33FBC Exhaust

kwinters · Post by **kwinters** » Tue Sep 01, 2009 10:55 am

Anyone replace the rear/side exhaust on a 33 gas 454 with straight rear exhaust? My concern is following or backdown hydralocking of the engine if straight mufflers are used without the side exhaust. Comments please.

Post by **dougl33** » Tue Sep 01, 2009 11:35 am

Welcome aboard. I don't think anyone has done that yet. What do you think would be the benefit of doing such a conversion?

kwinters · Post by **kwinters** » Tue Sep 01, 2009 2:39 pm

The glass elbows are cracked and the bond between them is rotted out. I sometimes have oil or stains running down them. My glass guys are trying to come up with a clean solution since she is in drydock replacing the fuel tank which cracked in 2 places running to the Bahamas last month. Also, the fireboy sniffer never picked up the fumes, less than a year old. Just some side info.

lobsta1 · Post by **lobsta1** » Tue Sep 01, 2009 3:35 pm

Welcome! What's your name & what year is your FBC? Is that the original tank or a replacement? If replacement, what material? If it is metal, I was told by my tank fabricator that the tank is subject to failure if hard bolted through flanges. If original, I think you have the distinction of having the only tank that has ever cracked. Al

kwinters · Post by **kwinters** » Wed Sep 02, 2009 4:44 am

"Crews Inn". 1977. It is the orgional fiberglass tank. It cracked where the side gussets are glassed into the side of the tank on each side and the gussets glass to the stringers. I hit a wake from a 60+ sportfish who crossed in front of me. I was doing about 20 knots and he was doing 10 on one engine. It appears the tank tried to move forward as all of the resin holding it in the front and onto the rear bulkhead seperated in one peice as well.

otf · Post by **otf** » Wed Sep 02, 2009 4:15 pm

Wow, it takes a lot to get that tank loose. It's solid, at least it was in 83.

IRGuy · Post by **IRGuy** » Wed Sep 02, 2009 4:54 pm

If the glass elbows are the transitions from the round exhaust to the rectangular outlets on the aft hull sides just before the transom (affectionally known here as the "mail slots") mine were also separated and leaking exhaust into the cockpit. I took them out and reattached the pieces with fiberglas cloth and resin, and reinstalled them.

kwinters · Post by **kwinters** » Thu Sep 03, 2009 2:01 pm

In keeping her as orgional as possible I have purchased the ouside mailslots from Hightide and am in the proces of reglassing the 90 degree manifolds and stop all the leaks. After looking at Hightides Website and seeing that someone had actually modified the outer mailslots with a stock metal scupper with 5200 I see now how it was intended. As some mentioned, their not cheap but she will be as intended. I did not want to get the station wagon fume effects.

buzzk · Post by **buzzk** » Sun Sep 13, 2009 4:37 am

Do you get the station wagon effect on a Bertram 33 with the rear exhaust? I've been on Bertram 31's and Bertram 28's with rear exhaust and they didn't have the station wagon eefect. I have the mail slots on my boat. They haven't been a problem but I don't like the way they look. Buzz

franklyprice · Post by **franklyprice** » Sun Sep 13, 2009 5:56 am

I imagine you get a little more of that effect. Now that mine is diesel , of course it's straight out the back and I get some fumes when idling or trolling but not really at cruise. Not sure how it would be with the side exhaust. Would you describe the effects on yours as similar Buzz? I also don't like the look of those things , plus one more thing to go wrong. I always thought a sport fish style boat should have two fat exhausts out the back.

kwinters · Post by **kwinters** » Sun Sep 13, 2009 6:05 am

I have went once again with the mail slots. I got the new outer covers from High Tide. We reglassed the entire elbow peices and then glassed them to the inside of the boat. We are now going to attach the mailslots to the outside. All new exhaust hoses. If anything cracks again I think it will the the side of the hull. As far as the tank issue, there were two places that the fiberglass tank was ridgidly attached on each side torward the top that tied it to the upper stringers. That fiberglass strut cracked on the forward portion on the starboard side. I noticed on a earlier photo of a 33 tank replacment that there struts were not in that 33.

kwinters · Post by **kwinters** » Sun Sep 13, 2009 6:24 am

You may find this the most important factor of the repair of the side exhaust. I replaced my old Onan with a new Kohler 7.3 generator and in conditions as a following wind the co fumes from the leaking mailslot arrangment is allowed to get down into the cockpit area. With all the new gens they has a built in co detector which shuts down the engine and is extremly sensative. When the gen shuts down it takes some time for it to reset even if you open the cockpit hatch. Since the gen is so hot, the salt actually bakes in the exhaust assembly and clogs up the holes and the raw water will not be able to flow properly thru the heat exchanger/exhaust. Kohler has made a warranty design change and is currently repairing my gen before we put it back in but the co sensor can't be tricked.

buzzk · Post by **buzzk** » Sun Sep 13, 2009 7:52 am

With the mail slots or straight out the back you are always going to get some exhaust in the cockpit under curtain consitions. I don't think you need them on the 33. But it's not worth the trouble to change them for me. Buzz