Optimax 250 ProXS

[nNed]

<1B861587>

Good morning. I have a Optimax 250 ProXS. It is a 2010 with 160 hours on it. Several months ago I started to struggle on take-off (RPMs will not come up) sounds like it is either not getting fuel or flooding. It will continue to run at that low RPM for as long as you want it too without shutting down. If I start to "feather" the throttle, about half the time the RPMs will come up, the boat takes off and runs great. Here are the things that have been done to correct it at my local marine repair. 1) replaced the computer to the key pad 2) replaced the battery with largest Optima 3) changed the spark plugs 4) changed the fuel filter 5) Replaced the small oil reservoir on the engine. None of this has corrected it. The technician said there were always multiple "fault codes". On Sunday I took it out to see if the last repairs corrected the issue... it did not. There was one error code that popped up. It said "low oil starboard tank". But the tank was completely full. Is the issue some sensor in the main oil reservoir and the engine computer is holding it back, seem strange since most of the time I can feather the throttle and it will take off.

One additional note... at the Marine Repair shop, when they put it in the tank and ran it they had a difficult time getting it to replicate the issue. However, it does it every time on the lake. Is it something to do with the angle the boat is at... in the tank it is on the trailer and the angle does not change but on the water the front end comes up. It also seems to almost flood out when in reverse.

Other observations - engine starts immediately, idles great, sounds normal.

I would really appreciate any advice.

[EuropeanAM]

Moving your thread to the 3L Mercury forum for you. Please be sure to provide your Serial Number when you respond (required when posting).

Are you getting any warning horns?

[nNed]

Good afternoon. Engine Serial Number = 1B861587 Engine Model # = 1251P73ED

This week when I ran it, I did not get any warning horns. The Smart Craft did show an alarm flashing "AL". It said "low oil starboard tank".

[EuropeanAM]

Go to Settings-Tanks and see if perhaps the Tank-2 is set up as an oil tank.

If it is, verify that you have two wires attached to the REMOTE oil tank cap (same cap that hoses attach to).

[nNed]

Tank # 2 is set up as an oil tank. Tank # 1 says "Not Connected". Also the Smart Craft show the oil tank capacity is 3 gallons.... It does not look like 3 gallons to me....

The main oil tank, in the battery compartment of the boat, has 2 lids. The lid on the left has a large black hose running from it and the lid on the right has a 2 small hoses running from it. One of these small hoses has a "blue" stripe on it. Neither of the two have any electrical wires running too them.

[SilverFox579]

If the cap with the hoses on it doesn't have two wires like pictured below you do not have ability to monitor remote oil tank level...

tank.jpg

[JOE54]

tank in FOXES pic is 3 gal tank for ref

[nNed]

Good morning. My tank is a little different. On the cap that has the 2 smaller hoses, there are no wire leads coming from there and I can't find any place that 2 lead wires would plug into. As well on the other side of Silver Fox's tank, the opposite lid, my tank has a large hose (maybe 1.5" diameter) coming from the cap and back to towards the engine. Not sure what the purpose of the large hose is? Any ideas?

[Another Distraction]

It's the oil fill hose.

[SilverFox579]

Good morning. My tank is a little different. On the cap that has the 2 smaller hoses, there are no wire leads coming from there and I can't find any place that 2 lead wires would plug into. As well on the other side of Silver Fox's tank, the opposite lid, my tank has a large hose (maybe 1.5" diameter) coming from the cap and back to towards the engine. Not sure what the purpose of the large hose is? Any ideas?

The standard cap does not have wire terminals, just nipples to connect oil hoses. When a tank is upgraded to monitor remote tank level, the kit includes a new cap with float assembly and terminals for the fuel/oil/speed harness. The large diameter hose on your fill cap is for the deck fill option which I don't have.

As Joe mentioned, mine is indeed a 3gal tank.

[EuropeanAM]

You don't have the sender or the harness in your remote oil tank.

On your MercMonitor, go to: Settings - Tanks - Tank-2 (change to "Not Installed", Save, and then exit back to home screen).

This will resolve the "Smartcraft only Low Oil Level" (with no associated warning horn).

[nNed]

Got it... I should have realized it was the fill hose... too early in the morning when I went out there and not enough coffee. So if I don't have the float switch and the cap with the nipples for the wire leads..... then do I 1) go in the Smart Craft and cut off the "Oil tank Sensor". But how could that be causing my main issue which is difficult to get the RPMs up at take off?? 2) maybe my Smart Craft is getting it's data from the small oil reservoir that is on the side of the engine... (If I recall correctly there are 2 wires running from that cap).

[nNed]

Thanks everyone!!! I have first tournament of the year this weekend. Will let you guys know how it turns out.

[EuropeanAM]

Instructions provided about will resolve the fault displayed for Low Oil Level (Starboard), with no warning horn.

For the other (acceleration) problem, IF there are absolutely no faults occurring it might be a good idea to to try the following:

1. Check belt/tensioner (use an INCH LBS Torque Wrench, set to 70 lbs/in... it should click before tensioner hits the end of it's range).

2. Try a known-good MAP sensor.

[nNed]

Good morning. EuropeanAM was right, I turned off the "Starboard Oil Tank" in the Smart Craft and sure enough... the screen did not get an alarm condition all weekend. Regarding the "slow start \ bogging down \ sputtering on take-off". The problem was still there all weekend. Every time I can get it to eventually take off but it takes some feathering of the hot foot. But once the RPM's come up, it runs great. Today I will start looking for a new MAP Sensor and follow that advice as well. On a positive note I did finish first in the tournament this weekend.

Anyone know the part number of the MAP sensor for my engine?

[JOE54]

may have a fuel psi problem at low rpm

[EuropeanAM]

854445

You might consider seeing if a friend will let you borrow one for a short period, though.

And Joe's spot on in regards to fuel pressure (or air pressure).

[Another Distraction]

Would Low fuel pressure at low RPM's be a compressor/tentioner issue?

[JOE54]

highly unlikely

[EuropeanAM]

Would Low fuel pressure at low RPM's be a compressor/tentioner issue?

Weak or broken spring on the tensioner may provide enough tension to start/idle, but will allow the belt to slip when you attempt to accelerate.

Easy check with an INCH LBS torque wrench, set to 70 lbs/in (should click BEFORE the tensioner reaches the end of it's travel).