View Full Version : Engine Autopsy... **DUW**
2ndMDRebel
03-19-2008, 05:13 PM
First came the task of getting the engine out of the car and after a few failed attempts it finally came out. Got the engine on a stand and took off the oil pan. When the oil was drained it was clean and we didn't see any debris, it was just changed two weeks prior to the failure, same as always, 5-20 Motorcraft full synthetic, every 90 days. So, inside the oil pan was a slurry of aluminum lining the bottom. We then took off the pickup tube, the screen was clean and clear, and the small tray. The con-rod caps were next and that told the story. Every last one was spun and obviously oil starved. Also it was easy to see the discoloration of the main bearings without having to remove the mains.
Initial thoughts are one, the oil pump died, two, the oil all got sucked up into the heads and caused the oil starvation, or three, this was the cumulative effect of wear over time that finally killed it because of all the aluminum in the pan.
Tomorrow we should have the heads off and fully check the pistons and cams/etc and can then get a better picture of what caused it and what the extent of the damage is.
Now the pictures...
Tried to drop the engine/trans together out the bottom, one problem with that is the DOHC doesn't fit between the frame rails, whole subframe was out...
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture160.jpg
Woohoo! the engine is out!
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture162.jpg
Looky what's in the pan! No, I'm not flipping it off...
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture165.jpg
What the... is it sticking its tongue out at me?????
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture168.jpg
Got Oil?
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture174_691356.jpg
Ummmm no!
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture169.jpg
More pics and evaluation soon!
Kennyrauder
03-19-2008, 05:33 PM
Sure looks like oil starvation OR could it be that the 5W20 just can't take the heat & load resulting in lubrication shear. I have ran 5W30 full synthetic since new with the blessing of our factory techs. Good luck I hope you are not going to try & do a rebuild.... find a crate motor with a little more punch & better internals.
I sure would like to see the oil pump. Bearing material flaking off due to fatigue failure of bearing surface from high loads and high temperature. When missing material reaches edge of the bearing, oil pressure (formed by the pumping action of the journal in the bearing bore) no longer forms between the bearing and the journal. Since oil is the medium used to separate the rotating shaft from the bearing, without oil pressure (which can be as high as 6,000-8000 psi), the journal rotating on the dry bearing melts and destroys the bearing. Increased clearance caused by the melted bearing material results in the rod bolts pounding and eventually failing. Fatigue starts at the load zone which is usually in the center. Tri-metal bearings (steel-copper-tin/lead alloy) or older "silver" bearings have several properties that enhance their fatigue strength over aluminum-tin bearings.
John Nero
03-19-2008, 06:17 PM
i think a real oil pressure gauge would tell alot of what is going on inside an engine(oil pump and screen)
sailsmen
03-19-2008, 09:32 PM
As above look at the oil pump. Pre-ignition can reverb thru the crank and turn the Powder Metal Oil Pump Gear back to powder.
Have you made a decision on a replacement?
Dude,
Sorry for your loss! That slurry is the telltale. That much AL didn't come from the bearings or the crankshaft journals. It's also too much to be from the cam journals which I think are AL on the MM engine. That much crud is from the oil pump, I'd almost bet. Next task is to figure out what initiated the self-destruction/disintegration!
Best luck,
J
Marauderjack
03-20-2008, 04:39 AM
I'm with Billy.....oil pump fell apart!!:argue:
Since the only way oil can get to the cam area is through restricted oil ways there really is no way ALL the oil can end up in the cam covers....the return drains and pressure bypass valve ensure the oil supply in the pan!!:beer:
Now, if for some reason the oil level was a couple quarts low you could possibly suck air and eventually do the damage you see here but it would take awhile of constant abuse.....and you would probably hear or detect something in the process!!:eek: If the oil pump is OK I'd suspect this scenario!!:shake:
All the aluminum in the pan is probably bearing material??:confused:
Are you going to check the oil pump??:confused:
I wonder how hard it is to swap the oil pump impeller with the engine in the car....can it be done??:cool: If so I may consider doing it!!:rolleyes:
Marauderjack:bandit:
Definitely the oil pump.
Good thing it didnt ventilate the block!
RE-USE it!
