Valve Guide Failure

[matteni]

That being said, modifying a car has inherent risks. Forced induction has inherent risks.

Call CompTech and tell them you are interested in buying a supercharger for your baby. Let us know how much time they spend telling you about the "inherent risks". Maybe you could write something up for them that everyone can sign first and they can post something officially here to prime about these risks. Great idea!

However, perhaps it was due to a foreign object entering the system when the first supercharger was replaced.

Is there anything that supports this hypothesis? We are talking about a unit that has been in production for a little more then 2 years failing and then another failing 1 month later after very little use. It was reinstalled by someone acting as an agent of CompTech who went through it very carefully at the owners expense to make darn sure there were no foreign objects prior to installation. I wish your version of events was true as it would be easier to prove the negligence.

These variables are the risks that the customer assumes when choosing to modify his or her car. Warranty periods are established by manufactures to accept a certain amount of risk of liability to cover among other things, the wear and tear on a product. Automotive aftermarket manufactures are at a significant risk from warranties due to the stressful environment of the automobile... heat, mechanical stresses, vibration, etc.

Are you suggesting we feel sorry for CompTech for so selflessly developing a product for profit, advertising none of these "features you describe", and then the instant something goes wrong - playing run and hide?

Their explanation of what they believed happened is as likely as your explanation, and maybe even more so since the engine was exposed to the risk of contamination with the intake manifold off again.

As likely as your explanation? Even knowing there were known manufacturing defects at Whipple around the time this super was supplied and there is evidence that other supers were replaced (sometimes proactively) to keep this thing from happening? In what universe do 2 CT superchargers fail in 1 month on a car that had been setup and tuned by CompTech authorized professionals and getting an ever changing "story" that only serves to cover their arses become a likely story?

The fact is, there are a huge number of variables, and adding a product like a supercharger exponentially increases the variables. The failure may have been heat stress or mechanical stress related. If it was heat related, the failure may have been contributed to heat stress caused by a forced induction product. The fact that the product was from CompTech would in this case be inconsequential.

As - here is that official story from CompTech I was hoping for - do you work for them? Maybe they have an opening in customer satisfaction? You can be department employee #1!

It's unfortunate what happened, especially with supercharger 1,

I agree with something the poster said! See I am not as cantankerous as people reading this must think!

however, it's obvious to me that CompTech went beyond any established level of customer service.

What exactly did they do to give you that idea? They initially said to the owner they would replace a failed supercharger 2 months out of warranty and have since taken back the offer and are asking for all the money. Please explain further.

To say that their explanation was "preposterous" (as another poster did) is ignorant to the variability of the situation, and the facts of manufacture liability.

Your post was the first use of the word "preposterous".

It's unfortunate what happened, especially with supercharger 1,

Ahh - 2 things we agree on.

 

[Yellow Rose]

Diverter Valve

.....maybe the diverter valve could be better placed.

Location and type of the valve is important. Someone had asked what type / style the diverter valve is. It is a butterfly valve that rotates on a stem in the middle of the valve throat. It is quite similar to the throttle body valve, only much smaller. It is approximately 1" in diameter, so when fully open, you can imagine that an object up to almost 1/2" can pass through.

 

[true]

Originally posted by AndyVecsey

No lectures needed....I have been working with engines longer than you are on this planet.

And? Sorry, I'm not impressed......

Missing a Vital piece of info here.

Such as ?

Dynograph with visable A/R is what i was trying to imply. I'm from the school of though that a person doesn't belong driving an aftermarket forced induction vehicle unless they've done tuning using a professional tuning tool (usually available at a dyno)

It's difficult to hear detonation, it CAN be silent

BS!

Have you read the SAE whitepaper on Gasoline engine detonation testing?? I have. There are many many different 'levels' of detonation, and you can not always hear it...especially over the sound of the engine. Unfortunately, it looks like SAE makes you pay for their papers now(??) so I can't link the article.


All valves are straight and all cylinders have the same amount of "sanding".

This is a clue to me, but I'll keep it to myself....I would imagine the sanding is moreso on the outside of the piston tops. (I'm also sure you'll say WRONG now, whatever the case may be)

Please go take a cold shower, you are quite clueless as to what really happened. You may know your stuff when it comes to tuning, but for purposes of this thread you are just going along for the ride. Sorry to sound so harsh, but when facts are laid out on the table and naysayers naysay, what is to be expected?

Gee, I'm sorry, I honetly THOUGHT the entire purpose of this thread was to share your thoughts on what happened and solicit ideas based on that. It sounded like you were 100% speculating on the story...I was just trying to bring a different possible view. I did not know you were trying to tell your theory as facts.

This theory of what happened is sound but very difficult to prove.

