Does something not look right?

[Donunder]

Originally Posted by Tengu

Haha Treeve. I'm sure I'm doing everything right. Oh well...I apologise to all for any future post I add trying to sort this out. I've checked the link so many times and followed Sticky's advice and all looks ok.

Well mate the pictures may have finally come through but all, most assuredly, does not look OK..!!!

What a mess. Feel for you.

[Aussie Mike]

Originally Posted by Treeve

nope, lots of broken images.

So under the thread title of 'Does something not look right" I reckon the posts count!

Treeve

Lots of broken parts now

Any idea what caused the failure. It looks like the rod went big time. Was it big revs?

Cheers

[Tengu]

Thanks Don.
Mike, I wasn't revving at the time, but could have been from an earlier run.
I was just heading back home on the M1 at about 100kph. The car just didn't seem right and stalled on an off ramp. So once started again I headed home. The water and oil temp were up just a bit, but didn't come back down when in fresh air. Lucky, I was actually covering the clutch at the time because I was in limp mode. To be honest, its probably a good thing it let go because I would have been spending months to figure out what was wrong. The motor actually felt a bit tight and just didn't quite seem itself. No noises or rattles before it let go...just didn't feel right if you know what I mean.

[Tengu]

Looking at the parts, I'm presuming the bearing was dry because its well and truly stuffed. The rod big end was really loose even though the nuts were still tight. I'm guessing that's what made the rod stress and part ways?
The head looks ok even though the piston hit it a few times. I will have to check the valves. They look like they seat ok but cant be sure. Crank is scarred and I haven't pulled the cam yet to see if that's ok.

[Russell9318]

Wow, I think we have a problem Houston.

[Gaz64]

I see a few things.

How wide is the bearing shell in relation to the conrod cap?

Is the wrist pin free, or binding up?

If the oil feed in the crank blocked up, you get a dry bearing that seizes to the crank pin, then the whole bearing spins in the rod.

If the oil doesn't flow from the bearing due to tight clearances in the fillet radius of the crank pin, you may still have oil pressure at the bearing but no flow to cool the bearing. No flow is as bad as no pressure.

The conrod shows it has overheated (blueing), and subsequently fractured. It shows the rods aren't up to the task required.

All of this happened in an instant, and could have been from previous high rpm use.

Generally when that sort of failure happens, the camshaft will also be damaged.

Your heads should still be ok, but the valves in the offending cylinder would be bent.

On disassembly of the rest, I would check the rod side clearance on the front 6 cylinders. Once you have the rods out, I'd measure the bearing crush within each rod bore.
I would also look at the good cylinders bearing shell chamfer to crank clearance. Something will pinpoint an assembly clearance issue.

[750hp]

Engine carnage is horrible but beatifully fascinating all at the same time. Sorry it had to be you that encountered the carnage. I agree with everything Gaz mentioned and would also add that the crank won't be very happy after that. If it's blue as well as scarred, I'd be planning on turning it into some garage wall art...

[Tengu]

Thanks Gaz. Bearing shell looks like it was compressed and spread out, so is obviously wider. Wrist pin is free.
Craig I've got lots of trophy goodies for the garage wall now

[Dimis]

Oh no!
That looks nasty.

Might I say you seem to be taking it quite well...
I'd be inconsolable for... Well, for an extreeeemely long time!

[MaSnaka]

I am sorry for your troubles. I have to agree with 750HP "Engine carnage is horrible but beatifully fascinating all at the same time." I would look at this as an excuse to go bigger, better and more power. Thanks for posting and good luck.

John

[Clois Harlan]

I see the pics just fine and I did the exact same thing on my old 428 FE at Texas Motor Speedway. The ole engine couldn't handle much over 6500 RPM on a banked race track. I pushed mine to almost 7000 when it let go. Eriely quiet when that happens at 150 or so mph.

Good luck with your new build.

[750hp]

How's the replacement motor coming along?

[Tengu]

Yeah Dimis, usually these things don't upset me so much, it's dealing with US engine builders that is the annoying part. Having said that I'll be really dirty if this new engine craps itself.

I agree MaSnaka, it was an excuse to go bigger and better, and with the wife's blessings (to a point).

I am fortunate Clois that mine blew at 60mph, not 150mph, that must've been bloody scary.

Craig the new long block is now in my garage, you can see it in the background of the first of the current photos. 428fe stroker.

[750hp]

Hi Tengu. How are you progressing with the heat shielding and engine installation?

[Dimis]

Originally Posted by 750hp

Hi Tengu. How are you progressing with the heat shielding and engine installation?

I'm interested also.
Particularly with what you may have done to manage heat with regard to fluids and heat from the exhaust headers.

Thx.

[Tengu]

Since last posting, I've had a crap load of stuff going on and haven't had time to do anything to the car. I haven't purchased any heat shielding yet, but whichever one I go with, I hope it works as well as the old one. It's only installed on the firewall and trans tunnel, and I have no issues with heat in the cockpit. The headers are ceramic coated, so maybe that helps.

[750hp]

Hope things settle down soon to allow you some time to tinker with that beautiful Cobra...

[Tengu]

Thanks, Me too !

[GregAgrest]

I'm seeing all the pics and they are not a good thing. Sorry for you problem Tengu, looks like a new engine in your future. How many RPM's were you turning when it happened?

[Tengu]

Greg, at the time I was only doing 60mph (100kph) at somewhere between 2500 and 3000 revs