Bertram33 User Forum

Took the boat out and did the one engine tests; both engines gave identical gps speed readings (ranging around 8.5 knots); so I guess I'll get the mechanic to take a run with me to check the governor settings and to check if engines are performing as designed. The engines did produce a little black smoke at full throttle when they were operating singly, so I guess that's a symptom that they were in fact overloaded at max throttle.

Well now you know that you don't have one good engine pulling a dysfunctional one, and I think it was worth the effort to diagnose that. I think it's also safe to assume that you don't have bad/bent prop problems either, since it's unlikely both props would be equally out of tune. With similar logic I think you can also rule out a slipping gear. Now I have to wonder what would cause both engines to be slow at the same time. Besides a governor problem, I've also read about injection pumps getting tired and needing rebuilds on the 3208's, and perhaps those would both wear out equally, but I find the odds of that to be a little long. I've never R&R mine, but from what I understand the fuel injection pump is like a little V8 itself, with 8 little dedicated pistons that each feed fuel to an dedicated injector. I also have to wonder if both engines could be running on 7 cylinders, which would make them both equally weak. I'm not sure if you would get a noticable vibration or not. Ask your mechanic about that test to crack injectors one at a time, at idle, to see if you have a dead cylinder. Engines can also get a little tired with age, and with the additional weight of the boat that naturally occurs with age. I've read about people having to take out a half inch of pitch out of their props to compensate for this. But I really don't think that it your problem with only 22" pitch props. You should be under-propped or very close to the mark, as I am with 20x22's. Out of curiosity, how many hours on your motors? Not a big concern with well-kept 3208's until you are in the 5-6000 hour range. Mine have 3100 hours and are still purring away quite nicely. I've heard about guys with 10,000 hours on running 3208's. I think turbo and other restricted air-supply problems can be ruled out, as you would be seeing a lot of black smoke at all above-idle RPM's when under load. I have to think that your engines aren't getting enough fuel for whatever reason. So I would look for fuel restriction problems: filters, governor, injection pumps, and also check to see that all 8 cylinders are doing their job. The easiest thing is the fuel filters- when did you last change them out? Never had the experience myself but I've read that clogged filters can cause the 3208 to loose power. Oh- I just remembered something pertinent: there was a guy on boatdiesel with 3208's who was running 2 micron filters in his racors, because he suspected he had a dirty fuel tank. He had a severe loss of power and went through all kinds of stuff to find out why. At some point he went to 10 micron filters and things got better, and then finally he put in 30 mircon filters (which is what they are supposed to be) and that alone cured all his troubles. Could this be your solution? I'm really curious about your problem and its resolution, as we basically have the same boat, please keep updating your progress. My diesel experience is limited but it is all with this boat and these engines, so hopefully I can be of some help. Next time I go out- maybe I'll play hookey one afternoon this week- I'll do the same one engine test run and let you know what I'm getting for speed and RPM's. Sean Burlingham "Island Time" 1987 Bertram 33 SF Melbourne, FL SBurlingham@cfl.rr.com

Sean, Thank you for your thoughtful comments & the time you're taking to go through the analysis. In answer to a couple of questions you pose, the engines allegedly have about 2300 hours, and all of the filters on both engines were changed at the time of the recent (6 mo ago re-build). I suppose its possible that some crud grew in the 1/4 empty tank during the six months of enforced non-use, but I got down to the boat and bio-cided it the week before the hurricane. The filters, when they were changed were clean and I have a secondary big racor as well as the centrifugal filter. Both engines hit 3050 in neutral and sound silky smooth. I've had vehicles with missing cylinders before and usually the dead cylinder prevents the engine from making full revs. I'm going to set up an appointment with the diesel mechanic, but I'm actually beginning to wonder if the boat's weight is the culprit. When I took off the outriggers (massive ancient Lee models) that was when the boat gained a knot in speed. The tower on the boat is a full tower built from pretty heavy gauge aluminum. Maybe its enough to take three or four knots off the top end. I guess I don't understand the role of a governor in a diesel engine. I know that a diesel under no load spinning at WOT consumes very little fuel, so I suppose it's possible that under load something is preventing the engine from getting all the fuel it needs. I suppose that if the prop pitch were the factor preventing the engine from spinning up to the specified 2800 WOT you would expect there to be black smoke at 2300 rpm, because the engine would be overloaded, and there isn't. I think the primary mystery at this point is to determine the cause for the engine failing to reach max revs. It may be a week before I can get the mechanic onboard, but I'll post his observations.

First, I am glad to have found this site dedicated to one of the best Bertrams ever built. I have an 82 FBSF that is the best of three Bertrams I have had. I started with a 25, moved to a 31 (which was a real classic) and then to the 33. A lot more boat than the 31. I run 3208T Cats with about 3000 hours on them. With a clean bottom and props, I get about 2850 at WOT which on a calm day with the tabs all the way down will produce about 27 kts. on the GPS. I run 21X21 props with a little bit of cup in them. Adding the cups really helped out at the top end. I normally run at about 2200 to 2300 and get about the equivalent in knot speed.

