Honda gx630 replacing kohler 9.5

[HaroldSiefke]

I am about to put a gx630 honda motor on my mill, replacing 9.5 kohler. I was wondering if I'm going to have to change the pulley on the motor to make the blade spin faster or if I can leave it how it is? I have 19inch band wheels and a 3  1/2 inch pulley on motor. Will this work or do I need to buy a bigger motor pulley?

[sawguy21]

No need to speed up the mill unless you want to. Both engines max out at 3600rpm but the big Honda won't even notice the load. Using that on a machine designed for a 9.5 is sortta like shooting squirrels with a 12 ga.

[HaroldSiefke]

I was thinking that I should get the motor I want. Cause when I build my bigger mill I will have the motor for it.And even with this mill I sure could use a lot more power. I figure its pretty close to the Lt15. It cuts 2inches smaller log diameter then the Lt15. I don't want to buy a 14hp and find its not big enough....

[ladylake]

If your band speed was kinda slow with the old motor I'd go a litte bigger on the driven pulley, main reason is I think a 3-1/2 will slip too easy with the extra power.   Steve

[thecfarm]

Is that the 20hp model? I have some sort of gx on my mill. I do know it's 20hp.

[pineywoods]

That 3 1/2 inch pulley oughta be just about right. Don't want to lug the motor..

[HaroldSiefke]

Is that the 20hp model? I have some sort of gx on my mill. I do know it's 20hp.

Ya it a 20 horse power 8)

[pasbuild]

I ordered my mill with the Honda 20hp, I had nothing but trouble with it until I changed out the carburetor with an after-market carb.

[thecfarm]

Harold,don't be alarmed you made a good choice. I've had my for 8 years maybe. I only saw for me,so it sits there just waiting for me. Once it sat for 3 years.  :  I did have to replace a fuel pump on it. It was still running but leaking. That is all I have ever done to it. It is fussy on when the plugs get bad. Won't run good at all. seems like I go through more plugs than my other motors.

[hamish]

Harold,

Just a few points to consider.

You will be adding alot of extra weight by using a GX620/630 on your existing mills.

Do you have a plan for the added weight?

Plan for the exhaust routing?

Have you ever had to work on a 600 series motor?


Personlly myself I would be lloking at either a GX390 (13HP) or a CH440 (14HP).
Very little added weight, and two durable motors.
With the size or your mill, I fail to see the advantage of jumping to 20hp.

When you build "your" mill, shop for the engine at that time.

I have a Norwood ML26, rated for 26" diameter logs, have whittled away some 31" one on it, cut every native hardwood to my region on it and for a manual mill my GX390 does it all.

20hp on a non manual mill, makes sense to me.  When I push my motor hard I see the results, it is surprising what it will take.  Many of us with manula mills dont push enough to get that certain "cuttin music". In the mean time are heating the be-jebers out of our bands.