I meant reuse the block only for a rebuild, not the block and rotating assembly!
vkirkend
03-20-2008, 05:47 AM
You and your engine have my condolences....
ckadiddle
03-20-2008, 06:35 AM
You and your engine have my condolences....
Same from me. I do appreciate it when you guys go to the trouble to photograph and diagnose these things. A lot of it goes right over my head, but I do learn stuff. Thanks!
2ndMDRebel
03-20-2008, 10:53 AM
Still doing the teardown in between customer cars. The oil pump is gone, wiped out, toast. I took Some more pictures but the camera battery is dead, will post what I have later after work. The heads are off and he will have the crank and pistons out this afternoon.
Quick question... is the oil pump in the 03/04 Cobra DOHC engine the same as this one?
sailsmen
03-20-2008, 11:27 AM
My memory, which may not be 100% accurate, is that when some of the Entech's were bumped up in HP the Oil Pump Gears failed.
Many blamed it on the fact they were powdered metal and replaced with machined oil pump gears.
Then it was learned that the Oil Pump Gears were failing due to pre-ignition.
I have heard less talk about the necessity for machined oil pump gears.
It is my understanding the Cobra has the same oil pump gears as the Marauder.
Could you have had a lean condition due to fuel delivery, less octane due to alky delivery or more heat due to IC pump failure?
I don't know if you were able to extract any data from the PCM.
Dennis Reinhart
03-20-2008, 11:28 AM
Pull the oil pump off and take it apart I would bet the gears are broken.
ctrlraven
03-20-2008, 11:40 AM
That sucks Tom, hope you get her back up and running soon without too much trouble.
Buy a Melling pump to put back in
Buy a Melling pump to put back in
I would purchase the Melling pump, but I would not spend the time or money to put that short block by in. :flamer: You have a ton of other options.
2ndMDRebel
03-20-2008, 12:33 PM
Its possible I can get a 03/04 Cobra DOHC longblock for $100 over dealership cost. This is less than the "1100HP" shortblock I was looking at from MMR and about $5500 less than their longblock. My tech said the heads look ok but I'm a little squeamish about reusing the heads since the oil issue was the cause of failure. The oil pump is crumbled, I haven't opened it up but you can see the mess inside it. A Cobra longblock with a better oil pump is looking real good right now, just have to weigh the options a bit.
It sounds like you are working on a good plan.
Its possible I can get a 03/04 Cobra DOHC longblock for $100 over dealership cost. This is less than the "1100HP" shortblock I was looking at from MMR and about $5500 less than their longblock. My tech said the heads look ok but I'm a little squeamish about reusing the heads since the oil issue was the cause of failure. The oil pump is crumbled, I haven't opened it up but you can see the mess inside it. A Cobra longblock with a better oil pump is looking real good right now, just have to weigh the options a bit.
Stick with high compression, especially with a Vortech
Again, my shortblock is still available!
2ndMDRebel
03-20-2008, 04:18 PM
It was definitely the oil pump, where the crank goes through is cracked in a couple spots and actually has a gap...
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture181.jpg
ewwww!
The engine is about 90% tore down now. I don't know whether to send the heads to the machine shop or just write them off.
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture180.jpg
The Cobra longblock is not an option now, called parts hotline and they confirmed the block can be in any condition but it must be the same part, the aluminum block will not satisfy the core requirement and the core charge of $2k would be applied. At $5,660 + 6% tax it doesn't seem worth it.
CRUZTAKER
03-20-2008, 05:47 PM
Wow...another person going down that road I walked last year. :welcome:
My oil pump decided to grenade one afternoon without any leading failure.
My Motor looked like new internally when Zack tore it down.
I believe he used a Melling replacement on mine as well.
Info: http://www.mercurymarauder.net/forums/vbgarage.php?do=view&id=626
We decided a cobra iron block would be my best bet for the long term roughage I was going to give it. I am very pleased with with it's endurance thus far. Still spraying it! It should enjoy the Vortec we're installing this spring as well.
