How often do you check your belts on a shaft driven boat?

RIN

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Not outdrives, obviously, as you just lift up the engine hatch as easy as wink.

We had an instance last week where we a belt on each engine failed at the same time. See the "KAD300 help required" thread if you want more info.

I haven't really checked my belts much at all this year as its a real faff to unbolt the table, roll up the carpet, remove floor boards and remove soundproofing to get to the engines under the cabin floor.

So if you have a boat with the engines under the Lounge, I would love to know just how often do you check the tension on the belts, or if you do at all.
 
Not outdrives, obviously, as you just lift up the engine hatch as easy as wink.

We had an instance last week where we a belt on each engine failed at the same time. See the "KAD300 help required" thread if you want more info.

I haven't really checked my belts much at all this year as its a real faff to unbolt the table, roll up the carpet, remove floor boards and remove soundproofing to get to the engines under the cabin floor.

So if you have a boat with the engines under the Lounge, I would love to know just how often do you check the tension on the belts, or if you do at all.


How do you check your oil and water levels though, is there a separate access panel?
Belts I don't check very often, they were in good order when I serviced the engines (looked new) but I will make a point of doing it more regularly!
Totally get the point about the faff, I can check oil on both engines and water on one by lifting an access panel, but the other engine water filler cap is under a panel under a heavy sofa...
I've come up with a system now of lifting the sofa on a block of wood which allows enough space to slide the panel out to check the water level, but why on Earth that hadn't been considered when the boat was designed I have no idea!
 
How often do you check your belts on a shaft driven boat?
Every time I do an engine check I feel the tightness of the belts although in truth, the belt cover stops me doing a visual inspection
 
On my old boat we had a hatch -so it was access was easy ,so every day .
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On my next boat a big E room where I can get to all sides so agian -part of day to day checks -there only one belt and it's at the front -I can check it from the side ,it has no cover -there's a big enough gap @ the bulkhead under the light on the pic

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First question you gotta ask is do the belts drive just alternator, or jacket and/or sea water pumps too?. If a belt drives either pump then it is mission critical and I'd say it should be checked often and renewed often. If it drives only the alternator then it doesn't matter it if fails - that's my set up (caterpillar engines) so I hardly ever check belts and i have them replaced at 300 ish hours or every second year. I suspect they'd last 1000 hours.

Volvopaul might be able to tell us which engines in marine use have mission critical v belts. In gensets at the sizes used on this forum, Kohler use belt driven seawater pumps generally, and the Kubota engines in Cummings onan gensets have directly driven pumps so the v belt drives only the alternator
 
I have access through a door in the Lazerette, and check oils/waters before and after each trip. Belts can't be seen this way, but can be felt by hand. Tachometer stops working when belt needs tightening.
 
Around the Solent not often enough, may be once very other weekend. On a run every hour underway to check for leaks, smells, smoke, etc.

Still didn't stop me throwing a belt after a bumpy Poole Bay crossing earlier this year which considerably shortened a planned weeks cruising, whilst I sorted the problem out, which was the alternator drive pulley which had worn away the shaft beneath it.

NB On my Cummins the belt also drives the fresh water pump, so no belt means no cooling much above idle, and an immediate overheat if the belt throws at power.

Many VP TAMD etc have separate belts - for the alternator and the water pump.
 
NB On my Cummins the belt also drives the fresh water pump, so no belt means no cooling much above idle, and an immediate overheat if the belt throws at power.

Many VP TAMD etc have separate belts - for the alternator and the water pump.
Ah ok. As I said you need to identify what it is that your belts drive before deciding your checking/maintenance regime. A non functioning alternator is neither here nor there; a non functioning water pump is a whole different story!
 
Ah ok. As I said you need to identify what it is that your belts drive before deciding your checking/maintenance regime. A non functioning alternator is neither here nor there; a non functioning water pump is a whole different story!

Agree re water pump -abviously
Alternator -not so sure -reason -modern diesels are power hungry with black boxes , electronic injection. Etc .
If the bat drains off and can not be recharged ( depends on how your boats wired * ) -then systems will pack up = stop engine .
The dumper truck on a building site or paddy pump or ancient gardner 6LB with no electronic,s will run with out power .

* unless you motor around with finger depressing x over switch ? -grabbing power from t,other side ?

Had a Porsche once and Alternator packed up a long way from home .AA man had to boost bat every 1/2 hour , that's how long it lasted before conking out - with no charge going in .The "electric,s - injection , black boxes ECU , -consume more than you think .
 
