2016 Mustang GT Ticking issue

[spogshd]

Gt pony, you could be hitting the nail here, sounds like its a plausible cause.

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[spogshd]

Do we know how wide the journal should be and what the tolerance is on the width.

 

[GT Pony]

Do we know how wide the journal should be and what the tolerance is on the width.

Nothing is the shop manual that shows what the width of the crank journal should be. That's on some Ford manufacturing drawing someplace.

Also, I misspoke earlier. The big end rod bearings don't have skirts on them like some bearings do to control side clearance. So the rod end side clearance is also dependent on the exact width of the rod's big end themselves. When all this stuff is assembled, the total clearance (gap at red arrow) should be within the specs I posted earlier.

 

[HermanGerman]

Sure sounds like it could be the source. Is that a rod bearing he's moving back and forth on the crank journal? Any other rods do it?

would the engine not blow within days , with a rod bearing like this?

 

[spogshd]

This could explain the wear in the cylinders that has be noticed on some short blocks that have been replaced right,

 

[Turbolag87]

interesting find thats for sure. MY 18 has 1700miles on it and quiet as hell (so far)

 

[kenand1988]

Quick update:

The short block is going in but the OPG arrived with damage. There some chips on the outer edge of the gear housing. I contacted LMR and they are processing the return. I'm moving on without it right now and just having the crank spline replaced with the a/m one. This is at no cost. If I were to wait for LMR it wouldn't be till Friday or Monday before ANY more work can be done on the car. It's been 3 weeks, im sick of waiting. I will most likely install it myself down the road if I decide to s/c the motor.

The service advisor stated the car doesn't look like it'll be all back together today. I've asked the service manager if the tech inspected and measured the crankshaft and rod bearings, and the journals on the crankshaft. I'll post back with the answer on that. Given that tech is already installing the new motor I'm suspicious on how much they actually looked over the old motor.

 

[GT Pony]

would the engine not blow within days , with a rod bearing like this?

Radial bearing clearance between the crankshaft journal and rod bearing is different than the rod side-to-side clearance that is shown in the figure I posted above with the red arrow.

 

[GT Pony]

This could explain the wear in the cylinders that has be noticed on some short blocks that have been replaced right,

I think the cylinder wear in the 2018 might be a separate issue from the "BBQ Tick" - maybe stemming from the cylinder spray liner or manufacturing process, or even from too much piston to cylinder clearance. This loose rod side clearance could be the root cause of the BBQ Tick, but doubt it's related to the 2018 cylinder wear issue.

Lots of stuff can go haywire between parts when the clearances are not within specifications. Ford or any other car company can have the best engineering drawings on Earth, but if manufacturing doesn't make parts to the drawing specs then problems like this can happen.

I don't think side-to-side rod movement could cause cylinder damage because the rod is also moving on the piston pin, so the piston really doesn't see any force from this rod movement. It's too much movement from too much rod side-to-side clearance, and given the right RPM that could certainly cause the rods to move while running and cause a ticking noise like heard with engines with the "BBQ Tick" sound.

I can see why Ford just orders up a short block to fix this, because it's probably cheaper than replacing a badly machined crankshaft and/or rods that are out of dimension specifications.

 

[kenand1988]

It's too much movement from too much rod

heh

 

[GT Pony]

It's too much movement from too much rod...

heh

Could be another clearance issue ... LoL.

 

[kenand1988]

From: Robert
Sent: Monday, August 13, 2018 2:50 PM
To: Davidson
Subject: RE: RE: Mustang

Yes, no abnormal wear on bearings, crank, pistons or cylinder


From: Davidson
Sent: Monday, August 13, 2018 2:53 PM
To: Robert
Subject: RE: RE: Mustang


Were the rod bearings within tolerance?


Found this video that is intriguing. The rod bearing(s) seem to be out of clearance and make a very similar sound to the one present when I brought in the car.



From: Robert
Sent: Monday, August 13, 2018 2:43 PM
To: Davidson
Subject: RE: RE: Mustang


Nothing of interest in the old engine except cylinder 3 had less carbon on the piston. That’s the cylinder that lessened the noise when cancelled.

 

[GT Pony]

From: Robert
Sent: Monday, August 13, 2018 2:50 PM
To: Davidson
Subject: RE: RE: Mustang

Yes, no abnormal wear on bearings, crank, pistons or cylinder.

It's possible to have too much rod side clearance and no abnormal wear on the bearings or crankshaft.

 

[kenand1988]

It's possible to have too much rod side clearance and no abnormal wear on the bearings or crankshaft.

I don't think they measured that and I don't think they will. They have what they need to get paid by Ford. But your thoughts on the underlying issue are promising.

Edit:

we have a better shot getting CEHOLLIER to ask his mechanic to measure that.

 

[GT Pony]

I don't think they measured that and I don't think they will. They have what they need to get paid by Ford. But your thoughts on the underlying issue are promising.

Edit:

we have a better shot getting CEHOLLIER to ask his mechanic to measure that.

It's amazing that this excessive rod side clearance hasn't surfaced until now. Seems these Ford dealers aren't told to make measurements, but to just send in the bad short block back to Ford. Now that we are getting information from Ford techs that will actually make measurements, the story might be clearing up to the real root cause of the BBQ Tick noise.

I'm curious if all these ticking engines have excessive rod side clearance, and if so is it always the same two piston rods .... meaning, is that journal on the crankshaft always possibly machined incorrectly (too wide?) for some reason?

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