Interesting that you knock on me saying the FACTS are laid on the table and I am quite clueless as to what happened when all I can get clues from is the writing of your theory.There there are some facts, but you cannot prove how this has played out, and I thought it would be fun to speculate as you did. I guess you call me a naysayer? I love tracking down problems like this, it's right up my alley. I started all in good fun, but I suppose I'm not surprised you would once again act like an authority/cry baby. Anyways Andy, good luck. Let me know if you can't find that paper and want to read it...I'll get it for you after I get out of the shower. Thanks.

 

[Yellow Rose]

Cold Shower

I'll get it for you after I get out of the shower.

"true", I owe you an apology and will be taking my shower in a few. As Len3.8 stated in his post, he does not like to respond when he is "emotionally charged". Unfortunately, I did last night when I was. For that, I am sorry.

Pre-ignition and detonation indeed do come in various sounds. When I was refering to detonation, I was thinking of "knock" that is associated with poor octane.

If it matters, the original 6 PSI CTSC and upgraded 9 PSI CTSC were done by the same person, whom is a Comptech-certified installer and distributor.

As far as fact vs theory.

FACTS

There were no scratches on the rotors of blower #1 that concludes a foreign object entered.

There were pieces of debris from the engine in blower #2.

THEORY

Heat stress caused a valve guide to fail and via the divert valve and bypass tube to the throttle body, fragments found their way into blower #2.

Everyone - in the interest of fair game, rebuttals are welcome. However, don't just rebut and say this (only one so far) theory is monkey poo. Please offer an alternative scenario of how metal debris from the engine got into the inlet of blower #2.

 

[matteni]

I too have been too emotionally charged on this thread due to my own problems with an alternate vendor, my proximity to this case, and my relationship with another owner who purchased a CTSC on my recommendation who was treated very badly IMO.

Nothing like a cold shower and an hour of church with family to give you some cool down time and perspective.

I hold CT in high esteem, have lusted after their products, bought some of their products, and have recommended the CTSC many times - and expect (perhaps unfairly) that they always take care of the customer, not make me regret my recommendations, and error on the side of the customer. I shall hold all further comments and innuendos until the entire story and how it is handled unfolds.

 

[len3.8]

Hey, It's all okay. You guys have made me feel good. I know that people on this board are passionate about each others well being. That says a lot. Opinions provoke deep thought, gives you another way of looking at things. It's nice to know you have friends, even more amazing when you have never physically met some of them.
I begin my quest tomorrow.
Len

 

[KGP]

There are many many different 'levels' of detonation, and you can not always hear it...especially over the sound of the engine.

I have been wondering about that very possibility this past week, and not because of the happenings in this thread. While a few tempers flared, this thread is one of the best reads in a while. The exchange of this kind on information is one reason Prime is heads and tails above other forums.

As with Len3.8, I too have a quest that starts tomorrow.

 

[sjs]

In case anyone missed or forgot it through all the noise, read this again:

Hello All, in most 4 stroke motors there is a condition called reversion, this is when one cylinder is on the intake stroke and it is pulling vacuum from other cylinders, it is very possible to pull pieces of metal, aluminum, or any foreign objects from one cylinder to another, this would also allow even oil passing from one bad cylinder to go up into the intake and find it's way to other cylinders, also coating the inside of the intake manifold with oil.

That sounds like a far more believable explanation, coupled with Andy’s point about the diverter valve, for debris getting from a combustion chamber back up to the SC. While I’ve heard/read about reversion in the past, it was related to carbureted engines and I must say I’d long, long forgotten it. Thanks for the input Gerry! I’m still not totally on-board with valve guides be the culprit, but nor would I rule it out.

Here is one explanation I found on the web that follows my somewhat hazy memory on the subject:

Reversion, what is it? It is simply the exhaust pulse flowing backwards momentarily during the overlap phase of the camshaft at low cycling rates. During the overlap phase the piston is pushing out the last of the exhaust gases and prior to reaching top dead center (T.D.C) the intake valve and the exhaust valve is still closing. At this point in the engine cycle both valves are in the open position. At high cycling rates the inertia of the incoming intake charge and the outgoing exhaust pulses keep the exhaust flowing in the proper direction. But at low cycling rates, as the piston is pushing out the last of the exhaust gases the intake valve opens and some of the spent exhaust charge is pushed into the intake manifold. As the piston reaches T.D.C. and begins the intake stroke the exhaust valve is still not completely closed. As a result, the piston pulls from the intake and exhaust valves simultaneously causing the exhaust gases to flow in a reverse direction. This is normally not a problem until you add water into the exhaust stream. Reversion can be severe enough to stall the engine, add water to the oil, rust the exhaust seats, etc. This effect only happens at idle speeds, but remember that during shut down the engine encounters the greatest reversion.

