PDA

View Full Version : Mercury Optimax 150



Whitehunter
11-02-2010, 08:35 PM
I have a Mercury Optimax 150 2004
Had the issue of alternator vibrating and shearing bolts fix this isue with slight mod.
Had to be tow back on the weekend with the bolt shearing off the bottom of compressor unit inturn breaking the top two bolt casts.
dead in the water, up for a new compressor unit now.

Has any body else had these problems only done 398 hrs

cormorant
11-02-2010, 09:17 PM
Here is the 135 hp bolt issues


http://www.ausfish.com.au/vforum/showthread.php?t=159884&highlight=optimax

Angla
11-02-2010, 09:47 PM
I feel for you. If you ask Mercury about it they will admit to knowing about 6 bolts breaking and they don't think it is a problem. Personally I think it is just a matter of time before it happens to this version of our motors.
I believe they have been modified in this area on later models and hopefully the problem does not exist for these newer motors.

Do you have any photos to show the damaged areas?

Keep us appraised of your discussions with Mercury and I hope it is not too expensive for you

I believe I was very lucky to be able to just replace a broken bolt with a better one.

Do you think I am still susceptible to bolts breaking from the compressor in the future?

Cheers
Chris

OWorld
12-02-2010, 08:41 AM
Hi again Whitehunter,

I am not 100% sure on this one as I have not really heard from you the whole story from the beginning, but a few comments I can make here .....

I feel that for the bolts (Alternator or Compressor) to shear, there must have been a probem in the first place. An unusual vibration or failure. As I aid earlier, it could have been the belt tensioner, or something else. As far as the compressor goes, have you been replacing once a year the Air Filter? This is a quite crucial and inexpensive spare that needs doing in order to keep the compressor running cool. If that filter looses is airflow, the compressor will overheat and fail and once it does the bolt will snap off, as the pressure applied through the belt from the flywheel would be simply too great.

In conclusion, if the bolts had failed the compressor should still be usable. But if the Compressor fails, than the bolt could easily snap! How log after the Alternator bolt issue did you experience he compressor one?

Opti

trueblue
12-02-2010, 12:33 PM
makes me really wonder about the Opti's compared to a 4 stroke

Noelm
12-02-2010, 01:25 PM
makes no difference what brand or operating principal you have, problems can and do arise, it's how you are looked after that matters, only have to look at the clean, green Toyota Prius, currently undergoing a recall (and its a 4 stroke and electric)

Whitehunter
12-02-2010, 01:33 PM
I put the motor in every 50 hrs for a service as here in Bundaberg we do quite afew nm out to sea and I insist that everthing is done at no expence spared.

I only use qualified service personal as my life depends on it
Whitehunter

OWorld
12-02-2010, 05:38 PM
Whitehunter,

It really sounds like you are doing the right thing, unfortunately though, I also get the impression that "maybe" you should start questioning the know how level of your optimax technicians over there.

I have had a good chat about this issue with my US Pro Technicians and there are some interesting developments for the very early Optis from 97-98, but definetely not something you should have suffered.

As a matter of curiosity, in your almost 400 hours done, how many Belts have you had replaced??? I would recommend one every 200 hours at the very least! Sure, you might do 500 with one if you are lucky! but if you were my client and you would say to me, no expense spared, I would do a new belt every 100-150 hours. It is another $50 component less to go wrong. And on a Optimax, a really crucial one, in particular if you only have one engine!

Look for my reply next week in the other thread.

Take care mate,
Opti

death_ship
12-02-2010, 07:37 PM
makes no difference what brand or operating principal you have, problems can and do arise, it's how you are looked after that matters, only have to look at the clean, green Toyota Prius, currently undergoing a recall (and its a 4 stroke and electric)
and the problem is the accelerator pedal

krill
12-02-2010, 09:03 PM
As a matter of curiosity, in your almost 400 hours done, how many Belts have you had replaced??? I would recommend one every 200 hours at the very least! Sure, you might do 500 with one if you are lucky! but if you were my client and you would say to me, no expense spared, I would do a new belt every 100-150 hours. It is another $50 component less to go wrong. And on a Optimax, a really crucial one, in particular if you only have one engine! What is the Mercury recommended interval on the belt?

