Engine designs that have problems 22

[enginesrus]

Since the one thread I started, is headed way off topic, reason for this.
Engine designs that have problems or have had them.
I'll start with the 3 valve Triton.
This guy explains. Has data from others that deal with the same problems.

https://www.youtube.com/watch?v=xcN_WcGr4BU

 

[enginesrus]

I don't know of many mechanical items that use chains that have a long life time. And that is the key words used. "IF YOU WANT TO USE" In designing something to be durable it is not a case of "if you want to use" its a case of, use the correct system or method that has been proven to last. I gave engine examples where a timing chain would never have been considered, why? I also give an example of the result of supposed components that were suppose to deliver, as stated in the above post. The ones cited, likely don't want to build or sell crap. The manufacture likely spent a huge sum of money to arrive at those components. In the end it is a design that will fail and is why you will not find a timing chain on an engine like in this video, it is really that simple.

https://www.youtube.com/watch?v=hMqZet0Lj9I

 

[SnTMan]

So gear drive I'd say

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[BrianPetersen]

So having a timing chain/belt is an engineering failure??

Just because some timing chain designs wear prematurely doesn't condemn the entire concept.

Gotta go. I have to drive to work in a car powered by a Fiat 1.4 MultiAir with a timing belt driven OHC 16 valve engine that has just short of 230,000 km on it.

 

[ACtrafficengr]

Kia is dealing with failing piston bearings. Their response is to reprogram the knock sensor to detect vibrations from bad bearings. If it detects the vibration, it limits the engine to 2000 rpm so you can limp to safety. It's a clever bit of engineering, I think, but I'd rather have good bearings.

My glass has a v/c ratio of 0.5

Maybe the tyranny of Murphy is the penalty for hubris. -

http://xkcd.com/319/

 

[moon161]

The mercedes OM61x and OM60x engines use a single timing chain

 

[Alistair_Heaton]

My W211 Merc engine had a chain. 6 cylinder 3ltr common rail CDI

300k km without a change when it got scrapped due rust. Engine was still sweet no drop in compression over the 6 years and 120k km I put on it

 

[BiPolarMoment]

Toyota, who's reputation is built on reliability, isn't doing themselves any favors rebadging a BMW as their Supra.

It is my impression that they did considerable modifications to the engine that made its way into the Supra specifically for reliability (if that's what you are concerned about).

 

[SwinnyGG]

So having a timing chain/belt is an engineering failure??

Why is anyone still engaging in this guy's threads

This is how it goes every single time.

 

[BrianPetersen]

Entertainment to poke fun at luddites.

My engineering failure successfully got me to a job site, and back to the office, despite the pretty big number on the odometer. Nothing bad happened.

 

[drawoh]

An excellent book on engine development during WWII is The Secret Horsepower Race by Calum Douglas. Very buggy Napier Sabres made into service because the British needed aircraft that could catch Fw-190s. Calem Douglas is an engineer and engine designer, so he understands the subject.

Another author on WWII engines, Bill Gunston, points out that all the important engines of WWII, were flying prior to the war. Some good aircraft were developed very quickly, but good engines take years. Douglas argues that Rolls Royce and Pratt and Whitney were successful during the war because they designed engines that were absolutely conventional, they debugged them quickly, and they spent the war souping them up.

--
JHG

 

[djs]

I had a European sports car that had a four cylinder engine with an overhead cam shaft. The cam shaft was driven with a timing belt and the camshaft also was connected to the power steering pump. Very funny feeling when you lose both drive power and power steering. Luckily that engineer was very easy to work on.


On a more modern note, the engine used in late model Ford Fusion sedans has/had a heating problem which would damage the head gasket. There is currently a factory recall on that issue.

 

[TugboatEng]

BiPolar, the funny part about BMW's engine problems is that they are for the most part very good engines. It's everything they attach to them that fails, plus the oil seals. I think their issues are mostly supplier related. Substitute a plastic resin or rubber type here and there and they have components that fail such as plastic water pumps/pipes and timing chain guides. Toyota has success used plastic parts on their engines but BMW seems to struggle. If BMW is building these engines for Toyota I suspect Toyota is going to inherent the BMW problems regardless of improvements made.

