# Craftsman snowblower with a Tecumseh engine



## Craftsman27 (Jan 25, 2014)

So my snowblower has been hard starting. I don't ever remember changing the spark plug (sorry guilty). The plug that was in there was a Champion RN4C. The manual states Champion RJ19LM. I replaced it with another RN4C. This snowblower was purchased new. Some of the info on the net states that if it is a Tecumseh engine it should have the RJ19LM. The difference in the plugs is that the RN4C has a longer "reach" 19mm versus 9.5 mm for the RJ19LM. Has anyone else experienced this? It is a 26" Craftsman snowblower purchased maybe sometime in 2007. Thanks


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## crazzywolfie (Jun 2, 2014)

as long as the piston or valves don't come in contact with the spark plug it should be good but the rj19lm is very commonly used on Tecumseh engines. i don't think i have ever seen a different plug in one of these engines unless someone else put a different plug in.


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## Grunt (Nov 11, 2013)

The RN4C spark plug is for a (OHV) overhead valve motor and I'm guessing you have a flathead which does use a RJ19LM or J19LM plug. The RJ19LM plug, being shorter, will put the spark closer to the incoming fuel mix and probably make starting easier. I don't know the distance between the head and piston, but I'm surprised the spark plug didn't hit the piston. Page 62 lists the plugs used for different engines.


http://www.barrettsmallengine.com/manual/tecumsehreference.pdf


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## Dauntae (Nov 10, 2016)

Do you have the Tecumseh OHV engine as that would take the longer plug, the short plug goes into the flathead engine.


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## Craftsman27 (Jan 25, 2014)

Sorry for this question - how do I confirm if it is the OHV engine?


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## crazzywolfie (Jun 2, 2014)

you will have a valve cover somewhere if you got OHV engine. if the area around the spark plug looks like this it is not a OHV engine


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## JLawrence08648 (Jan 15, 2017)

If you have a OHV engine you will see a small cover projecting from the engine on the side, probably 1 1/2" w x 3"-4" l x 1"-1 1/2" h. Out can also be a 4"x4" hex box sticking out.


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## Dauntae (Nov 10, 2016)

Here is a pic of a 11.5hp with heater box taken off, you can see the L shaped tank and the small black valve cover right in the middle.


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## HCBPH (Mar 8, 2011)

If purchased in 2007, I'd bet it's an OHV engine. Most significant difference is on most (if not all) the cylinder is angled while on something like the older Tecumseh flathead engines, the cylinder is vertical.
The picture is of a Tecumseh 10 HP I redid the other year, that's a flathead engine.


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## Craftsman27 (Jan 25, 2014)

HCBPH said:


> If purchased in 2007, I'd bet it's an OHV engine. Most significant difference is on most (if not all) the cylinder is angled while on something like the older Tecumseh flathead engines, the cylinder is vertical.
> The picture is of a Tecumseh 10 HP I redid the other year, that's a flathead engine.


It is a OHV thus using the RN4C plug - thanks to all for your help - maybe the carb needs to be cleaned


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## vinnycom (Nov 6, 2017)

hard staring is usually related to fuel/air mix, yes, cleaning the carb is the first thing to do especially if fuel was left in it for a prolonged period of time and make sure all passage ways and holes are cleared and also check everything between fuel cap and intake manifold


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## Craftsman27 (Jan 25, 2014)

Can someone confirm the gap on the Champion RN4C plug ? Thanks


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