Reg Maintenance 150 OX66

I'm looking for some advice on what regular maintenance items should be performed on my friends 2000 150hp OX66.<br /><br />It's always been professionally maintained but the engine is out of warranty now and the expense is getting excessive. Also, it doesn't seem like the dealer was going to do anything other than putting in new plugs and a fuel filter. Is there anything else that we should be doing? Is there anythign unique about doing these two items on this engine? Anyone have p/n's for the filter or plugs so I can tell him what to buy them ahead of time.<br /><br />FYI, the lower unit oil was changed and the gas stabilized in the fall. He does not run ring-free regularly.<br /><br />Sorry for all the questions on my first post. I need to help this guy out on Saturday though.

Re: Reg Maintenance 150 OX66

I think the quickest way to get some info would be a search of this site. There really is a lot posted on that model. My dilema is always building the confidence to turn the wrench when attempting a new service or maint. procedure. A guy hates to screw it up, but it is also how we learn and save a few bucks. O2 sensor for sure.

Re: Reg Maintenance 150 OX66

I'd done a quick search looking for a spring commissioning checklist or something like that but didn't come up with anything. He's only got 70 hours on the engine and we have a limited amount of time this weekend so I was planning to pass on the O2 sensor cleaning for the time being. I don't actually have the crows foot socket anyway so I thought that would be something that could be tackled during the season when there's more time.<br /><br />Honestly, I'm a little nervous messing around with such an expensive sensor anyway. At close to $300 a pop, I'm wondering if it doesn't make more sense to leave it until it starts to go and then trying to clean it. At that point, if cleaning doesn't work, you can always replace it. I'm concerned about breaking it accidentaly when trying to remove, clean and reinstall it. <br /><br />I'm pretty ham fisted. I always buy extra spark plugs becuase I end up breaking one.

Re: Reg Maintenance 150 OX66

check the marine tech guide, it has a list of hourly OR repeat OR calander scheduled maint.<br /> at 6 years old with 70 hours ill bet a sixer its a neglected beast,<br /> however your maint plan is sure to enrich some techs bank account and buy him a new pair of shoes.<br /> by the way, your first inclination the O2 sensor failed is when #1 piston pops.<br /> there is a lot of maint on that motor other than gear lube and sparkies.

Re: Reg Maintenance 150 OX66

He's actually the original owner and it's always been dealer serviced so I'm not real worried about it being neglected. The low hours are more a result of good geography than lack of use. There's just no need to go to far from home to catch plenty of fish here.<br /><br />Where can I find the marine tech guide? I'm trying to find out what else I need to do beside the obvious. I'll be able to pick up at least an aftermarket manual tomorrow morning but, I was really hoping to try and find as much information as possible in advance.<br /><br />What keeps the engine from running badly or knocking before throwing a piston out the block when the O2 sensor starts to get dirty? I'm not adverse to cleaning it. It's just that given the cost, I don't want to risk breaking it while trying to clean it if it's not dirty.

Re: Reg Maintenance 150 OX66

whats the symptomws of a dirty/failed sensor. the marine tech guide is avalible at any yamaha dealer,<br /> by now it should have had a few services, like I say 99% of the time you show me a 5 year old low hour motor and ill show you a motor that has not been maintained in accordance with the manufacturer, when ya get a copy of the 2 stroke EFI maint page we can disscuss what was done at the correct intravel and what has been allowed to slide cause"its got no hours".<br /> then we can help you figgure out what ya have to catch up on.<br /> and dealer serviced can mean anything from its actually maintained or some 5 star (Video course that took me 20 min to complete) tech has changed the plugs and lowerunit oil and nothing else.