Matt, WELCOME! I'm sure you can add your expertise to the discussions. Al 1978 33 FBC NITES OFF

Welcome aboard Matt, glad to have you here. 1979 Bertram 33' FBC ALEXANDRA Port Richey, Florida HAVE YOU SIGNED UP FOR BERTRAM PRIDE '06 yet? DO IT NOW... SPACE IS LIMITED!

quote:Originally posted by fishybusiness33 First, I am glad to have found this site dedicated to one of the best Bertrams ever built. I have an 82 FBSF that is the best of three Bertrams I have had. I started with a 25, moved to a 31 (which was a real classic) and then to the 33. A lot more boat than the 31. I run 3208T Cats with about 3000 hours on them. With a clean bottom and props, I get about 2850 at WOT which on a calm day with the tabs all the way down will produce about 27 kts. on the GPS. I run 21X21 props with a little bit of cup in them. Adding the cups really helped out at the top end. I normally run at about 2200 to 2300 and get about the equivalent in knot speed. OKay not you've got my interest- those are great speed numbers- where I would like to be, and I'd like to know some details about your boat. What HP rating are your 3208's? Mine are 260, and I'm thinking of bumping them to the max non-aftercooled rating of 320 HP. What shafts are you turning? Bertram gave me the 1.375" ones which are marginal now. What gears do you have? Mine are the Twin Disk MG502-1, which are rated for 260 HP. So, if I upgrade engines and not gears they would be technically underrated. Although a Twin Disk guy told me they should be fine it would still be a little spooky. I'm turning 20x22 props and I'm quite surprised at your numbers with 21x21's. Would have thought that the pitch dictates speed more than the diameter but maybe I need to re-think that. I also have a set of balanced 20x23's but I have yet to try them out. I can get your WOT and cruise speeds with an empty boat, clean bottom, and a 1/3 or less tank of gas, but loaded down I can't approach them. Can you achieve 21k cruise with a full tank of fuel with people on board too? If so, I've got something wrong. My boat (and I'm sure this is true of them all) seems to want to live at 21-22 knots, the ride feels right there. Until I can manage to get those 370 BTA's or a maybe strong yannies, I'd like to try to get there with what I have, such as you are. Welcome aboard! Sean Burlingham "Island Time" 1987 Bertram 33 SF Melbourne, FL SBurlingham@cfl.rr.com

Robert- any news on your boat? Have you looked at your Racors to see if you've got 30 mic filters? Sean Burlingham "Island Time" 1987 Bertram 33 SF Melbourne, FL SBurlingham@cfl.rr.com

quote:Originally posted by Sean BurlinghamUntil I can manage to get those 370 BTA's or a maybe strong yannies, I'd like to try to get there with what I have, such as you are. Ask and ye shall receive: http://cgi.ebay.com/ebaymotors/ws/eBayI ... PcY_BIN_IT Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth Marblehead, MA [img]http://www.bertram33.com/photogallery/p ... sabeth.jpg[/img]

I've got my boat on the hill to replace shafts (wrung one off last week) and plan on playing with props while I'm out. My boat has the 300 6bta's, which are a lot lighter than Sean's 3208's and rated at 40 more hp each. Your performance numbers are currently better than mine, so I wonder if I've been propped too lightly with 21 x 20 4 blade props (1.53: 1 ZF gears). I know my particular boat is heavy, with extra fuel, etc. that I run 28,000 lb loaded. Is your boat significantly lighter? I don't want to overload the engines, but based on what I've seen and heard of other boats' setups I shouldn't be close. Anyone got any real-world experience with this boat weight, these exact engines and gear reduction?

quote:Originally posted by dougl33Ask and ye shall receive: http://cgi.ebay.com/ebaymotors/ws/eBayI ... PcY_BIN_IT height="1" noshade id="quote"> I know, I know, been watching that sale, or I should say no-sale, since you first posted it. He recently re-listed them after no buyers. Too bad there is not a way to test them out, under load, before buying. The only way I know to truly test them is to put 'em in and try 'em out. Too scary a proposition to R&R with as-is engines that are a gamble, although at that price it is awfully tempting. I like to gamble with cards, not boats. Sean Burlingham "Island Time" 1987 Bertram 33 SF Melbourne, FL SBurlingham@cfl.rr.com

See if he'll trade for the Proline. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth Marblehead, MA [img]http://www.bertram33.com/photogallery/p ... sabeth.jpg[/img]

With 84% positive feedback I wouldn't buy anything from that guy, especially supposedly rebuilt diesel engines with no warranty.

I change my Racors out on a regular basis (70hrs or less), also same with air filters. I have noticed, however, that by leaving the engine hatch cracked slightly (sponge under aft end of hatch edge) that I will now achieve higher RPM. My uneducated guess is that the Cats are not getting the air that they need to run to peak performance. I have also noticed (anyone else?) that the engine vents are positioned different (fore/aft) on simmular vessels. I have two vents on each side. Forward one is faceing forward and after one is faceing aft. I have noticed that on some Berts that both are faceing in same direction. Maybe a gas/diesel thing? Any input! Steve

Steve, I think the vent positioning was based on the phase of the moon the day they were installed. My gas is set up the same as yours. Al 1978 33 FBC NITES OFF