f300 shut down problem

[bjd76]

Coming in from trip, running 3200 - 3600 rpms, port engine would run 2 to 22 minutes (most shut downs were at 5 or 10 min) and then shut down. starts right up. Action taken to date:
- Fuel water separators checked - no water or debris
- Visual check of fuel filter - no sediment, looks same as starboard (replacing both)
- Engine running voltage at 14.3v, engine off - battery at 10.6v (replacing)
- Engine running: temp, H2O pressure, battery register as normal
- mechanic checked vst filter - all ok
- mechanic noticed timing belt shredding, faulty tensioners/alignment (replacing)
5/14 manufacture, 6/14 install, 680 hours
Thoughts? (so far)
- faulty bulb primer (bad check valve)?

[sony224422]

How do your plugs look? Any stored codes?

[ausnoelm]

Didn't someone have the same motor that was shredding the timing belt, and it turned out to be something sinister? Rodbolt might remember, I think he posted on it.

[pstephens46]

Don't see many threads on F300s. This sounds interesting.

[rodbolt17]

is this a V8 300 or a V6 300 ?
the 4.2L v6 had some crankshaft thrust bearing issues.
that issue first shows up as a shredding timing belt.
make sure your dealership has a master tech and request that tech to work on your rig.
there are no adjustments for cam sprockets,idlers or the tensioner.
you align the belt at installation and it is there UNLESS something fails.
if the thrust bearing is failing the crank starts walking up and down.
this will start shredding a belt just before the crank snaps.

that belt can go thousands of hours unless its damaged.

[ausnoelm]

is this a V8 300 or a V6 300 ?
the 4.2L v6 had some crankshaft thrust bearing issues.
that issue first shows up as a shredding timing belt.
make sure your dealership has a master tech and request that tech to work on your rig.
there are no adjustments for cam sprockets,idlers or the tensioner.
you align the belt at installation and it is there UNLESS something fails.
if the thrust bearing is failing the crank starts walking up and down.
this will start shredding a belt just before the crank snaps.

that belt can go thousands of hours unless its damaged.

I thought I remembered something about the belt shredding that you posted that was rather dramatic if left unchecked.

[bjd76]

is this a V8 300 or a V6 300 ?
the 4.2L v6 had some crankshaft thrust bearing issues.
that issue first shows up as a shredding timing belt.
make sure your dealership has a master tech and request that tech to work on your rig.
there are no adjustments for cam sprockets,idlers or the tensioner.
you align the belt at installation and it is there UNLESS something fails.
if the thrust bearing is failing the crank starts walking up and down.
this will start shredding a belt just before the crank snaps.

that belt can go thousands of hours unless its damaged.

It is a v6, 4.2L. He is a certified master tech and I will pass your comments on to him. Thx.

[ausnoelm]

Surely he should know about the problem if he is a Master Tech?

[bjd76]

Surely he should know about the problem if he is a Master Tech?

I discussed it with him and he is familiar with the problem - not all shredded timing belts equate to thrust bearing problem/failure. Visual inspection did not reveal anything out of ordinary. It may be you're sitting on a time bomb but no way to know without taking apart engine and at the right time...

Advanced Maintenance Diagnostic registered as "01" - engine performance normal.

[ausnoelm]

While I am sure the information might come back as perfect, no amount of software can "see" a timing belt being shredded.

[TownsendsFJR1300]

With the faulty tensioner, were the bearings worn, making noise and / or was the tensioner NOT running true?

[rodbolt17]

I will repeat myself, at the risk of being cruel.

there ARE NO alignment adjustments to any tensioner,idler drive or driven sprockets.

the ONLY way to check for a damaged/failing thrust bearing is with a dial indicator and a pry bar

do tensioners/idlers fail?
yep I have seen a handful.
typically with several thousand hours.

[TownsendsFJR1300]

I will repeat myself, at the risk of being cruel.

there ARE NO alignment adjustments to any tensioner,idler drive or driven sprockets.

.

If ^^^^ is to my post above, I was asking if the bearings (and there are bearings) wore out in the tensioner. Worn bearings would not put even pressure on the belt..

No place was it mentioned about alignment, alignment adjustments, etc..


IF NOT, dis-regard...

[pstephens46]

Original Poster - Please respond back with the results of your investigation. Very interesting!

[boscoe99]

I will repeat myself, at the risk of being cruel.

there ARE NO alignment adjustments to any tensioner,idler drive or driven sprockets.

the ONLY way to check for a damaged/failing thrust bearing is with a dial indicator and a pry bar

do tensioners/idlers fail?
yep I have seen a handful.
typically with several thousand hours.

It is off to sensitivity training for you.

Remember that we are dealing with millennials at times here and now. They are not used to being corrected.

Everyone gets an attaboy or a participation trophy even if he is moving backwards.