I don't how far you are from Zack but I'd buy the motor he has on hand. ;)
Doh! That's right....I DID ONCE ALREADY! :banana2:
He also required I put the real oil pressure guage in this time.
http://www.mercurymarauder.net/showcase/files/6/2/6/DSC02641.jpg
http://www.mercurymarauder.net/showcase/files/6/2/6/DSC02643.jpg
http://www.mercurymarauder.net/showcase/files/6/2/6/DSC02655.jpg
http://www.mercurymarauder.net/showcase/files/6/2/6/DSC02652.jpg
http://www.mercurymarauder.net/showcase/files/6/2/6/DSC02653.jpg
http://www.mercurymarauder.net/showcase/files/6/2/6/DSC02654.jpg
Marauderjack
03-21-2008, 04:06 AM
I ask again......
Can the oil pump be replaced with the engine in the car???:rolleyes:
Bluerauder
03-21-2008, 04:32 AM
Thanks to Tom, Mark, Chris, Zack and everyone on this board who has the knowledge and skills to tackle a job like this and post up the information and pics for the less mechanically inclined among us. :2thumbs: I continue to learn more and more everyday on this site. Thanks guys. :D
sailsmen
03-21-2008, 07:13 AM
It's important to find out what caused the Oil Pump to break.
Strengthen one link and the next link will break.
Something happened to cause it to break.
I ask again......
Can the oil pump be replaced with the engine in the car???:rolleyes:
Yes, although lining it back up with the pick up tube would be a real pain.
It's important to find out what caused the Oil Pump to break.
Strengthen one link and the next link will break.
Something happened to cause it to break.
I was thinking the same thing. I would love to see pictures of the front and real seal.
The car detonated, end of story.
The car detonated, end of story.
...I want to add to this if I may.
VERY IMPORTANT!
If you drive to the track with a near empty fuel tank, and fill up with race gas at the track, you need to know this:
Your car needs do either run for 5 minutes, or drive the car around the pits for the equivalent of a few blocks.
It takes that long for all of the 93 octane to be used up out of the fuel lines and fuel rails.
PLEASE remember this!
Put the race tune in and mash it with 93 octane still in the lines and you will most likely nuke the oil pump during your burnout.
The engine will be trashed down the 1320. Bad situation!
magindat
03-21-2008, 09:59 AM
...I want to add to this if I may.
VERY IMPORTANT!
If you drive to the track with a near empty fuel tank, and fill up with race gas at the track, you need to know this:
Your car needs do either run for 5 minutes, or drive the car around the pits for the equivalent of a few blocks.
It takes that long for all of the 93 octane to be used up out of the fuel lines and fuel rails.
PLEASE remember this!
Put the race tune in and mash it with 93 octane still in the lines and you will most likely nuke the oil pump during your burnout.
The engine will be trashed down the 1320. Bad situation!
I assume this info is for those using race gas tunes at the track...?
I assume this info is for those using race gas tunes at the track...?
Absolutely, thanks for bringing that up :up:
2ndMDRebel
03-21-2008, 11:05 AM
...I want to add to this if I may.
VERY IMPORTANT!
If you drive to the track with a near empty fuel tank, and fill up with race gas at the track, you need to know this:
Your car needs do either run for 5 minutes, or drive the car around the pits for the equivalent of a few blocks.
It takes that long for all of the 93 octane to be used up out of the fuel lines and fuel rails.
PLEASE remember this!
Put the race tune in and mash it with 93 octane still in the lines and you will most likely nuke the oil pump during your burnout.
The engine will be trashed down the 1320. Bad situation!
Just FYI, I prepped the car the day before, that meant drag radials were on, flluids checked, "race tune" plugged in, had the fuel gage sitting just below E (2 gallons in tank) and added 5 gallons of 110 octane CAM2 from the station just up the street. I take it very easy until I get to the track, thats a 15ish mile drive to get the 93 out of the system, I always thought there was about a quart or so of fuel between the tank and the engine.
On the run the only thing I noticed different was how damn hard the car was pulling, actually had a tight grip on the wheel and was thinking "holy crap" as it was going down the track. I wasn't into my usual routine of watching the various gauges and timeboard because it caught me by surprise and I was rusty.
I don't know what caused it to go, at first I though bad gas if the CAM2 stuff was sitting all winter in the ground but wouldn't that make the car run poorly? Then I thought maybe the methanol didn't spray but the reservoir was down like it normally goes during a run. I didn't hear the classic "marbles in a tin can" detonation, heck, with the longtubes, rollbar, helmet, and adrenalin pumping there's not too much I think I could have heard. One thing I did do was replace the tensioner and belt a couple weeks before the race. maybe it was getting full boost and the 40 degree air was just too much? Lidio's street tune (93 pump gas) was with a 10.5 a/f ratio and that got me the 504rwhp, for the race tune he added 5 degrees of timing across the board.
