Forged Redeye Engine Failure :( Why????

[16GoManGoHC2]

If it was an oiling issue then the cause is not with the main caps. What do the journals on the crank look like. What do the oiling ports on the journals on the crank look like? The caps have one purpose, that is to keep the crank attached. That's it. What do the bearing journals look like?

The oiling issue was because with the cap pushed off it seat the crush on the bearing shells was not there any more and the main bearing shell rotated just enough to close off oiling to the journal and up to the rod journal and caused a rod failure. If the studs would have been strong enough to keep the main caps in place none of that would have happened. Root cause was main studs did not hold caps down tight and allowed other things to happen because of that. The witness marks on the caps says it all, they were doing that for a bit before things progressed to failure. They were ok at 1000 and 1300 to the tire but did not like 1500 to the tire. The purpose of this thread was to point out the weakness of this engine that lead to failure was main studs due to material type were not up to the power level being made.

 

[16GoManGoHC2]

Maybe it was a material rod failure. It just let go, kaboom. Possible

Boostline rods do not usually fail without reason, they are pretty beefy rods made from some of the best steel you can get.

 

[16GoManGoHC2]

If it was an oiling issue then the cause is not with the main caps. What do the journals on the crank look like. What do the oiling ports on the journals on the crank look like? The caps have one purpose, that is to keep the crank attached. That's it. What do the bearing journals look like?

Journal on the crank looked fine, journal on the rod did not, was starved of oil due to the bearing rotating about 30 degrees from where it should have been.

 

[stonewall]

How much time was put on it at 1500hp? I'm trying to figure out how long it took to do the damage to the caps. we are assuming that it all happened at 1500hp because that is where it finally failed. but do we know it had not already incurred damage at lower numbers as well. I have built many engines, Not high end performers like this. but the principle is the same. the caps especially the rear main, looked nearly new in the bearing saddle, with know ride marks of the shell like the others have. which makes sense as the load was probably more on it under load and would have stretched it first I would think. but as you stated the failure was when the shell spun, the clearance could have been excessive long before the tang gave out and let it slip.

 

[Jack_Toepfer]

Main bearing spun, blocked off oil to the main bearing, starved crank and rod of oil. No heat in the cap, no sign of the bearing spinning on the cap. What am I missing? Can you show a picture of the rod that failed from lack of oil?

 

[16GoManGoHC2]

Main bearing spun, blocked off oil to the main bearing, starved crank and rod of oil. No heat in the cap, no sign of the bearing spinning on the cap. What am I missing? Can you show a picture of the rod that failed from lack of oil?

Bearing only moved about 30 degrees, just enough to move the oil inlet slot and close itself off, did not fully rotate and spin. that crank journal had enough oil to lube itself enough but nothing up to the rod. The rod somehow side welded itself to the crank and spun with the crank and sheared itself off on the block and then spun with the crank like it was a welded on balance weight. Weirdest failure ever!, windowed the block, did not even damage the crank visually but it was not reused.

 

[16GoManGoHC2]

How much time was put on it at 1500hp? I'm trying to figure out how long it took to do the damage to the caps. we are assuming that it all happened at 1500hp because that is where it finally failed. but do we know it had not already incurred damage at lower numbers as well. I have built many engines, Not high end performers like this. but the principle is the same. the caps especially the rear main, looked nearly new in the bearing saddle, with know ride marks of the shell like the others have. which makes sense as the load was probably more on it under load and would have stretched it first I would think. but as you stated the failure was when the shell spun, the clearance could have been excessive long before the tang gave out and let it slip.

Yes, with the caps pushed open the vibration from the caps unseating and then seating themselves hundreds of times a second it’s thought vibration and oil pressure hydraulically loosened the bearing shells in the bore and they started to rotate and blocked off oil path from the oil galley. It did not take long, failed on the Dyno during the use all boost made 1500+ dyno tuning session.

 

[Spoolin]

The oiling issue was because with the cap pushed off it seat the crush on the bearing shells was not there any more and the main bearing shell rotated just enough to close off oiling to the journal and up to the rod journal and caused a rod failure. If the studs would have been strong enough to keep the main caps in place none of that would have happened. Root cause was main studs did not hold caps down tight and allowed other things to happen because of that. The witness marks on the caps says it all, they were doing that for a bit before things progressed to failure. They were ok at 1000 and 1300 to the tire but did not like 1500 to the tire. The purpose of this thread was to point out the weakness of this engine that lead to failure was main studs due to material type were not up to the power level being made.

You were using 260k+psi none tapered studs, correct? Better than L19, which can corrode over time.

Very odd that they stretched beyond their clamping force, unless they weren't actually torqued properly with good lube in the proper areas.

 

[jgilj]

Reminds me of counterfeit parts that was a big problem in the airline business.

 

[16GoManGoHC2]

You were using 260k+psi none tapered studs, correct? Better than L19, which can corrode over time.

Very odd that they stretched beyond their clamping force, unless they weren't actually torqued properly with good lube in the proper areas.

That engine had standard grade ARP 8740 material studs in it, they are like 190-200,000 psi tensile strength. Engine needed better is the moral of this thread.

 

[Bowtie Guy]

Its Trumps fault