I got asked this the other day on phone by a potential new race engine customer, I thought it was good question to pass to the other end of the gammit, the engine customer. This fella had a engine built by reputable builder, he race it a handful of races, then it broke, connecting rod/crankshaft failure of some sort, he has yet to get it disassembled and fully determined what the failure is as of yet, the guy wanted to believe it was the builder's fault and ask me what I thought.

Here's my thought, Dave and I have discussed this on the phone before, if the builder missed some critical issue, bearing clearence, left a something loose, whatever, then whatever failure that would occur, would do so real early, probably in the first session on track. I know I always like to hear my customer has gotten thru the firsr session without issue, from that point on I can breath easier. if the engine last a few races, I dont realy care if it was 1, 5 or 10 race weekends, then if the engine fialed, some part failed, plain and simple, and all sort of parts can fail, whether it be Carrillo rods, a billet crank, they all can fail under race conditions. I told the customer, if it was the builder's fault, then it would have happen sooner, so no it's not the builder's fault in my opinion. I know this to be true, because I understand this work, but maybe not all customers do understand this.

So there lies my question, what do you think?

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Hap Waldrop
MGexperience Supporting Vendor
Make Sure to check our promotions/product offerings in the Vendor Deals Forum here.



Edited 1 time(s). Last edit at 02/07/2012 06:57PM by Speedracer.

Hap, I'm relatively new to this forum and have been reading with great interest posts by all the members here on everything imaginable on the MG.
In a past life I owned a Marine dealership that specialized in Mercury Outboards and all the major brands SternDrive I/O's. Not only was I the owner but I was also chief cook and bottle washer and built many two and four stroke engines in my 18 years in business. I had Marine Tech schooling from both Mercury and OMC in order to do warranty work. With all this being said I was always happy to hear from my customers that the "fresh" rebuild made it thru a weekend on the water and like you I always felt an error in assembly or judgement would show its ugly face very quick. For what it's worth, I ran all my builds on a Dyno before the owner got it back but I still wasn't at ease untill the weekend report came thru. After that if a problem did show up it pretty well had to be a "part" failure.
Again, I'm enjoying all the info I receive from this forum.

Joel

Good question.

What if one of those parts had a nick or a ding (shipping damage) that led to the formation of a crack, and the engine builder missed it or chose to ignore it? Or what if the engine builder performed some machining on one of those parts, and a crack initiates where he left a sharp radius? In my mind, the engine builder should take some responsibility in both of these cases.

But to your point, if a Carillo rod is installed, and there was nothing (short of x-ray, FPI, MPI) that would have indicated the part was flawed or going to fail, then it's not the engine builder's fault.

A professional failure analysis can usually answer these questions....unfortunately, the going rate is about $10k



Edited 2 time(s). Last edit at 02/07/2012 07:42PM by Benny.

One should never forget that every part of a race engine is constantly seeking daylight.

It's hard to warranty something like a race engine. Lots of engine stresses at speed, driver's see red mist and over rev the thing, who knows ... sacrifices must be made to the gods of speed at some point.

I'd agree that a build error will show itself very early. Otherwise it comes with the territory.

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2012 SCCA FP MARRS Champion

Fred makes good points, all of these parts are doing their best to self-destruct. The fact that they stay together for more than one weekend should make us all happy. I've had my share of part failures, and some on the very first day of test and tune. Makes for a miserable weekend and a long pull home.

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If I can't be fast, I'll just be obnoxious!

If it survives the dyno session and tuning before it ships to the customer it's good. If a builder doesn't put it on the dyno, they're on the hook for some shake-down time. How long should be agreed before the engine is built.

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Basil C. Adams
1956 MGA Coupe (Show Car)
1957 MGA Roadster (Driver)
1958 MGA Coupe (Racecar)
1959 MGA Coupe (unrestored)
1960 MGA Coupe (unrestored)
1960 MGA Roadster (Driver)
MKIII Elva Courier (E1056)
1967 427 Cobra
1972 Alfa Romeo Montreal
A coupla late MGBs
1960 Austin Healy BN7
More Cars than Brains

When is it the engine builders fault?


When you build your own race engines...