 

[len3.8]

Well, what I expected from the stealership has happened. " We are not associated with Comptech" The unit was not purchased through our dealership so we are not at fault. We will tyr to work with you on the additional costs. They are trying to say that the screw ups that they may have made couldn't give ne the results that I have now. Well now to get the unit off and see what's going on iside.
Len

 

[sjs]

Len,

Are you planning to open it up somewhere other than at the dealer? Then it becomes your word against whatever they prefer to believe, and we already know how that ends. At a minimum we need to have witnesses and pictures/video.


Steve

 

[len3.8]

I will stick to my word, even if they will not. I will do it at the dealer. I was going to give you a call and check your schedule.
I do plan on some complete documentation. I will not let them do much else, though I doubt that they want to now. I have told the service manager that a 3rd party of my choosing will be present.
Len

 

[sjs]

I have just edited on of my earlier posts where I stated incorrectly that the intake valve guides protrude from the head casting only a very small amount. Now that I have it cleaned up and in better light I see that the guide does in fact hang down quite significantly. Sorry for the error. That doesn't mean that a broken guide is the cause of Len's SC problems, but it does further reduce my skepticism of the possibility.

 

[grippgoat]

First let me say I don't know jack shit, so if I'm off base, don't waste any efforts flaming me or anything. Just tell me to shut up, I won't take it personally.

Andy made it sound like nothing was really done to clean/fix the engine after the first blower failed, and that it was run still having little bits of metal dust after the first blower siezed... Doesn't that seem rather odd? It seems especially odd to try and re-subject a compromised engine to forced induction.

Also, I would suspect that the reason Comptech was readily willing to replace the first blower that had bearing failure was precisely because of the known bad batch of blowers. If in fact the engine was simply slapped back together after the first failure, it would be understandable that Comptech wouldn't want to warranty things further. But of course, the right thing to do would have been for Comptech to help make sure the engine got properly repaired after the first failure.

As for the valve guide failing... Maybe normal supercharged heat wouldn't seem so high as to cause undue stress, but with the bearing in the first blower failing, wouldn't that cause it to produce substantially more heat?

I was also wondering if maybe vibration from the failing blower #1 could have come into play, since the blower is bolted so directly to the engine.

-Mike

 

[sjs]

Mike,

No flames here. he first two paragraphs are reasonable observations, but I don't recall the exact series of events so I'll need to reread that. The last two ideas are a bit more of a stretch. The heat involved is from combustion and at such a level that a few degrees from a warmer blower housing would be irrelevant. Running a bit lean on the other hand will greatly increase temps around the valves. Likewise vibration from a blower bearing which I wouldn't expect to have any impact on valve guides. Of course, harmonics can do amazing things, but I think it's a stretch.

 

[Yellow Rose]

Andy made it sound like nothing was really done to clean / fix the engine after the first blower failed, and that it was run still having little bits of metal dust after the first blower siezed.

Correct and incorrect. Correct in the sense that nothing was done to fix the engine at that time. As stated, the damage was done and would not worsen except the by the effects of mechanical wear-n-tear over time. Incorrect about the metal dust remaining behind. Before the replacement blower was unstalled, with a flexible metal tubular wand, the intake manifold, intake runners and tops of the pistons were vacuumed out. This was done to all six cylinders by hand-turning the engine to sequentially open up the intake valves. Debris extraction was verified with a mechanic's boroscope.

Doesn't that seem rather odd? It seems especially odd to try and re-subject a compromised engine to forced induction.

Not really. There was nothing mechanically jeopardized that would subsequently break due to forced induction. For example, no rods were cracked that would've lead to future failure under boost. No bearings were scratched and the crankshaft journals were ok. So the only thing that resulted was slight loss of power because the compression test and leakdown test both failed. Other than being down on power because of low sealing in the combustion chamber, the engine was not compromised, per se.

If in fact the engine was simply slapped back together after the first failure, it would be understandable that Comptech wouldn't want to warranty things further.

The engine was not "slapped back together" because other than the intake manifold, nothing else was disassembled. CT was in the loop the entire time, and if they wanted to object to the steps taken, they would've / should've said something.

 

[nsxtasy]

Debris extraction was verified with a mechanic's boroscope.

From the FYI department...

I had never heard this word before, and so I looked it up. The dictionary has it as follows, with the spelling of "borescope" (which makes more sense for its two-syllable pronunciation):

One entry found for borescope.

Main Entry: bore·scope
Pronunciation: 'bOr-"skOp, 'bor-
Function: noun
Date: 1941
: an optical device (as a prism or optical fiber) used to inspect an inaccessible space (as an engine cylinder)

 

[NetViper]

I think it is funny how you can bash the comptech system in public, but everyone has to be hush hush on all the problems with the BBSC.

 

[Yellow Rose]

Not True At All

Do a search, and you will find some very candid comments by Kendall Pond and Bryan Zublin about their opinions on the BBSC. Yours truly - a customer of both systems - has commented on the pros and cons of each kit. In fact, I recall a post a couple of months ago by Mark Basch himself, explaining the growing pains of the BBSC.