Impossible to Fix Westerbeke? 7.6BTD mocks all repair efforts!

[MicHughV]

does that genny have a thermostat ?? could it be corroded shut... ??

another poster opined, and it's where I would start....at the impeller.....is the impeller shaft turning ? Can you turn the shaft by hand while on the engine ? If so, the shaft is broken on the inside. There should be a small nub sticking out of that shaft which catches on the impeller making it turn...the nub is not big ....about the size of an "o" as typed here. Inserting a new impeller requires sliding it over that nub correctly.

there is a half moon curved plate inside the impellor housing that forces the impeller blades to fold...is that plate still there ?? If there, is it worn ??

Inside the impeller housing is a small opening directing cooling water to the heat exchanger.....I've had instances where an impeller blade broke off and a small piece of rubber got jammed up inside that opening...

just some thoughts on the matter that I've had to contend with in the past.

[sinnerman]

How about disconnecting the raw water hose exiting the heat exchanger and having it dump into a bucket??

Run the generator for a few seconds and see how much water comes out.

If the flow is good, then your problem is downstream.

[Sailshabby]

Everyone has covered potential solutions, but please keep us apprised. On the lighter side, once you neck it down and fix it, YOU’LL be the CF Generator Guru everyone looks to for their answers!

[SVTatia]

Originally Posted by Tspringer

...

I am also going to search here in Nassau for a large electric pump and under the waterline strainer and the hardware to plumb that in line below the waterline to have a boost pump for the entire system. Problem is I think getting all that is needed in Nassau is wishful thinking. I also cannot determine how to wire the pump to turn on and off automatically when the generator is making power.

I hate this generator. My little Honda is exponentially more reliable.

If the injector elbow is hard to remove, I bet no one has done it before, so my money is there also.

Be very careful with that electric pump, you will inject a lot of water in that possibly has no way of getting out. The last thing you want now is to flood your cylinders.

[jimbunyard]

Originally Posted by SVTatia

...Be very careful with that electric pump, you will inject a lot of water in that possibly has no way of getting out. The last thing you want now is to flood your cylinders.

Yeah, that's not really a good idea unless extenuating circumstances make it necessary; it adds multiple failure points and un-needed complexity to a system that, in proper repair, will be robust and relatively trouble free.

Seems a frustration-borne idea, understandable, but really falling under the 'just because one can, doesn't mean one should' rubric...

[bongo]

Does your boat have an external bronze intake strainer? I once had a small octopus take up residence in one on my previous boat. I’d get great water flow when the sea-cock was opened, but would get nothing when the water pump was sucking on it. Pulled out the octopus, limb-by-limb, and VOILA!

[MicHughV]

the Bennie 473 has the genset at the very tailend of the boat, how they get it in there, I have no idea...the 432 has it under the cockpit seat, much easier to get at...

interestingly, most all the 473's I've seen had the rear edge of the transom about 4-6" underwater at rest, this should not be so, on those French planing hulls, but could also be a cause for generator problems??

My gut feeling is the impeller...broken shaft....broken nub...worn half moon blade bender...piece of impeller stuck somewhere...something....but my focus would be the impeller...

[Tspringer]

OK - after much wrestling, muscle cramps and cursing I got the raw water hose disconnected from the output side of the anti-siphon. I turned it around to dump in a bucket and fired up the generator.

Water came out of the hose into the bucket significantly faster than has been flowing out the exhaust. So I interpret this as a clogged exhaust elbow.

It seems the elbow must come off. So I have been working on that. Getting the hose that feeds from the fitting on the generator to the water injection fitting off has so far taken 2 hours and its not done. The hose clamp is perfectly positioned to ensure that it is impossible to get either a socket, wrench or screw driver on it. Were this hose clamp screw positioned 2mm up or down or in any other position removing it would take no more than 1 minute. Why? Why not actually think about the positioning of the generator in the boat and future maintenance?

On with the effort to get the elbow off. I have bruises in places nobody should

[Tspringer]

Originally Posted by MicHughV

the Bennie 473 has the genset at the very tailend of the boat, how they get it in there, I have no idea...the 432 has it under the cockpit seat, much easier to get at...

interestingly, most all the 473's I've seen had the rear edge of the transom about 4-6" underwater at rest, this should not be so, on those French planing hulls, but could also be a cause for generator problems??

My gut feeling is the impeller...broken shaft....broken nub...worn half moon blade bender...piece of impeller stuck somewhere...something....but my focus would be the impeller...

YES -- my transom is under water as you describe. When I haul out for bottom paint next month I will be changing the line and bottom painting that section of the transom. Poor design.

