5w-20 motor oil in the trim pump????

[aroncornell]

Ok so after I finally got my trim pump working correctly I had noticed it was low on fluid and told my buddy that was with me about it. As I went in the house to refresh our beers, he informed me that he had filled it up with 5w-20 motor oil and works great. I cringed when he told me because I had read the sticker stating to use 20w motor oil and I couldn't read the rest. I haven't touched it since so my question is what do I do? Is it ok to leave in and use or do I need to drain the pump and refill with 20 weight motor oil?

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

depends whether or not it was detergent or non-detergent.

 

[aroncornell]

Re: 5w-20 motor oil in the trim pump????

no clue what that means?

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

detergent motor oil + high pressure hydraulics = rubber turning into sludge

 

[tazrig]

Re: 5w-20 motor oil in the trim pump????

Ok so after I finally got my trim pump working correctly I had noticed it was low on fluid and told my buddy that was with me about it. As I went in the house to refresh our beers, he informed me that he had filled it up with 5w-20 motor oil and works great. I cringed when he told me because I had read the sticker stating to use 20w motor oil and I couldn't read the rest. I haven't touched it since so my question is what do I do? Is it ok to leave in and use or do I need to drain the pump and refill with 20 weight motor oil?

I would definitely use a turkey baster like device and suck out the 5-w-20 oil and replace with what Mercruiser currently recommends which is power trim and steering fluid (same stuff for power trim and power steering fluid) Mercruiser part number: 92-858074K01
You might want to empty out the old fluid, put in the new and run the drives up and down a bunch of times to mix the remaining old fluid with the new and then suck it out again and replace with more new fluid.

1) you don't want the wrong fluid in there to begin with

2) you really don't want, as stated above, detergent in the lines if that was what was put in. Those hydraulic lines are real expensive if you have to replace them down the line.

 

[trendsetter240]

Re: 5w-20 motor oil in the trim pump????

x2 get the oil out and replace with the proper oil. It's a heck of a lot cheaper than the alternative if there is a failure.

 

[ziggy]

Re: 5w-20 motor oil in the trim pump????

who's (mercruiser, omc, volvo) and what era trim pump are ya working with?
my '75 mercrusier trim pump states (from mercruiser service manual #2) the correct fluid to use is 20w motor oil. ya can't get 20w motor oil best i know. so if ya can't get what is correct what's a fella to do? myself. my system was filled with motor oil, not hydrolic fluid. so i used 10w-30 motor oil to top mine off (when i had a leak, which i don't have anymore due to repair). so far, i've not had problems with this. i'm going on my 7th year of running my present rig.
so if ya can't get 20w motor oil. what is the recommended fluid to use? i've never seen a service bulletin that states what i should use. from what i understand. mercrusier trim pumps will operate with near anything from hydrolic fluid to motor oil. ya just don't mix the two.
i don't know about the detergent motor oil either. i just know what i've got away with so far and after 6 years of service w/o ramifications. the oil in my rig has never been totally replaced though the resiviour has been emptied and refilled. but the lines and rams were not emptied and still had whatever (i assume 20w oil) it came with when i bought the boat used in 2006 or so. i'm assuming i'm running a mix of old 20w + the new 10w-30 i added. i'm guessing half and half. but still both motor oils.
good luck in whatever ya decide to do.

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

The viscosity of motor oil is secondary to whether or not it contains detergents. The detergent will turn you trim orings into goo. I don't think non-detergent oil is available in anything other than 30w. Use either dextron3, hydraulic jack oil, or aw32 hydraulic oil. If you live somewhere like central africa with 110 degree is your annual low then consider an ISO48 or 64 fluid.

But debating the viscosity of motor oil without worrying whether it is detergent or not? That is like debating which car is best when driving drunk.

 

[tazrig]

Re: 5w-20 motor oil in the trim pump????

Mercruiser keeps changing things around. For instance, for a while they were saying all their motors should run on their full synthetic. Now they are discontinuing the full synthetic and are saying run all motors on their synthetic blend and still change motor oil every 100 hours. If you don't want to spend on the synthetic blend or you are using your engine at or less than 50 hours a year (so you would change your oil every 50 hours anyway) you can use their regular Mercruiser non synthetic 25W-40 and get the same protection. Used to be that the power steering fluid and trim pump fluid each had their own type. Now Mercruiser has combined them and said all trim and and power steering pumps should use their power trim and steering fluid Mercruiser part number: 92-858074K01 even in their older pumps. My power packages are all new this year but my trim pumps are from 1991 (23 years old) and I was still told to use the new stuff in them. It's kind of confusing to follow but I was told the above by both my Merc mechanic and an engineer at Mercury Marine in Michigan within the last month. I tend to go with their recommendations so when something breaks I don't get blamed for not doing something that could have prevented it.

