Engine Durability Tests
 

The issue of engine durability testing came up on a couple of recent new marine engine announcement threads. I like to keep a low profile with regards to my work background, but in this case it is pertinent. For several years I worked as a test engineer for an automotive OEM, and did engine durability tests, along with other components. There was some interest from people in the threads on what tests we ran. Wildman_grapfix suggested I start a new thread so here it is.

Some of the engine tests we ran:

* 100 hours full throttle between peak torque and peak horsepower. Some tests were extended to 200 hours. Now I believe 200 is the norm. They run some to 400 hours.
* Long term idle tests (sounds easy, but is brutal on some parts, especially the old flat tappet cams).
* Cold start tests to -20F or below.
* Overheating tests, including running engine with no coolant. Especially hard on head gaskets, and piston scuffing.
* Road tests up to 100,000 miles, and some at high speeds up to 100 mph.
* Octane tests.
* Water ingestion and splash tests (run the car through deep water at high speeds)
* Cooling tests (idle, grade, towing).
* Coolant corrosion tests.
* Fleet tests.
* Salt spray tests for part corrosion and electronics sealing.

The testing is very extensive, and is one reason why automobile engines last so long now. I was talking to some Ford engineers last Fall, and was impressed with the testing they did on their Ecoboost engine. They said they did their durability test at full throttle at peak horsepower for I believe 200 hours. That's brutal for a turbo engine! One engine they ran in the Baja 1000 race, put it through some towing tests, and then put it through their normal dyno durability schedule. On their Powerstroke diesel engine, they essentially double the gasoline test schedule.

I forgot to mention that the auto manufacturers do so much engine dyno durability testing that they actually sell the power generated by the testing back to the utility companies.

I would love to hear what the durability tests consist of for marine engine manufacturers. I know Mercury marine has dyno facilities, and on the water testing facilities. I couldn't get any specifics from the sales person for Mercury, however.

Michael

Would be very cool to know.

Thank for posting, I worked for a company that supplied the OEM's.

Pretty hard for aftermarket to test like the OEM's require.

Question,

On the Max tests, what load is on the motor?

Engine throttle is wide open, and engine speed is determined by the computer controlled load of the electric dyno.

Michael

I highly doubt you will get any "official" numbers. Should be a good thread to follow though.

Wow!
 

I'm more of an O/B guy but follow all things internal combustion and those tests are brutal! I've been building my own O/B's for the last 35 yrs and have done some pretty strong ones in the last 7 or 8 yrs but NONE of them would live through that!
I know in my world too I've been through the vendors selling me parts based on "facts" and actual "data" that were in reality hypothetical.
I spend a great deal of time/effort on idle quality with mine and it's way harder to do than most know. Many can build a hot rod motor now make it idle let alone live.

Great thread and thanks for writing it. I can't remember the last marine based endurance test I saw. Closest I'm thinking is maybe Pleasure Craft and Indmar but nothing into the Performance levels talked about on this board. Most #'s posted here baffle me if real ;)

Michael1, you may get some general information from the marine engine manufacturers, but I would not expect much detail.

I have been a design engineer for a component supplier in the HVAC&R industry for 20 years and now engineering manager for new product development. We have developed many variations of accelerated life tests in attempt to simulate 15+ years of actual use to verify new product designs. Many of these tests are considered highly confidential. No sense in announcing to your competitors new and better ways to test new products.

That being said, I still believe the ultimate product validation is time in 'actual' field use. While we work very hard to simulate and accelerate results in a lab environment, there is always the potential for a combination of variables to exist in actual field use that one does not expect. Almost all of the root causes to field problems I have had to deal with over the years were due to multiple variables occuring in combination. Although, information from actual field experience sure does help develop new accelerated life tests for the lab! Hence, the confidential nature on this subject.

"Economy of Scale"
 

