"Naval Architecture of Planing Hulls" by Lindsay Lord (c. 1946, 1954)

This book was the bible when Marinettes were first built, and was probably the reference used by the designers.

There is a copy on Amazon for only $200 (for a 300-page book!) so it is still well thought of. It is available online at http://www.ulib.org/

I finally too my boat out on its first shake down run. engines ran fine except for one small problem. The port engine (counter rotating) exhaust manifolds ran supper hot and steam was coming from the exhaust off the back of the boat. The starbord engine exhaust manifolds ran cool. We shut down and checked everything and started the engine back up. We then ran the engine at around 2500 rpm out of gear and the manifold cooled down. We then returned back to idle and put the port engine back in gear and ran the boat back up to around 2500 rpm. all seemed Ok until the small section of brand new exhaust hose on the port side of the port engine between the riser and the y melted out the bottom.

Any thoughts ?. Both water pump impellers are brand new and their is no leaks at the strainers. The strainers even have new gaskets. Everything is new except the exhaust manifolds, elbows and the risers.

Is it possible that both manifolds are somewhat blocked up ?. But if thats the case then why would it be just the port side and not the starbord engine as well ? These are the stock manifolds that came with the boat since it was built.

Both the manifolds and the risers was getting too hot to the touch but the engine ran cool enough not to overheat.

If I have to replace the manifolds and elbows and risers ... what company should I go with. Osco or Barr. Osco was what we always went with way back when I worked on boats for a living ....but that was a long time ago and quality has changed dramatically over the years.

Thanks Denis

The fact that your exhaust hose melted suggests that insufficient amounts of raw water are reaching that part of your system. That can be caused by restrictions in the manifolds, risers, elbows or cooling hose. Are you sure the new impellers are the correct ones? The impeller (09959) from the 1" raw water pump will fit into the 1-1/4" pump (G-7) but will not pump sufficient water at idle or at high RPMs. As Jeff says, don't ask me how I know this. The correct impeller for the Sherwood G-7 (1-14") raw water pump is 10615.

I did check water flow off the back of the boat and it looked the same as the other side. Impellers are the correct size for the pump. The water inlet is at the top (front) of the manifold and the outlet feeding the riser is coming off the top rear of the manifold.

I just pulled both manifolds off today and broke them down here at my shop. I really wont know anything till tomorrow when I take them to Greg's shop and put them in the media blasting oven and get them sparkling clean.

Because the water inlet is at the top of the manifold ...Im thinking AIR BUBBLE. I may re-plumb so that the water comes in from the rear of the manifold on the bottom and then feed the risers from the front top to eliminate the air pocket if indeed that's what is happening. First I want to make damm sure that all passages are clear and free from rust or debris and then do some water flow testing and see how things flow inside.

The manifolds look really good for being 30 years old but like I said....I wont know anything until I get them cleaned up and look around the inside with a bore scope to see how the water passages flow around the inside of the manifold.

my 440's

I broke down the manifolds, elbows and risers on both engines and found a ton of large rust scale plugging up the water passages on both engines. I took everything up to Gregs engines and we removed all the plugs and fittings and put the separate items in his 3 tier oven media blast system that made all the castings look like new again. I re-installed the manifolds after paying through the nose for new gaskets, o-rings and sleeves. I also re-plumed the water flow so that the water enters the bottom of the manifold at the rear of the engine and exits the top at the front of the engine so that theirs no chance of any air being trapped at the top. Now, the manifolds, elbows and risers run very cool and theirs twice the water flow coming out the exhaust. 2nd shake down cruise is planed for this coming Tuesday.

One of the marina services lost the steering bezel to the flybridge steering box so I now have a new problem. The steering system is a steermaster which is no longer made and I have to replace the entire steering system.
Has anyone here had to replace a dual station steering system on a 37 dcfb?. Anyway I look at it, its going to be a headache and expensive. I can go with a hynautic system or I can stay with a cable system. It comes down to what will retrofit the easiest. The last thing I want to do is open up Pandora Box trying to attach a hydraulic ram however the oil lines are easy to run but the entire system is stratospheric in price.
If I go with a new cable system the question then becomes "which one" and then I have to run all new mechanical steering cable which Ive done many times in my life and I can tell you it is the most exhausting job their is to do on a boat with a flybridge. Control cables are bad enough but new stiff steering cables are a damm nightmare. The last one I did was 25 plus years ago on a 31 chris craft flybridge for the guy that docked next to us and after that job I swore I would never do that job again.
Anyway I look at it, I'm in for a fight because I'm dealing with a dual helm system so the question now becomes which way to go.

Thanks Denis

Denis;
I had to replace my Steermaster cable, mechanical, and got a one from ( GLEN L Marine Designs ) Gave them a call and told them the # on the end of the beszel , its the lenght and had it in few days . No mounting change , everthing matched up perfectly. If you want to give them a call here's there #. 562-630-6258 . There web is, www.glen-l.com . I believe they have cable lenghts listed . If you don't want to go to hydraulic check them out. Got mine last year and can turn with one finger; one of the best $ moves i made.
Mark