Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

[Prophammer]

Boat; 1987 Regal Sebring, Engine 4.3 Mercruiser 175 I/O, Drive; Alpha 1, Trim oil; I don't know what I should put in it. Trim pump has a see through plastic resevoir, trim cylinders have a Forward line and an Aft line going to them. Any info would be welcomed,
Thanks,

 

[45Auto]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

From Mercruiser manual #6, 1983-1990 Sterndrives - R,MR,Alpha 1, Alpha 1 SS:

Oildyne pump plastic resorvoir, Oildyne pump aluminum resorvoir, Prestolite pump (in other words all types of pumps:

IMPORTANT:

SAE 10W-30 or 10W-40 engine oil can be used in system, if Quicksilver Power Trim and steering fluid is not available.

 

[Prophammer]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

Thanks for that, I guess now I will flush the dexron out of it.

 

[90stingray]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

No need to flush the atf... if that's what you want to use, its fine. Some actually prefer it so you can distinguish between leaks if you have one. But I just used 5w30... its what is always on hand for me.

 

[Don S]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

No need to flush the atf... if that's what you want to use, its fine.

You don't mix types of oil. If it had ATF use ATF, it's red. If it was the color of engine oil, you don't just start putting in atf and call it good.

 

[90stingray]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

You don't mix types of oil. If it had ATF use ATF, it's red. If it was the color of engine oil, you don't just start putting in atf and call it good.

That's what I meant to say, but I guess I didn't get that point across. I was thinking a fresh system since I just changed my pump assembly out

 

[Prophammer]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

Well, what started all this was; my ATF was pink and aerated looking and the pump was noisy-er than my other trim units. Since yesterday I removed the lines and purged as much pink stuff as I could and continued flushing with 10w30 (it was the only w I had around) untill straight 10w30 came out, topped of & rechecked, no more aerated looking oil but pump still kind of noisy. And trim was sticking at times(forgot to mention that) but it is working now.

 

[HT32BSX115]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

Well, what started all this was; my ATF was pink and aerated.

It's probably not aerated......it's "waterated"! You may have a trim cyl leaking. Or you had a lot of water in the bilge at one time.....

 

[Prophammer]

Re: Mercruiser Trim Oil, should it be Dexron ATF or 10w30 engine oil?

it's "waterated"! Or you had a lot of water in the bilge at one time.....

She (the Regal) was holding a lot of water when I first got her off the lake, she had been adrift in a few storms. She got loose from the dock with no battery to run the bilge pump. But I will keep an eye on the oil for more "wateration". Thanks! I have new words now.