Tec HS50 versus H35 Power Sport

[Fisher1983]

So...I'm in the process of building my HS50 5hp engine. I have seen that the OHH50 billet rod fits the HS50. Today I acquired an H35 Power Sport 3.5hp and opened it up. I realized that the crank cases for both engines are identical. In fact, the side cover gasket I bought for the 50 is the same part number as the 35. The HS50 has a much bigger jug to house the huge piston, but the lower halves are the same. That being said....shouldn't the same billet rod fit the H35 Power Sport? The cranks appear to be the same. I had read before that someone had to clearance the block on an H35 for the billet rod dipper to fit. Perhaps this was an earlier H35 with different architecture? If the billet rod fits the Power Sport, I may have opened up a can of small block whoop ass. I always liked the little PS H35's....

 

[markus]

If you look at the front of the crankcase of both your engines you will see that the H engine does not have a humped area in the upper right side like the HS does, this prevents fitment of an aftermarket billet rod in the post 1984 H engines with the angled cap rod (HS connecting rod), as far as I know they never added the hump on the H, but the newest one I have ever had was a 2000. I tried an old stock Billet rod made specifically for an HS and it would not clear in the H case unfortunatly, and I believe that another member literally cut the case open to clearance for an ARC OHV rod to fit in a late model H.

I like those late model H engines too, They made an "H40" one as well. In the last spec sheets its shown as having only a ball bearing sidecover/crank as a difference from the H35.....I guess that bearing gives you an extra .5hp :thumbsup:

 

[Fisher1983]

Thanks for replying. I did notice a humped area in my HS50 block. I did not look for that in the H35. Its already back together and running. I did some reading after I posted this and saw the thread where a member windowed and tig welded his H35 block. Very cool but not for me LOL!