Worst Saturday I've had in long time

Also, Rod appears to have broke near TDC. Piston looks to be near the top and didn't get pushed down during the power stroke. Rings could have butted together and seized the piston.
AG.
 
Aluminum pistons expand much faster than the iron block. Was engine warmed up when boosting it?
 
turbobitt said:
Lesson learned, Don't use eagle rods in a stage motor.
Click to expand...
He bought this motor assembled from someone else. When we talked yesterday, we said it let go about 5 lbs on the footbrake. Surely the eagle rods alone aren't the cause.
 
I just had an R&D engineer look at this and he says it looks like the rod ripped away due to a stuck piston. Bore looks a tad scuffed too. He thinks a clearance issue or the piston heated up (expanded) way quicker than the bore due to the exhaust temps from building boost.
 
Ed Valvo said:
I just had an R&D engineer look at this and he says it looks like the rod ripped away due to a stuck piston. Bore looks a tad scuffed too. He thinks a clearance issue or the piston heated up (expanded) way quicker than the bore due to the exhaust temps from building boost.
Click to expand...

I'm a little surprised the aluminum piston wouldn't give up over the rod.
AG.
 
Look at the rod bolt in the very first picture!! Something shaved its head !!!!! Doesn't look like remaining rod section in the cylinder is close enough to have done that.

What could that rod bolt head have rubbed against to do that?????

There must be more missing rod section. Something was swinging around in there bad enough to bust up the block as bad as it is!!! What's left on the crank doesn't look long enough to have done it.
 
Mike E said:
I had the car in my shop a couple weeks ago building a downpipe and other little bits. While It was there I changed the oil and it had zero trash in the oil other than excess fuel from a previous stuck injector. Richard thinks it has maybe 500 miles on it before he got it and the most he and I had done was move it in and out of the trailer. It broke while he was spooling the turbo against the footbrake. What's left of the pin/rod/piston is seized up. What else could cause it to break a rod like that? It certainly didn't brake from too much power or rpm. I supposed there could have been a major flaw inside the rod, but even then it shouldn't have broken with almost no load unless the wrist pin was locked up.

I hate this for Richard because it's a really slick car with lots of potential and a really cool set of iron 14 bolt production style heads on it. It killed a like new 4.1 off center stage 2 block and frustrated the heck out of him.
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Just out of curiosity,did this happen to the same cylinder that had the stuck injector?
 
With it being an off center, was the rod installed correctly? I need to look at the pics again. I have never seen a block repair at that location. It can be repaired and put back into service.
 
I don't think it's the wristpin. Since you had a full floating pin it would have to seize in the piston pin boss and the rod before damage would occur. If it were the rings more than likely it would just tear the hell out of the cylinder wall when the ends butted together. If the piston to wall clearance was wrong it could probably seize the piston in the bore and end up like the pics you posted. Playing devils advocate if someone had set up the wall clearance tight as if you were running a hyperutectic piston instead of with the appropriate clearance for a forged piston you'd probably end up with the type damage you're seeing. I'd measure the other 5 bores and pistons and see what you find. I'd like to see at least .005" clearance myself.

My condolences on your motor Rich.

Neal
 
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piston was not stuck though I had to forse it out alittle due to bottom of piston contacting crank and mushrooming. rod on pin is free as well as rod journal.motor has run previously but only idling around and no I did not have a stuck injector I just had map hose on turbo port.was not reading vacuum.but did not run long like that and oil was changed after. iu am taking motor to Richard clarks for inspection and tear down.he want to measure everything.
 
Here's few mor pics. I was only 15 ft from my shop door when this happened. Motor was about 130degrees. But really should not have done this under such light pressure. I have beat the crap out of my old 109 and never had this happen
image.jpg
image.jpg
 
Rich brought this engine to my shop saturday ------- sunday i measured every single piece as if i were going to put it back together ------piston ring lands show no damage as would be expected with binding and or improper clearances------- virtually everything measured within acceptable values with the exception of the rod/pin clearance ------- normally for a floating pin i aim for 4 to 7 tenths ------- pin clearance on the broken cylinder measured 2.9 thou------ much looser than i would ever allow but i don't think it would cause this to happen especially in a turbo engine ------- the pin bore was also round so it wasn't enlarged due to being "hammered"-----------bearing/journal clearance on the big end of the rod reassembled with undamaged bolts was 2.8 thou and showed no damage------not what i would consider excessive for a stage motor with mondo oil pump like this one had-------big end of the rod was round and within spec--------- high powered microscopic examination of the rod it appears to have been "pulled" apart not twisted or bent to the breaking point --------bad metallurgy in an Eagle rod????? ------ that would be a first for me -------I can find no smoking gun..................... RC
 
thanks Richard for taking time out for my mishap,maybe we should send rod back to eagle...
 
A2000RICH said:
normally for a floating pin i aim for 4 to 7 tenths ------- pin clearance on the broken cylinder measured 2.9 thou------ much looser than i would ever allow but i don't think it would cause this to happen especially in a turbo engine
Click to expand...

I'm a little confused on how 4 to 7 tenths is tighter than 2.9 thous :confused:. What a shame if the connecting rod caused the engine to grenade. Well I guess it's a shame no matter what the cause.
 
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