Roush Engine Failure – Pictures

[madmaxx]

The bottom line is NO manufacturer, engine builder or supplier intentionally installs a bad part. We play with some pretty expensive toys, I beleive this engine was in excess of $20K.

My first cobra had a run of the mill 302 with stock parts except for edlebrock manifold and heads and holley carb. That cobra and engine was beat senseless when I owned and the next , owner beat it harder. I am talking 1000's of 6Krpm shifts. I dropped the clutch 300 times? Next owner tracked the car. Last I saw it had over 15K miles and was still running great, used a little oil from what I was told.

My next one is going to have a stock engine, I'll give up the 75hp for bullet proof reliability and if it does break, who gives a sheet I only have about $4k into it!!!!

[Excaliber]

Max, I think your suggesting the rocker shaft itself was a "bad part"? If not, my apologies. It seem's clear the "defect" here was a loose nut, or several, which in turn resulted in a broken shaft.

[madmaxx]

The weakest link in any engine is the valve train. As we get more radical cams to squeze the last horsepower we have to go with higher spring pressures which in turn stress the pushrods, lifters and even the camshaft and turn the engine at higher rpm's. A stock 302 mustang has about 225 open and 100lbs on the seat. That is a far cry from the 400lb plus open pressures, probably higher with some solid lifters. Stock mustangs a go in excess of 150K miles. No replacement for displacement, if you want more HP get more cubic inches.

As someone used to say if you cant go fast with 100hp you cant go fast with 500hp.

As far as manufactures READ YOUR WARRANTY and note the limitations of liability, if you retorque bolts you may very well VOID the warranty. They are very explicit as to what you can do. In fact a smart person would read the warranty BEFORE they purhased the product.

This engine is out of warranty, bitter pill to swallow with less than 3K? miles but it appears the manufacturer fulfilled their obligation. Next time rack up 20K miles on the engine prior to it going out of warranty if it is going to have issues it will show up by then. If not you got a good 20K miles out of the engine.

[rodneym]

Darren posted this issue on 11/9 and he's getting the parts via UPS one week later. Not too shabby if you ask me. I know you're not going to get Jack Roush on the phone like you would Keith Craft or Tom Lucas but still, not bad. He keeps his KMP nice and shiny but he tracks it as well. Things happen to engines built by ANY builder.

Darren, weren't you getting a Daytona from KMP or was that a rumor? What are you up to?

[RodKnock]

What is the condition of the pushrods? For $750, you could get one of the last sets of the Erson roller rocker arm assemblies on the market from Barry R, so do the parts from Roush include pushrods? Those can be really expensive too.

Darren, you also mentioned that there may have been some internal damage too. Did you discover any, such as valves hitting pistons?

[madmaxx]

As I posted before the profit in these engines are comical, pick up a summit catalog and add up the parts, dart block, forged pistons, arp heads, scat rotating assembly, pistons, camshaft, timing gear, carb and these guys are making NOTHING, ZERO, why they do it is beyond me. Absolute best case scenerio on a stroked 351 using a dart block and getting 500 hp i bet the profit margin is less than $3.5K. Now the guy has to pay for his shop, his tools, his dyno, MY WARRANTY, a builder gets one warranty that needs 100% rebuild there goes his profit on the next 4 engines, oh wait, forgot about advertisement, machine work etc.

Originally Posted by rodneym

Darren posted this issue on 11/9 and he's getting the parts via UPS one week later. Not too shabby if you ask me. I know you're not going to get Jack Roush on the phone like you would Keith Craft or Tom Lucas but still, not bad. He keeps his KMP nice and shiny but he tracks it as well. Things happen to engines built by ANY builder.

Darren, weren't you getting a Daytona from KMP or was that a rumor? What are you up to?

[RodKnock]

Originally Posted by rodneym

Darren, weren't you getting a Daytona from KMP or was that a rumor? What are you up to?

I want to hear more about this new project too.

[Excaliber]

He's PAYING for the parts, why wouldn't he get excellent service and prompt shipping?

I would expect no less from any provider of parts.

Warranty: Yup, Roush has fulfilled the letter of the law, it's out of warranty. I can now write them off as any future dealer I would even want to do business with!! Fact remains, this is a DEFECT in workmanship, not a bad part, not a "stuff happens" moment, not a "bitter pill". This aint right, straight up, Roush should man up and take responsibilty, out of warranty or not. 2,000 miles? Violate warranty if you re-torque anything, and if you don't, you won't find out there is a problem?

