oakum
New member
How does it work and why shouldn't you use it ad-lib?
Easi/cold start
- Thread starter oakum
- Start date
dnickj
Member
all depends on what you are trying to start - all you do is spray ether ( or some other flamable ) into the air intake to give the motor a helping hand with the bang
essexboy
Member
This has a lower "Flash point" and is Very volatile, spray near the air intake not into it ! Also make sure all naked flames e.g pilots are out A very small amount should do the trick. However this is only masking a basic problem with the engine, it shouldnt need it.
VicS
Well-known member
It works because ether, its main constituent I believe, has a very low ignition temperature (170C). That's NOT the same as flash point. So it will ignite in a diesel engine with poor compression or in petrol engine with a feeble spark.
You should only use it sparingly in an emergency because you have no control over the time in the cycle at which ignition actually occurs in a diesel engine so that could easily be far too early, especially if you have overdone it and lots is still hanging around after the initial few revolutions, resulting in damage to engine.
Overuse can also wash oil from the cylinder walls & valve stems etc
Frequent use will lead to the engine becoming addicted to it , it is sometimes said!!
(Ducks)
You should only use it sparingly in an emergency because you have no control over the time in the cycle at which ignition actually occurs in a diesel engine so that could easily be far too early, especially if you have overdone it and lots is still hanging around after the initial few revolutions, resulting in damage to engine.
Overuse can also wash oil from the cylinder walls & valve stems etc
Frequent use will lead to the engine becoming addicted to it , it is sometimes said!!
(Ducks)
Avocet
Well-known member
...But I think it is only ever said by people who think that using it should "fix" their engine for them in some way!
oldharry
Well-known member
Should not be used except as an emergency starting aid. It can (and has) blow a hole in the piston, bend con rods, damage or bend crankshafts because the explosion happens as soon as the cylinder temprature reaches about 175C as it is compressed. A diesel engine compression temperature can rise as high as 400C prior to ignition on cranking, so the ether explosion happens far too soon putting colossal loads on the engine moving parts.
'Addiction' certainly happens very quickly if it is used regularly, and is not entirely understood. I had a BMC 1.5 in a boat that had been regularly started with Easy Start, and it was extremely difficult to start without it from cold. After about 30 cold starts without easy Start, involving extended cranking before it would fire, it gradually became easier to cold start, until eventually it would start normally - unless it had been left for a month or more between runs.
'Addiction' certainly happens very quickly if it is used regularly, and is not entirely understood. I had a BMC 1.5 in a boat that had been regularly started with Easy Start, and it was extremely difficult to start without it from cold. After about 30 cold starts without easy Start, involving extended cranking before it would fire, it gradually became easier to cold start, until eventually it would start normally - unless it had been left for a month or more between runs.
Bilgediver
Well-known member
Others have said why not to use it AdLib which I totally agree with and yes it appears to break down the lubrication and so allow excessive wear at start up.
A not so violent substitute is already on board most boats....Try WD 40..
A not so violent substitute is already on board most boats....Try WD 40..
VicS
Well-known member
[ QUOTE ]
Try WD 40..
[/ QUOTE ] If it works all well and good but I am at a bit of a loss to see why it should.
Something that is based on ether works as already stated because it has a low ignition temperature (160 - 170C), that's the temperature at which the vapour will ignite without the application of a flame or spark, compared with diesel (250 - 270C)
WD-40 is apparently, according to Wikipedia, largely Stoddard solvent or white spirit. That comes in various grades in fact and I find ignition temperatures of 230 to 290C quoted, only marginally, if at all lower, than diesel. Also white spirit far less volatile than ether having a boiling point of 150 -190C compared with 35C for ether so to even get a useful amount into the engine the spray mist must be carried in via the induction system while ether will vapourise and enter as the vapour.
If it works then perhaps someone else can explain why it does.
Try WD 40..
[/ QUOTE ] If it works all well and good but I am at a bit of a loss to see why it should.
