CMB LS / Lawless eating shafts

[magsden]

HTB 290 with CMB LS and Lawless with Strongarm shafts. I grease the shafts with Mercury outboard grease after every heat and I only get about two heats before the shaft looks like it is starting to spin near the prop end. Is there something else I should be doing beside buying caselots of these shafts? I haven't dared to try a K&B shaft in there. May not make a heat. :huh: :huh: :huh:

 

[jydracing]

hi magsden here is a way to fix the problem. i had the same problem with mine. what you need to do is take the lowerunit apart and where the flex shaft tube is resting aganst the lip behind the prop shaft there is your problem. the flex shaft is rubbing the lip and when it gets hot it takes the tempering out of the shaft and breaks. to fix it gring the lip out compleatly the flex shaft tube will not move at all so do not worry.than put it back togather and have fun. if you are breaking shafts in the middle than you need to go to a smaller prop or raise your engine. hope this helps jimmy

Ps get off of the grease use stp engine treatment and 30 wt engine oil in a 50/50 mix the grease will not penatrate the shaft and it will let it rust and break

 

[magsden]

Thanks jdyracing, I'll get to that tonight. Gettin' to be a real pain replacing those shafts. I'll try the oil thing. You just fill from the top before each run? Do you plug the holes at the bottom to keep it in?

 

[jydracing]

no i do not cover the holes i pump it in until it runs out than run the boat i oil the shaft before each run.

 

[dave roach]

If you are braking shafts and check the prop shaft to see if you have a lot of play in it .and check your prop for balance.I have been running the lawless lower unit for three years and have"nt broken a shaft. I use stp and 90 weight gear lube mixed 50/50. I give it a shot every run.try this and give use a report back.

Dave Roach

 

[magsden]

Thanks Dave. Iwill check the prop shaft. The prop was purchased as balanced and I haven't bought a balancer yet. Hope that is not the problem. Guess I better get one of them thar balancin' widgets too!!! Wife don't understand all the whys and whatfors of this stuff. Just haf ta say cuz I need it thats why.

 

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Magsden,

I have had some similar problems but it was more like the cable unwinding and stretching. also I was breaking prop shaft assemblies left and right, it was getting expensive.

 

[aamick1971]

man sounds like a pain in the butt,ihaven't had those problems. with my lawless the problem i have i have cutt off about an 1/8" of the flex shaft to get it to fit k&b and the lawless shafts.also i did what fred @lawless told me to drill out the k&b prop shaft but i still have to cut some off ,but havent broke one.

thanks,

allen