cobra525

My Feedback: (5)

Hello,

A curiosity question here.

Just bought a used Saito 120s that seems to be in very good shape. It has great compression. However when I got home and compared it to the Saito 100, the 100 seems to have more compression when turning them by hand. Is that normal? I would think a 120 would be harder to turn than a 100 shouldnt it? I checked the valve clearance and all case screws for tighness and found nothing bad. Its pretty saturated in Marvel Mystery Oil, could that be making it easier to turn?

speedster 1919

My Feedback: (3)

The key word here is " USED " An engine may look great outside and have a worn ring and scored cylinder wall. Then again the ring could be partially stuck from storage. I wouldn't make judgement till you bench run a couple of tanks thru it.............

aussiesteve

Also make sure that the throttle is open when you're checking it by hand. A closed throttle will give the appearance of very low compression on some of the engines.

w8ye

My Feedback: (16)

Put the same oil in your 100 as your 120S and compare?

NM2K

My Feedback: (14)

And don't forget that the 1.00 is really a 1.10.


Ed Cregger

cobra525

My Feedback: (5)

Well, thanks for the feedback. I hate buying used motors and maybe just paranoid. Thinking about it, the oil should only give more compression if anything. speedster is right I will just run it and see.