One way water

[Phil]

I have a 1984 Cat 27 with a Universal M18 diesel. All the diagrams show the exhaust manifold making a loop upward before heading back toward the stern. A cooling water line meets the end of the manifold. There is no anti-siphoning device other than this loop in the manifold. On my boat, the manifold has been turned 90 degrees so that it no longer performs that function. I haven't had the boat too long, but the few times I have had minor difficulties starting up after a long sail have included following seas with modest pitching and rolling. Do you suppose it's possible that small amounts of water get by the flapper valve on the exhaust and make it back to the engine where it causes difficulty starting? In any case, how critical do you suppose it would be to correct this anomaly? Is it even possible that this installation is ok on certain models?

 

[DAve]

Exhaust Water

Phil: I have an atomic 4 in a CAT 27 and have had in the past water problems like you describe.....First off rotate the loop up....Should look like an inverted "U"..Then measure the forward vertical and the aft vertical. The forward vertical should be 3 inches higher than the aft one. If this is not the case...revise so that it is....You should have no problems after that...Also, Catalina sells a stainless flapper to put over you exhaust on the stern of the boat. This is helpful to have in following seas....Good luck...DAVE

 

[Phil]

Thanks

Thanks Dave.We went out last weekend. On Saturday it was choppy and brisk. The engine started without a problem at the dock and gave us quite a nervous fit on the return to port. On Sunday it was flat and calm and the engine started no problem at the dock and at several times while out during the day. I do have the flapper valve but it may not spring shut too well any more. I'm going to turn the manifold 90 degrees this weekend.On the same question, the manuals I have found on the web have the exhaust system depicted as I have on my boat. The actual manuals that I have (original from the boat as far as I know) show an aqualift muffler system with an anti-siphon valve. Do you know when Catalina started or stopped using this system? Did/does that system have more or fewer problems with water getting in the engine through the exhaust?

 

[Phil]

Thanks/Aqualift system question

Thanks Dave.We went out last weekend. On Saturday it was choppy and brisk. The engine started without a problem at the dock and gave us quite a nervous fit on the return to port. On Sunday it was flat and calm and the engine started no problem at the dock and at several times while out during the day. I do have the flapper valve but it may not spring shut too well any more. I'm going to turn the manifold 90 degrees this weekend.On the same question, the manuals I have found on the web have the exhaust system depicted as I have on my boat. The actual manuals that I have (original from the boat as far as I know) show an aqualift muffler system with an anti-siphon valve. Do you know when Catalina started or stopped using this system? Did/does that system have more or fewer problems with water getting in the engine through the exhaust?