Loss of power

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Royalwulff24
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Zip Code: 16844

Loss of power

Postby Royalwulff24 » Sat Sep 10, 2022 4:47 pm

Hi guys I have a 59 cub, it's ran fine since I purchased it 7 years ago, while trying to push a little bit of dirt around, as soon as if came under the slightest load it lost power, I took it back to the garage, started by adjusting the valves, out cover back on, started it, it ran noticably smoother, I tried it again, no power, brought it back, brought it to TDC, set the points, hooked up timing light, set it at 16° btdc at full throttle, throttled down to low idle and pointer was just shy of being at TDC mark. Then pulled all plugs, did compression test, I got 80lbs in all cylinders give or take a pound, haven't tried it since doing that because it's raining, but I'm curious if I missed anything and what the next step would be ? Also, as soon as it came under a load, the air intake was making a funny sound I'd never heard before, kinda like playing cards in your bicycle spokes, if anyone remembers that...lol. Thanks in advance.

tst
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Re: Loss of power

Postby tst » Sat Sep 10, 2022 5:25 pm

80 lbs is pretty low for compression, take the air cleaner hose to the carb and run it, make sure that way you do not have a dead squirrel or something making it air starved, what did you adjust the valves too ? should be about 14-15 thou to tight will cause more grief

Royalwulff24
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Re: Loss of power

Postby Royalwulff24 » Sat Sep 10, 2022 5:39 pm

My buddy just stopped by in his service truck, we tried his compression tester, and got 95 in 1-2-4, 92 in 3,I cleaned air cleaner, return line, everything is clean, I adjusted the valves to 15, it just started this loss of power thing , I did the exact same thing with it a couple months ago and it was fine, then it started with the weird noise from the air cleaner and loss of power, seems almost like it's loaded up or choke is on, with no load it hums like a singer sewing machine, governor maybe ? I just replaced a motor in a Hitachi track hoe, but it's diesel ,. So it's a horse of a different color and I haven't fooled with points since I crashed my 70 Chevelle in 1980 just want to make sure I'm dotting my I's and crossing my T's.

tst
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Joined: Tue Jan 12, 2010 2:08 pm
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Re: Loss of power

Postby tst » Sat Sep 10, 2022 5:51 pm

is the main jet on the carb plugged up

Jim Becker
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Re: Loss of power

Postby Jim Becker » Sat Sep 10, 2022 8:17 pm

You have a good hot spark at the plugs?
Check the choke arm on the carburetor that it hasn't slipped. Maybe you do have the choke on.
Beyond that, I'd next check the governor behavior.

Royalwulff24
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Posts: 18
Joined: Sun Dec 17, 2017 5:44 pm
Zip Code: 16844

Re: Loss of power

Postby Royalwulff24 » Sat Sep 10, 2022 11:16 pm

No the choke is open, but when I put #1 on TDC, the points were closed, is that right ?

Jim Becker
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Re: Loss of power

Postby Jim Becker » Sat Sep 10, 2022 11:42 pm

The points should be closed as you approach TDC and open just as you reach that point.

Gary Dotson
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Re: Loss of power

Postby Gary Dotson » Sun Sep 11, 2022 6:08 am

You mentioned that you set your point gap while at tdc, if so, that was wrong, they need to be adjusted when the rub block is on the highest part of the cam lobe.

Larry in WNY
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Re: Loss of power

Postby Larry in WNY » Sun Sep 18, 2022 6:42 pm

Running good at idle but not under load could be a governor problem . Verify the front governor spring isn't broken.


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