Pre-mixing along with oil-injection?

[sbva]

Just purchased a rig with an 85' 150 XR4. After I get through the initial cold-start she runs great. <br /><br />Anyways, previous owner recommended me adding 16 ounces of oil to gas whenever I filled it up even though the motor is oil injection. <br /><br />Is this good, precautionary advice or is he being overly cautious? Will the added oil in the mix foul plugs etc or is 16 ounces a minimal amount?<br /><br />New to the boating universe. These forums are great, answered so many questions without me having to ask

 

[JB]

Re: Pre-mixing along with oil-injection?

Howdy, sbva.<br /><br />Welcome to iboats. <br /><br />Using premix plus oil injection is a common practice during break-in, and to help diagnose failure in the oil injection.<br /><br />It is not recommended for normal operation because it increases smoke, carbon buildup and emissions.<br /><br />16oz oil to how much gas?

 

[Scali]

Re: Pre-mixing along with oil-injection?

I dont agree with our fearless leader { who does a wonderfull job with theis site BTW }.<br />I think with that 150 motor it's pretty common to run 40-1 which is what it would most likely add up to with the 16 ounces in his tank assuming it's a 12 gallon.<br />I started premixing with my oil inj. last season because the tubes were overdue to be changed. I changed the tubes this year & have continued this practice , motor runs great & it's worth the piece of mind of having premix in the gas that should save the engine if the oil pump fails. <br />I add a couple ounces of seafoam per tankfull as well & will do 2 decarbs this year approx. 1 every 75 hours...<br />I bet theres people who may think it'll produce too much carbon & it's not good but I dont..<br />Theres no extra smoke that I notice, thats not a problem.

 

[dajohnson53]

Re: Pre-mixing along with oil-injection?

Although I don't think a little extra oil will hurt anything, to me this doesn't make any sense at all. Either you trust your oil injection or you don't. If you do trust it, why would you add extra oil? If you don't, and are going to premix anyway, just disconnect it and premix at 50:1 and be done with it. Just mho, of course.

 

[Scali]

Re: Pre-mixing along with oil-injection?

Peace of Mind.<br />I noticed the engine seemed to run a little better with extra oil & the added benifit would be saving the engine if the oiler fails.<br />If I sell the engine it'll come with a working oil injection & the new owner will opt to do keep it or premix.<br />I never got around to pulling the plastic gear for inspection when I do & if she looks OK I may not pre mix too but not sure..

 

[LubeDude]

Re: Pre-mixing along with oil-injection?

Interesting descusion. Fact of the matter is that 2 cycles will produce a bit more power from using a bit more oil. As far as actually protecting better, thats a toss up, I happen to think that the posibility of more carbon build up isnt worth it.<br /><br />Now if you are decarbing twice a year I guess it isnt a factor, but if you are going to all this expence, then why not use a good synthetic at the correct ratio and have the best of both worlds?

 

[Scali]

Re: Pre-mixing along with oil-injection?

I thought of it, I believe the Merc oil I'm using may be part synthetic but not sure { the name escapes me but it's thier top shelf stuff for EFI motors }.<br />Another benifit of running extra oil is in my area the E 10 gas { ethanol 10 % mix } <br />is now law & this stuff is pretty caustic, I figure the extra oil may be helpfull with this fuel.

 

[JB]

Re: Pre-mixing along with oil-injection?

There's always someone who knows more than the guys who designed an engine.<br /><br />I am not one of those guys and am inclined to do things exactly as the manufacturer says to do them.<br /><br />Caustic? Ethanol? nonsense.

 

[Scali]

Re: Pre-mixing along with oil-injection?

My Mitsubishi pickup's owner manual recommend's oil changes every 7500 miles.<br />I guess I should follow the manufacturers guideline there too ?<br /> " Caustic ? Ethanol ? nonsense " quotes JB..<br />Honestly, thats just funny..<br />This stuff is creating huge issues with phase seperation & gunking up carbs in my area, E 10 gas isnt to be used in airplanes & this stuff destroyed fuel systems in the past before the carmakers upgraded the quality of the gas lines , fuel pumps, carbs ect..in the late 1980's..<br />Yup ethanol is a powerfull additive, you can take that to the bank, & if they start mixing it above 10 %, these outboards wont run on this stuff .

 

[JB]

Re: Pre-mixing along with oil-injection?

Look up "caustic".

 

[Scali]

Re: Pre-mixing along with oil-injection?

Caustic; corrosive, capable of destroying or eating away by chemical action..<br />?????

 

[JB]

Re: Pre-mixing along with oil-injection?

Rubber and some plastics are softened by alcohols, but destroyed or eaten away?<br /><br />Well, it's just semantic nit picking, anyway. Never mind.

