Simar rototiller irregular spark...HELP!!

hwinch5 · May 27, 2012

Hi, I'm a new member & I already have a need for your expert advice. I have an antique Simar rototiller first owned by my grandfather, then my father & now me! It has spark issues & will run briefly & then stop. It's about a 1946 model & not much on the web for repair help. How do I check condensor and or magneto? The points seem ok & I have fresh fuel every year. Any help with a Bendix magneto or ignition system help is much appreciated. Thanks!:confused2:

DJ54 · May 28, 2012

You'll probably have better luck looking for the engine model number, for repairs. Use Google search using the engine model and serial number.

I just found a ton of info on my approx. 1955 B&S Model 14 engine on my David Bradley 5 hp Special.

Are the flywheel magnets nice and shiny..?? If not try buffing with a Scotchbrite pad, or a medium Roloc gasket removal pad on a angled air die grinder.

If it still does it, make sure the spark is the issue. You say it runs briefly, but is that 1 minute, or 5 minutes..?? I've found on my Choremaster single wheel garden tractor, with a 2 hp Clinton engine, with the no-lead gas, it needs a capfull of Marvel Mystery Oil in the gas, to lube the valves. Within a couple of minutes, a valve will hang, and will not run.

Could be a weak condenser, or coil going bad. A condenser would be the least expensive to replace, if trying to eliminate items. Points may even be burned a bit. File and regap, or get a new set. Could even be the spark plug.

You'll be surprised what is still available out there if you have a part number for either. I was amazed Sears still has carb. parts for my DB still available through them, even though they are just standard B&S parts.

Google is my friend....

hwinch5 · May 29, 2012

Hey DJ54, thanks for taking the time to respond to my problem. Spark plug is new & points are filed. The Simar run time is est. about 20- 30 seconds. I'll check fly wheel magnets & definitely re-place condenser. I'm hoping to get our garden planted asap!

DJ54 · May 29, 2012

I did a Google search on your tiller, I've never seen one before. Found a page telling about the history on them. One thing definitely caught my eye, so copied, and pasting here. It may solve your issues. Definitely read the last sentence in the paragraph below...!!

This is the last version of the C5; horsepower has increased from 6HP to 8HP over the years. It has 2 forward speeds and 1 reverse. Like all SIMARs the engine is 2-cycle design

Here is a link to a fellow that collects Simars, maybe it will help to determine what yours is, or provide some info.

Switzerland

At the bottom of the page at this link address, the man says he doesn't have time to answer all personal emails, so started this forum: http://forums.delphiforums.com/n/main.asp?webtag=Rototillers&nav=start&prettyurl=/Rototillers/

May be an idea to join up, in case the problem is not resolved.

Now that I see it is a 2-stroke, and your using straight gas, it may just be the fact the cylinder wall is not getting lubricated, rings not sealing, and not enough compression to run, at least for very long.

In one paragraph from the link above, he say's every Simar he has seen, has a brass tag on I believe the left front. Should be a engine model number there. On the old Briggs engines, they had a lot of info on those tags. Valve settings, point settings, oil to be used in engine, etc.

Could be by a stroke of luck, those Simar engines may have had the same type of info. Most important, fuel mix ratio... I'm thinking at least 40:1 to be safe. But I'd definitely join that antique tiller forum. I'm sure one of those guys could give you the info for the fuel ratio.

Sure hope this helps..!! Let us know..!!

DJ54 · May 29, 2012

Just had a thought... Being if it is the case the cylinder wall is dry due to no oil in the gas to lube it, I'd be tempted to remove the spark plug, and give the cylinder 3-4 squirts of motor oil out a pump oil can.

Leave the plug out, and roll it over, maybe a dozen times or so. Let it set a bit, then turn it over again that many times. Allow the oil to seal things up.

Maybe add a half a pop bottle cap of 40:1 fuel directly into the cylinder, and replace the plug, and see if it will run. It will definitely smoke for a while, but will clear up...

hwinch5 · May 29, 2012

DJ54, sorry if I misled you, but I'm using mixed fuel & follow the owners manual / id tag recommendation for oil gas ratio. Thanks for the info on other forum: Antique Rototillers. I'll be sure to join. I will get you a progress report soon. :thumbsup:

DJ54 · May 29, 2012

No harm done, LOL... Good to keep the ole' brain working early in the morning.

3/4 of the fun of getting them running, is trouble shooting them, and figuring it out. 30 odd years ago when I was collecting/showing tractors and hit & miss, and throttle governed engine's, the old guys always said you need 3 things to make a gas engine run. Air, fuel, and spark, in proper proportions.

I am curious if the manual gives the point setting on the mag. I know on my IH tractors, it is .013 to .015. I usually set them at a nice fitting .014, and let it slide.

Also being that is a 2-stroke, just wondering if the exhaust port is nice an clean. I know many a exhaust port screens have been plugged on the high speed engines.

Hopefully just buffing the magnets on the flywheel, and/or replacing the condenser will solve the problem...

hwinch5 · Jun 2, 2012

UPDATE!!! UPDATE!!!
Success at last. I cleaned points once again & made the gap a little smaller. Made sure timing was perfect. It started first pull!!! I finally got garden rototilled & partially planted. Would be nice if the rain held off enough to get everything planted! Thanks again for the help & encouragement. H