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Mills S75 starting problems

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Help! Mills S75 starting problems

Post  getback on Mon Feb 29, 2016 12:43 pm

Got this and cant get it to run acts like its hitting after a prime but i am not even sure of that because i havent heard it run i am useing fuel mix of 1/3 each either/castor/kerosene thats about 6-8 months old but has been in a air tight jar it burns good and blue and smells ok . What would the setting be for starting i have tried serveal and has good comp. also . The shut off spring is missing and I have checked that the fuel passage is clear , here is a write up on the engine from Ian and has not been taken apart to see if the liner is in the right position ? http://modelenginenews.org/cardfile/m75.html
 the subject [/url]                           Thanks for any advice , Eric
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Help! Re: Mills S75 starting problems

Post  navion34 on Mon Feb 29, 2016 1:42 pm

Try to blend fresh fuel... Ether is so volatile...

Rémy
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Help! Re: Mills S75 starting problems

Post  ian1954 on Mon Feb 29, 2016 1:54 pm

No matter what - you should be able to get it to fire following a prime in the exhaust port. You will hear the bark.

Turn the engine so that the piston covers the exhaust ports and then give the closed port a squirt of fuel. Gradually increase compression and reprime until it barks.

That is the best way to get into the ball park compression setting. Keep the needle closed for this.

If it doesn't bark - I would suspect the fuel.
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Help! Re: Mills S75 starting problems

Post  gcb on Mon Feb 29, 2016 2:26 pm

If you are worried that the liner is in backward you can loosen the nut that secures the venturi and unscrew the venturi. From there you can look in the hole and see the piston. Then reassemble.

To start it I would suggest closing the needle valve and starting with an exhaust prime. This will prevent flooding. Don't be afraid to add a little more ether.

For the exhaust prime, run the piston up until it covers the hole and apply just a drop on the side of the piston, then hand flip it smartly (at no time do you use a mechanical starter on these small engines). If it kicks, try again. If it does not fire, add a little more compression.

If you have no idea where the compression is set, turn the piston to its top position and increase compression until the contra-piston touches the piston, then back off compression one complete turn. This should give you an adequate starting point. If it is used, it should be close to the running setting.

Make sure you use a large enough prop. This is a long stroke diesel, not a glow. Smile

Is your engine a real Mills? Mine is an Aurora (India) replica...it starts easily and runs well.

George

Edit: Sorry Ian, guess I just echoed your advice.
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Help! Re: Mills S75 starting problems

Post  getback on Mon Feb 29, 2016 4:39 pm

Thank You and as soon as I find the special place I put the ether spray (starting fluid ) I WILL MIX SOME NEW I WAS THINKING THE SAME THING ((( BUT IT LITE LIKE WHITE LIGHTING SOOOOO STUPID CAP lock ,,, I am not sure about a bark unless its a small dog lolo!! No stuff I want this to happen I have been wanting to get that smell wee have heard of and a FF would bee the way to go with this . getback looking for ether Beer Cheers
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Help! Re: Mills S75 starting problems

Post  getback on Mon Feb 29, 2016 4:47 pm

gcb, I don't know how to tell the difft. from the two, You !! getback Babe Bee
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Help! Re: Mills S75 starting problems

Post  ian1954 on Mon Feb 29, 2016 5:05 pm

Great minds think alike!
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Help! Re: Mills S75 starting problems

Post  cox24711 on Mon Feb 29, 2016 9:08 pm

get a plastic bottle and put a tubeless tyre valve on the end of the cap and pop your fuel in there before you use it pump it up 10 psi and the ether vapour will condense and then shake it up! there you have fresh fuel for every time you run your engine p.s this was not my idea it was my friend of my at the club i go to and he did it with tin cans in the 40's problem solved for ether evaporating .you can use it in hot climates and pump it up slowly other wise it will get hot and might explode .also keep it in the fridge and only let the pressure out when you use it.

works will in aus when it gets up to 113'F!
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Help! Re: Mills S75 starting problems

Post  cox24711 on Mon Feb 29, 2016 9:13 pm

ahhh the mills 75 still looking but i have my eye on one Wink hope i get it!
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Help! Re: Mills S75 starting problems

Post  Oldenginerod on Tue Mar 01, 2016 4:30 am

getback wrote:gcb, I don't know how to tell the difft. from the two, You !! getback Babe Bee
I think the English Mills (original) had the black case and the Indian one didn't.  
I have an original.  I know it is because my brother got it long enough ago for it not to be a replica.  There were also the Irvine an Doonside Mills replicas as well as the Aurora.  Here's my original instuction sheet.
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Help! Re: Mills S75 starting problems

Post  getback on Tue Mar 01, 2016 8:48 am

Thanks Greg and Rod for the Info. I hope to find my ether and make up some new fuel today and try again . will ley you know and hopefully some video . Eric Babe Bee
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Help! Re: Mills S75 starting problems

Post  gcb on Wed Mar 02, 2016 10:32 am

Here are a couple of the India Mills .75's, note that I removed the tank on the second one for CL use.

