Yeah.. broke the crank

[gnman87]

So, no the timing chain.. or head gasket. Broke the crank. Never heard of this under such low load. The only numbers I can see on the crank are:

CFD 161 on the first journal which is where it broke.

Is that a turbo crank? Where can I get one at a reasonable price?

How the hell did it break?

thanks
jp

 

[mytquick87]

You should have rolled fillets on the mains and rod journals- if not, its not a turbo crank.

 

[REDS HOT AIR]

back off the rockers and be sure cam spins freely

also rotate the oil pump shaft and see if it spins freely

 

[TurboDave]

Originally posted by gnman87


How the hell did it break?

thanks
jp

Do you know the history of the car/engine? Maybe it was horribly abused before you got it.

 

[TurboJim]

I wasnt beating on mine when it broke. Rolling onto a highway... 5psi tops, TCC was even locked if I remember and poof!

Probably was hurt and it was just time to go. Thats what I thing about mine anyway. I am not easy on my car when I do drive it!

 

[Ormand]

I broke the crank in a 302 Ford, in a Sunbeam Tiger, years ago. (before the engine became the 5.0 liter) I was going about 30mph in third gear, maybe 1500, 1600 rpm. Oil pressure light came on, and I kicked in the clutch, and coasted to a stop. Engine was locked tight, by then. Pulled the engine, and put on the shop floor. When I tipped it up onto the bell housing to pull the pan, I could hear things clanging around inside, and I knew I had big problems. The broken crank ripped the center two mains out of the block! But it didn't bend a single rod, or a valve. There was an undercut on the cheek of one crank throw, and a fatigue crack worked its way through. Engine had maybe 15,000 miles on it. It had many chances to break at 4,000 rpm- or more- in 4th gear, but it waited for a "good" time. You never know...

 

[gnman87]

Hey guys.. took those numbers off of the first journal and called Brian Weaver -- and low and behold.. not a turbo crank. N/A and broke rather easily.. so, probably already damaged when I got it. Sucks.. but, got the right one on the way... let's hope nothing else broke.

jp

 

[opeltwinturbo]

I broke two stock cranks in my 86 GN and attribute it to the #16 transbrake launches. Trashed both blocks and most of the internals. Each crank lasted about 20 passes. Went to a girdle and have not broken one since. Still launch at #16 and pull the wheels about 6-8". Car has gone 10.95 @ 124.

John Schmidt

 

[1owner]

I broke mine a couple of weeks ago. I had 193,500 miles.
I was running mine hard when it happened. Spun the tire in 2nd gear w/ 15 #'s boost [hit a wet patch, and rrrrrrr].

Should be back on the road by the weekend.

 

[gnman87]

right.. only problem is.. this car has 80k.. the engine allegedly only 15k or so. I contacted the prior owner.. and he says.. "of course it's a NA crank. It's a Jasper's engine." I asked what other internals were potentially a problem.. he said, "The heads and valves aren't specific to TRs.. so, you should be fine." Whatever. The heads are, in fact, specific, aren't they? Any other worries I should have putting this car back on the road? Thanks

jp

 

[Grandnat]

Originally posted by gnman87
[B The heads are, in fact, specific, aren't they?

[/B]

No.


the crank, Pistons, and cam are really the only major differences besides the obvious. (Intake, turbo headers etc)

The heads are the same.


You can now get an Eagle crank for a very reasonable price and it will be MUCH MUCH stronger than even a stock turbo crank.

besides, the more people that buy Eagle cranks, the more likely they will continue to manufacture them and that will raise the chances of us getting them to make us a cheap stroker in the future!!!!



however, to be very honest with you, I wouldn't be afraid to put an non-turbo crank back in it. They are dirt cheap and have been proven to last deep in the 11s and even 10s. Your broken crank sounds like a bit of a fluke.

but if you want the peice of mind, buy an eagle crank and never ever worry about that problem again, last time I checked they were around $550 or so.

 

[Red Regal T]

I have a freshened short block with an NA crank sitting on an engine stand in my garage, waiting for catastrophic failure of my present motor. I'm putting off the catastrophic failure as long as possible.