Reconditioning AD41s

[alb40]

If they run and perform well, why bother wsting money searching for a problem you dont have.
Compressions tests aren't accurate, their only a guide so user error can create duff readings.

As for the smoke, they all do it as everyone has said. If the neighbours don't like it, rev them up and make them cough!

 

[hlb]

A little story.

My engines smoked like hell.

n the distant past, before Soltron was readily available. I wet to Guernsey and met up with Dom of these fori?

He gave me some Soltron and I sloshed it in the tanks.
On my return, the boat went up on the hoist for a quick prop change.

My mechanic jumped aboard on it's way down the hoist, and on starting the engines. He said. Weres the smoke gone. /forums/images/graemlins/crazy.gif

 

[DAVIDO]

I have tried a fuel additive but not Soltron. Will give it a go. Do you need to keep adding it i.e. each time you fill up?

 

[hlb]

Please yourself. But it will just go back to smoking eventually, wont it.

Personally, I have not put any in for ages. But then if I fill up at my marina, they have already added it.

I'd stick some in the filters, to get the job started, then double dose in the tank. Then go for a couple of long blasts.

I've given up bothering about a bit of smoke!!

 

[Tim777]

I have AD 41 A's. If you are getting the revs to the max ie 3800/3900 and the boat when clean is not slower than previous season I cant see that there is much wrong. Is your speed the same as other Sealines with the same engines?

I noticed big variances in the amount of smoke dependant on which fuel supplier I used. Cold still weather always makes it much worse when the engines are more reluctant to start and are slow to warm up. I don't consider it is a proper start unless the pontoon is obscured for at least a minute.

Relax and enjoy the boat!

 

[dragoon]

Hi David,
looking at the compression figures you report, it is fair to say that whilst there are some differences between the pots, I would ignore the absolute numbers.

The first sign of low compression is generally poor starting. Secondly I would expect that you would be down on WOT if some or all of the cylinders are reading low. Since this doesn't seem to be the case, I would be inclined to read that there's probably not too much wrong with the combustion chambers.

A few other simpler things to verify;

- check (and adjust as necessary) the valve clearances - as mentioned earlier by someone

- does your engine have heater plugs? If so are you using them?

- there's a slim possible that the timing may be out ever so slightly. You could have that checked.


Beyond that, I believe if you have them rebuilt that you'd be looking at a lot of expense for little gain since it may not solve the problem. The other thing is that rebuilding the complete engine is a very costly exercise (at least to do it properly) and I would want to see the creditionals of anyone who was going to do it. Even if you do peform a "basic rebuild" with pistons,sleeves,bearings etc it's still not a complete engine rebuild as you'll be on the same timing pump, turbo, cooling system etc. Hence, I would be tempted to keep the money and enjoy the boat.

Incidentally I just 'rebuilt' one of my 40bs after a valve broke (after 26 years - quite a bit of which was spent on the river also). I can tell you there was no noticable wear inside the engine and I opted to repair only that cylinder which required fixing. The head was sent away for repair and I originally was going to have them replace all and sundrie as a matter of course - you quickly find yourself moving away from the approach of changing any and everything - as an example, the exhaust valves were over 60 pounds each!! In fact, even with doing much of it myself, the total repair still came to around 2000 pounds.

I wish you luck whatever you do. I suspect you really have a cracking boat but maybe worry a bit too much (like me).

All the best.
Paul

 

[oldgit]

If the injectors are weeping you will end up with an "increase' in level of oil on dipstick after any decent trip out on boat.Oil pressure will drop markedly.This is a very noticable feature of a serious injector problem.
Suspect your engines need a blooming good hot and hard long run.