Old Johnson startup questions

[cimmaronjim]

Bought a boat with a 1956 30hp RD-18<br />Hasn't run in a few years, Motor seems complete and isn't siezed. Would like to service the waterpump before I try to fire it up, but new water pumps for that year don't seem to be readily available. No problem getting an impellor though. Would replacing the impellor be enough of a service to try starting it or do I really need to replace the entire water pump assy? Or is replacing the impellor about all you need to do for a water pump service on this model?

 

[jegervais]

Re: Old Johnson startup questions

The complete water pump kit is p/n 379774 and any JohnnyRude dealer can order it for you. It should be a reasonably common kit, it fits several motors from '55 thru '73 or so. If you're not sure of the engine's maintenance history I would suggest the whole kit. Ignition coils on those have a tendancy to dry out and crack which renders them not runnable, so start the engine in a barrel of water before you attempt to take the boat out. Running the engine in a barrel should also clue you in to any potential carb issues too. The correct fuelil ratio is 24:1.<br /><br />-John

 

[cimmaronjim]

Re: Old Johnson startup questions

Thanks John, didn't know the w/p was a common part, just didn't see any listed anywhere. definately gonna run it in a barrel first, got it on a stand now. Thanks for the coil tip, will also check out the ignition system before starting. Motor has been converted to single hose system so will check out fuel pump too.<br />Everyone has been so helpful to me.<br />This board is tops!!!!!!!!!<br /><br />cimmaronjim

 

[rolmops]

Re: Old Johnson startup questions

Hello Cimmaronjim.<br />Thanks for the info for my paint job.<br />Normally the waterpump housing on these old engines is ok,unless they have been used in salt water and have not been cleaned afterwards.You should be able to find this out when you try to open the housing.If you have a real hard time loosening up the screws holding the housing you probably have sedimentation trouble inside as well.<br />The housings that are available have either one or two openings for the water pipes that come down from the engine.I think yours has one.<br />Good luck.

 

[cimmaronjim]

Re: Old Johnson startup questions

Thanks, Cap'n. I'll check it out