Thread: Hint for those who have trouble starting their chainsaws.

This also works well and has a much better name. It does exactly what it says on the tin

Start Ya Bastard Instant Engine Starter - Nulon Products Australia

I have no idea if it is true, but it used to be rumoured that these ether based products were addictive to engines. The theory was that they washed the oil off the cylinder bores, thus causing increased wear resulting in reduced compression and harder starting, encouraging their further use..... I suspect that it is unlikely to have any real impact (I have no evidence one way or the other!) unless used in huge quantity and frequency, but most of the time I find that the biggest starting issue with 2-strokes is "old" fuel. Way back in time, petrol used to last quite some time, but these days it starts to decay in weeks. After only a few months it can cause problems starting. I have also found that the ethanol fuel blends seem to eat the rubber hoses and primer bulbs, at least on Stihl equipment.

In all my small 4-stroke engines I use BP Ultimate, switch off the petrol and run the carb dry every time I use them - it helps to avoids the "varnish" deposits through the carb. In (Stihl) 2-strokes I use BP Ultimate with Stihl Ultra (synthetic) oil mixed at about 45:1 (aka a "safe" 50:1 !) but have taken to buying a small (and very expensive!) can of premixed "long life" fuel each year, and using it for the last run of my saws before draining them and storing through the summer - apart from occasional storm damage, most of our chain saw work is firewood cutting through the autumn and winter. This seems to largely remove any starting issues on all but Briggs and Stratton motors which always seem to be "stubborn" compared to Honda's.

The first tank or two of BP Ultimate I put through almost every (old) 4 stroke engine has caused problems. It seems to loosen all the years of crud in the fuel tank and pipes, causing blockages in the carb. After stripping and cleaning the carbs and fuel system this has never happened again.

We always buy and mix 2-stroke fuel as needed, never storing mixed fuel for more than a couple of weeks if possible. Unmixed petrol is used in other machines so is not normally hanging around fore too long. Even the "long life" premix is only rated for 6 months (perhaps a year, I can't recall!) or so once opened.

Around here the biggest issue for 4 strokes is the mud-wasps blocking up the carb vent pipes causing starting/flooding/stalling problems. These days in the summer I pull the vent pipes off and clean the mud out as a matter of course before even trying to start a motor!

Originally Posted by Warb

I have no idea if it is true, but it used to be rumoured that these ether based products were addictive to engines. !

Warb

I believe that notion stemmed from it's use with diesel engines where it can appear that way. What atually happens is that as the diesel engine wears the compression ratio decreases and the motor becomes increasingly hard to start from cold. Rather than becoming addicted to the volatile starting fluid, you could say it increases the life of the engine beyond what would otherwise require an engine rebuild. These fluids should not be used in conjuction with glow plugs (manual operation) or at all on motors wth automatic glow plugs, which are probably most modern diesels.

The fluid works well on recalcitrant small petrol motors such as chainsaws, brush cutters and mowers to quote just a few.

Regards
Paul

Originally Posted by Bushmiller

Warb

I believe that notion stemmed from it's use with diesel engines where it can appear that way.....

The fluid works well on recalcitrant small petrol motors such as chainsaws, brush cutters and mowers to quote just a few.

Indeed it does work! I normally have a few cans of Aerostart lying around for starting old engines that have been standing for many years. However for engines that are in regular use, I have found that some maintenance and care during the shutdown process usually prevents these starting issues. I know of some people who routinely use Aerostart to get a motor going, when there is clearly a problem that (to me, at least) needs to be addressed directly. Living on a farm, I regard Aerostart as an emergency "band-aid" to get me out of a hole (which it often does very successfully), and then fix the underlying problem for next time.

Interesting theory on the origins of the "addiction" rumour. The guy who told it to me, way back in the mists of time, was involved with performance petrol engines, especially 2-strokes, and it was the oil wash-out in 2-stroke motors that he was particularly worried about in the context of ether based starting fluids.