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

20, 30, or 40 years ago you could buy 110 octane gas, your aluminum carberators could sit for years and still fire right up, your 2stroke weed-whacker lasted decades, and non-detergent motor oil was available in almost any viscosity.

 

[adamjr]

Re: 5w-20 motor oil in the trim pump????

your 2stroke weed-whacker lasted decades

Yeah, I got about 4 seasons out of a 2 stroke string trimmer and I make sure I burn the gas out at the end of every season.

 

[HT32BSX115]

Re: 5w-20 motor oil in the trim pump????

I would definitely use a turkey baster like device and suck out the 5-w-20 oil and replace with what Mercruiser currently recommends which is power trim and steering fluid (same stuff for power trim and power steering fluid) Mercruiser part number: 92-858074K01

Mercury has recommended for years that 10W-30 was acceptable for use in the power trim system (which is not really a very "high-pressure" hydraulic system)

I would leave the 5W-20 in there and not worry about it. Just about ANY oil can be used in them and has been.

I use ATF in mine because it's red and I can more easily find the leak. (except it has never leaked)

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

not all mercury systems are low pressure. He never said what engine, year, system he had. if he has a high pressure system and uses detergent motor oil then he can expect 1/2 the lifespan.

 

[dubs283]

Re: 5w-20 motor oil in the trim pump????

I don't think non-detergent oil is available in anything other than 30w. Use either dextron3

dexron 3 does contain detergents

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

dexron 3 does contain detergents

yes, dx3 will impregnate o-rings above certain pressure and cause them to split or crumble. i see this a lot on force 120-150HP made by mercury where they replaced the chrysler specified oil with DX3.

I do not know exact number, but I think it is somewhere around 1600-1800 psi. I say this because Evinrude Johnson used DX3 on their prestolite systems during the 1980's. Most, but not all, of the J/E system had unregulated output. The ones with regulators are set between 1000-1200PSI. Consequently, I assume that the maximum backpressure from prop spinning is 1200 or less. I have never seen any of the J/E systems show the effects of DX3 impregnating the rubber - even when 40 years old.

The effect of Dextron 3 when it exceeds maximum pressure is to make the oring brittle. The effect of motor oil detergents under pressure is to dissolve the rubber and turn it into gooey sludge.

 

[airshot]

Re: 5w-20 motor oil in the trim pump????

This has been interesting reading because on my mercruiser trim pump it calls for 20W-50 motor oil. Doesn't anyone elses call for that?

Airshot

 

[aroncornell]

Re: 5w-20 motor oil in the trim pump????

wow, alot of info here and i kinda still dont know what i should do, lol. its a 73 mercruiser 302 with the mercruiser outdrive, and the trim pump is a mercury pump that states to use the 20w motor oil.

 

[HT32BSX115]

Re: 5w-20 motor oil in the trim pump????

wow, alot of info here and i kinda still dont know what i should do, lol. its a 73 mercruiser 302 with the mercruiser outdrive, and the trim pump is a mercury pump that states to use the 20w motor oil.

Just follow your owners manual.

 

[RRitt]

Re: 5w-20 motor oil in the trim pump????

a lot of 1970's systems called for lightweight motor oil. what changed is that you can no longer buy lightweight non-detergent motor oil. If your manual says 10W motor oil then use ISO32 or AW32 hydraulic oil. If the manual says 20W then hunt down some iso64. If the manual says 30W then you are in luck because you can still buy 30W non-detergent. If the part of the manual that discusses pressure testing your trim pump says to look for a pressure over 1800PSI then avoid dextron3. No matter what the manual says avoid detergent motor oil if you want your trim to last without leaking or bleeding down.

 

[tazrig]

Re: 5w-20 motor oil in the trim pump????

This is right off of Mercury's website:

MerCruiser Maintenance FAQs | Storage & Maintenance MerCruiser FAQs | Mercury Marine


What type of fluid should I use in my power trim system?
Mercury/Quicksilver Power Trim and Steering Fluid – part # 92-858074K01


They may have recommended many different types of oils and fluids in the past but this what they are recommending now for ALL their power trim systems regardless of age.