Something that is based on ether works as already stated because it has a low ignition temperature (160 - 170C), that's the temperature at which the vapour will ignite without the application of a flame or spark, compared with diesel (250 - 270C)
WD-40 is apparently, according to Wikipedia, largely Stoddard solvent or white spirit. That comes in various grades in fact and I find ignition temperatures of 230 to 290C quoted, only marginally, if at all lower, than diesel. Also white spirit far less volatile than ether having a boiling point of 150 -190C compared with 35C for ether so to even get a useful amount into the engine the spray mist must be carried in via the induction system while ether will vapourise and enter as the vapour.
If it works then perhaps someone else can explain why it does.
Nauti Fox
Well-known member
It does work (at least in petrol engines), along with various other aerosols, not sure if its the fluid or the propellant though.
VicS
Well-known member
[ QUOTE ]
It does work (at least in petrol engines),
[/ QUOTE ] I am not sure what the propellant is. LPG, butane probably, at one time but I think now CO2. Butane may well assist a petrol engine to start but wont do much for a diesel engine because it actually has a high ignition temperature. 420C according to my sources. That I guess is partly why the old fashioned battery operated gas lighters that we used to use for town gas don't work for lpg (town gas being partly hydrogen which has an ignition temp of 270C)
If the lpg propellant has been replaced by CO2 then its not going to do so well in petrol engines as it once did!
There is a move away from lpg as a propellant I imagine for a variety of reasons. Pure environmental, flammability and solvent abuse. That's after going over to lpg in some cases to replace fluorocarbons! So you can expect aerosol sprays that might have assisted petrol engine starting in the past not to do so in the future.
It does work (at least in petrol engines),
[/ QUOTE ] I am not sure what the propellant is. LPG, butane probably, at one time but I think now CO2. Butane may well assist a petrol engine to start but wont do much for a diesel engine because it actually has a high ignition temperature. 420C according to my sources. That I guess is partly why the old fashioned battery operated gas lighters that we used to use for town gas don't work for lpg (town gas being partly hydrogen which has an ignition temp of 270C)
If the lpg propellant has been replaced by CO2 then its not going to do so well in petrol engines as it once did!
There is a move away from lpg as a propellant I imagine for a variety of reasons. Pure environmental, flammability and solvent abuse. That's after going over to lpg in some cases to replace fluorocarbons! So you can expect aerosol sprays that might have assisted petrol engine starting in the past not to do so in the future.
Nauti Fox
Well-known member
From their website.
What is the propellant in WD-40?
A propellant is the stuff that helps pump WD-40 out of the can. The propellant used in WD-40 is carbon dioxide (CO2). CO2 is an inert gas which helps empty the can. Plus, the addition of CO2 reduced the number of VOCs, which helps preserve the environment. Be sure to point the spray nozzle toward the dot on the top of the can to ensure that the can fully empties.
And it still starts engines, mind you I may be veering off down a different path here as we use it to start a certain motorcycle that is renowned for having a lazy fuel pump and if its been standing for a long time it will go with a quick squirt down the inlets, but other than the pump everything else is ok, so may not work on a tired engine.
What is the propellant in WD-40?
A propellant is the stuff that helps pump WD-40 out of the can. The propellant used in WD-40 is carbon dioxide (CO2). CO2 is an inert gas which helps empty the can. Plus, the addition of CO2 reduced the number of VOCs, which helps preserve the environment. Be sure to point the spray nozzle toward the dot on the top of the can to ensure that the can fully empties.
And it still starts engines, mind you I may be veering off down a different path here as we use it to start a certain motorcycle that is renowned for having a lazy fuel pump and if its been standing for a long time it will go with a quick squirt down the inlets, but other than the pump everything else is ok, so may not work on a tired engine.
earlybird
Well-known member
In the interests of science, I have just applied a match to a spray of WD40 from the can nozzle. I got a flame about 3ft long. Does this prove anything?
VicS
Well-known member
[ QUOTE ]
Does this prove anything?