Back to the engine, I can look at the crank seals, just let me know what I should be looking for. My tech showed me that the crank is bent slightly, not sure what that means overall with regards to the failure. The block is now completely stripped and the heads are over at our machine shop to be checked and cleaned.
sailsmen
03-21-2008, 11:20 AM
If the fuel and fuel supply is good.
Check the Inter Cooler pump and reservoir.
Back to the engine, I can look at the crank seals, just let me know what I should be looking for. My tech showed me that the crank is bent slightly, not sure what that means overall with regards to the failure. The block is now completely stripped and the heads are over at our machine shop to be checked and cleaned.
The stock crank I think is rated at or around the 500 rwhp mark and failure could occur between 500-600 range. Bearing and seals could be damaged from wobble. You may have hit the limits of you stock motor. The oil pump failure was the weak link. I suspect the problem didn't start with your pump, but it certainly ended their.
Read this tread.
http://forums.stangnet.com/showthread.php?t=676669
Take a look at this one also
http://www.corral.net/forums/showthread.php?t=930470%5C
For all you Mobil 1 guys
http://www.modularfords.com/forums/showthread.php?t=38620
MarauderTJA
03-22-2008, 06:08 AM
Its possible I can get a 03/04 Cobra DOHC longblock for $100 over dealership cost. This is less than the "1100HP" shortblock I was looking at from MMR and about $5500 less than their longblock. My tech said the heads look ok but I'm a little squeamish about reusing the heads since the oil issue was the cause of failure. The oil pump is crumbled, I haven't opened it up but you can see the mess inside it. A Cobra longblock with a better oil pump is looking real good right now, just have to weigh the options a bit.
I would use your stock block (if it is OK) bore it 20 over, FMS bearings, get a Cobra forged crank, some Manley rods, CP Pistons (get the assembley balanced), new oil pump and a new 05 Mustang GT water pump. A nice set of Patriot heads and you are good to go.
I would use your stock block (if it is OK) bore it 20 over, FMS bearings, get a Cobra forged crank, some Manley rods, CP Pistons (get the assembley balanced), new oil pump and a new 05 Mustang GT water pump. A nice set of Patriot heads and you are good to go.
Patriot Heads Tom?
They have just as many complaints as compliments :confused:
They are more suited to doing LSx heads anyway
2ndMDRebel
03-22-2008, 06:27 AM
The stock crank I think is rated at or around the 500 rwhp mark and failure could occur between 500-600 range. Bearing and seals could be damaged from wobble. You may have hit the limits of you stock motor. The oil pump failure was the weak link. I suspect the problem didn't start with your pump, but it certainly end their.
Read this tread.
http://forums.stangnet.com/showthread.php?t=676669
Take a look at this one also
http://www.corral.net/forums/showthread.php?t=930470%5C
For all you Mobil 1 guys
http://www.modularfords.com/forums/showthread.php?t=38620
I wonder if my crank bent under load then killed the pump or if the crank bending was a result of the engine seizing? That was some good reading, thanks for the links. The engine has only seen Motorcraft oil filters and full synthetic 5-20 Motorcraft oil since the first oil change. I have to clear out the shop today and will be putting the parts in my storage lot, the car is sitting in the tow-in lane.
Charlie, owner of the machine shop, said he should have the heads looked over by Tuesday. Keeping my fingers crossed that they are ok.
I knew this day was coming but wasn't quite expecting it so soon. Just wanted to thank everyone for their help and caring, from the insightful replies to the PMs of support. Even though its just a Crown Vic that doesn't seem to matter, thank you all.
Mike Poore
03-22-2008, 06:28 AM
Tom, give Joe Walsh a shout. He built a bulletproof 5.0 along with all the proper pumps, reservoirs, and attendant good stuff to go along with it.
Now that you're at this juncture, why do it any other way?
JACook
03-24-2008, 07:41 PM
I didn't hear the classic "marbles in a tin can" detonation, heck, with the longtubes, rollbar, helmet, and adrenalin pumping there's not too much I think I could have heard.
