Re: CD-11’s compression issue

[skanders01]

I am grateful for all of the input I have received here. Believe me, I thought long and hard before posting such an improbable situation. Seems as strange to me as to everyone else who responded and probably read for that matter. Here are some answers to the posted questions…
1. Not pulling anyone’s leg. I am truly struggling with this issue.
2. I have put several gages on the compression tester. and verified the compression test gage accuracy against several gages. The bleed valve holds pressure. I acquired a 1972 Johnson 40 HP with a boat I bought to mount three of my 5.5’s on. The compression test read 60 PSI on moth this motors cylinders. All this done, I will still buy and test with another compression gage to verify. Also hooked up the compression tester to my air compressor and it tested out in sync with the various pressures (compressor gage) I cycled it through.
3. Measured all cylinders compression prior to breakdown for rebuild. All were in this 30-35 PSI range. Also miced/measured all cylinder bores and pistons prior to rebuilding. All were not too far out of spec.
4. All compression tests (and starting attempts) were done using a cordless drill on low speed spinning the crankshaft.
5. The motor powerhead with the oil return head was different from the other three and I don’t know why. New oil return lines are new and on the opposite side on the others.
6. Can highly recommend a resource for Johnson "Sea Horse Green" if anyone is interested. PM me…
7. In hindsight wished I would have resolved compression issues prior to rebuild and cosmetics as well.
8. Honed them with a newly purchased ball hone. Seemed to work well. If anyone needs one for a +/- 2" cylinder this lightly used one with significant life left is available reasonably. PM me. Need to find $ for new powerhead! 😆
9. All shock absorbers were fine.
10. Backward piston installation is an interesting thought….even though I do know which is the correct orientation….can’t hurt to check; not beyond making a mistake or three.
11. To all of the "they should not even start/run" comments, two of the three I actually did total teardown/rebuild on won’t/don’t. The fourth motor I have ran and still runs fine, just went through cosmetic restoration on that one. The rub here is that it tests out at the 30-35 PSI range.
12. Believe me, I won’t be tearing these down before I solve this mystery.

I can’t begin to thank everyone for replying/commenting in an attempt to assist. Need all of it I can get! As long as you all will keep replyin I’ll keep tryin. I’ll update soon.

Regards,

Kyle Anderson
Trempeleau, WI
skanders@triwest.net
920-764-0501