Blown Engine in '99 300M

Looking for opinions here...

Hi folks. Looking for opinions...

I've got a '99 300M that died hard last week. Mechanic hasn't torn it down
yet for a precise diagnosis, but it won't turn over at all, leading us to
suspect that the engine's going to need replacement. I'm pretty sick over
this since it's got less than 70K miles and should have had a lot of life
left in it.

The dealer's telling the mechanic a replacement engine is $6000, which after
the work's done means something on the order of a $9000 repair. This, of
course, gets close to the value of the vehicle itself.

I'm looking for opinions on 1) What a dealer or the company might be willing
and able to do about the cost of the repair; and 2) What alternate parts
sources might exist.

Any thoughts welcome.

Thanks,

DJV

 

It's been my experience that when a car won't turn over most people suspect
a dead battery, DOA computer etc..... is there something else you're
forgetting to tell us? Like maybe you forgot to have the oil changed for
the past 40k miles, or were drag racing when the engine died?

If you were just a normal driver doing routine maintenance, I would call the
Chrysler 800 number and talk to them. They might help cover at least some
of the costs. What have you got to lose?

Good luck;

SRG

 

Not enough info. What does "died hard" mean? Please describe the sequence
of events. Have you owned this car since it was new? What kind of
maintenance do you practice?

Yeah, of course.

www.car-part.com , doesn't look like you should have a tough time finding
a low-miles used engine assembly for $2500 or less.

DS

 

You're right, I should have been more complete. A driver who shall remain
nameless did not know how to use the autostick, pulled it into low, and
drove at 55mph for awhile. After about 10 minutes the engine complained
loudly and smokily. Now the starter motor engages when you turn the key,
but the engine won't rotate.

Oil changes, by the way, were at regular 3000 mile intervals. Thanks for
asking. ;-)

 

I'd look for a low-mileage junkyard engine, as Dan Stern (I believe)
suggested.

And don't let nameless drivers hold the engine at no-load redline for 10
minutes anymore, OK?

 

Whoof. Yeah, that'll do it, especially if "awhile" was actually a *long*
while, and if "55mph" is kind of a guess that might be just a smidge on
the low side.

So the engine didn't *die*, exactly. It was *killed*. I'm not certain why
you're "disappointed"; machines tend to die when they are severely abused.
That's just...what happens!

DS

 

She won't.

 

cheapest engine for 99 300M is $250 located at NE, accourding to
www.car-part.com. it looks like you will get a used one for less than
1000. good luck.

PS: there might be some other sides sellimg much cheaper parts.

 

It's people like you who contribute to Americans' impression that people
who cannot speak English are stupid.

DS

 

I suspect a troll here. The autostick will force an upshift if you redline
the engine. The
3.5 in the 300m will do 6000rpm all day long if it's well maintained.

Just for fun, I tried to force my 99 300m to do what the original poster
claimed.
At about 6500rpm it shifts into 2nd.

That aside, Dan is right. You can't protect a machine from complete idiocy.
If
someone drives a *street* car along for 10 minutes at 6000-7000rpm and then
has the audacity to complain, ummmm.....fook 'em. They're not designed for
that
purpose.

C

 

According to the '99 FSM, the overall drive train ratio in 1st gear is
2.84 (tranny) x 3.66 (final drive) = 10.3944 engine revs/tire rev.

Factory size tires are 83.7" circumference.

Forced 1-2 shift is at 6300 rpm for 3.2L, 6600 rpm for 3.5L.

If you do the math (forced shift speed in mph = 1mi/5280ft x 1 ft/12" x
engine speed at forced shift in rev/min. x 83.7" vehicle travel/1 tire
rev x 60 min./hr. x 1 tire rev/10.3944 engine revs), the shift would be
forced at 50.33 mph for the 3.5L, or 48.04 mph for the 3.2L.

Conclusion #1: 55 mph in 1st gear is not possible - perhaps OP
exaggerated the speed - 50 mph could be done with 3.5L, but not 55 mph.

Draw your own conclusions about whether the engine could survive 6600
rpm indefinitely (questions: What was it's condition? How much oil was
in the sump?)

Conclusion #2: I have too much time on my hands. 8^)

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

 

This doesn't make sense. Autostick will upshift before the engine crosses the
redline.

 

True. It can, however, be held at close to red line at 50 mph (see my
other post). Sustained high engine speed can cause much higher than
normal oil consumption (thru rings, valve seals, or the crankcase vent
system - for example, there's a vent tube *not* connected to the PCV
tube that ports right into the intake tube between the air filter and
the throttle body - oil gets sucked thru that tube at high speed open
throttle situations because the ability of the PCV system is exceeded).
You may have noticed a sudden drop in oil level when checking the level
after a WOT high speed passing situation even in an engine in good shape
- this is not unusual on many engines - and that's just for a few
seconds of abuse.

I can believe that the oil would be steadily depleted at sustained high
speed operation, say at 6000-6500 rpm operation. The oil level could
drop to dangerously low levels within minutes - especially if the oil
level was towards the low side at the start of the episode.

Just a theory - but I think oil starvation is a possible or likely
failure mechanism even for a good engine in this sustained very high
speed operation.

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

 

Bill Putney wrote:

I doubt a stock engine of any make (except maybe a VTEC which is built
fly-weight to start with, and I'll slap the first person that says
"Wankel could handle it for 10 full minutes.

Can I borrow some?

 

I don't think I actually complained, Chris. I did ask solicit ideas from
folks who probably know more about this stuff than I do. If you're one of
them, I thank you for your time.

Best regards,

DJV

 

Yours sounds like as good a theory as I've heard so far, Bill. Thanks for
taking the time.

I too was curious as to why the computer didn't force an upshift. As I
wasn't in the vehicle at the time I can't say with certainty what the speed
or duration was, but the estimates I gave were based on the road traveled
and distance from the origin. It could easily have been running 5-10 mph
below the posted, 55mph speed limit.

The engine had plenty of oil in it to start, but the depletion scenario you
described matches up with the likely conditions at time of death. I'm
learning a lot...tuition's been expensive though.

Again, thanks for your time.

Best regards,

DJV

 

I've never seen this before.

I can't believe this. Airplane engines run at WOT pulling 70-80% of
full power for hour on end. And they are air cooled with looser
tolerances than modern cars by far. They typically burn only a quart
every 5-10 hours. I can't imagine a scenario where an auto engine would
consume oil at the rate of multiple quarts per hour (the rate required
to consume enough in a few minutes to trash the engine). I just don't
believe this is possible.

I agree that oil starvation might be the cause, but not oil exhaustion.
One of the biggest problems with high rpm operation is aeration of the
oil causing the oil pump to "lose prime" and be unable to maintain
sufficient flow and thus pressure. Racing engines typically take steps
to prevent this, things such as windage trays (I think that is the right
terminology) or dry sump oil systems. I'd sooner think this as a likely
cause.

Matt

 

That's, um, nice, MW, but we're not talking about airplane engines here,
and "looser tolerances" have nothing to do with the elements of the PCV
system accurately described in a passage you apparently don't believe.

If that were the mechanism in this case, the engine would probably have
stalled for lack of oil pressure to the hydraulic lifters long before it
seized.

It seized.

DS

 

man you better check around! the motor from a salvage yard is a lot cheaper than
that. u r getting hosed

 

You can also run an airp[lane engine inverted. I doubt you could do
that with a Chrysler LH engine. There are differences in the crankcase
venting, as I pointed out. Believe it or not, oil does get pulled thru
the intake thru a valve cover vent tube when the PCV gets overloaded.

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")