Optimax 225 External oil Hoses / Sender

[Nasher]

I've realised today that the hoses on the external Oil tank that was supplied with my 'pre-loved' 2003 225 Optimax have been cut down really short, @4'
I need about 10' I think.

The standard length supplied with the tank is 114", and can be purchased separately, but are @£75

I realise the supplied hose is special, in that it's a pair of hoses neatly joined together, but I'm sure there is nothing special about the spec other than that.

Does anyone know if that's a rash statement?
Are they special?
I know they are under pressure and obviously need to be oil resistant.

I'm planning on just buying fuel hose at the right diameter.

Also.
The remote tank has a float level sensor as part of one cap, and a couple of wires hanging out of it.

I wasn't planning on connecting up a separate gauge to the tank.
Can I assume that the low Oil level warning will be driven by a sender in the smaller tank under the main engine hood?

Or does the remote tank have to be connected electrically?
If so, where to under the hood?

Thanks

Nasher.

[neil.mccrirrick]

You will get a reading re how much oil in the external tank if connected. I believe low oil will come from the engine mounted tank

[Nasher]

Thanks Neil.
I want to avoid running more wires around the boat, so don't really want to connect the remote tank to a gauge.

I've searched a few US forums overnight and as usual found the whole range of answers on the hoses.

Considering the engine has a small tank under the hood, which is just topped up by the remote tank, and that small tank has an alarm, I think I'll take a chance on some good quality Oil resistant hose and keep an eye on the tank levels for a while.

Nasher.

[neil.mccrirrick]

The readout is on the tacho so no separate gauge needed. I think my external tank holds about 11 litres. Tends to use about 4 litres to around 200 litres of fuel if that helps although it clearly varies on load sea, state etc

[Nasher]

Thanks again Neil.

I've also discovered that the hoses are secured with special radiused cable ties which I'll order.

And stupidly I forgot to measure the hose which is on the boat away from my home.
Anyone know what size I need to order?

Thanks

Nasher.

[JimRib]

Just measured the hose from my 150 opti tank and it’s 6mm inside and 12mm outside. Mine is connected with standard cable ties and work fine just make sure you get them tight.
If you don’t connect the float switch in the tank you will get an alarm on the smartcraft

[Waterman]

I’d connect everything. The smartcraft system does not like it and could throw up faults and limp mode.

The sensor on the tank on the engine side is known to fail (magnet falls off) and it’s the whole oil bottle that needs changing, I changed mine this year.

[Nasher]

Thanks JimRib, that gives me a good start.
I know it's not reinforced - internal braiding - so I'll get a few meters on order.

Waterman, I believe you can chose in the menu not to have the external tank float switch connected, but might have a go anyway.
Where does it connect to at the engine?
Or does it connect at the gauge end?

[Nasher]

Waterman, I've noticed loads of internal Oil tanks for sale and wondered why.

Had better see if I can inspect the magnet on mine, but it's a little difficult with the engine laying on it's back on a(proper outboard) Pallet.
Oh, and with the tank full of Oil!
It will have to wait.

Do you know where the other end of the cable from the remote tank sender connects to?
I can't find it via Google.

Thanks

Nasher

[Waterman]

Originally Posted by Nasher

Waterman, I've noticed loads of internal Oil tanks for sale and wondered why.

Had better see if I can inspect the magnet on mine, but it's a little difficult with the engine laying on it's back on a(proper outboard) Pallet.
Oh, and with the tank full of Oil!
It will have to wait.

Do you know where the other end of the cable from the remote tank sender connects to?
I can't find it via Google.

Thanks

Nasher

Mine appears to go back towards engine but don’t know exactly where it connects to the smartcraft loom….? It’s only two cables so could easily be jumped.

I have a small lead with two male bullet connectors in my on board toolbox now as the engine mounted oil bottle sensor can be bypassed very simply if needed. Just unscrew the engine side bottle cap with engine running and ensure it starts to overflow, this is the test to show its being fed from remote bottle and the the procedure for commissioning the remote bottle and getting your new oil lines filled [emoji1303]

[Nasher]

Thanks Waterman.

I'm going to have to try and find somebody locally (Petersfield/Portsmouth) with a similar size and age Opti that I can go and takes some pictures and notes from.

Nasher.

[Jbooth]

Don’t be tempted to Hotwire the low oil sensor on the engine mounted oil tank if it’s faulty. someone had done this to my engine prior to me buying it. When the oil stopped transferring from the inboard tank to the reserve tank last year, I had no warning that the engine had been starved of oil. Spectacular engine seize at 5000 revs was the result.

[Waterman]

Agreed, Not a long term fix, but will get you out of a hole/home.

I lifted the cowling regularly to check the oil bottle and checked it was filling from the remote reservoir. Ordered the new bottle c/w the sensor and replaced ASAP.

Sorry to hear about your engine seizing [emoji51]

[Jbooth]

Had to replace the powerhead. I’m now having issues where my engine mounted reservoir is not filling with oil from the remote tank- and no obvious air leaks anywhere.. I’m going to replace the hoses and see if that makes a difference. Maybe a pin hole somewhere. The pressure output from the pulse valve on the crankcase seems so low that it wouldn’t take much to lose it through the system- on tickover you can barely feel the pressure if you put your thumb over the hose??

[Nasher]

Originally Posted by Jbooth

Don’t be tempted to Hotwire the low oil sensor on the engine mounted oil tank if it’s faulty..

Thanks Jbooth, it's not something I would consider doing.

I'm happy not to have a gauge on the large main tank which is easy to glance at every time I Open the jockey seat, but that tank under the hood is quite small and not something I'll be looking at on a regular basis during the course of a day out, so needs the warning to work.

Sorry to hear about your troubles by the way.

[Jbooth]

It’s been a steep optimax learning curve for me!
Once the oil / pressure hoses are changed hopefully the problem will be sorted!

[paintman]

No idea if this would be applicable to the Optimax 2-strokes but the earlier carbed Mercury - in my case Black Max 135hp V6 - have a bit of a reputation for the 2-stroke oil pump to fail resulting in engine seizure.

These older engines have a small tank on top of the engine which feeds oil to the petrol inlet pipe through a small pump driven off the crankshaft so mixes it with the fuel before it gets to the carbs.
This tank is replenished from the main remote tank which is pressurised from the crankcase to propel the oil to the small tank.
Mercury do a kit to do away with the oil pump - couple of bits of plastic for a few £s - and the advice is then to run it on 50:1 premix.
www.offshoremarineparts.com/68-14-25bk.html

[neil.mccrirrick]

Are the hoses connected to the external tank the right way round? If you swap them over them loosen the cap on the oil tank on the engine you will soon find out.

Start the engine and keep an eye on the oil level on the engine tank. It will quickly start to fill if all is ok. Cap back on quickly or oil will spill out

This is the right way to prime the system btw

[Jbooth]

Hi Neil
Thanks, I’m pretty sure they are on the right way. When I took the ducting off where all the hoses and cables run into the engine cowl, there was a lot of oil pooled in the ducting. Im thinking there may be a leak in the hose? I was surprised about how little pressure comes from the crankcase- virtually couldn’t feel anything coming from the hose. But that was on tickover- would probably increase with some revs.

[Nasher]

Originally Posted by Jbooth

I was surprised about how little pressure comes from the crankcase- virtually couldn’t feel anything coming from the hose. But that was on tickover- would probably increase with some revs.

I've just had a flick through the Genuine workshop manual I have for the 225 Opti, and although the Oil injection system is obviously covered at length, including how to bleed the remote tank hoses, I can't find any data or test to see what pressure is being provided to the remote tank to force oil from it to the under-hood tank.