Re: 1971 Mercruiser 3.0L Wiring Diagram or Service Manual
just an update... stuck some Marvel mystery Oil in the cylinders, let it sit for a couple of weeks, due to me being busy, but i cleaned the marvel out, then re-checke4d the compression, pulled them up had Cyl 1) 140 psi, 2) 140 psi, 3) 120 psi, 4) 90 psi. I talked with a fried of the family who has been a mechainc for the past 30 years or so and he told me how to bypass the ballast resistor and the key if need be, so i did those, and the baby cranked right up. Hasn't been run probably since 1992 (before i even got it) got it to run, going to pickup a new thermostat for it, and changed out the lower unit fluid. But on the happy side of things, i got it running, let it run for a little bit, i got her to idle all the way down to 400 rpms which i was soo happy i just about pooped myself, and then re-checked compression and now they go as cyl 1) 145 psi cyl 2) 145 psi cyl 3) 140 psi cyl 4) 125 psi, the last is a little low but according to the guide 20 psi difference is the "ok" limit for compression. Should be going for a water test soon, need to still put the floor in.
just an update... stuck some Marvel mystery Oil in the cylinders, let it sit for a couple of weeks, due to me being busy, but i cleaned the marvel out, then re-checke4d the compression, pulled them up had Cyl 1) 140 psi, 2) 140 psi, 3) 120 psi, 4) 90 psi. I talked with a fried of the family who has been a mechainc for the past 30 years or so and he told me how to bypass the ballast resistor and the key if need be, so i did those, and the baby cranked right up. Hasn't been run probably since 1992 (before i even got it) got it to run, going to pickup a new thermostat for it, and changed out the lower unit fluid. But on the happy side of things, i got it running, let it run for a little bit, i got her to idle all the way down to 400 rpms which i was soo happy i just about pooped myself, and then re-checked compression and now they go as cyl 1) 145 psi cyl 2) 145 psi cyl 3) 140 psi cyl 4) 125 psi, the last is a little low but according to the guide 20 psi difference is the "ok" limit for compression. Should be going for a water test soon, need to still put the floor in.