kieronriley
Well-Known Member
what does WD 40 do to assist in starting a diesel engine, is it the propellant gas that has a much lower flashpoint than diesel or is it the wd 40 itself that adds to the compression. thanks for reading. Kieron
WD 40 starting engine
- Thread starter kieronriley
- Start date
VicS
Well-Known Member
What counts in starting a diesel engine is the auto ignition temperature, not the flash point
For diesel that is 210C,
white spirit, believed to be the main constituent of WD40, a little higher at 230C
(There appears to be no data for WD40 itself)
The propellant is now carbon dioxide but at one time was methane (IIRC) which has an auto ignition temperature of 580C (It may have been butane. If so the auto ignition temperature is 405C)
There appears to be no reason why WD40, past or present will assist in starting a diesel engine.
Easy start contains diethyl ether which has an auto ignition temperature of 180C
Flash point is the relevant property when starting a petrol engine
Table of auto ignition temperatures here Fuels and Chemicals - Autoignition Temperatures
and flash points here Flash Points - Liquids ( note in °F)
For diesel that is 210C,
white spirit, believed to be the main constituent of WD40, a little higher at 230C
(There appears to be no data for WD40 itself)
The propellant is now carbon dioxide but at one time was methane (IIRC) which has an auto ignition temperature of 580C (It may have been butane. If so the auto ignition temperature is 405C)
There appears to be no reason why WD40, past or present will assist in starting a diesel engine.
Easy start contains diethyl ether which has an auto ignition temperature of 180C
Flash point is the relevant property when starting a petrol engine
Table of auto ignition temperatures here Fuels and Chemicals - Autoignition Temperatures
and flash points here Flash Points - Liquids ( note in °F)
Refueler
Well-Known Member
Original WD40 was said to be kinder to cold start a diesel. But todays 'environmentally friendly' WD40 is useless for this.
I have a pal who has a Lancia diesel MPV ... he always had a can of WD40 for winter starts ... but since the re-formulation - its never worked and has had to go back to 'ether' based Easy Start.
Sad really - as that was the only good thing about WD40 ..... now it doesn't cold start a diesel - its just a can of crap !!
jamie N
Well-Known Member
Refueler! What sacrilege is this that you utter?
WD40 smells great, and does have a faster propellant speed than most other sprays of this type, which does get rid of carp on the spot you're cleaning!
As for a penetrating fluid; yup, you've a point, I agree. I used a lot of it on underwater connectors, and it was very good at that, but most folks don't have that issue to deal with.
Didn't the best rumour about its constituent formula concern cod liver oil, " 'coz that's good at dispersing water too"!
WD40 smells great, and does have a faster propellant speed than most other sprays of this type, which does get rid of carp on the spot you're cleaning!
As for a penetrating fluid; yup, you've a point, I agree. I used a lot of it on underwater connectors, and it was very good at that, but most folks don't have that issue to deal with.
Didn't the best rumour about its constituent formula concern cod liver oil, " 'coz that's good at dispersing water too"!
Beneteau381
Well-Known Member
Iirc it had a propellantthat auto ignited nicely, nowadaysit doesnt so it doesnt workRefueler! What sacrilege is this that you utter?
WD40 smells great, and does have a faster propellant speed than most other sprays of this type, which does get rid of carp on the spot you're cleaning!
As for a penetrating fluid; yup, you've a point, I agree. I used a lot of it on underwater connectors, and it was very good at that, but most folks don't have that issue to deal with.
Didn't the best rumour about its constituent formula concern cod liver oil, " 'coz that's good at dispersing water too"!
ltcom
Well-Known Member
VIC s is legendary. Easy start. Then fix the problem when / if posdible
Bilgediver
Well-Known Member
It is still fine for starting old cars with wet H. T. leads if nothing else.
Refueler
Well-Known Member
Years ago when I Club raced my Capri .. in return for garage equipment use for maintaining the car ... I used to sort out ignition / starting problems on customers cars .... most car mechanics hate that side of work. One of the common problems found was the overzealous use of WD40 .... this is the days of the mechanical distributor. Usual fix was to dismantle and wash / clean and dry .. re-assemble. Then politely tell customer to retire the use of WD40.
That work actually led to my meeting first Wife ....