Re: Reg Maintenance 150 OX66

I would expect the engine to run rough/knock with a failing sensor. That's been my experience in the car anyway. I'm obviously no expert just trying to understand what's going on in there.<br /><br />I suppose the block might be engineered to such tight specs that one misfire could do the damage but considering their reputation I wouldn't expect that. I agree with your suspicions on the quality of the dealer service. That's one of the reasons I'm looking here. That said, my buddy is nervous and skeptical about doing it himself and isn't sold on the idea that this is going to be an ongoing thing for him so, I'm not gonna convince him to spend a couple hundred $ on a shop manual the first time out. Can you reccomend an aftermarket one or do you find them all pretty much the same?

Re: Reg Maintenance 150 OX66

I think my manual was 60 bucks for a yammi version. I'm not knockin my dealer, but if I didn't ask for anything specific, it's plugs and gearlube, which are the easy do it yerselfers fer sure. Like I said, it's gaining the guts to do it yourself. Wish us both luck I guess, I'm going to start on a pressure valve grommet. Try a generic ox66 search if you want, lot's of posts.

Re: Reg Maintenance 150 OX66

You're kidding, sounds like the manual is one thing that's definitely a bargain. I think I paid in the area of $200 for the 3 manuals for my old Merc I/O (Engine, Outdrive & Wiring).<br /><br />I can actually sympathize with the dealer too though. I think at least half their customers would be pissed if he actually did everything and charged for it. A guy that will flip up to a larger boat every few years isn't going to be bothered by shoddy maintenance but the expense of doing it properly sure will. The truth is that's the kind of guy that keeps them in business.

Re: Reg Maintenance 150 OX66

anmd that is the issue, it will work fine with no maint for several years, the poor tech that gets that last one is a mutt in the customers eyes.<br /> the O2 sensor on the OX66 affects and fine tunes the fuel delivery at ALL RPM's, and its identical to the 4 wire sensor used in some automobiles only now we are gonna intentionally place it in a very oily exhaust with double the exhaust heat and the pistons have to be lubricated by the incoming fuel/air/oil mix.<br /> unlean every thang ya ever knowed about grannies grocery getter. it will kill you outboard.<br /> that 200 is a finly tuned high performance machine capeable of extended periods of full load output, if all the subsystems are happy, let the cooling or fuel system degrade and pistons go away rapidly.<br /> just think how many nascar guys run 3 year old gas and last years cooling systems.<br />your outboard is not much different. now were gonna add hot saltwater to the mix and them nascar guys are clueless. salt does not care about engine run hours, as soon as the salts are absorbed in the casting pores it starts its thing.

Re: Reg Maintenance 150 OX66

Well over the weekend we actually started tearing in to the thing and got a Seloc manual (which seems to be a lot better than I'd expected). We ran in to a couple hitches in the form of a corroded battery cable and poorly stocked parts dealer so we didn't have time to get everything done but now that I've actually seen the motor, everythign makes a bit more sense.<br /><br />That O2 sensor looks like it couldn't be any easier to get at so I'm not too worried about breakage getting it in or out and I have the article on how to clean it but any further advice or tips are appreciated. changing the fuel filter under the cowling looks simple enough once the parts come in.<br /><br />There is a second canister filter in his boat that's tucked behind his oil reservoir. The reservoir will need to be pulled to change the filter but that seems pretty easy to do. I didn't have a chance to look too closely but from a quick look at the lines in & out, it looks to be a fuel not an oil filter. Does that make sense. Where does the oil get mixed in? in the lines before heading in to the ingine or under the cowling somewhere? It's been a long time since I ran an o/b with oil injection so I'm wondering if there is a seperate oil filter.

Re: Reg Maintenance 150 OX66

The second cannister is most likely the fuel/water seperator. This should probably be changed as well.<br /><br />I believe the oil gets mixed in with the fuel inside the VST tank under the cowling.<br /><br />-- Tom

Re: Reg Maintenance 150 OX66

That's what I think too. I think the one under the cowling is also water seperating filter with just a replaceable element inside a plastic canister. I think this larger one behind his oil tank is the first line of defense. We'll bring that one in to the parts dept though to see if we can't switch it for a drainable Racor can.