Did Something Stupid To My 79 Cadillac 7.0 Engine

[crazyoildude]

I started up my old but in very good condition 79 Sedan de ville with the 7.0 litre after checking all the fluids i started it up and it was running rough because it was sitting for years in my garage. I let it warm up and went into the garage for about 10+ minutes,, when i went over to her she was overheating!
It turns out the thermostat did not open!
I am feeling pretty sick with an overactive thyroid and now a bad cold so i was not thinking. I took out the thermostat and am waiting for my parts guy to send me another thermostat and top hose. I really hope i did not do any real damage.. one good thing is i had new oil in her when it happened. I can take the heads off resurface them and put it back together but i hate to do that it was 100% original and in near mint condition with around 300,000 miles on her (she was my parents and when my dad died i got my mom a new car). I will know tomorrow or the next day if i get the parts.. I also noticed the thermostat was a 180 and not a 195 we must have changed it before..we had it since new.. What do you think?...

 

[tinmanSC]

Was it doing anything strange that caused you to go over to it or was it running normally, nothing strange?

 

[crazyoildude]

it started to steam up and leak anti freeze

 

[JHZR2]

Sorry to hear that. Was the needle solidly in the red? How long did it stay overheating before you shut it down?

The good thing is that it was idling, not under load, where the heat load would have been much higher.

And Im guessing that it was an all iron engine?

 

[J281v8]

Thermostat and a coolant change would be a good start. Also a new rad cap.

 

[crazyoildude]

it only has a coolant light and if the water does not touch the sensor it wont go on..

Yes it is an iron engine..

 

[crazyoildude]

im waiting for a thermostat and new top hose
My dad took such good care of this car with the exception of the 180 thermostat that i put in

 

[artificialist]

Many replacement thermostats are cheaply made, be sure you get a high quality one.

 

[spasm3]

Cast Iron engine, if it only ran 10 minutes it should be fine providing there was coolant in the heads. My guess is it barely got into the hot zone when you found it. If it was low on coolant and not much was in the heads, intake, you may have an issue. I have seen iron head v-8's overhead until they loose power at speed and almost seize, and later run fine. aluminum heads don't have that margin of error.

 

[crazyoildude]

i know this one was cheap but i went to the Cadillac dealer and the delco looked like junk!

 

[bama7x57]

Did it try to continue to run after you cut the switch off? An extremely hot, carbed engine will do that. If it turned off easily, I think you'll be in good shape.

 

[crazyoildude]

nope shut off as normal....I cant believe how much this bothers me...

 

[Jarlaxle]

Let it cool and you are probably fine.

 

[Errtt]

New stat, hose if needed, radiator cap, fill her up and see how she does. If okay, take a easy close drive keeping an eye on things before getting back to normal driving.
I vote it will be fine. You wasn't hauling down the freeway.

Keep an eye on both oil and coolant for a bit.

 

[JHZR2]

Test the new stat in boiling water before installing. Measure the temp it opens at. Some stats are fail open types. Likely a good choice.

 

[RH+G]

Dont worry bout it those motors dont blow headgaskets easily

 

[jsnyder49090]

i wouldnt worry i have done much worse it has to reach very high temps to do any real damage.A couple weeks ago i ran my van out of water i probably drove it 5 miles with nothing the smell told me something was wrong i shut her down and she was hot let me tell you.I had someone bring me some water and drove it home same as she always was.

 

[Stanley Rockafeller]

Originally Posted By: crazyoildude
nope shut off as normal....I cant believe how much this bothers me...


It's because your sick, that's why it bothers you so much.

When I was working on my cars when I used to suffer from colds etc. I noticed how any little problem with the car would totally send me off the edge. Sometimes it wasnt' even anything to do with cars, just other small, irrelevant stuff would have me constantly pining over it like it's something catastrophic.

 

[JimPghPA]

If you get a new radiator cap, get it from the dealer, and get the same pressure as original.

After market radiator caps not from the dealer are almost always at least one pound different than the original. You may not think one pound is a big deal, but it can cause problems.

You are much better off staying with a radiator cap with the same pressure rating as the original, and that would be the one sold by the dealer.

 

[Stanley Rockafeller]

Actually I have a MUCH worse situation that happened to me and my 97 Escort 4 or 5 years ago.

Shortly after I changed my timing belt, tensioner and water pump I was driving home on the freeway. Everything was going swimmingly when all of a sudden I noticed that when I got off the gas and put the car in neutral, the car wanted to die. Only after putting it back into gear and popping the clutch with the car coasting would it come back to life.

I pulled off the freeway and the car just died and didnt' wanna start. The temp guage didn't show any problems so I finally got the car running again and I drove the car the rest of the way home..bucking and backfiring the whole way. The car gave off some strange overheating smells too...boy that car was in trouble.

After getting home I went online to see what the problem could have been. Nobody could offer any assistance. After letting the car cool for about 3 or 4 hours I went out to it again and lo wanf behold the car started up and ran perfectly...not a single problem.

Turns out I overheated the car by not bleeding the air outta the system. The car eventually sucked the recovery tank dry while it was cooling down and everything was god again. Even by the following fall, there still was no probelms with the car...everything went back to normal.