'99 OX66 complete fuel system "flush out"

[sstarnes]

I have just recently purchased a boat with a pair of '99 Yamaha 225 OX66 engines which have been sitting for over a year. I was assured that these were properly winterized and stored only to find out that the pumps are "stuck" and the VST tanks are full of "surupy" gasoline. I have had both fuel tanks cleaned and all old fuel removed and will probably work my way back towards the engines in cleaning out the fuel systems. I am very new to outboards and at this point need information and procedures especially with respect to the "stuck" VST fuel pump. All help/comments are greatly appreciated.

 

[John from Madison CT]

Re: '99 OX66 complete fuel system "flush out"

Glad you made it over to this forum. Between Ray and Rodbolt, you will be well taken care of.<br /><br />First, you have to get the Service manual. Go to:<br /><br />www.yamaha-motor.com and find your way to the publications area.<br /><br />Removing the VST tank is not hard. In fact I just did it for the first time. There are some hoses and a couple of wires, but all in all, not hard. The 3 bolts holding it to the block are the hardest to get to, but accessible nonetheless.<br /><br />If in fact the VST Pump is ruined, you will need new ones, which are expensive. Retail is $750, but I know of places that sell them for under $600.<br /><br />Email me if you have more questions at: jmetaxas@aol.com<br /><br /><br />John

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks John,<br />Great to be on the forum. Ordered the Yamaha service manual last week. Once I get the manual, I will be able to locate all of the filters, and corresponding O-rings to replace. I will try to free up the stuck VST pumps first. These engines have less than 160 hours on them since new. It would be great to get them running reliably.

 

[rodbolt]

Re: '99 OX66 complete fuel system "flush out"

hello<br /> do you have external fuel water seperators?<br /> if not install a pair with 10 micron spin on filters.<br /> replace the engine mounted filter. replace the low pressure fuel pumps.<br /> old gas tends to eat at the plastic and rubber pump parts. now fow the VST.<br /> all it is is a gas tank that the high pressure pump can draw from.<br /> you dont have to actually remove the hoses just remove the tank from the block. loosen all the phillips headed scews you can before revoving the 3 6mm bolts. you will need to remove the nuts that hold the red and blue wires to the pump. make sure you order the pump oring sometimes it does not come with a new pump. the old one if not torn can be reused in a pinch you may also need a new oring seal on the tank. use vasoline in the tank groove to hold it in place.<br /> <br /> now for the stuck pumps<br /> buy 2 or 3 cans of combustion chamber cleaner. seafoam may work as well and is cheaper.<br /> fill a long cylindrical container with it. remove the pump filters and drop the pumps in,<br /> soak them over night<br /> after a good soaking take 2 jumper wires and hook the neg pump terminal to the negative battery term. hook the positive battery terminal and use the other lead to touch the positive pump terminal. you may have to lightly tap on the pump body. sometimes you can reverse the polarity on the terminals momentarily to break the armeture loose.<br /> try that and see if they wont break loose<br /> I have heard of people dissasembling the pump.<br /> this is not reccomended as gas flows past the brushes and armeture and improper reassembly could lead to a fire.<br /> good luck and post us back

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks rodbolt,<br /><br />So I should replace all of the low pressure pumps? Shows (3) per engine?

 

[Ray Neudecker]

Re: '99 OX66 complete fuel system "flush out"

Yes, replace the old pumps. I have used 24 volts to unstick the high pressure pump if all else fails.

 

[rodbolt]

Re: '99 OX66 complete fuel system "flush out"

yep what Ray says.<br /> the 24 volt trick is a last resort and dont try to run it on 24v just unstick it and go back to 12v. if it burns out the wiring it was junk anyway.<br /> glad to see I am not the only one to try that

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks Guys,<br />With the boats fuel tanks polished, and inspected I guess I will just work my way back towards the engines cleaning and/or replacing as I go.