 

[Alistair_Heaton]

Sounds like the merc engine fine but everything around it rusts to death.

 

[enginesrus]

SwinnyGG (Mechanical)
Why is anyone still engaging in this guy's threads

This is how it goes every single time.
-------------------------------------------------------

The threads are meant to point out problems.
Why not just talk the technical and not the Personal about a person posting something here?

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drawoh (Mechanical)
6 May 22 16:33
An excellent book on engine development during WWII is The Secret Horsepower Race by Calum Douglas. Very buggy Napier Sabres made into service because the British needed aircraft that could catch Fw-190s. Calem Douglas is an engineer and engine designer, so he understands the subject.
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Yes great examples of excellent engineering, No timing chains there. The use of flammable metal in some of the engine parts though was not good idea for an engine in an aircraft(USA engines). Calum shows how those German engine builders did the best they could with the lack of proper materials.
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Quote (BrianPetersen)
So having a timing chain/belt is an engineering failure??
--------------
The people that assemble the product didn't design that system so, yes.
Just ask the people that purchased the product and had to deal with such
on a vehicle that they thought would last longer. Some have paid
10 times or more what a house would have cost in the late 50's for those vehicles.
The design is the cheap alternative to what would be a proper design. But of course
those savings are not past on to the consumer.
Many times the supposed cost savings by using an incorrect design ends up costing way more
than using the correct design. Use the example posted above or think Takata airbag.
The list could go on.

 

[TugboatEng]

As evidenced by leaking seals. brittle plastic, and biodegradable wire insulation the Germans are still doing the best they can with a lack of proper materials.

Speaking of an engine failure, the BMW N54 engine has my favorite. They used a NBR o-ring on the oil filter housing. This specific material has a very short life at engine temperatures and quickly loses resilience. This results in a leak from the oil filter housing which wets the serpentine belt. The serpentine belt is made from EPDM rubber which is actually quite a good choice for this application provided you can keep it from getting oily. Once oiled, the belt very quickly starts to degrade and shed it's reinforcement. Nothing too unique here yet BUT... The reinforcement cord pumps it's way through the crankshaft front seal and in to the oil pan where it clogs the anti-vortex strainer on the oil pump. This then starves the engine for oil, destroying it.

 

[BiPolarMoment]

I would be plenty annoyed that the oil filter was in a position to leak onto the serpentine belt in the first place--no normal mechanic is fastidious enough to keep that belt clean during an oil change regardless of the leaky o-ring that would be replaced concurrently.

 

[CWB1]

Griping about timing chains is a new one for me, I thought I'd heard it all but apparently not. Usually when folks gripe about the timing set its bc they have to spend the time and money to have a timing belt replaced as routine maintenance, or bc their engine was destroyed by a broken belt. Timing chain failures are extremely rare and I'd be surprised if any OE's were over 1%. Comparing either to a gear drive is meaningless simply bc there arent many (if any) production gear drives used in the light-duty market, and comparing light vs heavy-duty engines is apples and oranges. Most of my career as a tradesmen and a half my engineering ccareer was in HD engine work tho and anecdotally I can attest that gear drives do fail spectacularly.

 

[BrianPetersen]

Honda has built some motorcycles with gear driven cams. They howl! Very long gear train to the top of the engine.

Not aware of reliability being a factor.

And yes, I know, pushrods. No thanks. Not in that application.

 

[dik]

I don't know if I'm remembering this correctly, but I recall talking to a cab driver, decades back, and he was talking about an 'L' shaped engine, as I recall. I don't remember who manufactured it, but I understood it was one of the longest lasting car engines made. Is this myth? or incorrect?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

 

[JohnRBaker]

An 'L-shaped' engine generally meant that the intake and exhaust manifolds were both mounted on the same side of an inline engine's block. It was a rather common arrangement for larger straight-six and straight-eight engines.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

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