When i run my boat only a very small amount of water comes out of the hull. When i bring the boat in the engine is real hot,you cant put your finger on it for more than a second. Im afraid to keep it running for more than a couple of laps. The water pickup is on the rudder which goes through the head of the engine then through the header then out. When i blow water through with my mouth the water just dribbles out, not even at a steady stream. The whole boat is new so their are no restrictions. Should i lose the water cooled exhaust setup for more water flow through the head or try something different. Motor is an ops 67 inboard with a aeromarine rudder to pickup water. Thanks
- I was also thinking of adding an additional pickup fo the exhaust if i really need to cool it. Thus i would have separate cooling systems for the head and the exhaust

it may be new but you have an obstruction somewhere! check for a pinched nipple or casting bur. check check an re check! losing the header cooling will aleviate nothing

I would try your cooling flow test on different components to see where the restriction is. Try it on the rudder, on the engine, then on the header cooler. Once you figure out where the restriction is, you can decide what to do to fix it.

Sean

Checked several times for burs in the fittings, blocked lines etc... I ended up running it for a while with the exhaust coling bypassed. I got the water running through the head only and it shoots a heavy stream while running-the way it should. It seems as if the exhaust cooling is kind of restrictive. Should i run another water pickup for the exhaust cooling or can i do away with it? Question 2- Is their any way to get rid of cooked fuel on the motor head from priming it, its ugly looking and hard to get rid of.

What kind of exhaust plate do you have?

Compare the size of the water fittings. Maybe they are too small or smaller than whats in the head of your engine.

If you can, take the fittings off the plate and see if you have build-up. If it is a flat plate style after-cooler you should be able to see clear through it easy.

the fittings in the exhaust are the same as the fittings in the head. I took them out and checked the plate, everything looks brand new, no blocks or anything.

I would check the opening in the fittings with a paper clip and see if there are any burrs inside the holes that you can feel.

OPS fittings are kinda on the small size for the drilled hole diameter. Maybe new fittings with better hole diameters?

You may even be able to drill out the ones you have but if your not careful you could weaken the neck of the fitting, so you would have to measure the stem size and go with probably a number drill to get the right drill size going to stay with a good wall thickness.

The thread sizes that are in my OPS 45 are M4 for the fittings, I dont know if they are the same as yours. You can safely drill out the M4's up to a M5 size if you wanted to go that route too, but check to see if the hole size gets larger with the threads. There wouldn't be a point it doing that if it didn't. Sometimes the thread size changes but the hole size doesn't. Go figure.

That "Tough Racing" picture is one I had on my computer. Looks like nice stuff and they have other boat stuff too. Here's the [link=http://www.toughracing.com/]link[/link] to that and they even state the hole diameters on some. Not the M4's though, of course...

You might want to investigate into [link=http://www3.towerhobbies.com/cgi-bin/wti0095p?FVSEARCH=pressure+fitting&FVPROFIL=++]pressure fittings[/link] or [link=http://www3.towerhobbies.com/cgi-bin/wti0095p?FVPROFIL=&FVSEARCH=nipple]nipples[/link] at Tower Hobbies. You might find another brand that has the same thread size that has a bit more robust inside diameter.

Most descriptions dont have thread sizes though, so you would have to ask or write them to find out, or look into the manufacture's specs. One thing I do know is OPS is wimpy on the water fitting diameters for some reason.

Another thing to look out for too when you want good flow is staying away from 90 degree type fittings.

One thing I should mention also is the inside hole cant be any larger than the bottom root of the thread, so when looking at fittings, look for the ones that don't have an undercut at the end of the threads at the shoulder. This usually indicates the hole diameter is on the larger size, or if not can be drilled to very close the minor thread diameter. Don't be fooled by the barbed end looking large.

Look for the fitting with the hole as close to the same size as the bottom of the threads. Hard to do sometimes with just pictures though. I think this is the drawback of the OPS fittings. They undercut the thread clearance near the shoulder too much and it restricts how large they can drill the hole.

Good infrmation, i am gonna try and get that style fitting. They look like they flow better.

No problem. I just went through all this with a couple of my motors. Its good that you keep with the exhaust cooler though, it saves on couplings and I am sure it soaks quite a bit of heat off the exhaust port too.

I ended up drilling out the stock ops fittings today. I was able to open them up pretty good and still maintain strength. Pumps water like a champ now. Thanks

I have a water pick up on my boat works great you can see the water shooting out at the side got it on e bay lol