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Brand New Motor...blown!?!?

  • Thread starter Thread starter bhoove40
  • Start date Start date Jul 16, 2017
B

bhoove40

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May 3, 2015
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Jul 16, 2017
#1
  • Jul 16, 2017
  • #1
Hello all, this is my second post here following up my question about a sputtering engine.

I purchased a rebuilt 302 from a family friend that had it laying around at their shop. I put the motor in and put in a manual oil pressure sensor, and a copper wire thermostat; This is a 195 degree thermostat. I used 10-40W non synthetic oil to break in the engine, i put the recommended 5 quarts and it was all lining up. I started the car and let it idle at 1600 RPS for roughly 25 minutes to allow the cam to break in. After that i checked all the fluid in the car and what not. The temperature was roughly 200 degrees which is nearing the end of my comfort zone. I put the car in time, by feel of hand and not with a timing light. I drove the car lightly down the road a few times just monitoring my oil pressure and temperature.

At this point i'm extremely stoked, thinking wow this is awesome, all this time and money has been well spent and the car sounds awesome. I checked for leaks one more time after this and checked my oil. I added a little bit of coolant as only half the radiator was full. I drove into town never exceeding 3000 RPMS, and if i did it was maybe once or twice in first gear. Not whole shots or anything wild, just driving the car with traffic. I filled up with gas and proceeded on my way, oil pressure around 55 pounds, 41 pounds of fuel and around 196 degrees. After a stop sign shifting from first to second gear i hear the unthinkable.

"CCCCCCRRRRRRRRRRRRRRRSSSSHHHHH-- buh buh and then the motor shut off.

I instantly thought my distributor came loose but opened the hood to see it locked down in the same place. I pulled the radiator cap off and noticed it was roughly half full. But i was monitoring my gauges and i never exceeded 197 degrees.


As i'm sitting in udder disgust i can't help but thinking, WHAT WENT WRONG!? I never lost oil pressure, the car was not over heating or making any prior sounds that would lead me to even imaging this happening.

So what do you think could of happened?

Question 1: If the motor over heated and the pistons seized why would it do this after 21 miles of driving while going 15 miles an hour? Not when i was in 2nd gear pulling to 3000 rpm going 45 5 miles before this?

Question 2: Could being out of time really make a motor seize like this?

Question 3: Is 190 degrees too warm for a break in on a 302?

I can't believe it happened, but it did.... Nothing like a good 3000 down the drain.
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Jul 16, 2017
#2
  • Jul 16, 2017
  • #2
did you prime the motor before startup
the oil pump shaft could have snapped
sounds like you did not burp the coolant system
why did you need to break in the cam unless it was not a roller
197 degrees is fine- you have a 195 stat
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
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Jul 16, 2017
#3
  • Jul 16, 2017
  • #3
So is the motor completely seized? It's hard to believe that it would have locked up with the temp and oil pressure normal.
 

Mustang5L5

That is…until I whipped out my Bissell
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Jul 16, 2017
#4
  • Jul 16, 2017
  • #4
Drain the oil, see if you see any metal or anything strange inside.

Pull the plugs, see if you can turn motor over by hand

Pull dist out and see if the oil pump drive shaft twisted off and broke

And 200 degrees is fine for a modern EFI engine. I'd probably start getting nervous around 210
 

General karthief

wonder how much it would cost to ship you a pair
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Jul 16, 2017
#5
  • Jul 16, 2017
  • #5
Really hard to say what went wrong without being there, do like suggested above, also keep in mind that it may not be the engine, clutch, trans failures can lock up things too.
Keep us informed.
 
B

bhoove40

New Member
May 3, 2015
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Jul 16, 2017
#6
  • Jul 16, 2017
  • #6
mikestang63 said:
did you prime the motor before startup
the oil pump shaft could have snapped
sounds like you did not burp the coolant system
why did you need to break in the cam unless it was not a roller
197 degrees is fine- you have a 195 stat
Click to expand...
Yes i primed the motor with a drill until i saw it come to the valve covers. The cam was not a roller, it was a faced cam.
 
B

bhoove40

New Member
May 3, 2015
7
0
1
Jul 16, 2017
#7
  • Jul 16, 2017
  • #7
karthief said:
Really hard to say what went wrong without being there, do like suggested above, also keep in mind that it may not be the engine, clutch, trans failures can lock up things too.
Keep us informed.
Click to expand...
I checked the bellhousing for a huge chunk missing but it was completely intact. The clutch is brand new and is also all still in one piece. I'll be pulling some parts off it to really get a better idea of what happened today.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
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Jul 16, 2017
#8
  • Jul 16, 2017
  • #8
What is a faced cam?
 

jrichker

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Jul 16, 2017
#9
  • Jul 16, 2017
  • #9
Did the rear wheels lock up solid when the engine quit running? with a manual transmission, a seized engine would have done just that. There would be skid marks on the payment just like you stood on the brakes

Remove all the spark plugs and examine them. Did you find anything that indicates something unusual?

While you have the plugs out, does the engine turn over when you use a breaker bar on the harmonic balancer bolt with the transmission in neutral? Yes/no?
Can you rock the car with it in 5th gear and see the engine turn? Yes/no
 
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