John_R
13-02-2010, 05:23 AM
I have an 03 Opti 150. No issues yet.

Whitehunter - what is the slight mod to fix the alternator bolt issue?

soulfish
13-02-2010, 06:38 AM
white hunter i had a pair of 150 03 model optis & both sheard bolts.My neighber has an 03 & a couple of weeks ago he sheard his altinator bolt.Seems a very common thing in that model i have heard of a few,i think on ausfish a fair while back.Mine had around 450hrs at the time

John_R
13-02-2010, 07:15 AM
There are two different but related issues here.

First is the alternator bolt that holds the two piece bracket onto the motor and is not supported at the top.

The second is the air compressor mounting bolts coming loose and breaking. I reckon any extra vibration from a loose compressor might contribute to a broken alternator bolt.

My 03 Opti 150 has 460 hours on it. The dealer checked the alternator bolt and said it was fine. They also tightened the compressor mount bolts.

I am going to replace the alternator bolt ASAP.

Noelm
13-02-2010, 07:21 AM
and the problem is the accelerator pedal
correct, and this is a problem with an alternator bolt, nothing to do with being a two stroke, that's the point. the people need advice and help, not a mine's bigger than yours debate (AGAIN)

Angla
13-02-2010, 07:45 AM
There are two different but related issues here.

First is the alternator bolt that holds the two piece bracket onto the motor and is not supported at the top.

The second is the air compressor mounting bolts coming loose and breaking. I reckon any extra vibration from a loose compressor might contribute to a broken alternator bolt.

My 03 Opti 150 has 460 hours on it. The dealer checked the alternator bolt and said it was fine. They also tightened the compressor mount bolts.

I am going to replace the alternator bolt ASAP.

WISE CHOICE Make sure the new one is rated tensile

Cheers
Chris

OWorld
13-02-2010, 02:12 PM
You see guys,

Tightening the bolt will actually break the Loctite seal!!!

And I am starting to see a dangerous pattern here ...... Technicians that do not replace the Belt on the recommended hours (apparently 100) and instead of removing, reapplying correct loctite, and re-torquing to specs, they are simply tightening the bolt and in so doing they are actually damaging the loctite seal and causing the problem.

Hopefully I am wrong in my assumptions but please read my reply in the other thread for my final comments and conclusions on this issue.

Opti

cormorant
13-02-2010, 08:34 PM
Yeah I was going to ask which loctite was able to be retensioned and is that being used? I don't know of the product but they have a large range

OWorld
13-02-2010, 10:19 PM
I would use the following logic:

1. Clean bolt threads with Loctite 7649 Primer (92-809824).
2. Apply Loctite 271 to bolt threads and torque bolts to
---------- Alternator Bolt -------------------- 40.0 Ib. ft. (54 Nm)
---------- Compressor Top 2 Bolts -------- 41.5 Ib. ft. (56 Nm)

This is all,
Opti

John_R
14-02-2010, 06:25 AM
The problem with the alternator bolt is not due to it coming loose. It is most likely breaking due to work hardening and stress focus on the thread. Extra vibration from a loose compressor would no doubt aggravate this issue.

I don't know if the dealer re-loctited the compressor bolts. Somehow I doubt it. And yes simply re-tightening them would break the loctite seal and they will come loose again. I will get some loctite.

OWorld
14-02-2010, 08:18 AM
Hi John,

As I said earlier, I am guessing here. I agree with you, it might not be that the bolt is coming lose, but it is another possibility that you are avoiding.

Another important thing ....... As part of routine inspection, it is a good idea to lift off the flywheel cover assembly to inspect for signs of the belt rubbing on the underside of the cover. I have seen a few where the belt dug right into the plastic and this is a good indication of a problem with the belt alignment which could be do to a bad pulley, or loose alternator or compressor mount.

Opti