5 year / 200 hr OX66 maintenance ??

[fritter]

Looking for recommendations for 200 hr maintenance on my 150 OX66. This motor has seen low, but consistant hours year round since new. Had factory "tune up" done at 25 and 100 hrs and all maintenance mentioned in the owners manual has been followed. I've actually replaced lower unit oil / fuel water seperator / plugs about every 40-50 hrs. O2 sensor and draw tube was cleaned at about 100 and 150 hrs. Water pump last done at 100 hrs - due again this season. I use Ringfree (or similar) in about every tank. Have "shocked" treated about once a year.

What about replacing thermostats and high / low pressure fuel pumps as preventative maintenance at this point?

fritter

[jb123]

(I) do stats every year along with prv parts and waterpump.
you should also crack open your vapor tank and clean the filter, at least drain it regularly, and change out the cartridge filter on motor if its not light/white.
wouldnt hurt to do the lp pumps also and not too expensive, round $34 each.
i have 00's myself and blew a head last year due to a warning buzzer... $4500 lesson for a 40 dollar part.

how'd your o2 sensor look after ringfree the whole time??

[fritter]

O2 sensor looked about "normal" is what my tech told me. It needed to be cleaned but didn't look too bad. After he told me that I stopped worrying about ONLY using Ring Free and have been using the cheaper SeaFoam/Merc version since.

Where is the vapor tank located? ...are the low pressure pumps easy to replace myself? (I'm fairly mechanically inclined) If not what kind of labor would a shop charge?

[jb123]

vapor tank is the large aluminum tank on port side and the high pressure filter inside should be cleaned yearly. the low pressure pumps are just to the right of the tank and both are relatively easy, just ensure you close the tank correctly or you could have gas squirting under your cowl. run it after the job to check for leaks....also you will need 1 vst tank o-ring , fuel pump gaskets and new rimp hose clamps.

you will most likely find the best prices here.

[PJM]

jb123

I have run an 225hp OX66 for 5 years and have never cleaned the VST filter. I also run a water separating fuel since I owned the motor and changed it every year. The only problem I had was last fall When I stopped for an hour or so the motor would start hard and I would have to give it gas to get it going and it smoke a little bit like it was flooded. Once the motor started it ran fine at all rpms and started fine cold. I have drained the VST tank every year, could this problem be related to bad low pressure fuel pumps, One of the pumps would not hold pressure and the others made a crackling sound like the diaphragms were dried out, what are your thoughts? Also Ring free has been tested by Yamaha and in my opinion is a better product the Sea Foam.

[jb123]

( PJM )

if you have known bad low pressure pump why wouldnt you change it?
draining the tank MAY help rid of some debris but at $800 bucks personally i dont like to chance it bY not cleaning the filter. and as far as ring free and sea foam, both as far as i know both contain techrolene so it just depends on whose label you prefer......ALTHO it seems ringfree is a lil more concentrated as the volumes will treat more gas.

[PJM]

jb 123

I was looking for your opinion as far as the motor being hard starting if the fuel pumps were bad. Being that the pumps are 7 years old I did replace them. The ingredients in Sea-Foam are Pale oil, Naphtha and IPA. Naphtha is a solvent, and is also like white gas used in Coleman stoves. Unless something has changed in the product, it does not have techron in it. Ring-Free was made once by Chevron and Techron was the cleaner in the product.