Roush is done in my book. The thought, "a fool and his money..." comes to mind in that regard.

[N2VENOM]

Originally Posted by rodneym

Darren, weren't you getting a Daytona from KMP or was that a rumor? What are you up to?

My KMP LaMans fulfilled my needs for a hardtop. My next project was going to be the KMP Daytona, but decided on something a little different. David and I will be posting our plans in the next week. We are currently working out the details. My next build will be very very cool....

[rodneym]

Originally Posted by Excaliber

Fact remains, this is a DEFECT in workmanship, not a bad part, not a "stuff happens" moment, not a "bitter pill". This aint right, straight up, Roush should man up and take responsibilty, out of warranty or not. 2,000 miles? Violate warranty if you re-torque anything, and if you don't, you won't find out there is a problem?

Roush is done in my book. The thought, "a fool and his money..." comes to mind in that regard.

I don't believe you can quantify that statement. Did the builder simply not use torque specs? Did he not follow procedure? Maybe, maybe not. Very hard to tell. That's why a warranty exists. True, an indy builder will give you better service, I'll grant you that. But I've witnessed questionable service from small guys, too.
There's a local Cobra that had a HTOB give in 400 miles. Who's fault? Car exchanged hands a couple times and work was not covered by the installer.
Another Cobra with a name build had an engine that was un-tunable. Builder had specs all wrong. The local rework was covered but there's a term that came with it, "blood from a turnip". (BTW, the names have been omitted to protect the...innocent?).
Let's just say if Roush was involved in these incidents it would have been a witch hunt. I've seen builders literally coddled like invalids on these threads. Kudos to Keith and Tom and others who will cover out of warranty engines without hesitation but Roush isn't a mom and pop shop, for better and/or worse.

[RodKnock]

Darren, the OP, said this wasn't a "Bash Roush" thread. So, let's not get distracted and derail the thread guys.

[madmaxx]

Well said!!!!!!!!

Originally Posted by Excaliber

He's PAYING for the parts, why wouldn't he get excellent service and prompt shipping?

I would expect no less from any provider of parts.

Warranty: Yup, Roush has fulfilled the letter of the law, it's out of warranty. I can now write them off as any future dealer I would even want to do business with!! Fact remains, this is a DEFECT in workmanship, not a bad part, not a "stuff happens" moment, not a "bitter pill". This aint right, straight up, Roush should man up and take responsibilty, out of warranty or not. 2,000 miles? Violate warranty if you re-torque anything, and if you don't, you won't find out there is a problem?

Roush is done in my book. The thought, "a fool and his money..." comes to mind in that regard.

[dcdoug]

Originally Posted by RodKnock

let's not get distracted and derail the thread guys.

Now that's funny right there - .

[Excaliber]

Good on the OP not wanting to bash anybody. That leaves it up to me then!

How do I quantify that Roush's work is defective? Simple, the rocker arm shaft nut backed off, which resulted in a broken shaft. Now either the owner loosened it up or we believe him when he says he's never opened the motor. There is no history, that I know off, where FE rocker shaft nuts/bolts back off on their own WITHIN 2,000 miles of being installed. It just doesn't happen, that nut was not tight from the factory is the only reasonable explanation. PLUS, it was noted several other nuts/bolts were loose as well. This is very strong evidence of defective workmanship.

I'm sure open to other plausible reasons for such an occurance. I totally understand now wanting to bash anybody, dealers do take a beating, often undeserved. That does not appear to be the case here, from what we have heard (without cross examination) Roush is looking very guilty on this one. Not a bash, just the facts.

HTOB's are to risky for my taste, I don't care who makes it or put's it in, when it fails (and all to often they do) it's a nightmare of a repair job. Don't need the risk or the hassle.

[madmaxx]

There is never an excuse for a fastener to loosen. Fastener technology has been around for 1000's of years, LOL!!! Never had a fastener loosen on my Envoy, Lexus, gmc truck, bonnevilles, cadillacs, triumph spitfire, miata's, oldmobiles, mercruisers, mercury's cheverolets, I would guestimate 40 cars and 3 boats. I did have the carburator come loose on my sears crafstman blower one time, so I guess it is possilbe. It was covered under warranty.

Loctite is only one solution, there are different types of nuts etc.

