ZF or Twin Disc....?

[Canopy Locked]

If you were having a new engine & G/box, which gearbox type would you specify and why?

Thanks

Rob

 

[oldgit]

Stick to cast iron ?

......something I read on www.Yachtsurvey.com a while ago

"The marine engine industry tried cast aluminum once before back in the late 1960's; it didn't work then and won't work now, never mind all the smoke they'll put out about "technological advances." The German transmission manufacturer Z-F has tried making cast aluminum gear boxes, a foray into the future that has blown up in their faces along with their gearboxes. Aluminum is simply too weak to handle these kinds of loads, too heat sensitive, and unresisting to corrosion to be an acceptable substitute. " ?

 

[dustywings]

I re-engined last year and went for ZF mainly for the weight advantage over twin disc. An uneducated feeling is that if you are looking at a commercial application then twin disc may be the better bet but for leisure ZF are a very fine box. I have the 220As and they have been faultless so far. During the installation I had dealings with the ZF technical chaps and they were very helpful which of course they should be but sadly it is never a given!

 

[Deleted User YDKXO]

I've had Twin Disc boxes on several Cat engined boats and they've never given me a moment's concern (he says touching wood!)

 

[Nick_H]

Dustywings

Why would you keep your boat in Hamble when you live in Lymington?? Its none of my business of course, just seemed an unusual choice, especially when the drive between the two can be pretty horrible traffic wise.

 

[volvopaul]

It depends on what engine make, horse power range type of boat etc. I can say that zf are having a rough time at the moment over there 280 married to the d9 500hp engine as it only rated to 480hp the d9 torque curve is very steep and makes grinding paste of the gears. Volvo now use twin disc on the d9 , I must say the zf is far easier to strip down most twin disc boxes have to be repaired by the dealers as there are too many service tools req. The I r m 220 is a great gearbox to 370hp.

 

[dustywings]

Dustywings

Why would you keep your boat in Hamble when you live in Lymington?? Its none of my business of course, just seemed an unusual choice, especially when the drive between the two can be pretty horrible traffic wise.

Simply cost I am afraid! LYH wanted £9k per year and where I am on the Hamble is £2k albeit a pontoon which is not walk ashore.

 

[Latestarter1]

It depends on what engine make, horse power range type of boat etc. I can say that zf are having a rough time at the moment over there 280 married to the d9 500hp engine as it only rated to 480hp the d9 torque curve is very steep and makes grinding paste of the gears. Volvo now use twin disc on the d9 , I must say the zf is far easier to strip down most twin disc boxes have to be repaired by the dealers as there are too many service tools req. The I r m 220 is a great gearbox to 370hp.

Now that is interesting CMD never permitted use of ZF 280 behind Cummins C let alone QSL 9 liter engine even at 350 Hp rating, it has to be big ZF311.........Somebody at VP screwed up!

Here is useful heads up I discovered. Upgrading boat from a pair of QSB 380/IRM 220A's to QSB 480's what do you do about the tranny? Replacing box is big cost as well as tearing up the installation to fit bigger box. You simply purchase lube pump for a 280 and pop it into the 220, goes straight in and works like a dream, have done it behind pair of Cummins 480's as well as Yanmar LYA2 440's. Proof that you CAN at least talk to guys at ZF, guys at MIT (U.K Twin Disc agents) are not at all helpful.