Interesting debate. Currently a non-boat owner but I used to do engine checks very frequently. Whereas I almost never look under the bonnet of my daily driver. And yet, which is more scary, having to anchor in Lake Solent until Seastart turns up or waiting on the hard shoulder of the M1 for the RAC?

No doubt the salty seadogs who haven't seen land for six months and are posting on here via their sat-phones will want to shoot me down in flames. But really, if your boating consists of glorified trips round the bay, why bother getting oily - unless that's what you enjoy?
 
Interesting debate. Currently a non-boat owner but I used to do engine checks very frequently. Whereas I almost never look under the bonnet of my daily driver. And yet, which is more scary, having to anchor in Lake Solent until Seastart turns up or waiting on the hard shoulder of the M1 for the RAC?

No doubt the salty seadogs who haven't seen land for six months and are posting on here via their sat-phones will want to shoot me down in flames. But really, if your boating consists of glorified trips round the bay, why bother getting oily - unless that's what you enjoy?

As a PS to the above, I would just say that I am rigorous in ensuring that all my road vehicles are maintained by people with the right diagnostic and remedial skills and equipment in accordance with the manufacturers' schedules. Hence, why not just do the same with marine tech?
 
Well I asked the question as moving from a sterndrive boat (we checked the engine compartment visually after starting the engines before every trip, and when under way, and regularly checked oil and belts) because access was so so easy.

Now we have a shaft driven boat and the engines are under the lounge it takes a lot of effort to even look into the engine room let alone check the condition of belts

I was hoping to get a feeling from this post as to how often shaft drive owners pulled up the floorboards to look. Perhaps I should have done it as a poll, I might have got more definitive answers.

One of the things I am considering is installing a few cameras in the engine room as we have a Raymarine E120 at the lower helm and it will cycle through (four I think) video inputs. On the other hand it will not network the video to the upper helm so it would still require trips up or down the stairs so maybe someone has a better solution to this.

Funnily enough I never ever check the condition of belts on my car:)
 
If the bat drains off and can not be recharged ( depends on how your boats wired * ) -then systems will pack up = stop engine.

It could be serious if you have electric or electronic engine throttle/gear controls or steering.

I can't see what the fuss is all about.
In the worst case, you can always turn on the genset and keep the battery charger running, so I would agree wholeheartedly with jfm that a non working alternator on one engine (or even on both at the same time - but how unlikely is it?!) ain't mission critical at all.

Re. the OP question (having said that also in my boat the belts only drive alternators), I look for dust and check the tension almost every time I go in the e/r. In fact, I even had the belt covers removed!
Oh, and just to save any SH&E fan the hassle of commenting on that, no problem to declare myself guilty as charged! :)
So far, I can't remember to have needed a tension regulation more than every other year.
And ref belt replacement... Erm... Hang on... I can't remember how many years ago I did that! :o
 
I was about to suggest fitting cameras to aid monitoring.

I have 3 cameras fitted in the e/r, and am considering more, as they save me a lot of hassle and worry because I can keep an eye on things both before during and after passage.

No, cameras won't check belt tension but they will spot dust & dirt build up beneath to indicate early warning of failure or problem, provided your bilge is clean enough (mine is).

Cameras are so cheap now and easy to fit, they seem the obvious choice to reduce the inconvenience of carpet and hatch lifting.
 
I can't see what the fuss is all about.
In the worst case, you can always turn on the genset and keep the battery charger running, so I would agree wholeheartedly with jfm that a non working alternator on one engine (or even on both at the same time - but how unlikely is it?!) ain't mission critical at all.

A lot of boats and particularly smaller boats generally don't have gensets as a backup in this scenario and hence modern engines it will be a problem.
 
It could be serious if you have electric or electronic engine throttle/gear controls or steering.
Why? You have the other alternator, and you might have genset(s) and 230v powered chargers for your DC system. One busted alternator is surely very unlikely to spoil your day unless your boat spec is very light to begin with.

If anyone has twin engines but the 12/24v systems are 100% isolated then honestly they should consider changing their wiring so that either alternator will charge either set of engine batteries. I've never come across a 100% isolated set up.

In the final analysis you can just carry a spare belt and change it in the very unlikely event it fails. That's something you might have to do regardless of whether you check the thing every time you go out. You'll never have to do that in a shipping lane or while berthing in a strong wind: the batteries will keep the engine running until you've found a comfortable place to stop for 20 minutes to change the belt
 
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