Very frustrated with D-engine mower
- Thread starter Phototone
- Start date
Thats next. Stand by
Test it this way. Use no oil or any lube just dry with only the oil left over from the last time it was run. Note reading on the first pull, then pull 3 more times note this reading , then pull until needle stops rising and note the last reading. I should have asked this first, What is the model and serial numbers?
IT WORKS!
Compression reading was 70lbs According to book, thats good! (that with new rings that may not be seated yet)
I put new spark plug in, poured some raw gas down carb, and it fired up just fine.
Now to mow a yard....the real test.
Compression reading was 70lbs According to book, thats good! (that with new rings that may not be seated yet)
I put new spark plug in, poured some raw gas down carb, and it fired up just fine.
Now to mow a yard....the real test.
Well, I had to use some assembly lube, to insert the piston back into the cylinder. So the assembly is oily.
See above, the mower works now.
I get a maximum compression reading (this was before it ran first time) of 70 lbs, according to Lawnboy Service manual this is OK.
The Mower is an International Harvester (made by Lawnboy)...has a D-600 series engine.
The compression reading at the time of assembly prior to being run may be a false reading. Only after running and washing out the assembly lube and testing on a cold motor will you get a true reading. The actual reading after having run the motor may be border line and is lower than 70lbs. If you have been using starting fluid to get it running you may have washed the oil off of the rings and lowered your compression below the minimum 65lbs required to run. And then by adding fuel / oil mix you then relubed the rings and cyl walls restoring the compression high enough to run. Wait until tomorrow with a cold motor and retest the compression. What is your spark plug gap and spark plug number and brand?
Its running now, very strong, and starts on first pull every time when warm. I have an issue with the primer not priming, but I have the parts to fix that. I did not use "starting fluid" when I was testing yesterday, rather, I used WD-40-which I generically called "starting fluid", which works quite well as starting fluid generally, and is oily, so it doesn't wash the cylinder walls down. MY problem was (I think) an old spark plug that got oily from the assembly lube (which I replaced with a fresh plug), and primer not working. Poured a little gas down the carb after putting in fresh spark plug, and it started right up, and ran. I just mowed a big yard. excellent performance.
Photo, Glad your'e running. Two stroke did mention an important topic-crankcase pressure. Maybe he will say more for 2 strokers watching, like the test gear used to test crankcase pressure.
Two stroke. Weak sparks get weaker at hot as the transistors miss there and improve a little at cold. But they cannot heal themselves like a semi-gummed carb. :smile:
Two stroke. Weak sparks get weaker at hot as the transistors miss there and improve a little at cold. But they cannot heal themselves like a semi-gummed carb. :smile:
Two-Stroke
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I know those insturments exist but I don't have one. :ashamed:
Here's what I do: Disconnect the sparkplug wire (for safety) but leave the plug in. Lift the mower up on its side and rotate the crankshaft by hand -- and observe carefully the feel of both the upstroke and the downstroke (relevant to crankcase pressure). If I'm familiar with what a good-running engine of the same series feels like I can tell if the suspect engine is OK -- within a reasonable margin of error. I've worked on quite a few D-series and F-series LBs so I know what they should feel like.
robinb66
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how bout the gasket between the carb and reedplate?