Honda gx620 help

[Hemiwoodworker]

About to mount my Comet 780 but I don't know what size bolt to use. 3/8"fine thread is what most big blocks use. However I am only able to get 4 turns in and hit resistance. Up to that point the bolt runs in fairly smooth Can anyone verify what the correct bolt is for a gx620 is before I run a tap down this sucker!

 

[anderkart]

I'm thinking it might be tapped to metric., possibly M10.
The GX engines Honda "intended" to sell/ship to country's on the metric system had their PTO's tapped to metric. I wouldn't be surprised if some of those engines got shipped here to the USA by mistake... If you've got one of those engines, the PTO diameter will be a slightly smaller 25mm. size; instead of a full 1"...

Not sure which variant of the GX620 you have, but this spec sheet seems to be listing ALL metric hardware in the torque specs...

Honda GX620 K1 (20.0 HP, 14.9 kW) V-tiwn engine: review and specs

Honda GX620K1 - 614 cc (20 HP, 13.9 kW) V-tiwn general-purpose engine specifications: horsepower and torque, cylinder compression, valve clearance, oil type and capacity, service data and torque specs.

www.engine-specs.net

 

[Hemiwoodworker]

I have been on that site already but thank you. I've tried an m10 bolt but slightly too large. Think it's 3/8 just want to be sure