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The pre-chamber volume on an MB diesel is a good part of the combustion chamber volume. Not sure of the proprotion, but considerable air form the cylinder is forced in and expands back out. Much of the fuel burn actually occurs inside the pre-chamber.

This is another reason why ether isn't such a good idea on this type of engine -- the pressure oustide the pre-chamber can higher than inside during compression.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Lets keep the issue narrow and please keep responses confined to the question:

Have YOU ever seen a MB prechamber damaged by using a starting fluid.

Have YOU ever seen a Bosch MFI pump damaged by squirting water on it.

Your damage pictures have been cool but I saw lots of diesel damage while I worked at White Motor Company in Dallas. It doesn't concern my question here.

Quite frankly I don't believe that a tough arse part like a MB prechamber COULD be damaged by a starting fluid alone.

Why all the scare tactics without ANY first hand evidence.

__________________
You can get farther with a smile and a gun than you can with just a smile.

1984 300D
1985 300CD
1980 300SD
1993 SL500

My guess here is that you are missing the point being passed on to you. The fact is that people in this forum are running vehicles with very high mileage. They've gotten there as they've paid attention to the warning and cautions regarding what to and not to do with their engines. This goes along with religious maintenance. We do not need to "try for ourselves" to see what kind of damage can be done with starting fluid in a diesel.

The reality is this - ether is BAD for a diesel engine - even the direct injection ones. The 75 240D in my yard decided to lose fuel prime the day I picked it up. We cranked on it for over two hours trying to get that car started again. Finally, in despiration, the mechanic pulled out the can of ether to get it fired. I can tell you first hand that the car was NOT happy having that stuff shot down the intake. The starter bound on that stuff several times before the car finally caught on some fuel and ran on its own.

The moral is, if the situation is a life or death one, and merits the use of the stuff - use it CAREFULLY. Do NOT use ether as a means of "getting it started" just to avoid finding out WHY it's acting up to begin with. You WILL encounter engine damage with repeated use.

Ether can damage the prechambers as all but the smallest fraction of the air ingested during the intake stroke is compressed INSIDE the prechamber. The ether contains enough energy to blow th prechamber apart in the engine. It has happened - all you need to do is ask any diesel mechanic about ether damage to diesel engines.

Tirebiter,
While I support your "let's debunk the urban myth" intent, at some level you have to say that both common sense and a basic understanding of physics suggest that taking certain risks are just not smart. As an example, lugging an engine is generally considered to be a bad thing to do (I'm assuming you'd be willing to take that as truth and not myth) and most of us would try not to lug our engines. That said, how many of us have ever had an engine hand grenade due to lugging? Probably none. Does that make it not true? I'm willing to support the theory that ether COULD ruin an engine and will refrain from using it. The satisfaction of proving the truth at the expense of destroying my engine is clearly not worth it. While I defer to your obviously greater knowledge and experience, I'd also suggest that it's possible you never saw this kind of damage because the next stop for these cars (the few there may have been) was the junkyard and not your shop.

Since I spoke to the cold water on a hot engine theory I'll address that. As a fan of very old cars I believe it is well beyond urban myth that many years ago engines could be damaged if the coolant in a hot engine was refilled rapidly with very cold water. Engines today are far better made so it is reasonable to assume that that problem may no longer exist. However, I can speak to one instance where a friend cracked his exhaust manifold when he went through a cold winter puddle too fast. Did the water crack it or was it mostly gone already? (I have to admit the car was a Lancia so the latter theory is very possible) It's hard to say for sure. One thing I do know is that there are a number of sensitive and precision parts on our cars that are expensive and I would prefer to treat them with some respect. If you want to volunteer, I'd be happy to accept the results of a test where you get your engine nice and hot then douse it with ice water to see what happens. Perhaps we can expel this urban myth once and for all.

__________________
LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

It seems to me that Tirebiter's question is making these issues look more and more like religious dogma. I'm beginning to think of them as 'Diesel Metaphysics'.
To bastardize David Hume:
"When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or diesel metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames: for it can contain nothing but sophistry and illusion"

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I think before we take this too seriously ("dogma" just sounds way to serious) we should try to frame the argument so we can sort the answers into categories that make sense. Nature is not solely a black and white event, there are shades of gray and even colors. So don't expect the answers to questions to be black and white all the time.

