Offshoreonly.com - Wanted Merc Speedmaster V drives

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AEX... I have transoms and IIIA's 1:33 ratio, perfect for your cat, cam off of mine, they were fresh with new gear sets... let me know if you wanna talk about them... I'll cut ya a great deal on them

I'm sending my fives to Offshore in Ft Laud for refresh and since they are getting scarce I figure some extra drives may be worth the investment , but I'm not going to buy for junk .
I cracked IV gear cases over the prop shafts several times , this never happened with the V's .
I'm dialed for the V drives on boxes anyway so going to III's would throw everything off .
Thanks for the offer .

Quote:

Originally Posted by RMPRam (Post 3616430)

I enlarged the pictures and it is extremely difficult to tell, as they are so dark, if the upper housing is one of the latest design, #5 housings. The last design #5 upper housing was "smooth" on the side where the 6 stud holes are. The early #5 and all the #4 upper housings were "scalloped " around these stud boss's. A #5 lower case might have a V stamped in it immediately in front of the wear plate area. The true way to tell is separate the upper and lower housings and look at the front verticle shaft. A #4 and early #5's were polygon in shape. A true #5 will have a splined front verticle shaft. Also the spur gears on a #5 are 1" in thickness. Also look at the OD of the trim pin hole in the rear of the upper case. On a #5 it is 1" in comparison to a 7/8" pin for a #3 or #4 drive.
Hope this helps.
Gary Kollofski
612-247-7081

What I noticed is they have oil fills on the upper gear case rear cover and I don't think this is right . Either way they probably need rebuilds and aren't worth the asking price imo .

I checked today and was told that if there is a fill port in the rear cap, it is probably a real early #4 drive from the early 80's. A true #5 will not have a fill port on/in the rear cap.
Gary

how much HP were you putting thru the IV's that caused the shafts to break? You have me worried now.

Quote:

Originally Posted by MILD THUNDER (Post 3617576)

how much HP were you putting thru the IV's that caused the shafts to break? You have me worried now.

At that time 750 hp totally surfaced on the cat with extn boxes . The lower gear cases developed a crack in the housings vertical trailing edge about 1.5 inch below the cavitation plate after 4-5 races . I switched to fives when they were introduced and then never had another problem with 950 hp in a light 30 footer .

[QUOTE=aex;3617797]At that time 750 hp totally surfaced on the cat with extn boxes . The lower gear cases developed a crack in the housings vertical trailing edge about 1.5 inch below the cavitation plate after 4-5 races . I switched to fives when they were introduced and then never had another problem with 950 hp in a light 30 footer .[/QUOTE

So a V has a stronger case than a IV??

Quote:

Originally Posted by aex (Post 3616100)

I'm looking at these pictures blown up and I'd swear these are IV uppers with V lowers bolted on although looking at the lowers from these photos it's hard to tell what they are exactly .

I know this is a bit old but I'm curious if IV and V uppers and lowers are interchangeable?

They are not interchangeable . A 4 will bolt onto a 5 gimbal though