In the absence of an ilawnmowers forum, I thought I'd throw this question to you folks.
My 13 year old Scotts gas powered lawnmower suddenly lost compression after using it a few months ago and wouldn't restart. At 13 years old, it doesn't really owe me anything, but if I can avoid spending $300.00 on a replacement, I will.
I removed the cylinder head on the engine (tecumseh) and found that one of the valve seats (exhaust valve) had decided to uproot itself from its machined seat in the aluminum cylinder head. The valve seat I guess is steel or something similar. The inlet valve seat by comparison is fine.
My first repair attempt was to clean the head up and put the valve seat in the freezer. Next day, I placed the seat back in its machined place in the head, tapping it in with a socket of the same diameter for good measure. The theory was the frozen seat would be smaller than the machined seat and would fit in easily, warm up and snug tightly inside the machined seat. After reassembling the mower fired up first time and ran like a hero - for 3 mowings! It then did the same thing again.
For my second repair attempt I stripped it down again and this time replaced the valve seat and then using a small counterpounch 'peened' over some of the aluminum on top of the seat to hold it in place (I found that tip on the internet). Again, the mower worked fine for 3 more mowings and then did its thing again.
My mind then moved to 'glue'. I checked out Loctite Epoxy 5 minute Set adhesive, which claims many things including being heatproof to over 300 degrees F, so for a few bucks I thought I'd give it a try. So that's what I did this weekend for my 3rd attempt and it lasted just 1 mowing. So much for LocLoose, sets in 5, lasts just 5 adhesive!!
So here I am at a crossroads. I checked out small engine parts and I can get a new cylinder head complete with valves, etc for about $100.00 incl S&H. But I can't bring myself to spend that amount of money on this 13 year old mower. I've thought about taking it to a lawnmower repair place and have them fit a new seat. I understand they would have to machine out the existing seat space to accept a large valve seat, then presumably grind out the new seat, etc, etc. That all translates into more than $100.00 IMHO.:deadhorse:
The other alternative is I have it put down and buy a new mower.
Anyone got any 'lightbulb' suggestions on making a reasonably permanent repair on this thing?
My 13 year old Scotts gas powered lawnmower suddenly lost compression after using it a few months ago and wouldn't restart. At 13 years old, it doesn't really owe me anything, but if I can avoid spending $300.00 on a replacement, I will.
I removed the cylinder head on the engine (tecumseh) and found that one of the valve seats (exhaust valve) had decided to uproot itself from its machined seat in the aluminum cylinder head. The valve seat I guess is steel or something similar. The inlet valve seat by comparison is fine.
My first repair attempt was to clean the head up and put the valve seat in the freezer. Next day, I placed the seat back in its machined place in the head, tapping it in with a socket of the same diameter for good measure. The theory was the frozen seat would be smaller than the machined seat and would fit in easily, warm up and snug tightly inside the machined seat. After reassembling the mower fired up first time and ran like a hero - for 3 mowings! It then did the same thing again.
For my second repair attempt I stripped it down again and this time replaced the valve seat and then using a small counterpounch 'peened' over some of the aluminum on top of the seat to hold it in place (I found that tip on the internet). Again, the mower worked fine for 3 more mowings and then did its thing again.
My mind then moved to 'glue'. I checked out Loctite Epoxy 5 minute Set adhesive, which claims many things including being heatproof to over 300 degrees F, so for a few bucks I thought I'd give it a try. So that's what I did this weekend for my 3rd attempt and it lasted just 1 mowing. So much for LocLoose, sets in 5, lasts just 5 adhesive!!
So here I am at a crossroads. I checked out small engine parts and I can get a new cylinder head complete with valves, etc for about $100.00 incl S&H. But I can't bring myself to spend that amount of money on this 13 year old mower. I've thought about taking it to a lawnmower repair place and have them fit a new seat. I understand they would have to machine out the existing seat space to accept a large valve seat, then presumably grind out the new seat, etc, etc. That all translates into more than $100.00 IMHO.:deadhorse:
The other alternative is I have it put down and buy a new mower.
Anyone got any 'lightbulb' suggestions on making a reasonably permanent repair on this thing?
