antifreeze it's around 275F.

So, the light comes on @ 255 and the coolant doesn't boil until 275F.


The Sonic runs hot and it's intentional. This is why the cooling system uses a 20PSIG cap rather than a 14 or 16 like older cars.

And mitdr774, I don't know that a tune dropping your temp to 195f is a good thing. I assume they did it so they could increase boost more without risking knocking but what negative effects can it have?

 

[mitdr774]

Dex-cool has had issues with breaking down at temps of 225 and up. Until fairly recently cars ran at 195*F. Higher temps allow for more efficient combustion and lower emissions from what I remember. Cant turn up boost if you dont have any.

 

[ChrisJ]

Dex-cool has had issues with breaking down at temps of 225 and up. Until fairly recently cars ran at 195*F. Higher temps allow for more efficient combustion and lower emissions from what I remember. Cant turn up boost if you dont have any.

I had a 95 Lumina whos second fan didn't kick on until around 230-235 or so.
Never had issues with the Dexcool breaking down even after 130,000 miles.

Then again, I made sure the system was always full. Only issues I ever heard about with Dex was air in the system.

Now that said, Dex has had changes over the years and being GM was the one that developed it, do you think they would be putting it in cars that cause it to break down after having had it in service for 20 years now? Seems a bit odd....

 

[laborsmith]

I had a 95 Lumina whos second fan didn't kick on until around 230-235 or so.
Never had issues with the Dexcool breaking down even after 130,000 miles.

Then again, I made sure the system was always full. Only issues I ever heard about with Dex was air in the system.

Now that said, Dex has had changes over the years and being GM was the one that developed it, do you think they would be putting it in cars that cause it to break down after having had it in service for 20 years now? Seems a bit odd....

That is not how I read Clyde's comment.

Chevy is using 220* across the board to improve emission and fuel economy numbers. They say they do for those reasons and in truth they are correct.

I know one can go too low, but 195 to 200 seems to me the equivalent of 170 to 180 when the coolant temp could be changed simply by changing the radiator cap.


Laborsmith

 

[LTZ ICE]

I don't care what you drive, every manufacturer has their share of cracked blocks and heads.
As far as the high engine temps, that's why I use Mobil1 Fully Synthetic in my 1.4T. With these operating temps, conventional oils just don't hold up like a good synthetic. I feel it is worth the extra $$ for peace of mind.

 

[Z71]

I am not very thrilled to read all this. I am at 34.5 k miles on my Sonic. Fortunately no issues so far.

Are you sure this engine has a cast iron block? Most small engines like these are all aluminum block and head.

 

[$ub$onic]

I am not very thrilled to read all this. I am at 34.5 k miles on my Sonic. Fortunately no issues so far.

Are you sure this engine has a cast iron block? Most small engines like these are all aluminum block and head.

1.8 is Iron block, aluminum head.

 

[mitdr774]

Iron block, 63.5K miles in and no cracked block.

 

[ChrisJ]

It's a bit redicules to read this thread and say you're not thrilled.

I wonder how many 1.8s have been made, or rather, how many family 1 engines have been made world wide since the 1990s? And how many of them have cracked blocks?

There are 1920s-30s Model A blocks that cracked as well over the years but most did not.

When there are literally hundreds of thousands of an engine and even 100 crack, it's such a small percentage it doesn't even matter. How many are in this thread because I didn't even look, one, two? Who cares!?

Get some ****ing perspective. Seriously.

 

[Hdmanny]

Almost 80k on my 1.8 and I have using Mobil1 for about half that mileage.

 

[Z71]

It's a bit redicules to read this thread and say you're not thrilled.

I wonder how many 1.8s have been made, or rather, how many family 1 engines have been made world wide since the 1990s? And how many of them have cracked blocks?

There are 1920s-30s Model A blocks that cracked as well over the years but most did not.

When there are literally hundreds of thousands of an engine and even 100 crack, it's such a small percentage it doesn't even matter. How many are in this thread because I didn't even look, one, two? Who cares!?

Get some ****ing perspective. Seriously.

Why is it ridiculous? This is a cheap car from GM and lately GM quality control has been slipping badly. Just read the GM truck forums if you want to know how good the 2014 trucks are. If GM let quality of their biggest money making vehicles costing around $ 40-45k slip so bad, then what can one expect out of a $ 16k car?

If they had eliminated certain quality control checks on block castings that previously helped uncover hidden cracks, then all bets are off.