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  • SN95 4.6L Mustang Tech

Unexplained ENGINE FAILURE in the '01 Cobra

  • Thread starter Thread starter HoustonGT
  • Start date Start date Dec 2, 2008

HoustonGT

Gilded Gelding
Apr 6, 2003
1,418
0
0
Houston
Dec 2, 2008
#1
  • Dec 2, 2008
  • #1
Well, I hope Thanksgiving was good fo all of you because let's just say mine consisted of oil and metal....
I let my very close friend borrow the Cobra in the morning to make a quick trip to his house and back before everyone gathered for the Thanksgiving feast. Caught a ride with my sister to my aunt's house and told him to met us there and about 5 minutes out he calls me and asks if its normal for my car to smoke occassionally and smell like oil....NO ITS NOT . Well he tries to baby it the rest of the way and as he pulls up in front of her house i see faint smoke from under the hood of the car and coming out of the driver's side fender , so he immediately shuts the car off and pops the hood.

As I open the hood, the first thing i notice is the pool of oil under the car and the trail of it on the road of where he made the turn. Then as i panic i notice something worse....The driver's side valve cover is cracked COMPLETELY in half right above the driver's side cam gear. My heart sinks and i dont know whats wrong, but later we notice that the bolt that holds the cam gear in place is missing and notice scarring on the valve cover peice that broke off and on some parts of the timing over. There are little peices that look like copper shavings down by the chain and in a few other spots but i dont know if thats parts of the bolt. My guess is after it broke off the chain caught it, and shot it up against the valve cover breaking it clean in half.
Does anyone know what would cause the bolt to shear off in half like that? I see no real other damage and plan to pull the timing cover and remaining valve cover off tomorrow.
Could i be lucky enough to where it bolt hit and then fell to the bottom and is simply laying in the oil pan? As of right now the bolt has to be replaced and so does the valve cover, but the extent of the damage is unknown for that.
I plan on contacting Ford and Svt to let them know of the situation since this car has never been taken apart and a damn bolt should not break in half especially in a hand-assembled motor in hopes that they can do something about it.

Here are some pre-leminary pictures:
 

BigHairyMonkey

Founding Member
Jun 18, 2003
411
1
16
Houston (Bellaire) TX
Dec 2, 2008
#2
  • Dec 2, 2008
  • #2
man id woop that friends ass if i was you..... yea the car started smokin as i drove on the freeway around 80mph prob like 2500rpm. i slowed down thinking someone else in front of me was burning oil.. but alas, it was mikes car. From the beginning to end the car was probably driven a good 2 miles after the damage happened.

the only reason i drove the car and didnt just shut it off was because this has happened before when the tranny oil was spilling out on to the headers and smokin just like that; i thought this was the same issue. here are some pics we snapped with the phone.




 

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hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Dec 2, 2008
#3
  • Dec 2, 2008
  • #3
WOW I have never seen anything like that!!!!!!!!!! Sorry to hear that Did you rev it out any before hand? In any case it shouldnt have done that...however it looks to me like you have skipped disaster since you didnt mention any piston to valve contact noises.

Since it was still pouring out oil, also looks like you didnt run the bearings dry either.

Replace the bolt, valve cover, oil filter, oil....fire the engine up and run it for a few minutes. then test compression and do a leak down test if you can....if all checks out, replace oil again and you should be ok. Most metal should go straight to the bottom of the pan...and since you were only doing 2500RPMs....that helps alot in not sucking up shavings.

May be a good time to throw in some FR500 cams

Good luck bro! Let me know if you have any questions!

BTW MAKE SURE IT DIDNT JUMP TIMING...VERIFY THE CAM GEAR IS STILL IN THE KEY WAY! (caps FTW) and be sure to wash all those shavings down to teh bottom of the pan...take your time there.
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
4
39
UCSD/La Jolla
Dec 2, 2008
#4
  • Dec 2, 2008
  • #4
Use a expendable magnetic tool and probe around in the pan while the cover is off. Might find a bolt, although it wont pick up aluminum timing cover bits.
 

mustang50v8

Member
Feb 4, 2003
548
3
18
847 Chicago Burbs
Dec 3, 2008
#5
  • Dec 3, 2008
  • #5
that sucks dude i know exactly how it feels. how many miles were on the car?

my oil pump blew up in my car which caused no oil pressure to the rest of the motor.




the heads ran dry and one of the driver side cams seized on the cap. if the caps on the heads are ruined so are the heads as a result of the way they are manufactured. they are made as one on the assembly line and you cant mix and match caps from different heads, even from passenger side to driver side on the same motor.


the chain snapped and was spinning around but didnt cause any damage like that to my valve cover but there were metal shavings all over the place. when the oil was drained it looked like glitter.


