A bad day...
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Instructor
Joined: Apr 2005
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From: Göteborg
A bad day...
I finally decided to take the car to the dyno to find out why it does not perform. Found a Dynojet about 45 minutes drive from home and started the drive this morning. Came only 20 minutes from home when the car started to act up; a strange "mechanical" sound from the engine. Took the serpentine belt off but the sound did not go away so its something inside the engine
Had to flat bed the car home.
When I arrived home my other car had a flat tire....
Had to flat bed the car home.
When I arrived home my other car had a flat tire....
Last edited by bogor; Sep 8, 2014 at 09:05 AM.
Thread Starter
Instructor
Joined: Apr 2005
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From: Göteborg
I have removed the driver side valvecover and no visible damage. Only thing I noticed was one of the rocker arms for cylinder one was quite loose. Dont know if this can cause the sounds as can be heard on the video and the funny thing it just came out of the blue today. Maybe a bad lifter.
Drifting
Joined: Feb 2013
Posts: 1,465
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I have removed the driver side valvecover and no visible damage. Only thing I noticed was one of the rocker arms for cylinder one was quite loose. Dont know if this can cause the sounds as can be heard on the video and the funny thing it just came out of the blue today. Maybe a bad lifter.
Instructor
Joined: Sep 2014
Posts: 169
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PLEASE DONT START THAT THING AGAIN!!! You can go from a $100 fix to a $2000 fix even at idle! That looks like to nice of a set up to ruin. Trust me I have done it. Not tryng to be an *** do as you please but don't start that thing again til u find the problem. I suggest its in the valve train. Im going to go against the grain and say valve spring broke or a rocker as stated before. Keep us updated
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Thread Starter
Instructor
Joined: Apr 2005
Posts: 228
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From: Göteborg
Well, too late.... I removed both valve covers and everything looked ok. I adjusted the valves to 0.5 turn after zero lash but no change. Im in the process of doing a leakdown test and I have now checked driver side cylinders (1,3,5&7) and the result indicate the pistons are ok (result was between 89 and 94% on a cold engine).
I have started to tear down the engine so hopefully I know more soon.
I have started to tear down the engine so hopefully I know more soon.
Racer
Joined: Jul 2004
Posts: 315
Likes: 15
From: Ornskoldsvik
Well, too late.... I removed both valve covers and everything looked ok. I adjusted the valves to 0.5 turn after zero lash but no change. Im in the process of doing a leakdown test and I have now checked driver side cylinders (1,3,5&7) and the result indicate the pistons are ok (result was between 89 and 94% on a cold engine).
I have started to tear down the engine so hopefully I know more soon.
I have started to tear down the engine so hopefully I know more soon.
Any detonation when it happened?
/Svante
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From: Göteborg
I recall slightly more pronounced when I increased rpm (only tested at standstill with zero load) but I have not really run it Since it happened and now the engine is getting close to be out of the car.
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From: Göteborg
I've found the culprit now: no3 rod bearing is shot. I have not removed the pan so I cannot yet establish how bad it is but its possible to whiggle the piston up and down in the bore (I have removed the head). Lets hope the rod is still intact and its only the bearing. Could not see any metal in the oil but there's some on the magnetic oil pan plug. I also have a fairly strong magnet on the oil filter so hopefully all ferrous stuff has been trapped. Will see when I open up the oil filter. To be continued...
Last edited by bogor; Oct 19, 2014 at 04:04 AM.
Racer
Joined: Jul 2004
Posts: 315
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From: Ornskoldsvik
Sorry to hear that!
Keep us posted, usually after a bearing failure you almost always need to regrind the crank. Sometimes the hole in the rod also warps and need to be rehoned for proper bearing clearance. I have some standard rods if you need.
/Svante
Keep us posted, usually after a bearing failure you almost always need to regrind the crank. Sometimes the hole in the rod also warps and need to be rehoned for proper bearing clearance. I have some standard rods if you need.
/Svante
Thread Starter
Instructor
Joined: Apr 2005
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From: Göteborg
Im using Eagle forged H-profile rods that should be plenty strong so if I'm lucky they have survived but thank you anyway for your offering!
Racer
Joined: Jul 2004
Posts: 315
Likes: 15
From: Ornskoldsvik
Those are pretty good rods. Should´nt be any problem as long the engine was´nt running to long after the incident. Measure the hole just to be sure!
Have you found the cause of the problem? A bearing failure is´nt that common, and does not occur without a reason.
Good luck
/Svante.
Instructor
Joined: Sep 2014
Posts: 169
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I've found the culprit now: no3 rod bearing is shot. I have not removed the pan so I cannot yet establish how bad it is but its possible to whiggle the piston up and down in the bore (I have removed the head). Lets hope the rod is still intact and its only the bearing. Could not see any metal in the oil but there's some on the magnetic oil pan plug. I also have a fairly strong magnet on the oil filter so hopefully all ferrous stuff has been trapped. Will see when I open up the oil filter. To be continued...
Thread Starter
Instructor
Joined: Apr 2005
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From: Göteborg
Well, I have pulled the pan now and its clear what caused the knocking sound:
This is what remains of no 3 rod bearing
It ended up in the oil pan, alot of shiny debris
At least the rod does not look over heated but will send it and the crank for professionell check.
I wonder what caused this?
This is what remains of no 3 rod bearing
It ended up in the oil pan, alot of shiny debris
At least the rod does not look over heated but will send it and the crank for professionell check.
I wonder what caused this?
Last edited by bogor; Nov 6, 2014 at 06:08 PM.
Thread Starter
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From: Göteborg
The bearing was moving freely on the crankshaft journal so I guess it could have been in any position. A guess is however that it was positioned at the bottom of the rod but I really don´t remember, sorry.