Dangers of aerostart

**Blknight.aus** · 13th November 2010, 08:54 PM

Used as a cold start aid its ok well ish...

the problem is that the ether in them (which is why it works on sheep) lights up too easily. Usually in a diesel the fuel doesnt turn up in the compressing air till its ready to be ignited so but the areostart will be there from the get go so once the areo start lights off which is usually well and truely before the nominal injection timing it start trying to push the engine back the wrong way.

while ether isnt known for its huge energy content when lit off if the ether is the only thing burning the inertia of the crank and everything else will keep everything turning over the right way and the next pot in line will be moving a lot faster from whats left of the areostarts combustion kicking the first pot down. Once the areostart starts the fire usually the diesel being injected also comes into play and away the engine goes.

The problems come when theres leftover liquid diesel hanging around after the exhaust stroke (say from dribbly injectors) and the areostart lights that off while the piston is still on the way up. Think of it as pinging in a petrol engine but worse.

You mentioned that the compression is ok But is it really? whats it test at on a compression test anything less than about 300 PSI just isnt going to cut it to light off diesel without a good belt from the glow plugs and at least a couple of injectors patterning near enough to correctly.

Is the starter flinging the crank over quickly enough? as a rough rule of thumb if you cant hit 300 rpm on the starter you're not likely to get a good start.

Are the glow plugs working correctly? if you have series wired glow plugs and one has a dodgy connection the current being passed through them wont be enough to make them glow correctly even though the voltage will test as though they are, ditto for parallel wired if the relay or switch contact is acting as a resistor your not going to get a good glow.

you could also try the following if you dont want to resort to areostart.

1. remove the plugs put about 20ml of engine oil into each pot wind the donk over on the starter till they just about stop spraying oil out, drop the glow plugs back in glow it and start it.

2. hook the fuel system up to a temporary tank and try about 100ml of petrol into 1l of diesel rebleed and have a go at at starting on that.

3. tow start it get the vehicle (if you can) up to near max governed RPM's in 2nd gear and drop the clutch on it

I suspect that if it started a month back and got a good run and now wont restart that you have water or contamination in the fuel and thats causing the problems a damn good bleeding should see a start. Diesel snot would be my first suspect and being indirect injected my guess is that its on a VE type pump and some of the snot has made it into the rotary pump in the injector pump and its not priming correctly. Flushing it up with diesel heavily laced with a biocide treatment should clear most of it after which it should start up pretty much straight away.

**B92 8NW** · 13th November 2010, 09:01 PM

Originally Posted by rovercare

Don't spray to much though, aerostarting an indirect injected diesel to get it to fire will cause it to pre-ignite, like trying to start a petrol with to much timing advance.....well thats my experience anyway

Hell

. Maybe I'll try a heat gun down the manifold first.

**B92 8NW** · 13th November 2010, 09:14 PM

Thanks Dave. It's an inline Bosch PE pump. Supposedly these are a ***** to bleed but there seems to be a good squirt from the injector pipe unions. The oil in it is like grease and certainly wouldnt be helping the cranking speed but I'm trying to get it started (and warmed) to give it an oil change anyway.

The glow system is mess. The original timer relay isn't working so it's been jury rigged with a button in the cab. I've got a spare D1 glow relay timer and loom so I'm thinking of wiring that in, not sure if the relay will handle 6 glow plugs though.

**Blknight.aus** · 13th November 2010, 09:30 PM

its not that hard to bleed providing you have some way of getting decent positive pressure to it from the tanks side...

you only need to get a couple of pots firing, in a pinch just use a jumper cable direct from the battery to the glow plug rail if its 12v parallel wired and leave it there for about 40 seconds prior to trying to crank it, No cheating and guessing, use a stopwatch, 40 seconds is a LONG time to glow an engine. leave the jumper on while you crank it but pull it as soon as its running, you will want damn good batteries.

if its series wired jumper it to the glow plug end that doesnt have the earth lead on it but dont use a jumper lead use a bit of 6mm2 wire wait till its hot to the touch and then crank it over for a start.

fozzy has 3 working glow plugs and when the system is working (dodgy electrical connections in the bridging leads) a 15 second glow on 3 plugs gets me a start within 5 seconds of cranking it then runs rough for a handfull of seconds while the #1 pot sorts itself out and starts to fire.

**LandyAndy** · 13th November 2010, 09:56 PM

Originally Posted by circlework

Stone the bleedin' crows! Did I read that right??