I certainly understand your interest in these kinds of tests and data but I must say that for most all marine performance engine manufacturers except possibly Mercury Marine this is pretty much strictly a cost factor issue.
First, the type of dynometers for this type of testing have to be very large eddy current type of dynos with very elaborate test cells and data monitoring hookup and recording systems. This is not to mention the multiple dyno cell facilites needed by a manufacturer to allow other dyno testing and calibration to go on dailey as needed while lets say 8-10 day continous operation dyno load tests are conducted.
Most marine performance engine builders only have maybe one or two smaller water brake type dynometers with no real extended capacity for these types of continuous duty engine load tests.
When one such as yourself with large OEM manufacturer test expierences tries to apply these same procedures to the very small limited marine performance engine market it's not in my opinion a viable comparison as the "Economy of Scale" is not there.
The large engine manufacturing firms that have these multi-million dollar test facilities it is cost effective in that they are designing, engineering and testing engines that will go in hundreds of theousands and in some cases millions of vehicles.
I would suspect even the largest marine performance engine manufactuers, even Mercury Marine who is probably building only thousands of engines per year at a MAX or a smaller specialty firm like Ilmor who is probably doing well when they build and ship a thousand engines a year, there is not going to be an "Economy of Scale " for such a huge investment and costly undertaking for the engine sale and distribution the costs would have to be spread over.
What most quality marine engine performance builders do is to use years of experience, limited dyno testing, in the water testing, warranty claims problems, racing experience and actual customer usage to help develop engine design platforms that will deliver and demonstrate the reliability and performance their markets demand and accept.
These same quality product builders will also use the best aftermarket parts and engineering they can secure for these new engines and still supply the product in a fairly resonable cost range for the end user.
I know you expressed the thought that our small market marine performance engines are way to over priced when one compares them to what "Detroit" for example develops and provides. Well when you again consider that almost all engines deveopled in the big automaker markets especially performance engines and crate engines are built and sold in the hundreds of thousands and millions again the cost comparison is almost a mute point. I am sure a GM engine plant such as Tonawanda or others for examples , assembles and produces more engines in one day or week than the entire marine engine producers do in an entire year. Again, "Economy of Scale"
If you with your OEM testing knowledge and expierence and you current expertise as a consultant can come up with a way for small manufacturers to build these type of test labs and avail themselves with this kind of elaborate test formats and do it in a way that will tranlate back into the engines at or near the same scale as that afforded to big OEM manufacturers then I am sure I as well as them will be all ears, minds open and very excited about using and providing more of this type of elaborate testing and improved resultant product.
JMO

Best Regards,
Ray @ Raylar

I have had the tour at Ilmor's facility in Plymouth MI and saw multiple dyno cells. There are other facilities around Detroit doing work for the big manufacturers, who could probably do this testing under contract for engine builders not equipped to do their own. It's not just the cost of renting a dyno and technician for a week, think about the cost of fuel for 100 hours @ WOT on a 750 HP engine!

750 HP X .5 lb/hr X 100 hours X 1/6 X $4.00/gal = $25,000.00

Tomcat:

That was kinda my point, "Economy of Scale" spend $25K +++++ to test one $$25Kto $50K engine, I don't think so.:ernaehrung004:

Best Regards,
Ray @ Raylar

I'm a test engineer. My building has 100 dyno cells, we don't sell the power back to the grid, it's too cyclical. We could probably make tons of it though, since we build huge diesels! It just gets dumped into a heat sink unfortunately. One of my coworkers used to work for mercury marine, he's described some of their test procedures to me. Apparently they like to let interns loose with the boats a lot lol. Sounds like a great job to me.

You got one thing right, it takes cubic dollars to run world class engine testing facility. An army of engineers with masters degrees and Phds from the best schools in the world, lots of mechanics, butt loads of very expensive instrumentation, fancy software with expensive licenses etc.

These costs are passed on to the companies that buy our equipment, and then to you the consumer. The EPA is essentially enforcing taxation that will be born by nearly every product you buy or use, since virtually everything will either be hauled or built by a diesel engine. I'll step down off my Ron Paul soapbox now.

Yeah, you're right Ray. Throw in some CARB emission testing while you're at it. You would have to believe that you were going to sell a lot of copies of the engine, and amortize the cost over that volume. You would also have to believe that the engine could actually pass the test, otherwise you can add the cost of failed engines to the bill.

Good point.
 

I remember reading when GM decided to drop the 454 that Mercruiser went to Detroit to try and change their minds.
I don't remember the math but I'm thinking it was one weeks production equaled Mercs anual total volume sold :helmet:

And you guys are right about the on water testing too. OMC/BRP and Merc do tons. Merc used to have three yellow 22' Velocity O/B's I used to see following each other around all the time. They also have docks w/motor boards on for the O/B's. Fill em w/gas, pin the throttles and go home.
I think they do similar w/the I/O's.

CMI really sets the standard for durability, everyone should look to them as an example.....

Katech does some 24hr plus equivalent durability testing.

Jeff

Into a heat sink? I hope it's inside the HVAC system so you can at least heat the buildings. :D That's a lot of dyno cells.

Michael

Ray,

Thank you for your perspective. I think there is merit to what you say. Amortizing durability test costs over a small production run will increase unit costs. Now if someone could convince CARB and the EPA, we would be all set.

Michael

Convince CARB and EPA, hell, lets just get rid of them!

Best Regards,
Ray @ Raylar

Exactly, These UN-elected Draconian agencies need to go; there are a bunch of them.

Get this, CARB spends $0.6 Billion a year dreaming up new smog laws, and paying people with fake degrees (yes, that has actually happened, and the guy still works there fabricating global warming numbers).

Michael