 

George
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Help! Re: Mills S75 starting problems

Post  cox24711 on Wed Mar 02, 2016 8:44 pm

where did you get those curry mills? i cannot find any!
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Help! Re: Mills S75 starting problems

Post  gcb on Thu Mar 03, 2016 5:31 pm

Here is an Aurora Mills 1.3. The casting is pretty rough but the fits are good and it runs well.

I also included an Aurora Mills 1.00...I don't believe Mr. Mills ever produced this one. I think it is just an upsized .75.

George

 

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Help! Re: Mills S75 starting problems

Post  gcb on Thu Mar 03, 2016 5:36 pm

cox24711 wrote:where did you get those curry mills? i cannot find any!

What is a curry Mills? Never heard of that one.

George
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Help! Re: Mills S75 starting problems

Post  ian1954 on Fri Mar 04, 2016 3:20 am

It is a nickname for the Indian Aurora Mills engines.
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Help! Re: Mills S75 starting problems

Post  Oldenginerod on Fri Mar 04, 2016 5:46 am

Apparently one of the main weaknesses of the Indian Mills is the soft crankshaft which is prone to bend the threaded section on a crash landing.  Here's an excellent article about the repair.
http://modelenginenews.org/restored/curry_mills.html
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Help! Re: Mills S75 starting problems

Post  getback on Fri Mar 04, 2016 6:49 am

Well there is some disscusstion on this engine anyway ,,, I worked at starting the subject for about 2 hrs. and mantaged to get some barking and short SLOW porp speed runs , ... mixed up new fuel even added some extra ether after a few of these runs looks like it likes the comp. about 1/2 way but never acted like it would pickup fuel? I am sure i flooded it a few times but had compressed air to blow it out , the head was loose enough to remove so i pulled the liner to take a look the small row of holes are to the rear and seem to line up with the intake best . Why would it only run at a very low rpm ,if i tried to adjust anything it would cut off?? This is the ether i am using it says Heptane / Diethyl ether / carbon dioxide is this OK? It has a 8 " prop that got me once ! I also mantage to blow to much air into the fuel bowel and it poped off so i have to remove the engine from the stand and fix that . Any suggestions ...
Those are some nice looking engines George !
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Help! Re: Mills S75 starting problems

Post  gcb on Fri Mar 04, 2016 2:18 pm

getback wrote:Well there is some disscusstion on this engine anyway ,,, I worked at starting the subject for about 2 hrs. and mantaged to get some barking and short SLOW porp speed runs , ... mixed up new fuel even added some extra ether after a few of these runs looks like it likes the comp. about 1/2 way but never acted like it would pickup fuel? I am sure i flooded it a few times but had compressed air to blow it out , the head was loose enough to remove so i pulled the liner to take a look the small row of holes are to the rear and seem to line up with the intake best . Why would it only run at a very low rpm ,if i tried to adjust anything it would cut off?? This is the ether i am using it says Heptane / Diethyl ether / carbon dioxide is this OK? It has a 8 " prop that got me once ! I also mantage to blow to much air into the fuel bowel and it poped off so i have to remove the engine from the stand and fix that . Any suggestions ...  
 Those are some nice looking engines George !

Are you sure it was actually turning over? If the compression is too high, sometimes an engine will fire/backfire so that it appears to be turning over when it is actually rocking back and forth.

All starting fluids are not the same. In the US most seem to prefer John Deere because it has more Ether. I am not familiar with your brand...perhaps someone will address that issue.

An 8" prop should be fine. I think that's what I used for break-in. Being a long-stroke diesel, it will handle a wide range of props. Don't under-prop it.

George
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Help! Re: Mills S75 starting problems

Post  Oldenginerod on Fri Mar 04, 2016 2:41 pm

getback wrote:Well there is some disscusstion on this engine anyway ,,, I worked at starting the subject for about 2 hrs. and mantaged to get some barking and short SLOW porp speed runs , ... mixed up new fuel even added some extra ether after a few of these runs looks like it likes the comp. about 1/2 way but never acted like it would pickup fuel? I am sure i flooded it a few times but had compressed air to blow it out , the head was loose enough to remove so i pulled the liner to take a look the small row of holes are to the rear and seem to line up with the intake best . Why would it only run at a very low rpm ,if i tried to adjust anything it would cut off?? This is the ether i am using it says Heptane / Diethyl ether / carbon dioxide is this OK? It has a 8 " prop that got me once ! I also mantage to blow to much air into the fuel bowel and it poped off so i have to remove the engine from the stand and fix that . Any suggestions ...  
 Those are some nice looking engines George !
I'm assuming you invert the can & bleed off the propellant.  That gets rid of the CO2.  
What you have is heptane & ether.  You need to know is what the ratio if heptane to ether is. Consider the heptane as kerosene in you mixture calculations.  I wouldn't think the Pyroil product has enough ether.  Having said that, it is firing so there must be adequate.  Ether is more for starting than running.  It may be that low ether is causing you to have to over-compress to get it to fire, making it bog down.
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Help! Re: Mills S75 starting problems

