I was able to find my Dads old 65 coupe with a 6 CYL. It was started to be restored and it looks like the motor had been rebuilt but not sure. What are the tell tale signs if this has been rebuilt and is there any way to start the motor or turn it over to see if its locked up? I'm debating keeping the 6 in it based on what I can find out.

 

Changing a 64-66 Mustag from 6 to 8 is a MAJOR project. You have to replace everything except the body. No kidding.

If the engine was rebuilt, the only way to be sure is by pulling the head and measuring the bore, std, 0.030 oversize, etc., not worth the trouble. Pull the plugs, and squirt some light oil, like Marvel Mystery oil etc. in each cyl. Leave it overnight, and turn it over the next day. If it turns and starts, or simply turns well, change the oil immediately using an engine flush such as Gunk.

 

if the motor has been rebuilt there should be some easy signs of the motor being apart. you should see stuff like fresh gaskets? or new soft plugs in the side of the block? you can try taking the oil pan off if the motor is on a stand and simply looking up at the pistons, if the motor was freshened and never run the piston bottoms should still look new. regardless, put a 15/16 socket on the front and try to spin the motor over(plugs out)..if it spins...chances are it will run whether it was rebuilt or not..

 

How to swap in a v8 http://www.mustangandfords.com/howto...ade/index.html

 

There are much simpler and less expensive ways to determine engine condition. Start with a compression test. If it holds good compression, doesn't make any strange noises and holds good oil pressure, that's all you need.

Those little sixes rebuild well and hold up well. If it ain't broke dont' fix it. The compression test and monitoring oil pressure will tell you if it ain't broke.

BTW, if you follow the above advice, MAKE SURE that you turn the engine over enough to blow out the MMO before replacing the spark plugs and start the engine. Leaving the MMO in the cylinders could result in major damage when it tries to compress the liquid.

 

True, but he wanted to know how to tell if it had been rebuilt. I have recently seen a 66 GT350H in restoration, when they opened the engine it became apparent that not only had it never been rebuilt, it didn't need to be.

Amazing, frankly, not just a 43 year old Shelby with a perfectly good engine, but a Shelby that started out as a rental car with a perfectly good engine.

 

Knowing whether or not it has been rebuilt is pointless. If the engine is in good shape, run it. Opening it up just to know if it has rebuilt offers no meaningful information.

If that Shelby had never been apart and didn't NEED to be apart, it's ashame to mess with it. Again, if it ain't broke, don't fix it.

 

you might break something that was fine before!

 

When you are doing this to a Shelby, ya pull the bearing caps and heads, too. Just to be sure.

 

Thanks Guy! It needs some paint and it should be good to go. Just need to fix the frame rails and it will be perfect...well