With regard to modern petrol, two weeks ago I tried to start a Land Rover that was happily running 10 months ago. It coughed a bit, but that was all. It would "run" with some petrol poured through the carb, but nothing more. Closer inspection revealed the (mechanical) petrol pump wasn't working...... but I was sure it was a recent replacement. To cut a long story short, the pump was fine but fuel pick-up in the tank had a brass (?) gauze filter around it, and this was 100% sealed with a green wax/plastic-like substance, that could be dug in to with a fingernail but was otherwise nearly solid. I have no idea if this was an algal deposit (it really looked like plastic not algae) but I have never seen anything like it. It's one of my vehicles, and was in regular use until 10 months ago, so I know the fuel pickup was OK back then. I can only assume it was a result of whatever they now put in petrol attacking the brass gauze. I mention this because I have watched people in similar "no fuel flow" situations run an entire can or more of Aerostart through an engine to keep it going whilst (I assume) they wait for it to miraculously heal itself.....

I use a product called Sta-Bil when I buy a new 20L drum of fuel and it seems to stop these problems up ere in the tropics.
Rgds,
Crocy.

Originally Posted by Old Croc

I use a product called Sta-Bil when I buy a new 20L drum of fuel and it seems to stop these problems up ere in the tropics.
Rgds,
Crocy.

I use a similar product, and I have no doubt that it (or something similar) is what Stihl use in their long-life premixed fuel - in fact they also sell, or used to sell, a fuel stabilising additive of their own. Like everything, it works "to a point". If the fuel has minimal air contact (i.e. a full tank) it will last better than if it has more air contact, this is why the long-life premix has a much reduced life once the can has been opened and the contents exposed to the air and moisture. A full petrol tank, however, has it's own downsides - not only is it expensive if we're talking about large (car) tanks, but these additives don't stop the ethanol and other "extras" in modern fuel eating some types of fuel hoses and some of the metals used in older engines.

I tend to fill two or three 20L jerry cans at a time, put the additive in those "full" cans, and I have found that those cans will be OK in 4-stroke motors for months. However for 2-strokes, as mentioned in my previous post, I buy fresh fuel and mix it as required (where possible!). I would guess that much of this comes down to the engines in question - old Land Rovers or low revving/low compression stationary engines will run on just about anything, most small Honda motors will do the same (I have pumps that have sat for two or three years and start first pull), but higher performance motors and 2-strokes are much more fussy.

I was taught a trick by my Dad when he gave me the job of mowing the lawn, if the motor becomes flooded turn off the fuel, open the throttle and keep pulling and eventually it will start when it goes lean enough. This has proven to be useful over the years but when we were racing a can of startng spray was quicker. Diesels got a squirt of petrol and they always started after that.

I still have some Redex left over from days gone by a couple of drops in my Stihl chainsaws & brushcutter does not appear to harm them that I can see moreover at the end of the season.
Brother had a Stihl agency back some yrs ago he put me wise with regard to fresh fuel.

After reading this interesting thread I thought I would share a my story of starting a diesel truck engine. It appears that large common rail truck engines become difficult to get started/bleed after running out of fuel. Our farm runs a road train powered by a 440 hp Detroit. It has on a couple of occasions run out of fuel and has taken much time and air compressors along with diligent use of aero start and a lot of swearing to get it going again. During harvest last month a miss judgement of fuel left in the tank and stopping on a slight down hill slope (the fuel pickup is towards the rear of the long tank) the big girl gave a couple of Coffs and stopped on the edge of town. The driver knowing of the previous troubles rang our local “go too”truck mechanic. This guy always has a squirty bottle full of Wruth brake cleaner fluid with him for cleaning parts. So he tells our driver “I’ll be there in five and I have a new trick to start those old barstards”.
So he turns up and put 2 jerry cans of diesel In the tank, told the driver to crank her over while he gentle sprayed brake cleaner in to the air intake to keep the engine just running until it bled the air out of the system and ran with out the spray. His comment was Brake Cleaner is a lot gentler on the engine then the ether Starting fluids. Ether seems to fire very hard and fast and I have heard a number of stories of broken diesels by excess use.
So one to remember.