Dick

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Errabundi Saepe, Semper Certi
(Often wrong, but always certain)

Yes , and no, Dick I know you build your own, and obviously so do I, and if the one I built for Fred, now belonging to me, in the car right now, had a failure, that I couldn't explain, say as for the gauges, no temp, or pressure issue seen at the gauges, then I have to get inside and probably write as some sort of part failure, due to the point, it's ran so well now for 3 outings.

I think as builder, I also worry about the guy using the motor, as well as myself, he could botch the timing, or fuel mixture to a point that could cause a failure, more than likely it would show up as a burned piston and be repairable, but it could also be water overheating, due to bad cooling design on the car, way off on the ignition timing and that could result in a nasty failure. I recently bought a box of 240 degree pop tabs, you attach them to the cylinder head, if the engine ever reached 240 degrees (overheated) the pop tab would pop, and tell me that the engine had overheated.

Benny I see your point, that type of scenerio would most likely show on a crankshaft, it seems some crank grinders don't do great filet radiuses at the journal, I'm fortunate to have a great crank grinder, but I've seen crank break or cracked that had perfect radiuses as well, even factory std./std cranks, it's rare, but I've seen it, and more than once.

The only engine I ever had someone else ever build for me, (a SCCA full prep 1275) at the time I had a great sales job at the time, and was making plenty of money, just forked over the cash and let him do it for me, a very good friend, still is, anyway it broke a crank 5 races weekend in, I never got riled about it, I knew it had ran too well and too long to be a build problem, I wrote it as oh well, cranks will break when you turn them over 8000 rpm. On tear down and inspection, the crank had broke at the front of the center main journal, right at the radius , which was nice radius I might add, but it still borke there, I didn't see anyhting that I thought could have been done better, or was not done properly, it just broke.

I've never seen a MGB crank broken, I'm sure it happens, I've just never seen it, I'm sure if I do this long enough I will. With race 1275s I seen lot of folks break cranks, even Moldex billet crnaks, I always contributed this to the 3 main design and what guys were doing with them. The guy I seen break the Moldex billet in the 1275, he's always been one of the fastst FP racers on SCCA national level, and past national champion, he also told me he turned the engine consistently over 9000 rpms, so I guess if you play that game, you're going to break some good parts, sooner or later. I think most vintage racers are much more conservative on rpm, I know I turning my engine less than it can turn for example, it's not like I racing for big money, fame or fortune

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Hap Waldrop
MGexperience Supporting Vendor
Make Sure to check our promotions/product offerings in the Vendor Deals Forum here.

As I am sorta retired, it's been a while........

But every time I rebuild a engine, even if just stock, I am NERVOUS.


Might be because I have made mistakes..........

But so much cannot be seen in the best of circumstances.

Interesting comments about breaking cranks. I recently had a new customer first come to me after he broke a crank in his MGB race engine. This engine had a number of years of racing on it and also some street miles. He sent me his salvageable parts to use in a new build/rebuild. I didn't get to see his block or broken crank. Based on inspection of his head this was a nearly stock, albeit large bore engine. The point to all this is, in racing, due to many factors, anything can fail. His new engine will have a heat treated crank.

As far as builder liability for customer engine failures, any builder who has repeated/frequent failures in the field won't be in business doing this for long. OTOH, any builder who builds numerous engines will see an occasional field failure. This due to a number of reasons, many of which are beyond the builder's control. Things such as mistakes made during installation, wrong timing, bad fuel, wrong jetting etc. If I get to tear down someones failed engine for analysis, it will often be apparent as to what caused the failure, but not always. In my previous life in the engine design and development business at GM, I probably inspected over 1000 torn down engines. Since many of these were deliberatly tested to failure, I have a lot of experience analyzing the cause.

As to Basil's comment about dyno testing, if you need this to test your work you'll be generating lots of scrap and the price of your engines will be a lot higher. I much prefer to verify all aspects of the engine as I build it. In most cases, trying to inspect quality into a product is futile at best. AFAIK, I've never shipped an engine to a customer that didn't start and run well as received, this without any dyno testing. For me, trying to do jetting on a dyno here in Colo. at 6500 ft elevation for users running near sea level would be non-productive.

