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Mustang Motor Replacement Problems

  • Thread starter Thread starter bradlee
  • Start date Start date Sep 10, 2013
B

bradlee

New Member
Sep 10, 2013
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Sep 10, 2013
#1
  • Sep 10, 2013
  • #1
Ok so i just figured out after buying my 1991 mustang with a 5.0 motor 3 days ago that the 3rd cylinder hole from the back on driver side has only 10psi and didnt even bother checking the 2 after it towards the rear but the other 5 i checked were still good around 160-170 psi anyways i put oil in it 2 times and let it idle and it still has only 10psi so it must have a hole in piston or bad rings which either way i couldnt fix either so im looking at what it will cost to swap another 5.0 into it and i can find stock ones around just $500 so i might buy a 302 bored to 306 for a little more and i was wondering what are the things that are hard to do when removing an installing the motors?
Also if i buy a motor with all the cables attached etc, then im guessing the only wires and stuff i have to mess with will be the ones going throught the firewall and brake booster etc easy stuff correct? It will be my first time swapping a motor so please go easy on me as im ready to do it so dont wanna hear take it to a mechanic, because i can do this thanks.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,347
18,082
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Massachusetts
Sep 10, 2013
#2
  • Sep 10, 2013
  • #2
Could be a bad head gasket. Have you pulled the head? Is there coolant in the oil or oil in the coolant.

The gasket could also have popped between two cylinders.


Sent from my iPhone 4S using Tapatalk
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
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In the garage
Sep 11, 2013
#3
  • Sep 11, 2013
  • #3
Does it burn oil, have oil and coolant mixed together in either the radiator or oil pan, what do the plugs look like, what color smoke out of the tailpipe.

Finish doing the compression test on all cylinders, then time to pull the heads and see the damage.

Best value it getting a JY explorer engine and swapping out the cam, either TFS or Alex's valve springs,your stock distributor for a 5.0 HO and you have a GT40 motor that will put out about 260hp.
 
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