I apologise for mentioning this story as it does digress a little from Ed's original lawn mower.

I have an old bulldozer, which now has not run for a good number of years since it broke a track. It is a diesel, but it has spark plugs, which I take great delight in telling people prompting them to tell me I am talking rot (normally they are not quite so polite): Diesels don't have spark plugs of course.

However, an International TD18 made in 1950 with a 691 cu in diesel motor (I think that is about 11.3 liters in the modern parlance) has a very primitive carburetor and spark plugs. The idea is that it is started on the petrol cycle and when warm after a minute or two it is switched over to diesel by closing a valve in the head which raises the compression ratio and supplies diesel fuel. The grey Ferguson tractor used a similar philosophy with petrol and power kero. Among the major manufacturers only International adopted this technique with their diesels. I found it very unreliable and quite frustrating so I took to starting it directly on the diesel cycle with a healthy quantity of a starting fluid. It worked every time. A six cylinder diesel with two unsilenced pipes sticking straight out of the bonnet make a a cacophony fit to burst ear drums and make you quake in your boots, but a thrilling sound nevertheless.

I am really not sure how modern diesels go with the quick start fluid. The danger is that they fire out of order, which is why the glow plugs, if fitted, must not be used with the fluid. Probably the vast majority of modern diesels have automatic glow plugs today so this definitely makes the use of starting fluid a no no. It maybe why Pete's mechanic in the story above preferred brake cleaner.

On petrol engines the fluid should be used sparingly: Just enough to start the engine as the spray tends to "wash" the cylinder leaving the lubrication less than optimum for a few revs of the engine. Over time this could conceivably cause wear. The starting fluid should be used for the emergency start until the starting ( or lack of starting) problem can be addressed.

Regards
Paul

Asking for a friend .....

How do "high RPM racing diesel engines" survive on high performance diesel fuels??

Such fuels may contain up to 35% Ether as it significantly changes the fuel performance to "improve starting and give a rapid throttle response."

Back in the middle of the last century my father worked as a driver on what he called a Navvy, basically a tracked machine with a loading bucket. He finished up very deaf and from my vague memory I can understand why. To start this thing they used to use petrol soaked rags applied to the air inlet but every now and then the inevitable happened and it swallowed one which never seemed to affect it too much.

In our 2010 trip to US/Canada we stopped into see an amazing private chainsaw collection the belonged to a bloke who was one of the top Stihl Engineers for North America. Amongst his 4000+ (nearly all running) chainsaws was an 60 year old diesel model. Starting was made possible by charging the hollow wrap handle with LPG, flipping a switch for a sort of temporary glow plug and opening a tap that allows the gas to get into the cylinder. Apparently the user could only run it for about 20 minutes before it turned their hands and arms to jelly. Mind you, lots of old big chainsaws will do that as well.

Originally Posted by Mobyturns

Asking for a friend .....

How do "high RPM racing diesel engines" survive on high performance diesel fuels??

Such fuels may contain up to 35% Ether as it significantly changes the fuel performance to "improve starting and give a rapid throttle response."

Because they are designed from the ground up to utilise such fuels..........

A friend of mine (who I haven't seen for years because he lives on the other side of the planet) has a couple of drag cars. The last time I spoke to him he was playing with a "top alcohol" engine which burns 100% alcohol (methanol). BP currently put up to 10% alcohol (ethanol) in their road car petrol, and say it is suitable for all cars made after 1981 (from memory). Older engines need higher octane fuels, lead additives and so forth, it just comes down to what they were designed to use. Those high performance diesels are designed to use a particular fuel mix. Out of interest, a diesel engine will run on a diesel/petrol mix but above a certain % petrol it will run but not start. It's not recommended, but it is possible - I learned this many years ago from a guy who owned a petrol station and had to deal with people putting petrol in diesel vehicles.