Just another $0.02-
Detonation is often not audible at all. I've run a few engines into detonation, where the
only 'sound' was more of a dull thudding, not the the 'marbles in a tin can' pinging. The
wear stripes on the rod bearings, (and in one case, a fractured main cap) confirmed my
suspicions. You broke the pump, you were detonating. Only question is why.
Marauderjack
03-25-2008, 04:28 AM
Just FYI, I prepped the car the day before, that meant drag radials were on, flluids checked, "race tune" plugged in, had the fuel gage sitting just below E (2 gallons in tank) and added 5 gallons of 110 octane CAM2 from the station just up the street. I take it very easy until I get to the track, thats a 15ish mile drive to get the 93 out of the system, I always thought there was about a quart or so of fuel between the tank and the engine.
On the run the only thing I noticed different was how damn hard the car was pulling, actually had a tight grip on the wheel and was thinking "holy crap" as it was going down the track. I wasn't into my usual routine of watching the various gauges and timeboard because it caught me by surprise and I was rusty.
I don't know what caused it to go, at first I though bad gas if the CAM2 stuff was sitting all winter in the ground but wouldn't that make the car run poorly? Then I thought maybe the methanol didn't spray but the reservoir was down like it normally goes during a run. I didn't hear the classic "marbles in a tin can" detonation, heck, with the longtubes, rollbar, helmet, and adrenalin pumping there's not too much I think I could have heard. One thing I did do was replace the tensioner and belt a couple weeks before the race. maybe it was getting full boost and the 40 degree air was just too much? Lidio's street tune (93 pump gas) was with a 10.5 a/f ratio and that got me the 504rwhp, for the race tune he added 5 degrees of timing across the board.
Back to the engine, I can look at the crank seals, just let me know what I should be looking for. My tech showed me that the crank is bent slightly, not sure what that means overall with regards to the failure. The block is now completely stripped and the heads are over at our machine shop to be checked and cleaned.
I have often wondered how folks make the transition from 93 octane to 110 octane for "Race Gas" tunes??:cool:
If you really had only 2 gallons 0f 93 octane in the tank when on "E" and added 5 gallons of 110 octane the mixture would only be around 105 octane at best??!!:eek: If you actually had 3-4 gallons of 93 octane the resultant mixture will barely be 100 octane......BAD NEWS!!:shake:
Personally I think brewing your own fuels for "Cutting Edge" race tunes is extremely risky and this is probably what took your engine out??:confused:
You had mentioned the car was pulling really hard which leads me to believe you had way too much spark advance for the octane of your fuel mixture!!:help:
Good Luck with your rebuild!!:beer:
Marauderjack:burnout:
2ndMDRebel
03-26-2008, 08:27 PM
They called over from the machine shop today and it looks like the heads are good to go. While they are there I'm having them stripped and cleaned and freshened up a bit and should have them back early next week.
I guess this brings the thread to an end. Autopsy is complete but still I don't know what caused the pump to fail or, if it was detonation, what exactly caused the detonation. Several possibilities exist and I will definitely be taking precautions on the rebuild and subsequent retuning. I hope the information we all shared can help someone avoid the same fate.
Coming soon, the rebuild project thread! (otherwise known as the "Tom has no clue what works so will ask a million stupid questions" thread)
We can make it stronger, faster, better than it was before... (cue 6-million dollar man theme) :burnout:
Its all good, at least my dog still loves me.
http://www.mercurymarauder.net/showcase/files/4/0/8/0/Picture156.jpg
sailsmen
03-26-2008, 08:33 PM
Thanks for sharing the info.
IMHO ~450RWHP is the max safe on a stock motor.
500RWHP leaves no margin.
A number of Marauder engines have gone at 500RWHP. A lot have stayed together for a long time at 450RWHP.
I am only sharing this in the event you go back w/ a stock short block thing long before going over 450RWHP.
Vortech347
03-27-2008, 12:20 PM
Daaaaaaaaaaaaaaymn
You'll have it back together in no-time.
Vortech347
03-27-2008, 12:21 PM
There is a reason ford didn't use these rods/pistons in the 03/04 cobra's.
CRAPOLA!
fairlane347
04-10-2008, 06:14 AM
WOW that's way worse than my engine. I just got mine out too. Spun a bearing too. I feal your pain.
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