First, a single molecule of ether that gets sucked into the engine is not going to cause it to blow up. You can do that over and over, all day long and it won't damage anything. Matter of fact, two won't either. So it is not ether itself that is bad for Diesel engines, it is more likely that ether in the hands of morons is bad for Diesel engines. Just like any other standard maintenance operation, if you do it wrong you can hurt yourself and ruin the engine, brakes, etc.

Lets be a little more broad minded about this issue and see where we would be if we applied the same logic to the rest of the stuff we commonly add to the engine. For example, we add stuff like gasoline and kerosene and other chemicals to the Diesel fuel (some pretty loosely defined stuff, by the way) to prevent it from becoming solid - is it ok to run the engine on these items instead of Diesel fuel? Could they destroy the engine? Yes, but do we ban them from the fuel tank because of that? No, we use some judgement knowing they are not Diesel fuel, follow the manufacturers instructions, or trust the kid at the station did.

I am not sure, but I think the energy content of Diesel fuel, being a liquid at room temperature and wanting to be a solid at below zero Fahrenheit (thus the additives needed) is probably greater than the same volume of ether, as a gas at these temperatures. So, I find it hard to comprehend how a small quantity of ether is going to destroy something as robust as an MB Diesel engine.

That said, and I believe you can safely pass a whif of ether across the air intake while cranking, I agree that if your Diesel does not start like the manufacturer intended, you should fix it. Who wants to lift the hood and have another person tagging along to help you get your car started all the time? And if it is really cold where you live or your battery dies all of the sudden, if you have a manual transmission unit you can "pop" start it as my daughter says. And you can do this by yourself if you think ahead a little and park aimed down a slope with enough room to just coast out of the spot. So, lets get a rant going on the use of automatic transmissions with Diesel engines. They even cause people to put ether in the intake upon occasion! So they have to be worse than ether alone!

I hope this helps. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

It isn't a matter of the energy content, it is in how it burns. Diesel burns much slower than ether, so the energy is expended over a longer time period. Thus, no sharp, "explosive", force is felt by the interior engine parts (prechamber, piston, etc.)

__________________
Keep everything as simple as possible-but no simpler--Albert Einstein

Not one single item of testimony from a first hand observer. Lots of off subject or partly related stuff though and indeed interesting but it does NOT address my two simple questions.

Please look up the word and definition of "hearsay".

Thanks for the physics lessons but I got my degree in physics from UT (Austin) in 1968. Then I found that I made a hell of lot more money working on exotic cars.

No opinions have been requested, only first hand facts, please.

BTW, I worked on Jerry Fairchild's Bosch bench for a couple of years, mostly gas MFI but some diesels also.

__________________
You can get farther with a smile and a gun than you can with just a smile.

1984 300D
1985 300CD
1980 300SD
1993 SL500

Jim Smith makes a good point that passing a whiff
of ether across the intake while the engine is cranking is NOT going to blow it. danger comes from using too much while the engine is NOT cranking. When I was by myself in a cold dark parking lot late at night without a cell phone and no one for a jump, I was a pretty sight: turning the key with one hand while directing a thin stream of ether across the engine to land near the air intake. It worked.

But I think I could have push started the engine too as it is my 84 300td with a front and rear hydraulic transmission pump, would transmit torque from the tranny to the engine like old, old GM Hydra matics that would start with a push.

Around this area we call ether 'smelling salts' for good reason: a little whiff will do you !!

Having said that I had a 81 chevy 350 olds diesel that refused to start the first time in the day without a hit of ether. Did that for 4 years.

We don't have any good local Roosta Master pump people around here.

__________________
71 220D 169K wrecked
83 240D 118K sweet 4 speed
91 350SDL (one of the 60% good engines) 156K
84 300d (loaner to my sister) 189K
79 300SD (partswagen)
86 420SEL partswagen
70 220d (partswagen)
68 280s GASSER!!! under construction now
85 300sd 310K miles winter beater car retired
93 300d 2.5 turbo 168K wife's car
83 280SL euro 5 speed 155K
69 250S newest project 54K

I repeat, rings and lands in peices after attempting to use ether to start a reluctant Ford tractor engine. Started only on pre-heat since, 30 years no trouble.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

asking for posts that ONLY deal with factual experiences is probably not going to work. Feel free to filter out what you don't like and use the rest. It occurs to me, though, that the discussions that result from some of the questions asked on the forum sometimes start some good thought processes.

