Do new engines run hotter?

[Clyde9]

From: Moesyn  (Original Message)
Sent: 3/7/2008 3:03 AM

Is it a myth that engines run hotter while they are breaking it? I am wondering why my water temp gauge is reading higher on my newly rebuilt 440-4 than it was before the rebuild. The sending unit is the same.

Over the weekend I'll be installing a Sunpro water temp gauge so I'll have a sense of the actual temperature. It is frustrating trying to decrypt what the needle going up to the "E" on a grade means!



From: denisondc
Sent: 3/7/2008 7:58 AM

I replied to your other post on this. I imagine a new engine might want to run slightly hotter, but the thermostat is supposed to control the coolant temperature, so you wouldn't see any difference. You could also try a new sender unit. I have had two of them go bad over the years. One began indicating higher and higher temperatures - due to old age I guess. But the other one in the same place in the same engine went bad by indicating lower and lower temperatures - I guess because the terminal where the wire connected had worked loose from the element inside the sensor.
I also installed a mechanical water temp gauge. It was a very good use of my time, as was the mechanical oil pressure gauge I installed.



From: killme10
Sent: 3/7/2008 11:46 AM


Hi, Yes new engines run hotter. Friction is the problem but it will come back to normal after you break it in. About 500 miles and you will notice a difference. It's just new rings & bearings wearing in to the newly honed cylinders and bearing surfaces. You will also notice more horsepower the more you drive it. The engine probable turns over slower than it did before all due to friction. That will go away too. Be sure to change your oil and filter after 500 miles and then at 1500 miles. Marty