Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Hi folks,

I switched out my regular SunDec hour meter which was on my Toro 828 LXE for the tach/hour meter version that I was going to use on a 17 hp lawn tractor this spring.  I did this out of curiosity to make sure my engine is running at its rated speed, whatever that is.  At idle, my 8hp L-head engine runs at about 2,300 RPM and at full operating speed, read at about 3,350 Rpm's.  I'm not so concerned about the idle, rather if the operating RPM is correct.  Does anyone know what percentage of error these meters are rated at that simply tap off the spark plug wire?  I want to make sure the engine is producing the correct amount of power.  Thanks.  

Richie, could you mean SenDec instead?

Marshall wrote:

Hi Marshall,

Yes, I didn't notice my typo.  Thanks for correcting me.

My book says to see microfiche card #30 for correct RPM.

http://www.farmex.now.tc/catalog/product_info.php?products_id=179

This ad says 3600 RPM.

Hi Robmints,

That motor is a 9hp, my Toro has the 8 hp L-head engine.  Do you think the operating RPM of the 9hp would be the same as the 8?  Also, would you know of a RPM meter I can use to check against my SenDec tach/hour meter.  I can check RPM with my diagnostics equipment for a car, but I would not know what to use for a single cylinder engine.  Even with the Mobil One oil I put in it yesterday, the operating RPM is still 3,350.  If you are correct and it should be 3,600 RPM's, then it's one of two problems;  the engine is not running at the correct RPM or it is just a shortcoming with the SenDec meter.  I like to think its just the hour tach/hour gauge because the engine runs excellent and throws snow further than any snowblower I've seen.  Any suggestions?  Thanks.

That 3600 may be Max RPM? Can you take you throttle (at the carb) at push it forward to rev it up higher, then check it.