Would running straight water be causing a slightly higher temp?
 

I've been running just water in the cooling system just for the motor break-in just to make sure I had no leaks so I wouldn't lose my expensive (to me lol) antifreeze. I was, and AM going to put the antifreeze in it of course but just had this question.

I'm not sure if it's because it's a freshly rebuilt motor, or because I'm running straight up water but the block and parts like intake/valve cover feel hotter than they did before the rebuild.

I'm using a good 180 degree thermostat, the temperature gauge never reads anymore than it did before the rebuild but I'm just running water at the present time, would this cause the block/parts mentioned to feel a tad hotter than normal?

Once again, I'm putting the antifreeze in it, just wanted to know if it was something else that may be causing the abnormal block heat. Other than me being crazy of course and just thinking it's hotter.

Thanks as always!

Re: Would running straight water be causing a slightly higher temp?
 

a fresh motor is going to be warmer any way because of the friction of the new motor breaking in,but yeah i would get antifreeze in there it helps with cooling and it also lubricates the water pump.

Re: Would running straight water be causing a slightly higher temp?
 

How long does it usually take for everything to break in, as this is my first ever rebuild I have nothing to compare too.

Re: Would running straight water be causing a slightly higher temp?
 

depending on tolerances, a motor can take anywhere from 500 to 1000 to "break-in". be careful with it, vary the rpms, no full throttle romps, change oil @ 500, no long periods of time @ idle.

piece of cake.

Re: Would running straight water be causing a slightly higher temp?
 

water cools better than antifreeze.

Re: Would running straight water be causing a slightly higher temp?
 

50% antifreeze mix boils at a higher temp than water, but I didn't think it cools any better. I agree that your somewhat higher temps are simply from having a new engine.

Re: Would running straight water be causing a slightly higher temp?
 

water transfers heat better that antifreeze.

Re: Would running straight water be causing a slightly higher temp?
 

Break in ?? Whats that ? lol

Re: Would running straight water be causing a slightly higher temp?
 

it rusts better with water

Re: Would running straight water be causing a slightly higher temp?
 

This. Water has a higher specific heat than mix.

Re: Would running straight water be causing a slightly higher temp?
 

Antifreeze has anti-corrosion agents in it. You need it.

Re: Would running straight water be causing a slightly higher temp?
 

Is you cooling water slightly rust-coloured? Mine is because I used too little coolant. Now I have rust-coloured antifreeze mix. Use an antifreeze mix even if it is not too strong of a mix. Any way to get rid of a the rust colour? It is difficult to drain ALL of the coolant.

Re: Would running straight water be causing a slightly higher temp?
 

Water also freezes....Water also changes states when it boils...:)


Alex,
If its that bad, you may have to do some serious flushing along with some parts replacement to get all the rust out.

Smitty

Re: Would running straight water be causing a slightly higher temp?
 

Guys I planned on running the 50/50 mix from day one, I was just doing water for the time being so I didn't waste antifreeze if I had any leaks. Thanks for everyones responses.

Re: Would running straight water be causing a slightly higher temp?
 

I have done the same thing. Just to check everything out, then replace with 50/50. Water will cool a bit better, but not WORK better. JUST DON'T FORGET!

Re: Would running straight water be causing a slightly higher temp?
 

In theory, water will cool better. However, in my observations, an engine with coolant will run a tick or two cooler.
If you are just going by "the valve covers seem hotter" then you can't tell. No one has a hand calibrated that closely.

Re: Would running straight water be causing a slightly higher temp?
 

Most antifreeze is also called antiboil. Its designed to raise the boiling point of water along with the pressure in the system created by agood radiator cap. I've also heard of overbored cylinders causing this... not sure though.

Re: Would running straight water be causing a slightly higher temp?
 

From what I understand nothing cools better than water. Water will not boil at 212 degrees being it is under pressure. Straight water dissipates heat best, better than antifreeze mix. But antifreeze has the anti corrosion prohibitors your system needs, as well as, you guessed it anti freeze properties (as you already knew).
Your engine is running hotter because it is new (as mentioned before). Water for break in should not be an issue.
I would not run it with tap water but, I would use distilled water and I would not go more than a couple of days before I would drain that an add the antifreeze.
When you say break in I would think you mean running it for 20-30 minutes to break in the cam.
Being in sunny so cal I like 70% distilled water and 30% antifreeze.
Good luck, huero.