Stumped: Vibration after engine replacement.

bigfords · Nov 25, 2016

Hey guys I got another issue I'm stumped on. I just installed a used 7.3 engine in a customer's 2001 F350 that has 300,000+ miles on it. The engine came out of a good friends truck, and ran great when it came out and has about 150,000 miles on it. He bought an engine of another PSA member on here that was rebuilt, balance, studded, etc.

Here's the deal, at idle the truck vibrates/drones. Almost like the engine mounts are shot or the exhaust is rubbing on the frame. Engine/trans vibration is being felt throughout the truck. You can really feel it resonate out through the front bumper if you put your hand on it. It will actually vibrate the bumper to where you can hear it.

The only other thing that may be related is that when the engine cranks over with the starter, it is unusually loud. Like something isn't right.

Any thoughts? I'm leaning in the direction of torque converter or flywheel. Just don't know what exactly. The truck has a bad drone to it in the cab.

Thanks for any input!

Magnum PD · Nov 25, 2016

Flywheel was put on at right location, correct?

bigfords · Nov 25, 2016

The crank has a dowel pin, i beleive it only goes on one way.

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Luke@MillerPerformance · Nov 25, 2016

bigfords said:
The crank has a dowel pin, i beleive it only goes on one way.

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Auto or manual trans?

Magnum PD · Nov 25, 2016

As long as the dowel was there.

ghohouston · Nov 25, 2016

Does it have a 4" downpipe? If so, definitely check it. If it is an auto, i would also definitely check the flexplate for cracking. If the flexplate was used to "pull" the transmission towards the motor, it cracks them.

sootie · Nov 26, 2016

Separate the motor from the trans and run it.

bigfords · Nov 26, 2016

Should have clarified...flexplate. Auto trans. Stock exhaust which is not touching anything. Ive crawled all over this thing lol.
Ill have to try separating them and running it. I need to take a better look at that flex plate too.

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ford_trck · Nov 26, 2016

If the engine was a very early 99 they have a sound that drives me nuts like something is rubbing or something. And the starter has a different sound also.

bigfords · Nov 26, 2016

Its a 2001 engine.

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lincolnlocker · Nov 26, 2016

ford_trck said:
If the engine was a very early 99 they have a sound that drives me nuts like something is rubbing or something. And the starter has a different sound also.

that shouldn't happen and you have chit ***ed up too..

OP
I am betting either flex plate or converter issues.. does it sound like a coffee can with marbles rolling around in it?

live life full throttle

god bless america and the farmer who feeds your fat ass

ford_trck · Nov 26, 2016

bigfords said:
Its a 2001 engine.

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Then don't worry about what I said

ford_trck · Nov 26, 2016

lincolnlocker said:
that shouldn't happen and you have chit ***ed up too..

I have only heard it only on factory automatic trucks. Every time I have looked at the truck they have been early 98 build dates and bone stock.

lincolnlocker · Nov 26, 2016

ford_trck said:
I have only heard it only on factory automatic trucks. Every time I have looked at the truck they have been early 98 build dates and bone stock.

yeah.. they all had flex plate or lots had converter issues..

live life full throttle

god bless america and the farmer who feeds your fat ass

bigfords · Nov 27, 2016

No noise like marbles in the converter. Just vibration/droning in the cab, bad.

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lincolnlocker · Nov 27, 2016

bigfords said:
No noise like marbles in the converter. Just vibration/droning in the cab, bad.

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prolly a pipe rubbing then

live life full throttle

god bless america and the farmer who feeds your fat ass

bigfords · Dec 12, 2016

Well to close this thread I finally figured out the vibration the other week. After I replaced the flexplate, I ran the engine without the trans attached and it still vibrated bad.
Eventually figured out that when i replaced the engine, I put the passenger side engine mount on upside down!! unbelievable. It goes on either way, and even looks pretty much the same either direction, but there IS a difference. The driver side says UP on the up side, but the passenger side was too rusty if it said any thing
Lesson learned..

ja_cain · Dec 19, 2016

bigfords said:
Well to close this thread I finally figured out the vibration the other week. After I replaced the flexplate, I ran the engine without the trans attached and it still vibrated bad.
Eventually figured out that when i replaced the engine, I put the passenger side engine mount on upside down!! unbelievable. It goes on either way, and even looks pretty much the same either direction, but there IS a difference. The driver side says UP on the up side, but the passenger side was too rusty if it said any thing
Lesson learned..

Good stuff. Lol! Thanks a bunch for updating the thread.

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