Mercruiser 420 Oils - Zinc Additive?
#1
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Joined: Nov 2012
Posts: 5
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From: Ithaca, NY
Hi,
In the next couple weeks I'll finally be performing the spring maintenance on my new boat I bought in December. Its a 1989 Fountain Lightning 33 swim. Has twin Mercruiser 420's (454 CI) with TRS drives. I cant wait to get it out. The previous owner had a bad lobe on one of the cams, so he had that motor converted to have a roller cam with roller lifters (stock rocker arms).
The other engine still has the flat tappet cam. I was told that I should be using a zinc additive to reduce wear in these older flat tappet engines. Anyone have any experience with this? I have been researching it and found that most oils no longer have zinc in them. I did find a few that do, and am leaning towards Kendall 20W-50 GT1 oil with zinc in it already. I also was told Rotella oil works well. Should I be adding additional zinc? Which one do you guys use? I heard Lucas makes it?
Is the oil capacity 6 quarts?
Also it has BorgWarner Velvet drive transmissions. (I actually work at BorgWarner, lol) Do I use regular ATF? Which brands work well? What about capacity?
I have a good understanding on how to change the drive gear oil. Pretty much identical to an Alpha 1 drive.
That should be it for now. Just gotta change engine oil, transmission oil, drive oil, wash and wax, and I should be good!
I'm sure ill have plenty more posts, since this is my first season with a performance boat.
Anyone boat on Oneida lake near Syracuse NY? I'm new to the area and looking for boating people.
Thanks,
Matt
In the next couple weeks I'll finally be performing the spring maintenance on my new boat I bought in December. Its a 1989 Fountain Lightning 33 swim. Has twin Mercruiser 420's (454 CI) with TRS drives. I cant wait to get it out. The previous owner had a bad lobe on one of the cams, so he had that motor converted to have a roller cam with roller lifters (stock rocker arms).
The other engine still has the flat tappet cam. I was told that I should be using a zinc additive to reduce wear in these older flat tappet engines. Anyone have any experience with this? I have been researching it and found that most oils no longer have zinc in them. I did find a few that do, and am leaning towards Kendall 20W-50 GT1 oil with zinc in it already. I also was told Rotella oil works well. Should I be adding additional zinc? Which one do you guys use? I heard Lucas makes it?
Is the oil capacity 6 quarts?
Also it has BorgWarner Velvet drive transmissions. (I actually work at BorgWarner, lol) Do I use regular ATF? Which brands work well? What about capacity?
I have a good understanding on how to change the drive gear oil. Pretty much identical to an Alpha 1 drive.
That should be it for now. Just gotta change engine oil, transmission oil, drive oil, wash and wax, and I should be good!
I'm sure ill have plenty more posts, since this is my first season with a performance boat.
Anyone boat on Oneida lake near Syracuse NY? I'm new to the area and looking for boating people.
Thanks,
Matt
#2
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Joined: Jul 2004
Posts: 11,332
Likes: 73
From: chicago
TYPE F in the transmissions.
As for the oil, yes you want a oil with a good amount of zddp. Heres a good article explaining things about oil
http://www.enginebuildermag.com/Arti..._slippery.aspx
As for the oil, yes you want a oil with a good amount of zddp. Heres a good article explaining things about oil
http://www.enginebuildermag.com/Arti..._slippery.aspx
#3
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Joined: Mar 2009
Posts: 1,758
Likes: 3
From: OFallon,Mo.
I run the Valvoline VR1 20-50 racing in my flat tappet engine. Has a good amount of zinc in it. As for your drives just FYI they hold 3 quarts in the drive and one in the reservoir built on the transom plate.
B-W trans capacity is 2 quarts.
B-W trans capacity is 2 quarts.
#4
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Joined: Oct 2005
Posts: 756
Likes: 1
From: New Hartford CT



