Re: Potential Lawn-Boy tweaks - hand-lap reed, double crank seals, crankcase stuffing
Yes I think you could install the thrust bearing and washer(s) in yours without modifications. Just based on the amount of wear you said you have there should be room, and then some...might have to add multiple washers.
In regards to the question about what would cause the wear in the lower crankcase; I'm not real sure, but I tend to think it's a couple of issues. The first being just dirt, grit getting into the crankcase and mixing with the oil and depositing in the bottom where it acts like a grinding compound and will fairly quickly wear the soft cast aluminum crankcase cover assembly. I've had problems with dirt bypassing these F series rectangular air filters in real harsh conditions, for me it happens real early in the season when I'm scalping the dormant grass. I really think a remote air filter is the way to go for F series use in harsh conditions, and yes I have one on my wish list.
Secondly, I have noticed that all these instances where folks have reported excess vertical crank play it has been self-propel engines. This would indicate to me that the belts might not be aligned perfectly and kinda pulling the crank down. In the case of the worm gear drive cranks it is pretty obvious that when you have angled gears you are going to have the crank being pushed up, or down vertically as it's rotating. Nothing scientific here, just my 2 cents worth.
Now the question I have been asking myself for the last couple of years is why I only have air filter bypassing on the rectangular F series and nothing even close to that with the old round D-400s? I run these old small round D-400s where it's gets pretty thick with grass/ debris on the outside and I'm thinking to myself that I hope none of this debris bypassed the filter, and after a quick removal for cleaning, or exchange for a clean one, I notice that it's perfectly clean on the inside of the filter, just like it should be.
Edit: If you want I would like to donate a thrust bearing and washer out of an old engine from a 10401. I don't think I'll need them since all my mowers are pushers and the vertical play just doesn't seem to be a factor with them anyway, furthermore I'd like to see if fits, and if it does great! and it's yours free of charge, if it doesn't fit, you won't have wasted any money. Let me know and if it's a go, I'll go out and dig them out of the shed. Hopefully still have them.
Last edited by Lawnboy77; 06-29-2019 at 03:14 PM.