Any way to FWC my manifold?

[TwoBallScrewBall]

3.0L OMC, is there any way to add the manifold in the FWC circuit? My manifold only has one endcap on the front, where the raw water from the heat exchanger dumps in, through the manifold, and out the exhaust. Is there any way to block off the manifold at the elbow, then route the fresh water from the engine through the manifold then back to the exchanger instead of straight to the exchanger? The problem would be adding a return line exiting the manifold. Anyone know of a way? Could I drill and tap the manifold for a fitting, perhaps enlarge the existing drain plug fitting? I could then route the raw water out the transom in a bilge pump-type manner. <br /><br />Thanks!!

 

[FreeBeeTony]

Re: Any way to FWC my manifold?

Is this an IL4 engine? I did what you want to do with an additional end cap.

 

[yoced]

Re: Any way to FWC my manifold?

Um, yes it can be done. Drilling and tapping like you said.<br /><br />I would not recommend it to _my_ customers. I have seen way too many problems at the end of that project. <br /><br />Long and short of it is that if the project does not turn out the way you want there is no arse but yours on the line.<br /><br />No manifold manufacturer will warrant their part once you start drilling and tapping. OMC did not fresh water cool that manifold, and neither did the aftermarket companies. And none of them would stand behind you once you start this type of project.

 

[Bondo]

Re: Any way to FWC my manifold?

huminski,<br />IF your OMC manifold Has the Holes for it,<br />You can do like FreeBeeTony has done(even thou he has a few bugs, I'm Confident it'll work out)......<br />The Merc. manifold Has a plate, where the Extra Nipple was needed........<br />Tony will Hopefully repost the photos of his project........<br />He didn't plumb it the way I envisioned it,<br />But, It Should Work,... Just Fine.......

 

[TwoBallScrewBall]

Re: Any way to FWC my manifold?

That's the thing, I have the newer style manifold on my 3.0, with only one removable plate on the front end. The rear end is curved and exits directly into the riser. Like this:<br /><br />

<br /><br />Look closely, and near the bottom right side of the manifold you can see the drain plug. I was thinking of drilling this out and tapping it for a larger hose fitting, similar in size to the one on the front plate. Actually, I would probably ask the guy down the street from me with a machine shop to do the drilling and tapping. <br /><br />I would also cut a plate between the riser and manifold to block off the water passages.<br /><br />I am worried about the exhaust temp and cooling capacity.... <br /><br />1) Will this heat the coolant to the point that the heat exchanger won't be able to sufficiently cool it? <br /><br />and<br /><br />2) Will there be any problems with the heat of the exhaust gas now going down the J-pipe and out the outdrive without water?<br /><br />Tony, what are the bugs that bondo's talking about? How is your system working?<br /><br />Let me know! I saw what my old raw-water cooled manifold looked like inside and want to avoid that with this FWC idea.....

 

[Bondo]

Re: Any way to FWC my manifold?

1) Will this heat the coolant to the point that the heat exchanger won't be able to sufficiently cool it?

The Idea is to have a H/E that's Big Enough......<br />

2) Will there be any problems with the heat of the exhaust gas now going down the J-pipe and out the outdrive without water?

You Have to Dump the Raw Water back Into the Riser.......<br />The Exhaust is Still Wet..... Same as it Was.....

 

[TwoBallScrewBall]

Re: Any way to FWC my manifold?

I think maybe I'll just keep flushing it well after I run it, don't know if it would be worth the trouble the more I think about it...... Thanks guys!