Just for the record, I have never blown an engine... I mounted a tire once, but that's quite a different story.



Eric

deside contamination in the fuel is there anything else to look for... i.e. color or ?


or the terrorist who was sent out to blow up a bus... failed because he burnt his lips on the exhaust pipe

sorry, had to follow the lead here

Couple of short stories about bad gas....

When the wife and I were first married we went to Florida, on the way we filled up at a discount store. Car ran so shit I thought it was about to blow. At half a tank I pulled into a name brand station and filled up with super. Within a couple of blocks the engine ran fine again.

10-15 years ago A discount gas station in Toronto got caught dumping toxic waste into gas. They figure it had been going on for a long time, but the creeps got greedy and put too much in. Whole whack of blown engines traced back to them.

....and stale gas... I`ve seen seized valve guides on a few aircooled engines (not just VW).

Bla,bla, bla

Another form letter I've seen before, full of invective & specious logic.
I can name call also, Jake. You want a taste? It would have to be off line as it is against the rules here. Oh, I forget, you're tight with the admins and rules don't apply to you.

I have experienced detonation from an air cooled motor. I couldn't hear it but I could feel it. I quit pushing hard up hill in 3dr gear. No rods popped out of the case....go figure.

Whoa! Alfred is back!


Oh.... it`s only JP ragging on Jake..... yet again....

We all know you`re a T4 hater....what else is new.

Long sweeping right hander at freeway speed. No detonation heard, no change in feel. Just pop, smoke, oil spray... Still ran on the three remaining cylinders. Oh, and no rods popped out of the case... that was piston shrapnel. Same with the wood chipper. Piston blew up. The gas is discolored and separates when you put it in a container into two distinct solutions. Even without analysis I'd say that it is bad. It isn't supposed to do that.

I am having a hard time finding your point. Are you a better driver because you felt the detonation? Was the engine better because it didn't blow? Rhetorical of course. I don't really care about your answers.

You like six cylinders. We get that. Your always bagging on California and Jake and Type IV motors. We get that. I built this motor. If you want to insult someone pay attention to me. I'm the one you'll piss off. And you can

Hell yes... Last time I checked I could handle anything that any mortal could throw at me. Bring it on.

...."As I walk through the Valley of the Shadow of Death I will fear no evil, for I am the meanest son of a bitch in the Valley."

That quote hangs on the wall of the Bathroom in my shop... Non hackers who do not pack the proper "gear" love it.. But not very many of those visit here and they generally leave rather quickly.

Though Robby's engine did break and even though it was due to bad fuel, it helps to make up my failure rate of less than 1% over the past 15 years... Porsche doesn't have a record that good with the M96 engine, about 5% of those fail before 40,000 miles and thats why I am enjoying working with them... I only like to work with engines that are black sheep, misunderstood and generally considered junk by the closed minded.

I'll take a 1% failure rate anyday, have 800 engines pass through your doors JP and see if you can maintain 1% with your name stamped on them.. Start now and report back in a decade and a half...

Oh yeah, make sure that at least 50% of those engines produce DOUBLE their stock power rating....

Am I the only one that had to look up invective and specious.

No. JP is looking it up right now...

Yes.

You know inaudible detonation will blow up a motor too? True story! Sometimse you do not even feel it until it lets go. This is why we have this new technology called a "knock sensor". Say it with me.

Here is what light detonation does to beefier rods at about 350ftlbs of torque! This is a solid cast iron block at that.





This one was 5th gear detonation cruising at highway speeds!




Here is another hint, if you can hear it detonating the damage is already done. That load + the engine load = failure of components. Not too hard to understand is it?

Second hint, the guy with the issue blew up lawn equipment with the same gas the car was running when it popped.

Astounding jeeves!

Geez Rob, its been awhile but sorry buddy. If you need anything 2.0 related let me know... my stash o parts is your stash o parts..

So is the catastrophic failure due to bad gas left in the cylinder and heat exploding it at the wrong time? Sorry for the dumb question.... still not sure what exactly detonation means...

Does a particular fuel filter help prevent something like this? or do mere mortal 2.0s have less to worry about?

A filter collects contaminants... It doesn't know if fuel has the proper flash point or octane.. It will catch some water that can collect in fuel as well, but thats about it.


