2005 Mercury Optimax Overheat

[wineloon]

I had a severe overheat on my Optimax 135 and was looking to get some advice from anyone that can give any!

I was at a remote lake and had the alarm go off about 2 miles from the marina. I stopped and let the motor cool off. It was late in the day and I decided to just fish at the spot where I stopped so that the motor could cool down. The sun was going down and I decided to call it a day. I started up the motor and got about 3/4 of a mile back when I had the alarm go off again. I slowed the boat RPM down but could not get the motor to cool down. I had a strong headwind and had just a mile to go to the marina. I tried to limp back on my trolling motor but to no avail. My only option was to run with my Optimax back to the marina. The motor went into guardian mode and I continued on for another 4-5 minutes until the motor stopped and I was stranded.

So I spent the night on the lake in 40 degree temps with no overnight gear. I was able to find a tow back to the marina early the next day.

I got back and immediately took the boat to the shop that I purchased it from. They informed me that Mercury does not cover overheat damage in its warranty and that my motor was going to cost $11k to repair. They told me the best thing to do would be to replace it. Their quote to replace the motor was $10k (including a clause that said they would be able to hold onto my old motor)

I asked one of the mechanics that worked there if he ran any tests on the motor. He said he ran a leakdown and a compression test, both of which checked out fine according to him.

I then took the motor to a second shop who gave me a printout of the diagnostics. Here are the problems that came up on the report.

1. Oil Level Sensor Circuit High
2. Oil Level (engine) is low
3. STBD Head/ECT Overheat
4. Air Compressor Overheat
5. Overspeed in Neutral
6. Oil Pump Output

According to the diagnostics, at 64.23 hours both my port and starboard ECT's had a reading of 352 degrees. My IAT was at 208 degrees.

At 64.28 hours, my temp readings were 79 and 80 degrees in either head and 79 on the IAT.

I don't know what could cause such a rapid drop in temperature in such a short period of time??


So the second shop told me that the motor was most likely blown due to the extremely high temperatures that the motor had run at.

I took the motor home and started to take it apart to see if there was anything visibly wrong with the motor. The pistons and cylinder walls were not damaged at all. Nothing on the motor showed any signs of heat damage. I could turn the flywheel and my pistons went up and down without a problem. Almost everything looked fine to me but I am wondering what else to check?

The only problem I found while taking apart the motor were the head bolts on the port head were loose when I took off the head. I am guessing that the motor got so hot it expanded the head and then as it cooled it retracted leaving the bolts loose.

The heads appear to be warp free but I will need more accurate tools to know for sure I imagine.

My question is this....
Should I attempt to fix this motor or should I just toss it?
Mechanically it looks good but I honestly am unsure when it comes to outboards.
Are there any tests I can run to see what components might be damaged? Does the ECU need to be reset so that I can possibly start it up again?
Is it possible that the compressor went out causing the motor to stop before any major block damage was done?

Any ideas or suggestions would be great.

 

[wineloon]

Re: 2005 Mercury Optimax Overheat

bump

 

[BPSJ1]

Re: 2005 Mercury Optimax Overheat

Good luck finding any help on here... posted a simple problem yesterday and still only 1 post in response. Wish I knew more to help you but I am in the same " boat " you are, not a marine mechanic.......

Edit: 150,000 people have found that this is a wonderful place, with good technical info, and good friendly people . . . QC

 

[joed]

Re: 2005 Mercury Optimax Overheat

I'm no expert but the first thing I would do is a compression check on each cylinder.

 

[wineloon]

Re: 2005 Mercury Optimax Overheat

Compression check came out fine according to the mechanics at the shop where I took it.

 

[Expidia]

Re: 2005 Mercury Optimax Overheat

Hang in there. Someone will respond. Many of the regulars I would think are outside getting their rigs ready for the new season.

It's going to be in the 80's around here sat and sun. Who wants to talk boat, when we can be in our boats

You might try to ask this same question over at another site I frequent that is a little more O/B repair oriented. It's called Thehulltruth.com

Since your question is very motor specific. You need to hear back from someone who knows motors especially the Opti!

 

[joed]

Re: 2005 Mercury Optimax Overheat

Hang in there. Someone will respond. Many of the regulars I would think are outside getting their rigs ready for the new season.

It's going to be in the 80's around here sat and sun. Who wants to talk boat, when we can be in our boats

You might try to ask this same question over at another site I frequent that is a little more O/B repair oriented. It's called THe hulltruth.com

Since your question is very motor specific. You need to hear back from someone who knows motors especially the Opti!

Hulltruth.com is nothing to do with boating. It is some sort of search engine.