Do we really know if a fastener loosened in this instance? The nut came off so did we find the nut? Not familiar with this valve train set up is the culprit set to a predetermined torque value or is it adjusted with backlash? I doubt something was left loose, wonder it something else is not going on, excessive deflection, vibration, thermal cycling etc.

[209]

Roush should repair it! I'm looking at a GT40 someday and Keith will have my business. And I'm not the only one. Bashing? Phooey! 209

[N2VENOM]

The nut was found off the stud when I removed the valve cover. The nut came OFF! This is my 10th cobra and I have never had a problem like this. Parts are on the way. Darren

[madmaxx]

So the nut was not on the stud, where was it? Is it in the oil pan? I guess it could not hurt anything, it would never get past the oil pump pick up screen, probably to big to go down the drain holes. I would just make sure it not hanging around somewhere.

I suggest checking the torque on the remaining ones, might want to torque the intake manifold bolts, as far as the rods and crank i would not bother unless you need to remove the oil pan to look for the nut

Originally Posted by N2VENOM

The nut was found off the stud when I removed the valve cover. The nut came OFF! This is my 10th cobra and I have never had a problem like this. Parts are on the way. Darren

[madmaxx]

As far as handling a claim past the warranty period, only one company has ever honored a warranty past the stated warranty. Including TV's, microwaves, engines, lawn mowers, boats, watches, firearms the only company that has gone well above or done anything after the warranty on what I consider a questionable issue on my part is SUPERFORMANCE. They will get additional business from me probably in the form of a GT40. I dearly love my Cobra but it gets HOT in Texas and air conditioning would be nice in the summer.

[Excaliber]

The nut in question is torqued to a specific amount after all valve geometry and clearance issues have been resolved. The intake manifold is already in place and bolted down to specs before the rocker shaft final assembly. The rocker shaft end stand adjustment's, to get the right height, is a crucial step. Once that is determined all rocker shaft support stands are then torqued following a pattern at a specific torque setting. Final valve adjustment can now be set and the rocker arm cover installed (button it up). If it's a "long block" (assembled block, heads and intake package, in the case of an FE) it is now ready to ship. Or, it is now ready for final assembly work, carb, injectors, dyno, etc.

As the rotating assembly would have been balanced previously vibration should not be an issue. Heat cycles should not have an impact on the shaft retainers and mounting assembly fasteners. Excessive spring pressures, due to a "wild cam" should not be a factor (providing proper torque specs were followed). All these things are taken into consideration by the rocker shaft assembly design. Of course some designs are better, stronger than others, but not generally the SHAFT itself, that is fairly "generic" to most FE's (and relatively inexpensive). If a shaft mounting fastener comes loose, for what ever reason, the shaft WILL break in a hurry. It is under a great amount of pressure, and has been carefully designed to handle it.

Re-torquing of these shaft components, while perhaps a good idea, is not called for. Checking for valve adjustment would be logical at about the 2,000 mile mark, some check it earlier, some later. In any case, there should be no valve adjustment actually needed beyond a few thousands of an inch. If the valves are out of adjustment very much beyond that, you have a serious problem. Like a broken rocker shaft or a receeding valve seat, loose fasteners, a bent push rod, a broken or worn rocker or numerous other causes.

I've never personally used something like "LocTite" on the rocker arm shaft nuts/bolts, perhaps it's OK if you do? Maybe I've just been lucky? I wouldn't say it's standard procedure as there is generally no problem with these nuts/bolts loosening up over time (especially at 2,000 miles). Rocker arm shaft re-torque is not a standard procedure, a good idea perhaps, but generally not required or noted as necessary in warranty paper work.

I am NOT a professional engine builder, just an above average "back yard" wrench I guess. I have not worked on a ton of FE's, so I'm not an expert. But I do know what is entailed here, what needs to be done, what should have been done. Based on that, in my opinion, it's defective workmanship on assembly.

Barry R., Kieth, Brent and many others could perhaps offer a better explanation or speculate more accurately on the cause(s) of this "loose nut". Most troubling here is the fact that other loose nuts were found as well. Maybe the motor was built on Friday, final assembly minutes before punch out time?

You may not actually SEE a broken rocker shaft on an FE, by the way. The engine, following a valve adjustment, may run well! You could go for many many miles before you figure out you have a problem. Often there will be no additonal damage to any other components. No metal debris through the engine, nothing that "stands out" and makes you look twice. It is interesting that in THIS case it was a sudden and pronounced failure that led the owner to conclude, "Wow, something just blew."