Hi, I have a older early 1970"s Chrysler 120 HP. It runs good in the drive way and appears to have all the R.P.M"s but as soon as I put it in the water under load it will only get 1/4 throttle and I press on for more it boggs down,so I have to let up on it.....it idles aruond just great! LOL any ideas on whats the problem? I belive it has to do something with a fuel problem.I have put new gas in it already. Still the same.the model is #1207 HD thank you for any help Chuck