Restoring 1970's Max IV

[howdah]

Hi

I have a max IV which has given good service over the years on the hills of scotland, one thing i would like to do is replace the engine with a more powerful unit, at resent it has a 16HP vanguard, does anyone on this site know of an easy swap unit and where to obtain at a good price, or what i am looking at for shaft and keyway size ect,,,, ?

Thanks

Neil

[Toys4Me]

Harbor Freight 22hp. Pull the 16, mount the 22 with all the old parts and enjoy. I love my max IV with the 22.

[howdah]

So it just a straight swap over ? Nothing else ? Maybe a feed for a fuel shut off solenoid ? Shaft and key way all the same ?

[Toys4Me]

It does have electric fuel solenoid. You will have to either build your own exhaust or modify the stock harbor freight to exit to the rear. As far as mounting, shafts, keys and clutch its rip and replace. Here is what I did for the exhaust. I like things on the louder side.

[howdah]

Looks like this will be the winner then , just reading the reviews of the engine and one said that the high idle speed was an issue with a centrifugal clutch and the adjustment is sealed , did you experience the same ?

Thanks for all the help on this !

[ARGOJIM]

I put one in an Argo (which is more speed sensitive) and it idles and shifts fine, adjust it a tad and you should be good.

[Toys4Me]

I run mine without a governor. The idle screw is under the air filter box. You remove the air filter and there is a plug you remove to access it. Mine idles at about 1100-1200. I have no problem shifting.