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Author Topic: Failure Analysis: Did a Baldwin PA2721 Filter Failure Kill our 8V71 Engine?  (Read 4089 times)
jdpilot
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« Reply #15 on: October 15, 2013, 08:45:12 AM »

Thanks for the info.. will be going to Napa for a wix filter for my MCI 8v71 before my next trip. Did you post about your engine rebuild anywhere... Price? Who did it?
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technomadia
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« Reply #16 on: October 15, 2013, 10:07:28 AM »

Did you post about your engine rebuild anywhere... Price? Who did it?


We've posted thousands of words and hundreds of pictures:
  http://www.technomadia.com/rebuild

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Cherie and Chris / www.technomadia.com
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« Reply #17 on: October 15, 2013, 10:16:49 AM »

I'd guess too, despite the shredded element, that the air intake wasn't restricted when climbing blow-up hill. Mostly because symptoms of a "gagged" engine were not reported.

Indeed - the engine performed fabulously on the way up. It was not sluggish at all.

I didn't follow along every detail, but I don't recall reading about the "last chance" screen at the blower inlet being littered with filter element. Was it?  If this was a recent and quick element failure, I would think that there would have been "confetti" galore present.

The last chance screen had some paper in it - as did the blower. Not "galore", but I'm not sure how much at all would have stuck around if the filter had failed long previously.

I wonder too if an over-speed -at some time- could have pushed flow up just enough to be able to suck out  the border line element?

I've wondered the same thing - this is the top thought in my mind when I say that we are not sure whether the filter failure caused the engine failure, or was the result of it.

What might have caused an over-speed event? What would the symptoms be?

  - Chris
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TedsBUSted
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« Reply #18 on: October 15, 2013, 03:39:39 PM »

The most likely over-speed  to go unnoticed would be a downhill run that pushed the engine above governed speed.

Another  over-speed scenario could be a "runaway" that's  caused by either excess fuel, or lube-oil ingestion; had that happened it would have been obvious and not gone unnoticed.

My opinion is that from the beginning, for this application, the filter would have been marginal, at best.
Also, I believe that something was lost in the failed filter manufacturer's "translation" of a replacement for the original design and its intended applications.

It happens. Brings to mind  a certain hydraulic filter application in heavy equipment. The OE manufacturer's filters work just fine. However, when "will-fit" substitutes are used, it's almost guaranteed that the element will be found to be  blown-out at the next change, and  sometimes with catastrophic side effects.

Ted

« Last Edit: October 15, 2013, 04:02:01 PM by TedsBUSted » Logged

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« Reply #19 on: October 15, 2013, 05:09:53 PM »

Ted, if they used the direct replacement like a Donaldson P537447 or any other ECO manufactures replacement for the Baldwin PA2721 it's still 1000 cfm and that is close on 8v71 for the 900 cfm for a standard 8v71

 I use 1200 cfm on 8v71 engines with N65 or N70 injectors but we all do it different 
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eagle19952
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« Reply #20 on: October 16, 2013, 10:56:26 AM »

Dang them old  :onasty DD engine killing POS oil bath filters....oh wait, they didn't....
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RJ
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« Reply #21 on: October 16, 2013, 07:39:57 PM »

The most likely over-speed  to go unnoticed would be a downhill run that pushed the engine above governed speed.

Ted -

Don't know if you're aware, but Allisons will automatically shift up to the next higher gear if the engine starts to overspeed.  Even if you've locked it down manually into a lower gear, the transmission will still upshift if it senses overspeeding.

FWIW & HTH. . .

 Wink
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RJ Long
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« Reply #22 on: October 16, 2013, 08:02:32 PM »

How is a 730 in 3rd gear going to up shift if a engine over speeds it has no place to go, they over speed in 3rd being the 4106  has such such low rear gearing  

To me it just got hot and pulled the liner it's the nature of a 8v71 I have 2 in my yard that did the same thing 1 a turbo 8v71 from a 4905 the other a 8v71 N/A from 4106 the filter had nothing to do with it 

They can count their blessing for having  the later 71 with water jackets it could have been a lot heavier on the old pocket book   
« Last Edit: October 16, 2013, 08:29:56 PM by luvrbus » Logged

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« Reply #23 on: October 17, 2013, 06:02:01 AM »

