Engine Talk

[Mikey B]

With the boat out of the water due to the inclement weather I decided to see if it was possible fit a water temperature gauge and sender unit to my Yamaha F30.

 

I started by looking at the Yamaha spares list to see if one was available.

 

BHG marine supplied me with a conversion kit which contains all the parts necessary to complete the job.

 

After isolating the battery the first job was to remove a 17mm blanking plug from the port site of the motor.

 

The plug is fitted in the water jacket just above the thermostat housing.

 

The new sender unit complete with its pre wired cable was then, with a dab of grease and a new copper washer, fitted in the thread in place of the blanking plug.

 

Next job is to run the 2 core cable from the outboard to the helm.

 

This was done by running the cable along the Teleflex cable and then through the cable route provided on the starboard side of my Orkney 520, past the control box to chosen location on the helm.

 

A 52mm hole was the cut in fibreglass adjacent to the steering wheel assuring a clear view of the gauge.

 

The gauge itself has 5 wires; all are colour coded to match the colours on the Yamaha multi function unit.

 

All cables were cut to length and with the connectors provided in the kit connected to the multifunction unit wiring.

 

A cable for the gauge back lighting was then fitted to the fused side of the navigation light switch.

 

With all the cable connections checked and secured out of harms way with cable ties, the battery was reconnected.

 

The biggest and by far the most difficult job was routing and concealing the cable from the outboard to the helm.

 

The wiring was a piece of cake being pre wired.

 

One thing of note - when I removed the 17mm plug from the thermostat housing; the area around the thermostat was completely blocked with salt crystals.

 

On further investigation I found the thermostat which is made of copper to be completely encrusted with salt crystals.

 

Simply washing under the tap removed the crystals.

 

Even though the motor is washed through religiously after each trip it obviously leaves salt water in the thermostat housing leading to the corrosion.

 

I will be checking this regularly from now on.

 

Installation took approximately 6 hours including cleaning the salt from the thermostat and housing.

 

 

Mikey B

 

[rich]

Mikey,

 

Useful information for those of us with Yamahas and 520's. Something I am considering fitting. How much did the kit cost?

The temperature gauge should give an indication if the water inlet gets blocked by a plastic bag or similar or if the pump impeller is getting worn. Is it visual only or does it sound an alarm?

Despite having the gauge fitted I would still recommend you keep your eye on the water discharge at regular intervals as a matter of habit. If no cooling water is present it can take a while for a temperature sender to respond as there will be no heat transfer medium (water) between the block and the sender.

Interested to read your comments about the build up of salt crystals around the thermostat. How are you flushing the engine?

In the handbook they tell you to connect a garden hose to a connection below the cowling and flush for 15 minutes without the engine running. This would not open the thermostat.

Personally I use "ear muffs" over the water inlet on the outboard leg.

I can then run the engine up to temperature which in turn opens the thermostat and this should clear away any salt crystals the other side of the thermostat.

My engine has done very few hours, but I shall make a point of removing the bung you talk about after a few more hours and see if my engine has a similar build up.

 

Rich (S)

 

 

 

 

 

[Bob F]

Nicely constructed post, Mikey. Concise, clear and to the point.

 

BF

[rich]

P.S.

If anyone is looking to install additional instruments in their facia, I may have the correct size hole cutter you require. 52 mm dia. included. May save you buying one to use just once, or save drilling loads of holes and filing to suit.

PM me if you ever need one.

 

Rich (S)

[Mikey B]

Hello Rich thanks for the reply.

 

My F30 has now done 160 hours; I service it myself in accordance with the manufactures specifications now it

[rich]

Mikey,

 

You say that the owners manual states that it is not necessary to run the motor with the hose pipe attachment fitted to the side of the motor.

In my handbook it states in bold letters " CAUTION Do not perform this procedure while the engine is running. The water pump may be damaged and severe damage from overheating can result"

I believe the only way you can run the engine whilst flushing is to either have the leg standing in a barrel of water with the level of water above the cavitation plate, or by using a set of ear muffs as I have been doing.

Try giving BHG a call and ask to speak to Steve in the workshop. I am sure he can advise.

Please let us know the results as there are several members with Yamaha motors who I am sure are interested in the correct procedure,

 

Rich (S)

[Mikey B]

Having contacted BHG Marine, I have a result regarding flushing out of my F30.

 

Yamaha fit the cold water flushing connection on the side of the motor for owners who are unable to flush the motor with flushing muffs due to noise restrictions or keeping the boat on the water.

 

They recommend the motor be flushed while running at idle with a set of intake muffs fitted.

 

This will allow the thermostat to open so flushing out both sides of the stat pocket.

 

They also recommend removing the thermostat for inspection and cleaning as a matter of course during periodic maintenance (at the same frequency as the oil changes).

 

Failure to clean the thermostat could lead to premature failure of the cooling system and result in damage to the engine.

 

 

 

Mikey B