[boatman1]

Is there a water lift canister (muffler) installed? I may be mistaken, but these devices are what cause the “surge” in water volume every 5-10 seconds or so. So if your exhaust does “surge” (albeit weakly) then there’s one on your boat. Perhaps there’s some blockage or failure there? Those things are pretty bullet proof, but.......
No doubt you can’t get to it, so you are left with getting access via some boat surgery. Oh the woe

[Tspringer]

Originally Posted by boatman1

Is there a water lift canister (muffler) installed? I may be mistaken, but these devices are what cause the “surge” in water volume every 5-10 seconds or so. So if your exhaust does “surge” (albeit weakly) then there’s one on your boat. Perhaps there’s some blockage or failure there? Those things are pretty bullet proof, but.......
No doubt you can’t get to it, so you are left with getting access via some boat surgery. Oh the woe

No muffler that I can see and I can see the entire routing of the giant exhaust hose.


Removing the exhaust elbow appears to be impossible with the generator in the boat. Even if the generator is unbolted it only has room to slide back about 2" which does not help. The strap bolt holding the large exhaust hose to the exhaust elbow output is (like the other one) perfectly positioned to ensure it cannot be removed. Whomever at Beneteau oversaw the generator installations should not be working in boat building.

[MicHughV]

I looked at the 473, but that transom in the water was off-putting to me....
so I opted for the 432...which has the transom out of the water...I guess the genset could have been placed in the back on the 432, like the 473, but maybe Beneteau wised to the transom dragging in the water bit.l
But, the 432 has it's own problems. The weight of the genset under the cockpit seat causes the boat to have a permanent list....on my boat that was addressed by the builder glomming some big chunks of lead to the other side of the hull to offset the genset weight... but I've seen some 432's, with aftermarket genset, and no lead counterweights, that have a pronounced list.

While we are on it.....the Beneteau has a very flat hull...as you well know...the bilge is a mere shoebox sized indentation in the keel. When the boat is heeled over, any water inside the boat runs to the low side, not the bilge, so you need to keep an eye on this.

I installed a "bilge alarm" that is wired to the float switch. It makes a sound to raise the dead. It is wired with a switch so I can turn it off. Water slopping around inside the hull can activate the float switch, which in turn sets off the alarm, otherwise you can end up with 100's of gallons of water inside the boat, before you are aware of it.

Besides that and the low lifelines, it's a great sailing boat.....

[Tspringer]

OK --- Removing the exhaust elbow is a no go. The generator cannot be moved in a way to improve access to the bolt on the strap holding the large exhaust hose to the exhaust elbow. This bolt is in the one position where no tool can be put on it.

So I did make a coat hanger wire tool - S shaped with a tail - fished it through the water injection fitting on the exhaust elbow - found no blockage. In fact it moves around all through the fitting and down into the exhaust elbow itself just fine. Everything around there and looking inside with a mirror seems shiny and nice - no indications of any rust or such anywhere. I see no indications at all of any sort of blockage at the exhaust elbow and certainly nothing to justify drastic measures to try and remove it - it looks like new. (this generator had 450hrs when I purchased it in 8/19 -- now it has 989. Until this issue I had no problems with it at all and maintained it fanatically)

I really have no means of accurately measuring the water output from the hose disconnected at the exit side of the siphon (this is after the raw water pump and heat exchanger but before the exhaust elbow) but it does appear to be more flow than what was coming out of the exhaust? There is no effective means of capturing the water coming out of the exhaust to somehow compare.

I do have the swim platform shower that I could use to hook up to the raw water feed at the strainer. I am considering removing the shower head, cramming the handle into the hose and tightening a hose clamp on it and then running the generator with the shower water turned on just to see what happens. Would the fresh water supply pump provide enough water?

I am going to try the suggestion of flipping the impeller pump cover. I am removing it - stripping off the red paint and such and then re-installing it upside down with another new o-ring just to see if that makes any difference.

The raw water feed hoses are 1" ID -- but many of the fittings in the raw water system are only 1/2" diameter or maybe less based on eyeballing. While we never had any issues before, I wonder if the entire system is just very poorly engineered and susceptible to this sort of issue if not in 100% absolute perfect conditions. Any minor issue = overheating.

It may be that the entire raw water system needs to be re-engineered. Larger fittings, below water line strainer, fewer sharp turns in fittings (no 90 degree elbows) and perhaps a booster pump.

[rslifkin]

I'd be very surprised if you need a booster pump. Typically, the existing impeller pump can move more than enough water if everything else is good (even if it has to lift a good distance from the intake).

[jimbunyard]

There is more than one way to skin a cat...

If you can get the Vclamp holding the elbow loose, you may be able to rotate the elbow enough to get to the hose clamp.

If not, you might be able to remove the clamp at the other end and remove the hose and elbow together.

Hopefully you have clamps with hex head screws so that a small box-end or open-end wrench can be used. In a worse-case scenario, a Mapp gas torch gets hot enough to bend a small wrench to fit special circumstances.

Of course a way of holding the wrench is required; a small vise or a couple of vise grips will work fine.

To state the obvious, when you get it off, make sure the hardware is accessible for your installation, which is not something a 'production' boat builder is going to worry much about.

Call it a down side of the initial low price...