water pressure -omc 115 seadrive

[masondr]

What is acceptable water pressure for an Evin/Johnson Omc Seadrive? Seadrive is long shaft, but I have been told that powerhead is same as Evin/johnson regular outboards. Have 3Psi at idle, and 8-10 at wide open. Waterpump rebuild had no change. If this is too low, where should I look for cause? Does not overheat.

 

[Pursuit2150]

Re: water pressure -omc 115 seadrive

My B-Inlaw,has a seadrive, and I was always suprised at the low water pressure he had, He has run it hard, never had any overheat probs. I think it is just common on that model.I never saw the gauge go over 8PSI.

 

[its-a-sweater]

Re: water pressure -omc 115 seadrive

Dave,<br /><br />I've noticed similar on OMC V-4's. The ones I've run never had much more than that.<br /><br />Has it changed?

 

[DJ]

Re: water pressure -omc 115 seadrive

It's really a function of where the cooling system is tapped into. Most water pressure guages on OMC's are tapped into the block drain. This is the last point in the cooling system before the water exits the engine.<br /><br />Also, the exit orifice can erode over time thus, in effect, opening the size of the orifice-less pressure read.<br /><br />It has been my experience that OMC V-4's do not create a great deal of pressure. Flow is more important than pressure. The pressure guage is just an early warning indicator.<br /><br />On some of my previous rigs I have hooked up an LED light to signal when the psi. dropped below five. I used an automotive adjustable oil pressure switch. They're available at speed shops. I did this after I blew a head gasket because I wasn't watching the guage that was sitting on zero. My fault. <br /><br />You could also rig up a light in leau of a gauge. Some of the high end bass boats and flats boats have this feature. It is helpful for engines that are trimmed high for clearance (flats) or speed (bass).

 

[masondr]

Re: water pressure -omc 115 seadrive

Pursuit2150/Its a sweater/djohns19: Thanks for replies. one thing I forgot to mention-thermostats and springs were removed from motor some time back.Local thinking on this, especially for salt water use, is to do without them to avoid problems with sticking from salt corrosion. From another posting, it sounds like this may not be such a good idea. Could this have reduced pressure some?I was'nt checking pressure at that time.