Bill, welcome.

First thing, please click on 'UserCP', upper left corner of this page, and set up an automated signature including information about your boat. You can use my signature as a model of the kind of info to include in your automated signature. We need this information in order to know what kind of boat we're discussing...it makes a big difference to us old-timers, as we can then clearly visualize the layout and systems that you are grappling with.

Thanks.

Bill,
It sounds very much like you have a crop of barnacles on your prop that could feed a third world nation. Reverse gear has a higher ratio than forward, so it makes sense that you could reach max rpm while in reverse, but not in forward. It might also be a plastic bag, but I doubt it. Grab a pair of leather gloves and a paint scraper and go at it. Over the course of a season I found my top speed drops by about .7 kts. Upon haulout this month, the bottom was pretty clean, but the prop was covered with a bunch of tiny barnacles. That was using the boat just about every weekend in Long Island Sound waters. I can only imagine how bad the barnacles are after sitting in FL waters for 7 months!!!

Bill, I would agree with Toms suggestion of cleaning and inspecting the prop as sitting that long there is bound to be some hefty growth on the bottom and prop. The drag created by this growth can be substantial, I have cleaned my own bottom using a snorkle and mask and found that the wetted area is about fifteen acres. If the boat has been in the water for seven years my guess is it has the equivilent of one hairy dog per square yard. This would be like towing about a couple hundred limp hairy dogs behind you. Surprised you could move out of the slip.

As for the overtemp I trust you checked your intake strainer to make sure it is not obstructed and if the heat exchanger has been unmaintained for seven years you may have very little efficiency from it, the engine may cool well enough unladen but, under demand you ask a lot more of the heat exchanger.
There could be one of those dogs stuck in there.

If low rpm is created by added drag of the hull or prop you should see a lot of black smoke as you advance the throttle as the engine will be getting far more fuel than the rpm would require. If the exhaust is not turning black, you may have restricted fuel flow to the engine. Like the bottom if the fuel has been sitting in the tank for seven years you may have something far more frightening than dogs growing in there that could be restricting the filters and limiting RPM. I doubt the symtoms would be from water in the fuel, I hope that is not the case as water can be horibly damaging to a diesel as water is non compressable and if injected into the engine can quickly cause broken pistons, cracked heads and worse. Please check you primary filter for water in the bottom of the bowl.

I congratulate you on your new boat, and understand your desire to go sailing but, my guess is you have some maintenance to do after seven years of sitting, you will want to address the engine temp and RPM issues asap, operatiing it without further diagnosis could risk the engine. I would up needing to overhaul my engine due to an overheat early in the ownership of my boat, it was an expense that was untimely and I had many other things on my bucket list that I would have prefered to dedicate those funds to.

Please keep us up to date on your progress and do not hesitate to look for suggestions here.

Welcome aboard.

Steve

Bill, I had almost exactly the same symptoms as you are having. The engine ran good at idle and when out of gear would easily rev to 3000+ RPM with no overheating. When underway, the RPM would not go above about 2300 RPM and the engine overheated. My boat had recently had the upgraded 3" heat exchanger installed, so I knew that was not the problem.

I won't bore you with all the things I tried and money I wasted before I found the problem. In the end the problem turned out to be in the muffler and wet elbow. There were two problems:

The first was that at some time raw water flow had been interupted and the muffler inlet got so hot that it burned the resin out of the fiberglass muffler inlet tube. This let the residual fiberglass collapse into the muffler inlet, apparently creating enough back pressure to reduce cooling water flow.

The second problem was that corrosion had built up in the wet elbow so that there was only about a 3/8inch diameter hole for the exhaust to pass through. No wonder the engine had no power!

I replaced the muffler and built a new exhaust/wet elbow assembly out of 1-1/4 pipe. This solved both the overheating problem, and the loss of power.

Gary, good thought on the restricted exhaust elbow, I had failed to think about that as an issue.

Bill, sorry, I mis-read your post and had in my mind the boat had been sitting for seven years not seven months. You are only towing the equivilent of some small dogs.

Steve

Nice signature; thanks.

Given how long the fuel has been in there, you'll want to frequently inspect the glass sediment bowl on the Racor. Water contamination in the fuel ought to be visible in that bowl.

I had a pronblem with buildup in the line from the tank to the water serperator filter where the line goes into the filter and makes a sharp turn. Since the boat was standing so long, you might want to check that filter head too.

Squint,

I've been going through my new boat which had sat an unknown amount of time with just occasional go-outs and declining maintenance as the previous owner lost interest. There was plenty of algae in the water separator bowl and housing. So much so that when I opened the drain, some water came out but no fuel - the layer of algae was so thick that it supported the diesel above!

From previous experience I knew that simply changing the filter element and wiping the bowl would be insufficient, so I completely removed the housing and disassembled the entire unit. All surfaces of the centrifuge assembly, as well as every nook and cranny, o-ring, etc., were coated with algae buildup. After washing each piece in diesel and reassembling, that thing is really clean! There's little point in changing the filter element and not breaking down and cleaning the housing assembly if there is algae growth in there to begin with.

Of course there's still algae in the tank and hoses, but the water separator is a major collection point. Upon the long-standing advice of the local diesel expert, I don't use biocide because the dead algae will, as you said, still flow downstream and clog things up. Instead, I have been sold on Soltron, an enzyme-based treatment that eliminates water and also eats (literally) any living crap in your fuel. I have never had a fuel system get as bad as this one, but I've used Soltron successfully in a new Yanmar and an old Volvo. The diesel guy says that in particular if you suspect lots of growth in older fuel a treatment with Soltron is highly to be recommended over biocides. Perhaps the foam you mentioned has the same properties.

More info is available at [url]http://www.navstore.com/soltron.aspx[/url]

HTH

- nick

PS I am jealous, haven't got to sail my new boat yet, after nine days of cleaning/maintenance I am getting anxious! Congrats!

FWIW, if it were my boat I wouldn't touch that Start button until the remainder of the fuel system (hoses, tank) were cleaned and proven spotless, and a new load of fresh diesel were onboard. Seems to me that the issues you describe are applicable to the entire system.

Well, several things play into that, among them financial resources that are spread thin among the many areas of the boat that more or less urgently need attention. The engine did perform without a hitch on the initial view at the dock, on the short trip to the yard for survey, on the sea trial, and on the 23nm run home after purchase. I've not only cleaned out a whole mess of that muck, but have established a baseline at the primary filter and will keep close tabs on how much more crap comes downstream. When I can I'll clean the tank, replace the hoses and polish or replace the fuel. My boat's in the water and in use full-time, so I'm just chipping away at it!

Thanks,

- nick

this may be way off track, but three years ago temp started to go up, rpms could advance, but no change in speed.

one of our injectors had failed. One friend, then one mechanic suggested each of the test listed below:

1) with engine runnning (and cover off) use a wrench to crack loose an injector. If fuel starts to leak from the base of the injector and the engine slows, that injector is good. Tighten it and go to the next one. If when loosening fuel leaks, but the engine does NOT slow.....bad injector

2) another test.....if it is an injector, put the boat in reverse and the engine is likely to stall.

Brian Giersch
Encore #1245