Detonation is just that, its an explosion within the chamber, not simple flame propogation thats "controlled"...

Very good of you Jake- we will be watching for progress soon~ Hope it comes back together without a hitch. I will be sending some biz your way Jake, in the not too distant future. Thanks for being supportive-Jzn

i bet you have a type IV!... oh yeah, i do too

mike

OMG... what the heck is your problem? Oh... I know I know... Jake is better than you and just can't take it!! Well, you know what? Its OK, theres counseling for those types of disorders.

Jake has done nothing but great things with the Type IV motor and his customer service is second to none by a long shot!!! If your beef is with the Type IV in general, then why don't you go send your complaints to VW.

Excuse me... I have another crying baby to attend to... my 4 month old.

-Rob

It's funny how sensitive these motors can be sometimes and how tough other times. You have to remember that you're dealing with a small amount of material here. If something is creating excess heat or stress, there isn't much outlet for it other than to break things in a hurry.

You're at a serious advantage here because your 6-cylinder is so much heavier.

Detonation is fuel igniting when you do not want it to, pre-ignition. Some folks use the terms interchangably.

Basically, your crankshaft is moving up, your rod is moving up, and the charge ignites on a hot spot somewhere, this explosions creates a nasty pressure wave that is pushing back on the stuff as it is coming up.... That pressure wave plus the force of the rising piston/rod/etc is a LOT and too much for the motor to handle. Metal has it's limits.

Look at the broken rod above, the pistons in those motors will be fine to 650hp at the front wheels. That is the limit someone has reached. I have been driving on stock rods with 400hp, everyone tells me I should have thrown one. Well I have not because I am very anal about my tune.

Go look up how much force a piston/connecting rod is under as it's moving at 3000rpm.

This "pre-igniting" your mixture exerts loads on the metal that are way over normal combustion and etc.




Detonation can do that too, sometimes things do not always break. The type IV case looks thin though.

You can have inaudible light detonation that is slowly hammering away at your internals that only a knock sensor will pickup. You can also have total preignition that is blowing stuff apart due to the extreme force. This is why modern ECU's have knock sensors and retract timing. Sometimes you can't pull enough timing and bad gas is that, you end up with something like this. it's not black/white on/off there is inbetween with it.

I laugh again that there is someone who thinks because an air cooled once detonated, and they backed off that there is no way detonation can cause damage. That is mind blowingly stupid.

Any of you are welcome to come play where I do & show me how much smarter you are than I. I'm reading a lot of words like "hate", "stupid", & "asshole"....the ass kissing smile was nice also. Too bad you clowns can't carry on a discussion without resorting to personal attacks.

The fact is that my engine did pre-ignite. Nothing broke and when I tore it down 7 years later, the piston tops, ring lands, rods & bearings showed no damage from that brief incident. Why piston tops you might ask?... because that is where detonation shows up most obviously. Rods can be bent from a few other causes and your pics show pistons in decent shape......they are whole for one and the tops aren't shown.

Here's a pic of the piston tops as removed from my engine....another after clean up. Nothing as trick as your T-4 pistons, but it was all I had. I noted that Robbie didn't show the tops of the pistons that survived his contretemps. His deduction that everything else is fine is simplistic....cause it ain't. There is crap all thru the oiling system.....but hay, what does a dummy like me know. Ya better ask Jake.

You laugh because ignorance is bliss it would seem.

Detonation's effect on a piston....*warning* not for the women & kiddies.

This will probably come as a big surprise, but high performance engines have been tuned to run at light knock for years

Why? It's where the max power point is.

Harry Ricardo noted this in the 1920's....

When you minimize engine part strength to minimize reciprocating part weight (ricer engines), you have to pay way more attention to the knock. Knock sensors were designed to run those engine at the hairy point of knock and to back it off slightly.

That being said, seen any 30 year old Honduh engines lately???

No? It's because they all went boom and there ain't any left......

Aircoolds are a bit more succeptable to knock because they run hotter.

Ugly melt on that piston JP

They also run on the ragged edge of lean for fuel economy. Without knock sensors they wouldn't last thru the warranty period.

