Atco 12" Cylinder mower

[Darmic1 447]

It is! Its a 1948 model.......

It should have stayed there too! Driven me nuts today. When I rebuilt the engine I fitted a new coil, it had a good strong spark when I put it away before painting all the green bits. Finished putting the mower back together earlier and tried to start it...... nothing! No cough, no splutter, dead! Checked for fuel, yep! Checked for spark..... erm? no spark? Retimed the engine and flywheel, still no spark. Cleaned and regapped the points and spark now returned! So you would think it would run? No...... dead as a dodo! Have taken the carb apart, cleaned it and reassembled.....Gave up for today, Its far too hot to be thinking!!!

Ideas on a postcard please?

[Anglo Traction 1,016]

As requested-

 

 

 

[Darmic1 447]

Cheers Richard! 1....... What are you doing up at 3am? 2....... Whatever your on, I want some!!!lol

In answer to your postcard...... I have tried fuel straight in the plug hole, checked the crank case (engine was completely stripped and rebuilt) I made all new gaskets and used RTV gasket sealant to ensure an air tight crankcase and good seal to the barrel. The crank has no play/leaks in the bronze bushings, so compression is good. It also has good draw on air/fuel from the carb. I did rest the plug on cooling fins or bare metal to test spark, spark is regular, bright and strong so doubt its lost under compression.

My Dad used to work a lot on Villiers engines on old bikes, he seems to think its fuel related as the plug isn't very wet? There is fuel mixture getting through, some was present when checking crank drain plug. So thats where Im gonna start today, pull the carb apart and start from scratch! I have my 14" to compare with, It uses the same engine and runs a dream, so will set this engine the same and see what happens???

[Darmic1 447]

Finally got to the bottom of the non starting problem....... A mixture of a slightly moved flywheel and a poor seal on the crankcase drain plug. All is fixed now and running really well. Will get a video tomorrow, but for the meantime a front and rear photo....... 

[nigel 1,877]

once again a first class resto 

[Darmic1 447]

Cheers Nigel! Just the grassbox to do now and decals!

[Darmic1 447]

The grass box to this mower required a bit of work to make it fit this machine. It was from a later machine and had different brackets. Here is a photo after the modification and test fitting.

[Darmic1 447]

The grass box got finished today, all green and shiny!

 

 

 

 

[Darmic1 447]

Also had a small pressie from the 'postie' arrive today, all the way from Australia! Have placed the ones on the fuel tank and chain cover. Will fit those to the grass box in a couple of days, once the paint has hardened.

 

 

And with the freshly painted box fitted.

[Darmic1 447]

Here's a short video as promised.............https://youtu.be/gFFY3Uj0sAA

 

[Anglo Traction 1,016]

Look's like you made it to 3 am in the end Darren  . Excellent job on the Mower. Look's the Dogz....      What fuel/Oil ratio are you using in it ?.

[Darmic1 447]

Hi Richard, I was at work.... lol

Its running 16:1, but the oil is a 50/50 mix of modern low ash 2 stroke oil and the recommended sae30....... Have been told it would be fine on the modern stuff, but not so sure if any of the bronze eating additives are in it? So used sae30 mixed 50/50 to at least give some of the 'old' protection. Logic or not? It doesn't smoke very much, not like my 14" Atco does on pure sae30 mixed at 20+:1!!!

[Anglo Traction 1,016]

Hi Richard, I was at work.... lol

Its running 16:1, but the oil is a 50/50 mix of modern low ash 2 stroke oil and the recommended sae30....... Have been told it would be fine on the modern stuff, but not so sure if any of the bronze eating additives are in it? So used sae30 mixed 50/50 to at least give some of the 'old' protection. Logic or not? It doesn't smoke very much, not like my 14" Atco does on pure sae30 mixed at 20+:1!!!

16:1 is good for the motor's age.

I was apprehensive about using modern synthetics in these old engines and so I stick to the old mineral 30 or 40 weight.

The new stuff does not have the sealing capabilities needed in the plain shaft bearings (ok for modern ball bearings and Oil sealed engines)  .

They changed the design of the crankcase, bearings and added Thrust bearings somewhere around 1956 and allowed a reduction in Oil-fuel ratio.

Ring wear limit of > 1/32" is a common excessive smoke cause, but then a little blue haze is part of their character  .

 

I've been running several tests on certain Oils for some time with claims of corrosion to yellow metals in certain conditions..............no evidence found yet. 

 

Again, very impressed with the result of your work. Decals look superb repro's.    

[Darmic1 447]

Right!!!! I have now edited these posts about 5 times now and still cant get the pictures to appear the correct way around!!!! The only change is I am now running windows 10? Anybody else having issues????

[Anglo Traction 1,016]

I know nothing about modern I-phones or windows 10. To me, it look's like there is an issue with the format of the 'Portrait' image from the phone to the Window PC landscape default format ?. Both are 16-9 ratio, but are ar**s about face, so it lays the image on it's side and then embeds it that way on the Forum............Karl (nylyon) may be your saviour on this.

[Darmic1 447]

Sussed it!!! Windows 10 uses a different photo viewer....... have changed settings to use old windows 7 style viewer and resized all the images again, all is now well! WELL, I say well...... now have to edit the posts again..........

[Darmic1 447]

"Decals look superb repro's". They are...... Unfortunately not our Titch's fine work, but from a chap IN Australia, found on the bay of E. Ordered and delivered in just over a week!   

[Darmic1 447]

Stuck the box on the front and pushed it outside today for the final pictures......... Have a new project to collect tomorrow!

 

 

 

 

 

[Wristpin 400]

Hi Richard, I was at work.... lol

Its running 16:1, but the oil is a 50/50 mix of modern low ash 2 stroke oil and the recommended sae30....... Have been told it would be fine on the modern stuff, but not so sure if any of the bronze eating additives are in it? So used sae30 mixed 50/50 to at least give some of the 'old' protection. Logic or not? It doesn't smoke very much, not like my 14" Atco does on pure sae30 mixed at 20+:1!!!

y

It's my understanding that it's the additive in EP gear oils that may cause a problem with " bronze metal" and only then if run at high temperature.

[nigel 1,877]

Once again stunning

[Darmic1 447]

Thanks Nigel.......

Hi Angus...... Not sure 'y', it was suggested in a conversation had ages ago, that modern 2 stroke oils wouldn't provide the lubrication/sealing required for the oilite type bronze bush/bearing. As it is designed for more modern roller type bearings and seals. Im no expert on oils and the additives used within........ just applied a bit of 'bit of both' logic?

[Triumph66 1,256]

Beautiful workmanship and a credit to your skills.