It is, of course, the builders responsibility to know that machine work is done correctly, part specifications are correct and compatible and that purchased parts are of good quality. Things such as rod bolts and valve springs for example can be visually inspected for surface defects but you are at the mercy of the supplier when it comes to hidden flaws such as steel inclusions, wrong heat treat etc. As Hap says, waiting to hear back from the customer after the first outing can be the most trying aspect of building race engines for customers.



Edited 1 time(s). Last edit at 02/08/2012 09:25AM by fast-MG.com.

Race engines are way overstressed to start with.
The fact that NASCAR and FIA engines frequently fail 'in practice' and have to be replaced is evidence that sometimes things go wrong despite a builder's best efforts and the quality of the parts.

These A and B engines are also very old. The remarkable thing about them is how stout they are and forgiving of things like over reving. I've only had one engine (a 948) lose the bottom end. That was due to a leaking front seal draining all the oil out of the sump, not the pump or bearings. Even at that, though it sounded like the hammers of hell, the rods and crank did not break and the engine never seized. If something goes awry on a rebuild, it will happen immediately. The engine won't run great for a race or two then die.

Builders race on their reputation, but once a motor reved in anger... then the owner is truely 'on his own'.

What are the warrenties that any of the Big Time race motor builders? No doubt if you called Gibbs, Yates, Pink, Reher-Morrison and asked them about their warranty policies... you'd get laughed off the phone!

Hap, this sounds very much like the conversation we had last night, while doing a post mortem on my latest engine failure.

(No, kiddies, Hap didn't build the engine, I did. I just picked his brain, bought his and Dave's parts and did my thing. )

As for "warranties" on race motors, I'm reminded of the statement made to me when I bought my first car, as a teeny-bopper. "You get a 50-50 guarantee - That is, if it breaks in half on the way home, you get to keep both pieces".

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Rick

You might be a racer if;
You consider the redline as a "conservative suggestion" and the rev limiter a "fun limiter".

Good line, Rick...

Would you be willing to share with us the nature of your engine failure and results of the autopsy?

Dick

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Errabundi Saepe, Semper Certi
(Often wrong, but always certain)

I've been on both sides of this. I've dealt with incompetent engine builders who have made stupid mistakes, and I have dealt with (more) customers who have grenaded their engines and are looking for someone to blame.

I had one engine builder as a client that called me to look at the remains of an engine that a customer was claiming had been defective. I pointed out that when all of the pistons had the imprint of the valves on them and my guy had checked static clearance at full lift, the customer had obviously over revved the engine resulting in things hitting other bits. End of case.

I have also explained to people that I have helped assemble engines , or advised on doing so (I seem to get a lot of Twin Cam owners asking questions) that any mechanical device is guaranteed to fail if you you use it long enough, and that there is no way of knowing just how much of the fatigue life of any given component has already been used up. When you use a crank or rods out of a used engine, you take precautions and magnaflux or otherwise crack test them, but if an existing crack hasn't reached the surface or if it simply cracks right after it is placed in service, that's the way it goes.

I had one guy with a TR-3 that refused to believe me when I told him that the beefy 3 main crank would last indefinitely at 5500, a season or three at 6000, and probably a race or two at 6500 or more. He saw the TR-4s running 7500 and 14:1 compression and figured he should be able to do that as well. He has at least 2 or 3 doorstops now in the shape of half crankshafts.

Given that an engine failure often destroys much of the evidence of how it was assembled, it is hard to support a valid claim against a builder unless there is an obvious boneheaded mistake - flywheel bolts missing, grade 5 bolt sused in con rods or something like that.

The practical problem is that the guy that blew the engine is going to go around bad mouthing the builder even it the thing blew because ran it too high or without enough oil, or whatever, so as a PR proposition, being a racing engine builder can suck a bit. While I build my own, I sure wouldn't want to do it for a living - and if I did, I'd probably tell the customers there was zero warranty unless they ran a rev limiter and could show that there was some mistake in assembly.