I suppose the rest of you knew what contretemps means too.


Blowing a motor is costly and embarassing for a minute. What you learn from it is invaluable if you apply it in the future. I'm not to proud to say I smoked a few. I am proud to say I never smoked two the same way.

So far, I'm good on vective, specious and contretemps. I've got a Webster's handy just in case though.

Personally, I think it was PU's fault.

The only things that will be reused from the old engine are the crank, heads... The external oil lines are being replaced too. The case, rods, pistons, etc. will be new. Everything will be meticulously cleaned. I am not concerned about the "oiling system". Which part of the oiling system are you concerned with? I'm not calling you a dummy but hey? What is left after you replace all that? The heads will be cleaned and refreshed, the crank will be cleaned... What system? Are you imagining some elaborate system? Nope. Just a remote filter with a line in and out.

90% + of these cars are Type IV motors. If you don't want to be called names then don't start this 6 vs. 4 crap. You're outnumbered and frankly your argument is tired. If you see a thread on the Type IV motor just move along.

Quit inviting people to come play in your playground too... Your not fast, your car isn't that fast either. Britain would be fast in an '80 Cavalier with bald junkyard tires... That glory isn't yours, quit claiming it.

Back on the gas... Yesterday I dropped the BMW off at the dealership for a check. It just had the major service interval in May and I have put about 1300 miles on since. It was killing at stop light/signs so I asked them to look it over to see if something was incorrectly adjusted at the service interval. Yopu dropped me off this morning and the service manager told me to come on back, he had my fuel filter skinned open and it was full of water and gum. It was replaced at the service. Yup. You guessed it, it got some of that gas too. Road it around Lake Tahoe this afternoon and got home an hour ago. Ran like a top with the new fuel filter.

Fortunately you don't make the rules.

I did build every bit of my car so I should get a few of the bragging rights. You checkbook "builders" haven't a clue as to what that involves. The car & Brit were fast enough to lay it on every 914 at the Shoot Out in Ca last year. I notice you weren't there. When you get to be my age 2 seconds off his pace is about all one can expect.......still fast enough to whip you like a dog in the street,..no great accomplishment there.

Since you are being an asshole, I'll feel free to say that one would have to have less mechanical sympathy than a 3rd world goat herder to let bad gas destroy an engine. Write another check, chump.

My work here is done.

I didn't write a check. I built it. And you forget. I have seen you and your car. You got nothin'. Beaten by one of those Type IV's you love to bag on. By more than 2 seconds too if I recall correctly.

I wasn't at the shootout because I was OMG! building my car! Not writing checks. Underneath it building the suspension! Guess that argument was weak too huh?

I'm not being an asshole as you put it. I am simply telling you not to be one. You have nothing to contribute to this discussion. Leave it alone.

What makes you think that a herder (often called musterer) would have a lower IQ , or mechanical ability than someone of your age and experience?

Think of all the potential broken down tractors, tanks, humvees, and personel careerers that this herder may have encountered during the course of his lifetime...and possibly revived to make run once again so that he could sell them off to enhance the size of his herd.

Talk about bad gas...I would suspect that the accused herder would have some serious purity issues with the fuel supply in his country, potentially some mixed octane of unknown origins...

So, I would suggest that a herder or goat, sheep or even swine may have considerable experience with bad fuel, unknown mechanical issues, and custom parts replacement....far greater than any of our experience may possibly add up to when we walk into a parts store to order the exact replacement part we need, pass by the gas station and go in to get fuel and milk...milk that may have possibly come from a goat of foreign origin....managed by a herder.

Rich

Whats wrong with a personal attack?? Is their any other type?? If an attack doesn't hit home and piss someone off, then why make it??? Right JP?

For the better part of two years I have gone above and beyond to hold my temper with a few people, just because I don't have the time to deal with "it"... But there comes a time when I really don't give a damn and that time has come.

Glad to hear that you built your car JP, because there is no way anyone else could please you.. and why don't you buy a tail dragger to put that engine in, so you can fit in with the rest of the crowd that shares your attitude.

You've built one car... I built a dozen before I was 18 years old, by myself in an old shop on top of a Mountain in Georgia...

One day we'll meet and I'll ensure that you won't know when or where and it may be sooner than you think.