i dont want to scare you but be prepared for the worst. it may have just been the cam bolt that backed itself out or something more serious in the bottom failed causing a chain reaction of events (like in my case). if it is the worst case scenario, if your engine is stock, you may want to look into buying a replacement longblock.


here is a link to my engine build from a couple weeks ago
 

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tag4car

Member
Nov 21, 2005
0
0
16
Birmingham AL
Dec 3, 2008
#6
  • Dec 3, 2008
  • #6
similar problem here on this thread. hmm

http://forums.stangnet.com/768016-cam-seized-timing-chain-broke-10k-miles.html
 

the98stang

Active Member
Aug 12, 2005
2,408
0
47
Clovis, CA
Dec 3, 2008
#7
  • Dec 3, 2008
  • #7
HoustonGT said:
Well, I hope Thanksgiving was good fo all of you because let's just say mine consisted of oil and metal....
I let my very close friend borrow the Cobra in the morning to make a quick trip to his house and back before everyone gathered for the Thanksgiving feast. Caught a ride with my sister to my aunt's house and told him to met us there and about 5 minutes out he calls me and asks if its normal for my car to smoke occassionally and smell like oil....NO ITS NOT . Well he tries to baby it the rest of the way and as he pulls up in front of her house i see faint smoke from under the hood of the car and coming out of the driver's side fender , so he immediately shuts the car off and pops the hood.

As I open the hood, the first thing i notice is the pool of oil under the car and the trail of it on the road of where he made the turn. Then as i panic i notice something worse....The driver's side valve cover is cracked COMPLETELY in half right above the driver's side cam gear. My heart sinks and i dont know whats wrong, but later we notice that the bolt that holds the cam gear in place is missing and notice scarring on the valve cover peice that broke off and on some parts of the timing over. There are little peices that look like copper shavings down by the chain and in a few other spots but i dont know if thats parts of the bolt. My guess is after it broke off the chain caught it, and shot it up against the valve cover breaking it clean in half.
Does anyone know what would cause the bolt to shear off in half like that? I see no real other damage and plan to pull the timing cover and remaining valve cover off tomorrow.
Could i be lucky enough to where it bolt hit and then fell to the bottom and is simply laying in the oil pan? As of right now the bolt has to be replaced and so does the valve cover, but the extent of the damage is unknown for that.
I plan on contacting Ford and Svt to let them know of the situation since this car has never been taken apart and a damn bolt should not break in half especially in a hand-assembled motor in hopes that they can do something about it.

Here are some pre-leminary pictures:
Click to expand...

Compression test and leak down are needed for sure. Hope everything is alright...

This is why NO ONE drives my car but me....
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 3, 2008
#8
  • Dec 3, 2008
  • #8
I cant see pic but my story was all summer .broken cam gear and follower feel of. Was cyl 6 the one? I had to pull engine to remove all metal.oil screen was clogged and oil cooler was cleaned but ford suggest replacement if any metal is present. After both sides broke i have pistons with valve marks but 10k since rebuild .good luck its gonna cost you a couple of thousand to fix .mine done myself 2grand and that was only head gaskets with boltr 500. Head repair 900 and electric fan 200. 3 cam gears and 2 adjusters 300. Supplys 200. Good luck
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
24
58
Dec 3, 2008
#9
  • Dec 3, 2008
  • #9
Damn man, that sucks.

If it was still running, thats a good sign... but ALWAYS stop and see what the hell is going on if the car starts smoking!!! You MAY have gotten VERY lucky as the hole is in the top of the engine, and not the bottom so you probaly didn't empty all of the oil... however, you really need to pull the oil pan and get any metal shavings out of it, as well as the oil pump pickup screen AND see if there is any plastic laying in there.

PLEASE don't start the car back up and assume that just because nothing REALLY messed the motor up on the trip home, that it can't happen now. There may be a bolt sitting in the pan that is just waiting to get smacked by a rotating crank and thrown up into a piston.
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
28
119
Motor City
Dec 3, 2008
#10
  • Dec 3, 2008
  • #10
That's why I never let people drive my car, nor do I want to drive anybody elses.
 

HoustonGT

Gilded Gelding
Apr 6, 2003
1,418
0
0
Houston
Dec 4, 2008
#11
  • Dec 4, 2008
  • #11
Drain the oil from the car and have some good news.
First, there were no metal shavings to be found and the oil looked very clean. And also, the pan had a good 3-4 quarts still left in it meaning the motor did not get close to running dry.
I went ahead and unbolted all 16 bolts holding the oil pan on, but realized id have to loosen and move the rack to get the pan out. It got dark, so i'll leave that for tomorrow and if i find there is no bolt or metal, im gonna consider myself one lucky SOB.

That'll mean all that will be left is to replace the valve cover, check the chains for damage and any metal shards, replace the cam gear bolt, and replace the timing cover. Then fire her up and pray for a miracle.
 
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