Ok you meant
http://www.thehulltruth.com/

 

[wineloon]

Re: 2005 Mercury Optimax Overheat

I'll check over there too but that doesn't mean that the smart guys here can get lazy!!!
Thanks for your replies guys.

 

[Bob_VT]

Re: 2005 Mercury Optimax Overheat

I had an older 6 cylinger mariner 150 that cooked due to the oil injector pump. Same dam alarm as the overheat and I had a water pressure gauge. I thought the alarm went haywire because I checked the head and it was not hot.

Little did I know about the oil alarm..... and I had plenty of oil in the tank. That "glitch" scored two pistons and locked it up. Following the head rebuild I tossed the oil injection and went pre-mix. The oil injucteion pump was a cheap plastic gear.

 

[Expidia]

Re: 2005 Mercury Optimax Overheat

Hulltruth.com is nothing to do with boating. It is some sort of search engine.

Ok you meant
http://www.thehulltruth.com/

Oops, sorry I corrected it in my above post.

Check the boating forum at the thehulltruth.com (mostly salt water boaters) There are over 1 million posts, so it's a very active forum with many knowledgeable people. Not as friendly as this forum so don't get sarcastic or they will rip you a new one

I'm just wondering if you didn't get much feedback here because the warning signals went off and you drove it anyway. Probably a good reason to get a small kicker as a back up. I know the predicament you were in but you got on the boat ill equipped for an emergency (like warmer clothes if you broke down or the weather turned).

But the worst to me was continuing to drive it. Did you not have a cellphone to call for help? or a VHS, fixed or handheld?

Driving in an overheat condition to me is like getting the warning light on your dash in your car and you continued to drive to the repair shop and the motor seized up and then you want the manufacturer to cover it?

I'm not trying to be a **** here, it's just you did a bunch of things wrong here and your plight is just what we as members try to share our boating experiences and hopefully we can avoid your types of mistakes.

Now from your debacle, I know if a light comes on I shut it down and use my VHS to get a tow. Or at least my cellphone to call home and have someone send help.

That had to really blow spending the night all alone and with no proper cloths in April! Don't know what region you are in cause it's not listed. Fl is one thing, the Northeast is another, it was 32 here a few nights ago. Here you could have died!

I keep a ditch bag on board with a portable handheld and warmer clothes. I learned that from this forum. I also learned the hard way that the portable has less than a 5 mile range (closer to 2 miles). First time I got stranded, it was useless. So I bought a fixed mount VHS with an 8 foot antenna, just for the times when my Merc might fail!

Let me know if the other site helps you. Most of the questions you were asking (unless someone posts back that really knows O/B's) seemed pretty techy for this site in my opinion.

Good luck and sorry to hear about your ordeal.

 

[wineloon]

Re: 2005 Mercury Optimax Overheat

Well I learned my lesson the hard way.

To be honest I didn't know the buzzer was an overheat alarm at the time. If I had known, I would of shut it down. But that is just the plight of being a new boat owner. I have boated for my entire childhood but never with an outboard motor or on a boat that has almost no gauges. Now I know and a lesson is learned. I am only 26 so I still have many more mistakes to make. Hopefully not as costly as this one.
The dealership that sold me the boat should have let me know all the mechanical details on the outboard so this wouldn't have happened...

This happened back in January at Apache Lake here in Arizona. Temps are not as bad but it did get nippy. It is an hour long dirt road to the middle of no where. No cell phone reception and the "marina" is more along the lines of a boat ramp.

Hopefully I can get some ideas on what to do with this motor. I want to get the boat running again and am just completely sick about this whole ordeal. I feel like boat mechanics are more profiteering and cockeyed than regular mechanics! It shouldn't have to be so damn hard and expensive to get this motor running right again.

I thought I was prepared. I have a fixed VHF radio (no one responded when I hailed channel 16), Flare Gun, First Aid Kit, GPS, extra prop and hub kit, tool kit, water, etc.
Now I am going to make a "overnight kit" so that I can survive the night if need be.

Thanks again for the insight and I'll update if I find anything out.

 

[Expidia]

Re: 2005 Mercury Optimax Overheat

Put a couple bottles of water and some granola bars in that ditch bag too.

The other thing you could have done if you are going on a remote lake is to file an itinerary with someone (let them know where you are going) they could have driven up to where your car would have been and they could have called the police. Just like pilots file flight plans.

I run with a 36 lb Minn Kota for fishing and it's a decent back up since it gives me the extra trolling battery and I could get a little more distance with the starter battery to limp back to the dock. Pretty cheap insurance. Pick up a used one.

Other than that it sounds like you had the right gear, except for the clothing.

A girlfriend might have been another handy item to have brought along that could have kept you warm

Good Luck with the repair!