View Full Version : Johnson 70hp 2000

03-17-2007, 04:52 AM
"this is a twin 70 setup. I struggle to get them to run then when hot, they start but it is sporadic.
on the way home, stop in past the dealer, start first kick. only 70 hours on them?"

03-17-2007, 05:34 AM
"Be sure You do not use choke/prime when starting them hot, just cranck."

03-17-2007, 09:29 AM
"idle speed may be set way low..when u are trying to start,u are at lake,at dealer,..my guess is it is on a hose,no exhaust back pressure.U might try idling them up a bit."

03-17-2007, 04:49 PM
"David, I had experience with a 2000 Johnson 70 that behaved as you describe. We knew it was vapor locking, but we didn't know why until I took it out on a WOT run and found it seriously overpropped and probably running hotter than it should because of the excess load. I would make sure you are propped near the top of the operating range, and that the impellers, t-stats, and pressure valves are clean and in good condition.