F150 - Exhaust Guide change - Photos, tips and question

[FrenchFry]

I have been a bit misleaded by the mechanics that sold me the engine, they did not foresee to change some gaskets and apparently feigned to see an important issue, so in order for people not to have the same problems, here are some tips and photo to change the exhaust guide, which is probably one of the worse part to change:

- remove the oil level guide
- remove the big bolts and remove the powerhead
- remove the inverter
- remove the 4 bolts, remove the bottom cowling
- remove the 4 bolts on the silent blocks up and down
- remove the upper casing
- remove the bolts and extract the gas exhaust
- remove everything that is linked to the exhaust guide, especially the 4 bolts in the oil tank attaching the manifold

See the pictures.

Now of course there is a problem, see the two last pictures, the exhaust gas on top of the exhaust guide is completely corroded (how comes this is so corroded? What is Yamaha doing?), which would mean to change the entire cranckcase, what should I do with this and can it be repaired?

 

[FrenchFry]

So, no magical or palliative solution for the corroded part?

Is this a kind of programmed obsolescence from Yamaha? My old engine is very far from having this level of corrosion.

 

[schematic]

poor anti-corrosion coating. Check with Yamaha. There may be a kit for this engine size at a reduced price as there is for the larger engine size.

 

[FrenchFry]

Do you have some examples of those kits (links)? For that one I don't see another solution than changing the whole powerhead crankcase...

 

[schematic]

That certainly is a good example of dry exhaust corrosion. The kits available are for larger engines with exhaust component failure. Not so much for block failure. If it was me, I would "Tig" the gasket surface and hope there are no other perforations. Might get you a few more years....What a shame...Might want to premix your fuel to add a little oil to the exhaust. (might slow down the corrosion)

 

[FrenchFry]

Yes, what a shame, the rest of the engine is clean (except the parts under the exhaust guide, strangely corroded too but not to the extent of the powerhead).

Whatever could have caused this (internal anodes not changed?) cannot explain why this happened, for me this is a Yamaha issue, and probably this is my last Yam outboard, this engine was well maintained by Yam dealers, assuming the mechanics did the job correctly, but even if the contrary occured this still cannot explain this level of corrosion, my 1990's former Yam engine has not even a single sign of such corrosion.

Discussing to get another engine block with the guys that sold it, in the meantime I did put a joint for exhaust repair, not sure I would dare to post a picture of this stuff here, not sure either if this will hold, but no choice...

 

[FrenchFry]

No Title

The "repair", still wondering what could have caused such corrosion.

 

[99yam40]

Different parts or did you repair it(weld and machine)?

 

[FrenchFry]

No Title

No, same part, I put Holts Gun Gum on the corroded exhaust, see the difference on the picture, I tried to follow the form of the gasket and of the exhaust guide that I have changed, not sure it will hold, we will see, but anyway, no other choice, this is not repairable.

Again, what can have caused such corrosion and do you guys think I can question Yamaha about this?

I have reassembled the powerhead, for now I don't know this engine very well and Yam's drawings are not always very clear, this would help if someone has some drawings/pictures to reconnect everything (and a picture of the oil level guide, I think I twisted it during the desassembling)

 

[schematic]

Again, what can have caused such corrosion and do you guys think I can question Yamaha about this?

Doubt Yamaha will help. Apparently they beat a class action law suit on corrosion.

 

[FrenchFry]

Probably... As far as I saw the class action concerned engines from 2000 to 2005, mine is 2008, I have plenty of invoices showing how this engine was maintained, maybe the mechanics did not do the job correctly (the anodes for example in the exhaust cover were all plenty of salt), but can really this explain this level of corrosion?

 

[FrenchFry]

No Title

Little help needed for the wiring/connections, these fxcks forgot again things, I don't know exactly how to connect everything in first picture.

They forgot the water/fuel filter, so I have it now, this is the blue connector.

The square connector in my hand with the red cable is to connect a second battery, OK.

What is the triangle connector?

And what are the white and (apparently not used) other connector with rose cables that I have put near the oil filler for the picture?

See on the second picture the cable that goes to the throttle, I have the white adapter that apparently fits nowhere.