My work has been attacked by JP for the better part of this Millennium. I value this work as much as any family member...

Speaking of bad gas... Today we tore into a 996, 3.6 Vario Cam + engine that had cylinder liner failure.. It seems that the fuel in RUSSIA has attacked the cylinder liners and delaminated them with only 30K on the engine... Fuel can impact lots of aspects of an engine.. Just look at BMW with the Alusil issues of the past, attributed to the US fuel blend..

Ever had someone ship you an engine from Russia, JP???

yah....but can you herd goats??

I never mentioned IQ. I know a few guys that have an IQ slightly higher than an eggplant who have a marvelous feel for things mechanical....yourself, for instance.

ah IC you are in rare form tonight.

Eggplants can come in so many sizes...therefore many levels of IQ, if it can even be measured with common measurement methodologies.

Just because you think that an Eggplant has an IQ lower than yours....does that mean it truely does?
Remember people used to think the world was flat also...

Diffusing is an art form.

Rich

Wow, seems like a lot of history here. For us newbies who are just getting to know each other, can I (we) get a little background on who's who? Seems like the primary players are JP and Jake, and of course Robby who started it all. So, who's who?

How long have you been playing with 914s?

Appx # of (re)builds (any)?
Appx # of (re)builds (type 4)?

Appx year of first engine (re)build (any)?
Appx year of first (re)build (type 4)?

Appx year of last engine (re)build (any)?
Appx year of last (re)build (type 4)?

Any special achievements (high MPG, high HP, high TQ, Longevity, Race Results, etc)?

Cars currently owned?

Others feel free to answer and / or add questions.

This could get interesting

Pot, meet Mr. Kettle.

The drama in this thread is BS, but I will chime in to say that Rob built his own car. I would know since I've seen it from pretty much start to finish.

No, sorry you cant ask those questions here.
Its against all the truely rational behaviour we hold dear.
No pot stirring allowed.

Rich

You inched ahead of a stock 2.0 ( at that time ) powered car with an open diff ( at that time ) and the wrong tires the first day, and then lost the second day when we put some DOT tires on the car.

We need to have another one of these events next year so you can see how well you can lay it on us with double the power and a limited slip...

Oh and this time you need to remember that it's against the rules down here to have a geezer warming the tires for their hotshoe driver in the same rungroup.

It's all in good fun though, but when you start boasting about winning by a tenth on your own averaged combination of times as "laying it on us" you might want to check on your facts.

BTW I'm serious about having another shootout, that was pretty fun...

We are having another but up in the Southern portion of Washington on August 8th and 9th. You should come Chris.

JP... leave it alone...Rob is a very nice guy who has done a lot for people wo really didn't deserve it. Shit happens but there really doesn't need to be a pissing match between an old guy and and an over confident arogant engine builder. You both are 914 guys and the car brings us all together. In person I am sure we would allBS and laugh about this.

I like 6 cylinders. I don't bag on the 6 guys... I just think that for once that crap should be left out...

Wow had this strayed from its origins... I hadn't read it for awhile, and whoa- what was the topic... oh, yeah, a broken motor and crappy gas.

Still think this sucks for ConeDodger, but with the issues with other gas appliances around his place, seems build quality, or parts quality are not the problem here.

4 vs 6. Not again. The 4 guys like the light weight, and "underdog" status of the motors, the 6 guys have the heritage thing going on. I suppose now someone is going to chime in that you can't turbo a 914 either. (I'll be posting some pics to my build thread soon). What type of car has won the last several Porsche parade autocrosses? That'd be a 914. 4 cyl. Have there been some 6 cyl wins? You betcha.

Lets just all be friends, 4 vs 6 will never be resolved. Agree to dis-agree?

And support our 914 friend, ConeDodger on his replacement motor. If he wasn't 1/2 a country away, I'd invite him over to help me build my next motor. Being built not because it is a 4 cyl and it blew up, (it didn't) but being built because it can be so much more than it is, I like the idea of a lightweight 914, and I like to play around in the garage.