[/ QUOTE ] Yes the contents of the can are flammable. If its white spirit you'd expect that. Typical flash point 38C
Flammable liquid - A liquid that has a flash point of between 21 and 55°C
Highly Flammable liquid - A liquid that has a flash point of less than 21°C.
Dont confuse flash point and ignition temperature
Flash point - Lowest temperature at which a liquid or solid gives off vapour in such a concentration that, when the vapour combines with air near the surface of the liquid or solid, a flammable mixture is formed
Auto-ignition or Ignition Temperature - the temperature to which, under ideal conditions, a substance has to be heated to initiate self-sustained combustion, independent of any ignition source.
Definitions from Glasgow Uni website
Does this prove anything?
[/ QUOTE ] Yes the contents of the can are flammable. If its white spirit you'd expect that. Typical flash point 38C
Flammable liquid - A liquid that has a flash point of between 21 and 55°C
Highly Flammable liquid - A liquid that has a flash point of less than 21°C.
Dont confuse flash point and ignition temperature
Flash point - Lowest temperature at which a liquid or solid gives off vapour in such a concentration that, when the vapour combines with air near the surface of the liquid or solid, a flammable mixture is formed
Auto-ignition or Ignition Temperature - the temperature to which, under ideal conditions, a substance has to be heated to initiate self-sustained combustion, independent of any ignition source.
Definitions from Glasgow Uni website
double_ender
Member
Very interesting posts.
Presumably water would be described as highly inflammable
Presumably water would be described as highly inflammable
VicS
Well-known member
[ QUOTE ]
Presumably water would be described as highly inflammable
[/ QUOTE ] No! how do you figure that out. Confused by the fact that the words flammable and inflammable are synonymous.
Presumably water would be described as highly inflammable
[/ QUOTE ] No! how do you figure that out. Confused by the fact that the words flammable and inflammable are synonymous.
willie4646
New member
A lot of aerosols use Butane / Propane for the propellant gas and this is why a lot of them are flammable. I've started a Diesel on hair spray once with no ill effects. As an engineer I have never seen damage caused to engines by the correct use of easy start or similar products, in fact some of the diesel engines had ether cold start systems built into them (Rolls Royce Eagle) for example.
Willie
Willie
Vara
Active member
I wonder if things like WD40 work just on the fact that they are "bulking" up the compressible medium (air) thus effectively increasing compression and therefore temp.
And the fact that they are flammable is a bonus.
If this is the case then presumably any liquid as an aerosol would work, even water?
Just thinking aloud.
Any body got a knackered hard to start motor for research project?
And the fact that they are flammable is a bonus.
If this is the case then presumably any liquid as an aerosol would work, even water?
Just thinking aloud.
Any body got a knackered hard to start motor for research project?
earlybird
Well-known member
I think that the effectiveness of aerosols is down to the much better atomisation of the flammable substance compared with the fuel spray from the, maybe badly adjusted, injectors of an elderly engine. I have seen, from a little distance!, an engine started by playing a blowlamp down the air intake, but that's thread drift.
Billjratt
Active member
Well there's always SWMBOs hairspray if you're into aerosols but I like the idea of the blowlamp - especially if it was going, and has just been "blown out" thus giving a very similar vapour to that created by the cold start module on my perkins. I'll repeat a tip even if you're bored seeing it - Put your hand over the air intake and crank like bu@@ery at full throttle, the engine will go very fast due to decompression (no air to compress) and when you take your hand away. It will most likely start with clouds of excess fuel for a second or two, then ye'r aff.
BlueSkyNick
Active member
just don't use it on a diesel, not even in emergency, it could make matters worse not better.
I tried it on my old engine when the rings had gone - I was only trying to get her down to the boatyard to be fixed. The engine made some pretty horrendous noises and still didnt start. It went from being unreliable to a complete non-starter.
I tried it on my old engine when the rings had gone - I was only trying to get her down to the boatyard to be fixed. The engine made some pretty horrendous noises and still didnt start. It went from being unreliable to a complete non-starter.
