# honda 501 rototiller / honda gc160 engine idle problem



## xele (Jul 2, 2013)

Hi,

I just registered to the forum but use to visit it very often. 
I have an old Honda 501 Rototiller that worked perfectly, until I replace the engine for a new Honda GC160.
After replacing the engine, I notice there isn't a throttle on it and it runs at 3500 rpm all the time. The adjusting screw don't make any difference (either the governor's and the jet screw) and when the clutch lever is disengaged and I set the gears (any) the rotors start spinning before the engagement. The belt and the pulley are fine. I believe the engine is too accelerated and don't know how to adjust it.
If anybody has a hint of what might be going on, I'd really appreciate it.

Thanks!


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## AVB (Jul 4, 2013)

The forum members would the complete engine info so they see how the engine is setup to start with.

Here is an example the information needed.

GC160 PHA VIN# GCAH-1000001 TO GCAH-9999999


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## xele (Jul 4, 2013)

AVB said:


> The forum members would the complete engine info so they see how the engine is setup to start with.
> 
> Here is an example the information needed.
> 
> GC160 PHA VIN# GCAH-1000001 TO GCAH-9999999



sure,
what I have is Gc160 OHC GCAHA -3571656
thanks


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## LegDeLimber (Jul 5, 2013)

forgive me for asking what may seem a silly question
as I'm not familiar with the Hondas.

I spotted a PDF file (but lost the web page) 
and saw where it mentions that
the engine may or may *not* have a throttle control.

Does Your engine have the parts with the red tip that are shown in this pic?
http://www.brandnewengines.com/images/products/detail/Picture80708018.jpg
If not you likely have a fixed speed model.
if you saw more than one price for seemingly similar engines
and one was lower price, then this could be why.

There also could be limiter screws to set a range of throttle speeds
so look for them too.
This pic looks to have a top speed limit screw.
It's about two screw widths to the left of the edge of the air shroud 
and above the gas cap and choke rod
from the angle of view in the pic.

edit: i have a rear tine tiller and if the engine speed is much over idle
it will cause enough drag to begin spinning the pulley
and crunch gears when shifting them.
So I always have let the rpm's drop before shifting into gear.


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## AVB (Jul 5, 2013)

xele said:


> sure,
> what I have is Gc160 OHC GCAHA -3571656
> thanks



What you have then based on the serial number is a GC160A but there no OHC version listed. Your because Overhead Cam but most Honda engine are OHV (Overhead Valve). Double you block numbers again. Here is a list of all the GC160A that I found at my vendor's site that is in your serial number range.

GC160A DEAF ENGINE, USA, VIN# GCAHA-8000001
GC160A DHAF ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A MHA2 ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A PHA ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QBC ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QDE ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QEA ENGINE, USA, VIN# GCAHA-8000001
GC160A QHA ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QHA1 ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QHA2 ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QHAF ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A QHAJ ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A VHA ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160A VXA ENGINE, USA, VIN# GCAHA-1000001 TO GCAHA-3599749
GC160LA DHAF ENGINE, USA, VIN# GCAHA-3599750
GC160LA MHA2 ENGINE, USA, VIN# GCAHA-3599750
GC160LA MHAB ENGINE, USA, VIN# GCAHA-3599750
GC160LA QBC ENGINE, USA, VIN# GCAHA-3599750
GC160LA QDE ENGINE, USA, VIN# GCAHA-3599750
GC160LA QHA ENGINE, USA, VIN# GCAHA-3599750
GC160LA QHA1 ENGINE, USA, VIN# GCAHA-3599750
GC160LA QHA2 ENGINE, USA, VIN# GCAHA-3599750
GC160LA QHAF ENGINE, USA, VIN# GCAHA-3599750
GC160LA QHAJ ENGINE, USA, VIN# GCAHA-3599750
GC160LA QHC ENGINE, USA, VIN# GCAHA-3599750
GC160LA VHA ENGINE, USA, VIN# GCAHA-3599750
GC160LA VXA ENGINE, USA, VIN# GCAHA-3599750


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