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Bill Spohn www.rhodo.citymax.com/carstuff.html
1958 MGA Twincam (race car), 1962 MGA Deluxe Coupe
1969 MGC roadster, 1957 Jamaican MGA
1965 Jensen CV8, 1971 Jensen Interceptor
1969 Lamborghini Islero S, 1988 Fiero GT turbo
2009 Pontiac Solstice GXP Coupe
West Vancouver BC

Rick, not you, this has nothing to do with your engine. Just so the folks here know what's going on. Rick assembles his own engines, both Dave and I have done some component work for Rick, and sold him parts. At Roeblign Road race back in Dec. Rick lost oil pressure, and shut the engine down, the culprit seem to be either the oil pump or oil pump drive, we've seen the drive, it's a bronze drive, and i'ts got the gears chewed off of it, so next move is pull the oil pump apart and see it fialed inside or not, at first I thought along the lines of that gear failed, but Dave told me to check the pump, because that might be the failure, so Rick is going to bring the oil pump back here and we take it apart and look at, if the pump failed causing the bronze gear to fail on the drive pump, then it probably was a savior to camshaft, because the gears on the cam arere in perfect shape, if that had been a stock steel gear, the cam would be toast as well. Dave told me he had seen a few oil pump come aaprt where the star gear attaches to the drive pin, the tow pices are held together with a pin, if that pin moves, or loosen up it can come ut enough to lock the pump down. So we look at the oil pump next and see if we can fiquire out what made the gear fail.


Either way, it's weird failure, and I've never seen before.


Dave you might be glad you never messed with A series, broken cranks are a way of life with the way those things, and people pushing those thing alot hard than B series engine. I liked racing Spridgets, they are alot of fun, but I enjoy the MGB as well, it's faster down the straight, and bit more reliable, but a tad harder to work on thasn a Spridget. overall I enjoying the change from the Spridgets to the MGBs.

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Hap Waldrop
MGexperience Supporting Vendor
Make Sure to check our promotions/product offerings in the Vendor Deals Forum here.

Hap pretty much covered it. As soon as I can get the pump to him, maybe we'll know with some certainty what was the initial cause. And thus how to avoid it the future. Hopefully I'll learn something here. Even if it is nothing more than to check the pin in the pump next time!

As for me, I am in total agreement with most of the posts here; if an engine (or transmission, or diff.) fails after the 2 or 3 or 10th weekend, it ain't the builders fault. It's most likely a component failure, at that point.

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Rick

You might be a racer if;
You consider the redline as a "conservative suggestion" and the rev limiter a "fun limiter".

I agree with Hap's original premise - if it lasts awhile there's no way to assign "blame"

i build my own, but depend on various experts to provide, machine and or fit certain parts for me

in the last 2 months i've posted lots of build questions here - becuz - a supplier clearly misfit a part that i had to farm out for work - the engine destructed in under 100 miles - (his fault "damn right"

my fault, as the final assembler

mea culpa - - i still personally bear the responsibility to double check everything as best as possible - i didn't double check his work - i trusted that supplier -

costly lessons - (i have more parts from this guy - but i will never be confident to use them)

i wanted to get it right this time

- this forum has provided many important lessons & solid advice

- and i think i now have an engine that will live on the track (within the confines of my build budget and sensible driving technique)

but as mentioned above - anything can fail - at anytime -

unless one starts with all new performance intended and prepped parts - one never knows what may happen by the luck of the draw,

or becuz of driver technique when the fever strikes out there on the track

-



Edited 1 time(s). Last edit at 02/09/2012 12:30PM by larrym.

I've had several engine failures, all my fault.
Be sure to replace the rear crank seal.....With a quality product
Be sure to use a quality oil filter....... [fell off]
Make sure your machinist understands brass valve guides need more clearance.
Make sure oil cooler lines do NOT go up too high. [VW-engined formula car]

Agreed.

In racing, you gotta remember you are pushing the envelope.

On the street, you can stagger along with a really shoddy rebuild a long time before things come apart.

Since I have always done my own engines (short of machine work) I have no one to blame but myself. My one failure (so far) was my very first engine build (VW air-cooled) and I re-used things I shouldn't have... lasted a couple thousand miles before it tossed a rod.

So, one race session or hot practise would seem to me to be reasonable, unless you KNOW the hot-foot did something, er, "unkind" to the engine.