… for the Max from your sailing!

Technical

Read about technical aspects discovered by our members. Note some articles may appear under more than one category.

Volvo MD2030 Exhaust Riser/Elbow

Does your engine suffer from lack of power, unable to obtain maximum revs?

We bought a “pre owned” Maxi 1100 – “Maxi Magic” from SD Marine. Whilst she is a very quick boat under sail, the same could not be said when she was motoring. Having sailed through most of the boats out in Poole Bay, we then suffered the embarrassment of them overtaking us when under power coming back into Poole harbour. Something had to be done to restore our credibility!

We had noticed that we could only get a maximum of 2800 RPM out of the engine under load, where as on our previous boat, a Maxi 34 “Eye of Horus” we could get 3400 RPM. The difference in RPM was initially put down to only having a two bladed fixed prop on the 34 as opposed to the three bladed folding on the 1100 and an extra two tons weight difference. Based on our engine experience with the Maxi 34, I took the opportunity in the autumn to remove/inspect the exhaust riser. Having removed the riser it was no surprise to find that approximately 1/3rd of the inner sleeve (where the raw water mixes with the exhaust gas) had corroded away and the main bore had been reduced from 35mm diameter to 7mm diameter (see photo – just enough to get a pencil through!) by the build up of carbon and salt.

                                         

Inlet-Old unit with pencil sized opening                         New unit with 35mm bore

3 exhaust manifold riser outlet                4 exhaust manifold riser outlet

Outlet-Old unit with corroded water gallery                        New unit

In my opinion there is no point in trying to salvage a riser in this state so it was off to the local Volvo agents for a new one (£160 plus £4 for the gasket). (Looking around the internet I did not find any at a materially better price). If you do try and clean/salvage an exhaust riser be very careful of the inner sleeve/water gallery, as although it may be intact, it will probably be rotten and will break up if any force is applied to it.

5 exhaust manifold riser outside          6 exhaust manifold riser outside

Outside View Old unit does not look so bad from the outside!

Having fitted the new exhaust riser we took her out for a sea trial and at full throttle got 3350 RPM. That should be enough to see off the other boats motoring back into Poole Harbour!

On a more serious note, I would recommend that you check the exhaust riser after say 600/700 engine hours (Maxi Magic had done 1100 hours). I considered getting a stainless steel riser fabricated, however, apart from the estimated cost (£250), talking to other people about their experiences with stainless risers, the sulphur in the exhaust corrodes the stainless and stainless cannot absorb the thermal shock (cold sea water and hot exhaust gas) as well as cast iron. Also when stainless cracks you will get a hole whereas cast iron will tend to weep.

Removing the exhaust hose from the riser is a bit of a chore. I used a blunt screw driver and gradually worked it into the joint, taking care not to tear the rubber pipe, and it took about 30 minutes to release. To make it easier to remove the hose in the future, I wrapped the outlet of the new riser in PTFE tape.

Having checked our fuel consumption, this has improved, and the tiny bit of hunting that we had at tick over has now gone. A job well worth doing.

Rob Ware – Maxi Magic

 

 

Article submitted by Darrel Walters – Maxi 38+ ‘Carpe Diem’

I wanted to put pen to paper and let others know there is a life after Ardic Heating systems.

People who own Maxi’s yachts know all to well that Ardic are no more and that there is only one company left in the Uk that you can get Ardic Spares from. I called them a week or so ago because my fan blower in my Ardic heater was making funny noises. I did back in 2009 replace said fan so I was quite surprised to think it was on its way out again after, well lets be honest know more than 100 hours worth of work. The water pump was also making noises, So asking the company for a price for both parts came to around £600.00 I know full well the parts are not worth that and I hate it when I feel I am held to ransom because of the supply and demand of said products drive the price instead of the true value.

This sort of price, you start to think if it may be worth just upgrading the whole system to something newer. Getting some prices from said company, about upgrading the diesel heater and the water heater to a dual element system, updating the blower for one more efficient and your not seeing much change out of around £4K. Continue reading

Judging by the articles on the MoA website and the Web, it appears generally acknowledged that the Ardic heater which as installed by Nimbus, is less than effective at heating the cabins.  We had the heater unit serviced last winter by the local agent and whilst resolved the sooty deposits on the stern, the heating was no better.  It appears that in pre heating the engine, heat the fresh water and the cabin is beyond the capabilities of the system unless also running the engine.  The basic problem is that the system initially heats the cast iron mass of the engine which I believe takes 3kW, therefore the temperature of the air to the cabin is cool to say the least.  The pipework diagram in the manual suggests that this should not be the case, but on a cold day working on the engine with the heating on, the engine was starting heating up but the cabin was not.

Continue reading

Maxi 1100 “Second Rebellion”

 

Navigation electronics, a cost effective option to having GPS plotters at both the navigation table and at the helm

 

The 2001 yacht was purchased in August 2008 and it came with a Raymarine RC530 colour plotter at the chart table, a Raytheon RL70 at the helm and a Seatalk interface which integrated the radar.  Unfortunately the helm plotter was not readable in daylight, so something had to be done.

 

  • As the yacht had the seatalk interface and all other instruments/radar were Raymarine, we only considered that manufacturer’s equipment.
  • We established that the radar scanner would be compatible with the current Raymarine E80 range of plotters and we could also have AIS, however the E80 equipment would not interface with the RC530 existing plotter.
  • The obvious but expensive option was to replace both plotters.  However, Raymarine in common with other manufacturers, do not market a repeater for the plotter, you just buy 2 of them at around £2k each.
  • However with the help of a friendly engineer in the local agent, it was revealed that you did not need a second plotter.  An E80 (or E120) at the helm with a VGA cable to an inexpensive LCD computer screen (they are all 12volt), can be used to feed the screen at the chart table linked with a Raymarine keyboard, which they market for the huge screens on power boats.  This option is actually better than 2 E80’s, as the PC screen can be larger and as in ours in “letter format”, which is ideal for split screen plotter/data/radar viewing.  I believe that the latest “C” series plotters may also have the repeater facility.
  • As it happened we had a spare PC screen so it cost us nothing, the screen swivel mount cost about £20 and the quite neat keyboard was £300 plus VAT, quite a saving on £2k and a better option all round.
  • All E80 functions can be duplicated below using the keyboard and the PC screen can be swivelled to the saloon to entertain the grandchildren with DVD’s (from a player) with surround sound through the boat audio system.
  • The only downside is that manipulating the data from the chart table, also changes the plotter screen at the helm.
  • Both old plotters found a ready market on E-Bay, to help offset the cost of the new equipment.

 

The system has been extensively used for 3 seasons over 5knm without problems and a recent comment from the local agent for Raymarine was “I don’t know why more people don’t go this route”.  I do…they just do not know the option is available.

 

Jim & Eric Sey

 

Pics:

  1. Nav. station, Mount, and Keyboard in use

 

  1. Keyboard parked