  A day of driving in the rain is going to get the air filter damp and wet. Maybe not that day, but some time earlier.Minimal excess filter capacity, a little dust and dirt in the pleats, filter distortion, then deterioration and collapse, not noticing exhaust getting darker and temp climbing for how many minutes?Huh It happens....these things make owners start to be more aware of their vehicle's operating conditions, almost to paranoia. I'll bet that you monitor conditions more closely now. Same when brakes get out of adjustment and barely slow down vehicle on grade, or tire blows due to low air or worn out, etc,etc. I.d at least make sure that the filters from now on have metal supporting mesh, and plenty of reserve capacity, and move on. Don't lug it, don't let it overheat, don't let the oil get get low to empty, don't let coolant get low, and don't over rev it, and it should run a long, long time.
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« Reply #24 on: October 17, 2013, 08:40:34 AM »

We found a broken liner was due to being too snug in the block bore, and not dropping in and / or driving in with force / hammer. A proper fit have not seen one break.
Dave M
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« Reply #25 on: October 17, 2013, 09:14:17 AM »

That causes it too Dave I saw that more than once where people did not know you can by liners in std or oversize size or the 1,2,3 in sizes they buy a std and drop in or force in it makes no difference as it takes to long for a person to hone a cylinder for a perfect fit loose can be as bad as tight, it doesn't me being retired all I have is time or what left of anyway lol
« Last Edit: October 17, 2013, 09:22:05 AM by luvrbus » Logged

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« Reply #26 on: October 17, 2013, 05:16:18 PM »

luvrbus,
Gee, that is a fact, along with the correct depth of liner so the compressin ring seals correctly, there are many areas where a guy can really screw up, but when they are right, they are RIGHT.  All that is one reason I love the two strokers, once you get real comfy with them, evey thing else has no appeal.  But being over the hill, I now have to pay for what ever is done, not able to crawl around and under like 25 yrs ago.  Am lucky to have a good employee who is great at following directions and learning.  Getting old is not so bad, you just have to laugh at lots of fools & foolishness.
Life is great as long as the ISM500 keeps puttin out. The ISM is no class like the 12V-71, that is class.  Grin
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RJ
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« Reply #27 on: October 17, 2013, 07:02:43 PM »

How is a 730 in 3rd gear going to up shift if a engine over speeds it has no place to go, they over speed in 3rd being the 4106  has such such low rear gearing.

Clifford -

Sorry, I disagree.

A stock 4106 with a V-730 will have a overall final drive ratio of 3.588:1 in 3rd (high) gear. 

That's "taller" than the stock 3.70:1 in an MCI, and lots of others. 

With 500 rev/mile tires, that means they'd have to be doing well over 75 mph to overspeed the 8V.  (75 mph is 2250 with this tire/rear axle ratio combo.)

FWIW & HTH. . .

 Wink



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RJ Long
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« Reply #28 on: October 17, 2013, 07:51:53 PM »

RJ what are we calling stock I am just trying to figure it out using the 3rd gear ratio of a 730 at 0.875 to 1 and a TC 470 torque converter

 good luck
« Last Edit: October 17, 2013, 08:03:17 PM by luvrbus » Logged

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« Reply #29 on: October 18, 2013, 10:54:00 AM »

RJ, what are we calling stock? I am just trying to figure it out using the 3rd gear ratio of a 730 at 0.875 to 1 and a TC 470 torque converter

Clifford -

3rd gear in a V-730 has a ratio of 1:1.  Not sure why you've included the torque converter, once it's locked up it's not part of the equation.

The bevel gear set is 0.875:1 in this transmission.  It's 0.808:1 in the 4-spd manual.

The OEM stock rear axle ratio is 4.125:1.

The overall rear axle ratio is the product of the following math: (High gear ratio) x (bevel gear ratio) x (rear axle ratio) = overall rear axle ratio.

Plugging in the numbers gives you:

(1:1) x (0.875:1) x (4.125:1) =

(1) x (0.875) x (4.125) = 3.609375, or simply 3.61:1

(In the post above yours, I rounded off the bevel gear ratio to 0.87:1, hence the slight difference of 3.588 vs 3.609.)

Either way, it's still a "taller" ratio than the others.

Running the numbers for the manual gearbox and you get an overall ratio of 3.333:1, which, with 500 rpm tires, sends the 4106 down the highway a little over 80 mph @ 2250 rpm.  Since it's been said often here and on other Detroit-related websites that 8Vs have be set to 2400 rpm in certain applications, certainly 2250 is not "overspeeding" the engine.  Not recommended, obviously. . .

If you really want to go slightly crazy, then we could include installing V-730s in 4905s!   Grin

FWIW & HTH. . .

 Wink
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RJ Long
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