 

[verojoe27]

Re: Pre-mixing along with oil-injection?

I was having oil alarm problems with my 1992 Merc 150. It turned out to be bad outside switchbox that which has a lead that connects to the oil warning module. Well, I mixed my tank 50:1 premix until the problem was diagnosed. The oil injection is working fine and my engine runs as fine as it ever has. Smoke on startup is more than before but besides that no problems. I would recommend checking the plugs for fouling every few times out just to be safe. Good luck, Joe.

 

[geezus]

Re: Pre-mixing along with oil-injection?

Originally posted by D.:<br /> Although I don't think a little extra oil will hurt anything, to me this doesn't make any sense at all. Either you trust your oil injection or you don't. If you do trust it, why would you add extra oil? If you don't, and are going to premix anyway, just disconnect it and premix at 50:1 and be done with it. Just mho, of course.

I was thinking about doing this with my 90 hp. Mercury. (un hooking the oil injection).. What is the process ? And what happens to the oil pump when you do this ? Does it have parts inside that will dry out ? Or do I just un hook the elctronic alarm,and start pre-mixing.. HELP. I need to hit the lake ASAP........ thx.

 

[gss036]

Re: Pre-mixing along with oil-injection?

There are lot of people who hang out here, like me have older boats and engines. When I first bought my boat in Feb 1989, I would use gas at the AM/PM (ARCO) station by my house. They were using alcohol then. This went on for just over a year until I took the time to read the Mercury manual, which said not to use gas w/alcohol in my 200hp engine. I stopped using it, but I was starting to get a gas odor in the hull of my SeaCraft23WA, w/115 gal tank. I finally found the source, a softened fuel line which was seeping gas by the tank outlet. I really strongly feel that was caused by the alcohol in the gas. I might also add, my engine threw a rod through the block at 13 months and 140 hours. Power Head time and Mercury said sorry, you are outside of the 12 month warranty, thank goodness the sales manager ahd encouraged me to buy an extended warranty, so I only had to pay the sales tax. Whether this was caused by the gas/alcohol,I do not know. I am still running the same engine, but no alcohol since. I sound like I am rambling so will stop here. Thank you for your patience.

 

[crookedmullet]

Re: Pre-mixing along with oil-injection?

I've heard my friends say many times that there oil pump is working fine until they were coming back from an offshore trip and the grinding started. At that point, rebuild the block or purchase a new engine are the only two options. Unfortunately, it happened to me and, let me tell you, it's not fun. <br />I decided to have it rebuilt cause it's the cheaper way to go about it.<br />Bill, if your engine is like mine, you would have the oil reservour under the cowling. <br />-Remove the screws holding the oil tank. Make sure you tighten the support bracket screws to 180 in.-lb, and tighten the starter motor bracket bolts to 175 in.-lb. Disconnect the low-oil sensor wires located at the bottom of the tank, they should be bullet connectors.<br />-Disconnect the pump inlet and outlet lines from the oil pump. Be careful, with oil in the reservoir, plug the lines or you'll have oil going everywhere.<br />-Disconnect the line going from the oil pump to the fuel pump and replace male adapter from fuel pump to one a solid fitting that will block off the hole(your local hardware store should have some thing like that).<br />-Add oil, I use 50:1 ratio to the fuel tank. Make sure that you empty out the fuel line so you have the oil/gas mix going into the carbs.<br /><br />If you don't feel comfortable doing this, my buddy had his done at a local shop for $65, and it took less than 2 hours to do it. So the choice is yours. Good luck!

 

[Scali]

Re: Pre-mixing along with oil-injection?

Unfortunatly here on long Island the only gas you can buy nowadays is 10 % alcohol, sucks.<br />Seems lots of Yamaha outboards with EFI or HDPI are not running well with it.<br />My 10 year old carbed Merc has been doing OK on the fuel I credit part to a cleaned out fuel tank to start hence no phase seperation or gum up { easy to do with 12 gallon above deck tanks }.<br />You have to really keep the fuel tanks clean & moisture free with this gasahol crap..<br /><br />As far as that Merc plastic oil pump gear goes, it's a shame they never updated them to a brass piece or @ least include inspection & or replacement of the gear itself every couple years in the maintence requirements .<br />It's a neat little oil injection system that has that annoying & potentially engine blowing weak link, the dreded plastic gear..

 

[Robot19]

Re: Pre-mixing along with oil-injection?

Owners of 1989 and newer engines can forget about oil problems. Install an Electronic Oil Injection system from Go2Marine.com. Check out the recommendation in the Oct 2004 issue of Bass & Walleye. EOI runs the pump with an electric motor and a small computer. No more oil problems!