Lowboy question
- Thread starter ctltmp
- Start date
Bigwally30
Active member
Check fuel flow at carb, check spark , and check compression. One step at a time.
The engine may need a tune up, and the points filed flat, or replaced, they need to have the right gap, .020" for the Battery Ignition unit. Wipe off all filings with a clean rag.
The timing should be checked with a timing light. If it is set wrong, the power can be less than it should be.
Here is info for doing a compression test, if you need it.
Be sure the LoBoy doesn't roll when doing the compression test.
Open the throttle fully to do the compression test, so the engine can get air.
Have all 4 spark plugs out of the engine at the same time.
Clean all dirt from around the spark plug bases, so the dirt doesn't fall into the engine.
You don't have to remove the hood to get to the spark plugs. I work up under the hood. Wear gloves, and a thick shirt to protect your hands and arms.
You can sit on a lawn chair on the left side of the LoBoy to work there.
Move the Touch Control arms to the rear or down position, and there is more room to get to the rear area of the engine head.
Charge the battery fully before the test, and use the starter.
Charge a new battery also, they are not always fully charged, a low output charger is better, 6 amps or so, that automatically goes down as the battery charges. It may take several hours to charge.
The Cub and LoBoy service manual says a LoBoy engine should have 120 lbs of compression, when turning at 240 RPM. That is probably for a new engine.
Some less is ok, they have said on here 90 lbs or above is ok.
I write down the results, so I have a record.
The timing should be checked with a timing light. If it is set wrong, the power can be less than it should be.
Here is info for doing a compression test, if you need it.
Be sure the LoBoy doesn't roll when doing the compression test.
Open the throttle fully to do the compression test, so the engine can get air.
Have all 4 spark plugs out of the engine at the same time.
Clean all dirt from around the spark plug bases, so the dirt doesn't fall into the engine.
You don't have to remove the hood to get to the spark plugs. I work up under the hood. Wear gloves, and a thick shirt to protect your hands and arms.
You can sit on a lawn chair on the left side of the LoBoy to work there.
Move the Touch Control arms to the rear or down position, and there is more room to get to the rear area of the engine head.
Charge the battery fully before the test, and use the starter.
Charge a new battery also, they are not always fully charged, a low output charger is better, 6 amps or so, that automatically goes down as the battery charges. It may take several hours to charge.
The Cub and LoBoy service manual says a LoBoy engine should have 120 lbs of compression, when turning at 240 RPM. That is probably for a new engine.
Some less is ok, they have said on here 90 lbs or above is ok.
I write down the results, so I have a record.
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