Changing on '70's 7.6hp
- Thread starter jcobo
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RichardTX
Silver Member
My advice is to forget it assuming you mean a 16hp single cylinder cast iron block Kohler. I had a SC here that needed to be repowered. By the time I got the correct gears for a modern high speed engine (3600 RPM vs the 2400 RPM Gravely engine) buy a used hi-low planetary, rebuild the planetary, and then get the adapter plates, etc, I could have bought a nice Pro16. So that is exactly what I did. I sold the SC for $50. I got the Pro16 with a two cylinder Briggs. The twin cylinder engines are easier on planetary gears that the single cylinder engines. The twin is lighter and thus a lot easier to handle than that heavy Kohler single. If my advice does not convince you, borrow a 5665, hang another 30 lbs on the rear hitch and then try to use it with a 30" mower on the front.
Your advice will be followed, thanks for the input.
I bought my 7.6 for $50.00, do you have relatives in southern Alberta?
John
Life is too short to learn everything yourself, ask others to help.
"He who asks a question is a fool for five minutes; he who does not ask a question remains a fool forever." -Chinese Proverb
RichardTX
Silver Member
Your advice will be followed, thanks for the input.
I bought my 7.6 for $50.00, do you have relatives in southern Alberta?
John
I have no relatives in Canada.
For $50 it would make for a good parts donor. What exactly is wrong with the original engine? Just burning oil? If you want to try a cheap fix for burning oil, just hone the cylinder and put in a set of rings. In a perfect world, just the rings wear and indeed that does happen occasionally. In that engine it is common for both the cylinder and rings to wear but just replacing rings will usually take care of oil burning. A re-ring won't last as long as a proper boring, honing, etc, but it usually is enough to get another year or 3 out of it.
There is one thing more. Putting a modern 3600 RPM engine on without changing the planetary is OK to do, but the new engine should be governed down to 2400 RPM. What that means is that the 12 hp engine that you buy will have reduced horsepower at that speed. A 16 hp Briggs Vanguard for example will only produce about 12 HP at 2400 RPM.
The basic Gravely tractor can handle at least 16 hp without issue. I once considered putting a 23 hp engine on a two wheel Gravely (5000 series). I might still do that just for the heck of it.
Having said all that, I would NOT put an engine on a 7.6. A Pro or a 5000 series yes, but not a SC or a L. There is just too much fabrication involved. My advice is to find a clean 5665. The 5665 was one of the most popular two wheel tractors that Gravely made.
Depending on attachments, condition and location, a running 5665 usually sells for $300 on up. I bought a Pro8 with sulky and 30" mower for $300 and all it needed was a battery and a carb cleaning.
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>With harvest just starting there should not be a lot of trouble selling the 16 Hp for a grain elevator.
Once again thanks for sharing your knowledge and experience.>
John
"Live as if you were to die tomorrow. Learn as if you were to live forever." -Mahatma Gandhi
RichardTX
Silver Member
BTW, changing the planetary is a 5 second job once the engine is off.