Post  getback on Fri Mar 04, 2016 4:38 pm

Thanks I am leaning to the not enough ether it was not that $$$ The JD will bee and I Know where to get some ::Quack ; All starting fluids are not the same. In the US most seem to prefer John Deere ,will get some // and report back . It is a Mills engine and want to get it going !! getback
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Help! Re: Mills S75 starting problems

Post  smooth_bill on Sat Mar 05, 2016 7:30 pm

Eric,

I have a can of that starting fluid on the shelf. Found out the Ether content is very low, so I've set it aside to remind me not to buy something like that again.

John Deere may be more expensive, but is a known quantity. However, even JD is not as the label would indicate (80% Ether), because gassing the propellant off apparently leaves an Ether/Heptane mix, and not pure Ether.

When mixing future batches of fuel I'm going to assume the extracted mix is only 75% Ether, and adjust from there to get optimal fuel.

Bill

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Help! Re: Mills S75 starting problems

Post  gcb on Sun Mar 06, 2016 9:00 am

smooth_bill wrote:Eric,
John Deere may be more expensive, but is a known quantity. However, even JD is not as the label would indicate (80% Ether), because gassing the propellant off apparently leaves an Ether/Heptane mix, and not pure Ether.

When mixing future batches of fuel I'm going to assume the extracted mix is only 75% Ether, and adjust from there to get optimal fuel.

Bill


Perhaps some of the ether is expelled with the propellant. Some dispense it under a liquid such as remaining fuel or some kerosene to recapture any that escapes.

For such a small engine perhaps a quart of commercial fuel would work better until you sort it out. That eliminates one starting factor.

George
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Help! Re: Mills S75 starting problems

Post  getback on Sun Mar 06, 2016 9:30 am

well for one I didn't gas off the spray just straight into the jar out of the can/ I don't know about knocking a hole into the can with that ether in there ?!?!? Do you mean diesel out of the pump at the BP down the road ? Eric Huh...
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Help! Re: Mills S75 starting problems

Post  smooth_bill on Sun Mar 06, 2016 3:17 pm

I don't spray the John Deere fluid into an open container, but into a graduated bottle sold by Sally Beauty Supply. I prefer the 8oz (240cc size), and they are less than a dollar each.

http://www.sallybeauty.com/graduated-applicator-bottle/SBS-265100,default,pd.html

This requires a thin plastic straw (from on old WD-40 or similar spray can) which is pressed into the spray nozzle, and inserted into the tiny hole under the red cap on top of the graduated container. The opening is just the right size to let the propellant escape around the straw, but retain the fluid portion in the bottle. The last batch of JD that I purchased did not have the socket for the WD-40 straw cast into the nozzles, so I salvaged the nozzles from my earlier cans, and replaced the new nozzles.

Spray slowly with the JD can upright, and watch that the fluid does not foam up to the top of the bottle or it will spray out the opening in the conical nozzle of the bottle, and all over you! (Ask me how I know this)! Warm Always wear safety glasses or other eye protection (as I do) to protect your eyes!

Collect only the amount of Ether required for your fuel batch, plus the extra 25% or less to allow for the fact that the fluid collected is probably only 75 to 85% Ether. Too much Ether will not hurt your engine, and will make starting easier.

Pour your Castor oil into a second container, and slowly add the Ether from the first bottle. Note that when equal parts of Castor and Ether mix the molecules combine, and you may have very slightly less than the two quantities added up. I don't know how much the fluid level will be reduced, but measuring the parts separately will insure your proper proportions.

After the Castor and Ether are mixed, you can slowly add the measured amount of Kerosene from a third container, and pour the mixture into a metal can for storage. I also add 1 to 2 percent Cetane booster before sealing the can. I use Amsoil Cetane booster which is inexpensive although the smallest container it comes in is likely to last for many years, or a lifetime!

An equal parts mixture would require the following approximate amounts, which can be adjusted for your desired fuel formula if different than equal parts.

For 18oz of diesel fuel use:

Castor oil = 6oz (1/3rd of the total).

Ether = 7.5oz (1.5oz added to 6oz to compensate for the less than 100% Ether in the JD fluid that will burn like Kerosene).

Kerosene = 4.5oz (reduced 1.5oz because the portion of JD fluid that is not Ether brings it back up to 6oz total.

Correct me if the portions are not exact, but note that I added Cetane booster to the 18oz total, and you will end up with a mix that is slightly over 100% of parts. Looking at the various diesel fuel formulas published on the web - there is a vast range of portions used, so small errors are not likely to make a notable difference!

Bill
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