LS6427

iTrader: (2)

173,000 miles on my stroker....so I can't complain.

I was doing a very high speed run on the highway yesterday. Out of nowhere the engine just shut off dead like I turned the key to off. No noise, no vibration, nothing.......

I pulled over and the temps were 240*F and there was white smoke pouring out of the oil fill cap when I took it off.

Engine turns over but its struggling, not smoothly turning over. But it will not fire.

Any ideas why it won't fire? I'm thinking my oil pump failed during the run....

Engine comes out this week. It'll be rebuilt immediately into a 441ci LS7 top end.

VIDEO:
UPDATE....video...turning over engine. Its not just one speed, it sounds like it has a little struggle spot.

http://s263.photobucket.com/albums/i...idstarting.mp4
************************************************** *******

UPDATE 3....Video.........Internal Part is broken..........

Video is short......put the new Crank Sensor in. It fired like it always has when I just bump the key. BUT...it made an instant loud, CLACK, CLACK and stalled by itself. I did not try again.
I'm guessing broken rod.

There's a picture below of the old Crank Sensor....it has about a 1mm deep groove across it.

So, engine is coming out.......getting rebuilt. SUCKS, its just a bad time. I was about a week away from getting my new (used 2008) Merc E63 AMG.......now I'll have to wait maybe 6-8 months Oh well........pay to play. I got to play for 10+ years with this great engine that ARE built. Hope my 441ci lasts this long.........

VIDEO:


.

Starkey

any water in oil or visa versa? My gut reaction is headgasket failed and it hydrolocked.

LS6427

iTrader: (2)

No water in oil. My builder said to check if the timing chain broke. See if the rockers move when I turn it over. Maybe thats why no spark. It has plenty of fuel pressure.

How about a fuse for the ignition system, is there just one fuse for that?

.

Starkey

Hope that's all that happened! And yeah, there is a fuse for the ignition under the hood (on my Silverado there is anyways).

Pull a sparkplug, plug it into its coil wire and have someone crank the engine over while you look for a spark from the plug. That'll tell you right quick if you're getting spark.

LS6427

iTrader: (2)

I'll check that tomorrow. Car is at a friends house. I had it towed there because we can pull the engine there if need be.

I thought I'd be pissed about this happening some day.....but its a great reason to pull it and rebuild it. Its old..... Just sucks because it ran so damn good.


.

Starkey

Hahaha! They always run the best right before they let loose!

LS6427

iTrader: (2)

I'm still thinking maybe the oil pump failed.

Do you know what happens when an engine is at high rpm and oil stops flowing....?

I mean does it usually end up in a catastrophic failure with parts breaking and noise. Oil pouring out of the crankcase. Will it still turn over if it shuts down because of oil starvation?

.

Starkey

Meh.. when it's at high rpm and oil stops flowing, it usually just seizes up before parts break. If the oil pump did fail, it probably seized the bearings and rings momentarily. Once the engine cooled somewhat, it freed itself and was able to turn over. Now, as far as the white smoke pouring out of the oil filler cap, that's a sign of major blow-by. If the engine was in the middle of seizing, the rings were getting pliable and lost any shape they had, letting oil get by the rings and into the combustion chamber, and gas and burned oil from the combustion chamber into the crankcase, thus giving you the abundance of white smoke.

How high were the rpms when it let loose?

DONAIMIAN

iTrader: (18)

If it was the oil pump, the new hole in the side of the block would have told you so

LS6427

iTrader: (2)

5,500 - 6,000, over 150mph.

It shut down very quietly. No other bad symptoms.

.

LS6427

iTrader: (2)

No oil coming out anywhere. All looks fine.

A failed oil pump will always put a hole in a block.....????

.

NC98Z

iTrader: (1)

You could have a bad fuel pump. If it has lost fuel pressure I don't think it will even try to fire. The first thing it does before you start it is prime the fuel pump. Probally the white smoke is just from the high speed run you were doing.

LS6427

iTrader: (2)

Fuel pressure seems good. I didn't use a tester, but I can hear the fuel pump prime normally like hit always does when the key is turned to "on". Fuel blasts out hard from the fuel rail port when I push the pin in.

I have to get back over there tomorrow and check the fuses, then see if the rockers are moving to see if the timing chain broke. I'll pull a plug to check for spark while cranking.

.

DONAIMIAN

iTrader: (18)

Not always, but if you're turning any decent RPM when it happens it's a good chance. Doubt its a timing chain, every time the motor turns over you would run the valves into the pistons and that noise would be obvious.

LS6427

iTrader: (2)

Huh....well there's no hole in the block. If its not the timing chain then maybe just a fuse blew for the ignition.

.

Starkey

your muffler bearing failed more than likely.

Keep us posted.. and get a vid if you can!

RonSSNova

iTrader: (3)

No oil pressure at full throttle is catastrophic. The rod bearings will fail, the friction will turn the big end of the rod red hot, then boom! One or more will break, and there is the hole in the block.

At full power an engine will have no problem overcoming the friction caused by no oil pressure.

If you have an oil pressure gauge, you should see pressure when cranking, or just after you stop cranking breifly.

LS6427

iTrader: (2)

If it was catastrophic......and a rod broke. Would it be silent? Would I hear metal banging around now when turning it over?

My oil pressure gauge has never moved until the engine actually starts up, about 1 second after its started and running the oil pressure needle jumps up. Been that way since my 427ci went in 10 years ago.

.

Exeodus

iTrader: (1)

A quick way to check if the ignition relay went is to swap it with the fan relay right next to it. If it fires, you found your problem. Both are located in the fuse panel behind the driver side headlight.

LS6427

iTrader: (2)

Cool thanks....so its one of the big grey block type fuses......not a little plastic one. I'll try tomorrow.

.