So, what happened to shearer pride? Do they still get a premium to shear sedated rams??
Geeez, wtf is happening to our country!! The namby pambys are really pizzlin' me off lately! Heck, next thing you know, boyz'll be marrin' boyz and girlz'll be hitchin' t girlz!

Sorry, hijack over, back to topic.

Cheers.

I belive it has become a worksafe issue.Yep they still get double or what ever it is these days.
Too many back and other injuries.
Andrew

**mark2** · 14th November 2010, 10:27 AM

I have an old cruiser ute with a 6 cyl H diesel. The glow plugs are dead and it wont start from cold without aerostart. Its a farm truck and $50 worth of new glow plugs would be over-capitalising...
Likewise for my old 414 tractor. Neither seem to suffer any ill effects.

I also use it on various recalcitrant small engines to save wear and tear on pull start mechanisms, especially if the fuel is a bit stale.

I think the comment about it being 'addictive' probably stems from the fact that aerostart will mask various tuning and mechanical issues, which tend to get worse, not better.

In my view, it definitly has its place, particularly for older machinery which it isnt worth spending money or time on and for which the very small risk of damage isnt worth worrying about. Also at times when a starting battery is dodgy and only has one or two cranks in it, aerostart will save the day.

**circlework** · 14th November 2010, 12:07 PM

Originally Posted by mark2

I have an old cruiser ute with a 6 cyl H diesel. The glow plugs are dead and it wont start from cold without aerostart. Its a farm truck and $50 worth of new glow plugs would be over-capitalising...
Likewise for my old 414 tractor. Neither seem to suffer any ill effects.

I also use it on various recalcitrant small engines to save wear and tear on pull start mechanisms, especially if the fuel is a bit stale.

I think the comment about it being 'addictive' probably stems from the fact that aerostart will mask various tuning and mechanical issues, which tend to get worse, not better.

In my view, it definitly has its place, particularly for older machinery which it isnt worth spending money or time on and for which the very small risk of damage isnt worth worrying about. Also at times when a starting battery is dodgy and only has one or two cranks in it, aerostart will save the day.

+1

Works really well on things like 12hp petrol stationary engines that have had 12 months annual leave. Try pulling on one of those 20-30 times. One sniff and they start like they only stopped yesterday.
Starts diesels well, but, don't like the knocking. Saving me a few grand in reco costs though and if I did reco it, I'd never see the money again, as I don't use the backhoe often.

Hope it works out ... if it was just a once off, I'd give it a go.

Cheers.

**Blknight.aus** · 14th November 2010, 12:34 PM

Originally Posted by mark2

I think the comment about it being 'addictive' probably stems from the fact that aerostart will mask various tuning and mechanical issues, which tend to get worse, not better.

Ding, give that man a prize.

Originally Posted by mark2

In my view, it definitely has its place, particularly for older machinery which it isnt worth spending money or time on and for which the very small risk of damage isnt worth worrying about. Also at times when a starting battery is dodgy and only has one or two cranks in it, aerostart will save the day.

its excellent value on any petrol engine Ive even used it to start motorbike engines that have been flooded by way of immersion without having to get the tools out, Whip off the air filter, spray it heavily while its cranking and after about 20 seconds away she goes put the wet filter back on while its at a fairly high idle and let it dry the filter out. Dont do that on an engine you like though.

If you want a good demo of the pre ignition effect of areostart in a diesel get one of the small 5hp pull start units and try to pull start it while someone feeds it areostart. Pull the cord with your non master hand, otherwise you wont be able to type up the results untill after your hand/arm heals.

**nayto** · 14th November 2010, 01:48 PM

Just give it a go with any aerosol that is flammable just about, sure.... its not good practice but it works.
Think Fly spray, CO cleaner, most will work. The donk will handle it no worries. I've used it on many engines from tiny little air cooled listers that have no priming pump, to massive Cat Cummins and Detroits. Spray away

**justinc** · 14th November 2010, 07:10 PM

Originally Posted by nayto

Just give it a go with any aerosol that is flammable just about, sure.... its not good practice but it works.
Think Fly spray, CO cleaner, most will work. The donk will handle it no worries. I've used it on many engines from tiny little air cooled listers that have no priming pump, to massive Cat Cummins and Detroits. Spray away

Certainly, just spray away, its an 'H' series diesel for goodness sake. Can't kill them with a big stick but they MUST have good preheat. I've poured boiling kettles over the inlet to get them going before, but a shot of 'gas' won't hurt. all that cranking will at least have some oil around the big ends/ mains etc.

The only thing apart from hydraulicing them that will kill them is shearing the spline off the oil pump drive on the crank nose....

JC

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