# engine temp



## Topkat (Sep 9, 2010)

During my 20 minute 2000 RPM cam break in. The motor temp came up slowely to 1/2. then in a few minutes shot up to 7/8 hot.
I put a fan in front of the radiator and that brought the temp down to an average of around 3/4 hot.
The front of the rad. never got hot,even before the fan.
The motor sure seemed hot. tho it never overheated.
I realize this event wouldnt really occur during a regular drive.
It just makes me nervous how hot the motor got.
I did notice that the fan shroud dosnt even barely cover 1/2 of the fan blades as viewed from the side of the car. Is this normal?
Do these Beasts always run so hot?
What can be done?
thanks as always


----------



## likethat (Oct 5, 2007)

When I break in an engine I don't run a thermostat. The largest fan that can be ran in the shroud would be best. What was the temperature around (outside/ or in the garage) the car when it was running? I would run a clucth fan myself.


----------



## jetstang (Nov 5, 2008)

Did you refill the radiator after the thermostat opened?? You must run the engine with the rad cap off til the stat opens, then refill til it's full, even during break in.


----------



## Topkat (Sep 9, 2010)

It was in the low 50's.
no I didnt open the rad.


----------



## geeteeohguy (Feb 2, 2008)

Your fan is fine.....should be about 1/2 in, 1/2 out of the shroud. I had the new T stat stick closed when I redid my '67 in '88 on the cam break-in. No damage done, but I was upset. I think the advice of no T stat during initial fire up and break in is good advice. The fact that you had a hot block and a cold radiator tells me you had an air pocket or just poor or late coolant circulation due to a balky T stat. When cool, pull the rad cap and fill the rad to about an inch or so below the filler hole. Don't fill it up all the way....the coolant will expand and boil out, syphoning a lot of good coolant out. Good luck.


----------



## BearGFR (Aug 25, 2008)

Hey Top,

It's normal for a new motor to run on the hot side during break in, that's one of the reasons the folks who make headers coatings say NOT to use them to break in a new motor. They get hot enough to damage the coating.

Also, the fan half in, half out of the shroud sounds like a perfect fit - that's exactly what you want.

That said, though, I'd be concerned that the radiator didn't get warm. That smacks of a stuck thermostat, lazy water pump, extremely low coolant level, or something(s) else that needs to be "figgered out" and understood.

Follow the suggestions already given to make sure you've got the cooling system full, then try 'er again to see what happens.

Bear


----------



## Topkat (Sep 9, 2010)

thanks guys..I neglected to say that the top of the rad. was as hot as everything else.
It was the front of the rad. that never got hot............
ty


----------



## chin (Jan 5, 2011)

I've heard of people drilling a really small hole in their thermostat around the edge so that air pockets geeteeohguy was talking about have a way to seep out. Anyone ever done that?


----------



## geeteeohguy (Feb 2, 2008)

Yes. I've also stuck an aspirin tablet in the t stat to hold it open on an initial fill. The aspirin dissolves leaving no trace and it makes the job a little easier....be sure not to **** the stat too much or tweek it.


----------



## BearGFR (Aug 25, 2008)

chin said:


> I've heard of people drilling a really small hole in their thermostat around the edge so that air pockets geeteeohguy was talking about have a way to seep out. Anyone ever done that?


I have, it works great.

Bear


----------