Just my $.02 (and my apologies for not following your instructions),

Wes

I wholeheartedly agree with the Wes Bender’s sentiments but when statements are presented as fact rather than hearsay and are fundamentally flawed I do believe that they should be politely challenged rather than overlooked in the interest of tranquillity. Therefore please accept my humble apologies in advance if I tread on anyone’s toes!
In the same vein we could say: “Gunpowder can blow off your roof. Therefore you must NEVER strike a match in your house”.

Firstly ether burns with a soft yellow (cool) flame and obeys the same physical laws as gasoline, diesel, ethanol, kerosene, LPG etc. No need to take my word for it, you can safely try it yourself with a teaspoonful, but do it outside! Ether has a flashpoint at - 45ºC and a heavier-than-air vapor that can sneak onto the floor. I can promise you it will not “explode” in your face!
Quite so, Jim, and so do I. The volume of ether in a five-second aerosol burst, mixed as it is with propellant, is nowhere near sufficient to even turn a 3litre engine over at idle speed. Without the addition of diesel fuel you will get nothing more than a knock and a splutter. Ether with its cetane rating of 85-96 serves only to precipitate the ignition of the diesel fuel mixture in the PC by effectively raising its cetane rating. The ether vapor that remains in the cyl. will detonate early causing a very loud knock but that is quite harmless. To even suggest that it will blow the PC apart, melt or blow holes in pistons or break rings is just pure hogwash. These are maintenance and operating abuse issues that manifest after hundreds of hours, not a few seconds spray with ether. A well maintained engine regardless of mileage should never need to use a spray in US latitudes if you use a block heater. This is, in any case, a method of last resort and if you are ever stranded on an interstate in a snow blizzard it could save your life.
BUT- you must use the correct procedure for a diesel engine:
1)Disable glowplugs.
2)Just a touch of throttle and engine must be turning over before you begin to spray.

Model airplane diesel engines run on a mixture equal parts by volume of ether, kerosene and castor oil. My son had a 5cc diesel engine - more or less the volume of a PC. A 3mm wall steel sleeve pressed into an aluminum crankcase. I caught him once mixing the fuel 50% ether, he thought it would give more power and I guess it did! My grandson now uses that same engine in a boat and I’m still waiting for it to explode.

To answer Tirebiters other question:
No I haven’t, and cannot imagine what sort of damage you might be alluding to. I have had the Bosch, CAV and Simms agencies for over 30 years and can honestly say we have never had a pump in for service damaged in such a way. Water inside the pump, yes, and frequently! Fuel is constantly circulating from the tank through the pump relief valve back to the tank and this keeps the pump temperature between 50 and 60ºC under normal conditions. The metering elements are surrounded by fuel and are thus well insulated. Even ice cold water will have no detrimental effect whatever. But why use cold water? A dirty engine is best steam cleaned and when it is HOT!

That then is my two cents worth and I shall now slip quietly back into the ether.

__________________
Beagle

The one thing that stands out in the answers to my questions was that every reply was one aimed at preventing possible damage. That's pretty cool.

For the record: I only use starting fluid in the 3208 Caterpillar engines and the Merlin RR engines (gas) after a rebuild when I crank them up on the test stand. Once they fire and bleed out the last of the air, nothing further is necessary. I've had the same can of ether for over 10 years and that's been good for more than 30 engine start ups.

Thanks for the replies and concern. It makes this board fun to read.

__________________
You can get farther with a smile and a gun than you can with just a smile.

1984 300D
1985 300CD
1980 300SD
1993 SL500

Ether as vapor mixed with air is at least as explosive as propane, maybe more. It's easier to ignite, too, precisely the reason it's used for starting fluid. It burns almost as hot as propane, too, no chance you're gonna get a yellow flame! Blue, it you can see it, is more like it. Starting fluid is only about half ether -- the rest is a mix of light linear hydrocarbons to slow down the flame and provide some "omph" to start an engine.

Ether, in the presence of air and overheated, can explode pretty nicely -- when I was an undergraduate, there was an explosion in the chemisty building that seriously injured several grad students. Seems someone was refluxing some ether (boiling and condensing so that it drips back into the boiling flask) and the the joint between flask and condeser leaked. The vapor running down the side of the flask ignited on the ELECTRIC heating element (no shorts, no sparks, completely enclosed element). The entire aparatus exploded, serious burning everyone around it. By great luck, no one was facing it at the time....

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!