Rob, anyone,
Is there any legal recourse that can be taken for these instances of bad gas? Any way to tell sooner than a blown engine that you have just gotten some of the bad gas?
By the way Rob, sorry to hear of your misfortune, hope you build an even better engine this time.
Tom

Jake would have known because of all the instrumentation he puts on his engines when he puts them on the dyno. The one gauge that would probably have been doing something odd (correct me if I am wrong Jake) is the EGT which I do have. I typically don't watch this gauge as it is up on the A-Pillar and really only relevent at WOT. I was on the freeway at steady state speed in 3 or 4 gear. I only sample CHT off of number 3 and it was fine. But what do I know? I'm just a goat herder with a PhD...

I have no time for lawyers. I doubt the gas station is liable beyond the fill I put in. In other words, I hire a lawyer to get another tank of gas.

It will be bigger and badder...

it depends. You blow your motor a half block from the station, behind another guy who just blew his engine - you can make a pretty strong case (take fuel samples, go back to the pump and get some from there too...) You put all your spare gas in a big container and draw out what you need now and then? Good luck pointing the finger at any one supplier...
Like Jake says - it'll show up on EGT instantly if it's an octane problem. (If it's water the engine will probably just die, drain it, refill it, be on your way.) However, most of us without dynos, airplanes, or race cars, don't have EGT meters installed... Maybe it's becoming the price to pay for trying to run an air cooled engine these days. This thread has had me thinking even more seriously about adding one to my next car/engine/exhaust build...

Wow PETA must be making some serious headway if you need a PhD for herding sheep. But what about

I was talking to a PhD the other day at my front door. He wouldn't leave until I paid for the Pizza.

PhD - Pizzahut Delivery.

I guess if you didn't spend any money to build it the first time, and your not spending a dime for the Rebuild, maybe we should keep our opions to ourselves.

Bigger and Badder??? 3.0 Flat FOUR????

4 vs. 6? I have one of each and LOVE them both.

Mind you, when I park them beside each other in the garage overnight, in the morning there's stuff knocked off shelves, cans on the floor, maybe a bent wiper blade or a busted mirror. Once the six had naughty German words sprayed down it's side in oil



I have no doubt that between you and Jake it'll be better than ever!

I'm right there with you. I was dreaming up mounting the four gauges in my center console. A single EGT gauge wouldn't do it. It would be an average of all 4. I also run an AFR, but again it's an average. I'm thinking the best bang for the buck is to pay for the dyno tune. I do have to say that once I get my carb jetting dialed in I don't pay much attention to the AFR unless the engine runs rough. Oil temp, head temp and pressure are a different story. I check those as often as I check my mirrors.

I don't like that idea because you don't care about majority rule, you care about the one cylinder with the BIG problem. e.g. - one dead cylinder may bring the average down a bit which you may not notice. 3 at 600 and one at room temperature will get your attention... Blow-torch high EGT's from bad gas _should_ be across-the-board, but even if only cylinder were peaking for some reason you'd want to know, as we've seen. The piston exiting the case is the problem and you can take no solace from the n-1 remaining good ones...

If you've got the bucks (and when we're talking about the cost of some of these engines it falls into the 'cheap insurance' category...) like the aircraft guys do, there are nice combo gauges that tell all. Do a search or go to Aircraft Spruce and have a look for "GEM" -- Graphical Engine Monitor. Shows CHT and EGT on a single multiple-bar-graph display. Since those guys are constantly monitoring fuel trims to achieve (something like) 50ºF lean-of-peak in cruise, it's really nice.

I think you could get by easily with one AFR sensor per collector but you really need one CHT and EGT per cylinder. Finding a way to package the display for convenient dashboard presentation is a little challenge, but I think with a cheap 8051 microcontroller and an LCD display or some 10-segment LED bar graphs you'd have enough data to keep you out of the danger zone.

4 channel, single readout, scanning EGT - advances at one second intervals.
Available exclusively at Tangerine Racing Products!

Chris,
My eyes are not getting better as I get older....and with the sunshine of the open top car, I would prefer analog....but...
Are the led panels red, or black/clear?
I cant see the black letter ones, but the red ones shine better in the sun.

rich

Yeah, thats why I was thinking of four gauges. One per cylinder. I like analog also. One quick look is all it takes. I'm persnickety too. All the gauges need to match.