Got to move engine forward (new shaft etc.) - any tips?

[Poignard]

If you did decide on a flexible coupling, the Centaflex 127 is very good. I have had one since 2002 and it has never given any trouble.

4" Centaflex M127 PRM 1" Shaft with Stud Kit | Aquafax

 

[jwfrary]

If you did decide on a flexible coupling, the Centaflex 127 is very good. I have had one since 2002 and it has never given any trouble.

4" Centaflex M127 PRM 1" Shaft with Stud Kit | Aquafax

My go to for a flexible coupling however it’s not going to achieve any forward movement as the shaft penetrates the housing nearly as far as a normal flange.

Great for vibration reduction though! Without the hassle and length of a cv joint

 

[bluerm166]

After Beta increased their recommended 250 above WL to 300 I reviewed our installation which was already tight ,despite the high rise elbow ,and have installed a nice high Vetus anti syphon valve. I note that in the current Beta installation manual (P 25 for a 16) they actually show a well-below-the -waterline engine where a high rise elbow would be insufficient that employs only an anti syphon loop and valve to overcome the issue.
Would adding only the latter,which can be achieved using flexible hose and if necessary even rise into the cockpit or cabin be an acceptable solution - obviating the need to shift the engine ? There is still an issue in ensuring that the route and fixings for the hose don't prevent the engine from moving radially that needs to be considered .

 

[Graham_Wright]

I had a bad experience with Norris.

 

[roaringgirl]

If all this is just for a temporary solution to get you 40nm and there's other stuff you'd rather be fixing in preparation for it; why not just get a tow 40nm?

 

[jwfrary]

After Beta increased their recommended 250 above WL to 300 I reviewed our installation which was already tight ,despite the high rise elbow ,and have installed a nice high Vetus anti syphon valve. I note that in the current Beta installation manual (P 25 for a 16) they actually show a well-below-the -waterline engine where a high rise elbow would be insufficient that employs only an anti syphon loop and valve to overcome the issue.
Would adding only the latter,which can be achieved using flexible hose and if necessary even rise into the cockpit or cabin be an acceptable solution - obviating the need to shift the engine ? There is still an issue in ensuring that the route and fixings for the hose don't prevent the engine from moving radially that needs to be considered .

The anti siphon prevents additional water entering the system via the inlet seacock when the engine is off. This risk is reduced if the engines well above the waterline. The anti siphon in itself will not allow you to keep a unacceptably short run to the water lock.

The reason this distance is specified is to prevent water in the water lock, which collects what’s remaining in the exhaust system, from sloshing easily up into the engine in a seaway.

If you can I would recommend exceeding the requirements significantly, fit a hi rise where it is possible rather than where it is needed and when anticipating rough conditions draining the water lock might also be prudent. (Draining your water lock might assist the OP until a proper modification can Be done)

Bear in mind a longer exhaust run will have far more water left in it than a short run and therefore a bigger water lock is required.

I had a engine come in that had been rebuilt not a few hundred hours ago by someone else. It had been rebuilt due to a hydro lock. The root cause wasn’t identified it was re installed abs the exact same thing happened this time snapping the rocker shaft!

Poor exhaust installation is probably the no 1 cause of marine engine failure next to corrosion abs general neglect!

Vetus have some good advice with their products.

For modern production boats with shallow bilges most of the time the stock elbows are ok. But on anything with a significant round the the belly say pre 2000 you probably need a serious critical look at your exhaust system if your planning anything more adventurous Than motoring from the Hamble To cowes on a calm day!

 

[bluerm166]

Yes,you are quite right to point out that this is the killer issue detailed by the OP,rather than the anti syphonage issue.

 

[jwfrary]

Yes,you are quite right to point out that this is the killer issue detailed by the OP,rather than the anti syphonage issue.

Apologies for the ranty nature of the post!

 

[greeny]

I don't know the type of boat or the engine location, under companionway or under saloon table. Everything on here is about moving the engine.
What about moving the woodwork? That may be a whole lot easier if it does not affect the asthetics too much or need structural components moving.