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Forgot to ask:Should I remove and soak the Injectors?<br /><br />Thanks

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Bump

 

[rodbolt]

Re: '99 OX66 complete fuel system "flush out"

not usually nessasry just make sure all are injecting. run the shock treatment of rinfree once its running.<br /> to inspect the injectors spray pattern you can remove the plugs, attach a spark tester to all plug leads and crank he engine while watching down the throttle bores. of you can manually trigger each injector by jumping the ground side of the injector to a momentary ground and watching the spray. you will have to repressurize the fuel rail after each toggle. be aware that your working with fuel under pressure. it burns rather rapidly. keep fuel spill cleaned up and always have the old fire bottle handy.

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks,<br /><br />Just got the boat delivered today. COLD AS HELL and RAINY....!!! Will try and sort this out. One os the engines wont trim down.. Thanks for the help !!

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks for all of the help.<br /><br />I was able to unstick the VST pumps and clean out the seperator tanks. Awaiting additional parts to complete. Something very alarming I discovered on the stbd engine: The 'Bypass valve and housing are VERY corroded and the housung itself if broken. The little black plastic plug is surrounded by corrosion is stuck inside. Help!<br />See pic @:<br /> http://thehulltruth.com/photos/show-album.asp?albumid=973&photoid=7270

 

[rodbolt]

Re: '99 OX66 complete fuel system "flush out"

sounds like you have a pair of highly maintained saltwater motors.remove the housing. remove the plug with nedle nose and remove the rubber grommet. the plug is the actual valve. replace the housing. useing a pick carefully clean the pocket that the grommet sits in and carefully install a new grommet. dont drop it in the water cover. its a pain to dig back out. goes back to a complete cooling system maint.

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks rodbolt,<br /><br />Yes, the boat was such a good deal the motors were just about freebies. I plan to repower eventually, but would really like to get these '99 225's up and running.<br /><br />Moving forward, What would you reccomend as to make sure all of the corrosion can be flushed out?

 

[rodbolt]

Re: '99 OX66 complete fuel system "flush out"

leave it be<br /> if you start trying to descale it now you may have more problems.<br />that motor also has cooling system pencil zincs. if you mess with them and they break off you will have to remove the cyl heads to get them out.

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

Thanks Rodbolt, <br />You've been very helpful and I really appreciate yours and other boardmembers assistance.<br />Today has turned out no so well though, I was in the process of removing the gromett fron the bypass valve when it fell into the other side.<br />I was not able to fish it out, and decided to remove the plate. I got some PB blaster and soaked all of the bolts and tapped on them to help with the process. Then I started removing the bolts. All was well when the #22 bolt sheared off flush. I drilled out the bolt and when I went to turn the easy out it broke off also. What would you do in a case like this?<br />Yikes !!!

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

 

[rodbolt]

Re: '99 OX66 complete fuel system "flush out"

well if ya had asked before ya busted them I would have told ya how to fish it. yes I have dropped one or two. <br /> the next thing I wouled have told you was take the easy out and walk to the bow and see just how far you can throw it, causes less problems that way.<br /> so now we not only have a bolt that is stuck with corroision we have a 6mm bolt that has been expanded to create an interference fit and a oiece of hardend steel in it. so now we are down to 3 options, 1 is to try to use a steel pick and work the easy out loose then redrill the hole for the 6mm tap size, not a very good option but with a small try. just dont crack the housing. 2 is if you have the skill and acess to a small tip oxy/acetylene rig you can very quickly heat it hit the o2 and get off of it or the best option is to find a GOOD welder to weld a nut to the broken parts and attempt to remove the stud and all. if your in the norfolk VA area I can give ya a phone number to the welder I use that has done hundreds of the broken easy out cases. its 85 dollars a stud for extraction. more if you want it rethreaded.

 

[sstarnes]

Re: '99 OX66 complete fuel system "flush out"

I am in Austin Texas - yes the easy out just snapped off - I drilled the hole perfect. Really pissed me off!<br /><br />Guess I'll try the tig weld method???<br /><br />dont want to mess up the stud surface so the gasket will seal.<br />I have this sinking feeling like you would not believe.........