Can I swap factory tilt/trim from Mercury version 85hp to US Marine version 85?

62Scout

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I have two Force 85 motors. One is a US Marine version without factory tilt & trim, that has had a CMC PT-130 added, which has been a thorn in my side for the past 3 weeks - leaking down internally, takes forever to lift motor then drops it back down in seconds, and still doing it after replacing every o-ring in the thing and seal in the thing. This is a good running motor that was on a junk hull.

The other motor is a Mercury version, with factory dual cylinder tilt/trim, that came on the replacement hull. It was run without oil in the lower unit, which caused the LU to seize up, but the engine was still good. Figured out the hard way that I couldn't simply swap the LU from the other motor over to it.

So I swapped the whole USM motor over to the replacement hull, with the CMC unit, then found the issues with the CMC afterwards.

I was looking at the two today, and it looks like I should be able to just swap over the factory T&T assembly from the Mercury version to the older USM version? It looks like all the pivot points are in the same place for the tilt cylinders, the extra pad that the trim cylinder pushes against is there, bolt bosses are there, etc.

Is this as simple as it looks, or is this going to turn in to another nightmare for me?
 

Nordin

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I have not worked with many engines with T&T but as you says it can be able to swap them.
I think the hard thing is to loose the bolts and nuts holding the T&T to the swivel bracket.
If it is a salt water engine it can be a real PIA.
 

jimmbo

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"and it looks like I should be able to just swap over the factory T&T assembly from the Mercury version to the older USM version"

Close is only 'good enough' with Horseshoes, Grenades, and Nuclear Weapons...
Without having the Model Numbers, to look at the Parts Listings for Both, I can't say Yay or Nay.
 

jerryjerry05

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You have 2 Force motors. Both 85
Neither 85 had anything to do with Mercury, Mercury came in later after the 85 turned to a 90.
The color has a lot to do with the difference between the T@T.
Blue Force 85 was made from 87 to 89
White 85 was from 1983 to 86
The 85 T2T could fit both white and blue with a few modifications.
The 87+ used relays to activate the motor It's a 2 wire motor.
The 86- used a Heavy 3 wire mounted on the dash and HD switch.

When asking particulars about certain motors?? Pictures always win!!!
 

The Force power

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IF you have the indeed have what say; then yes you can.
I have done this a few times & is not too much work.
You'll either have to have both motors laying on the ground or hanging off a host by crank eye-bolt
Remove the bottom clamp(two bolds) & you'll see the pivot-shaft.
I use an old visegrip and clamp it on the bottom of the shaft (not around because you can't just jet) but through
(this is the hard part) -start hammering on the visegrip and the pivot shaft will eventually move down luckily it does NOT have to come out all the way!
(just past the upper-clamp )
Once its far enough out she's loose & installing is easy; lube the top-part of the shaft & hammer it up onto the top clamp.
NOTE; disable the manual locking-mechanism on the motor that you installed the power-trim
 

62Scout

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Ok, so why I'm referring to them as the Mercury "version" and US Marine "version" is I was told prior that the reason one of them has a two piece driveshaft and different lower unit set up is that it was due to changes made after Mercury started making the Force motors. The Mercury version, at least on mine, appear to have the same bolt pattern where the LU meets the..upper? unit. I inititally assumed I'd be able to just swap lower units over, but then found the water tube that goes from the water pump assembly up to the power head is different, making it so I couldn't get the LU all the way up.

It also has a difference where the water intake is (behind the prop, as opposed to higher up on the other motor), and the water pump/impeller is very different. I have no idea if these are running changes during the US Marine tenure or Mercury made changes, or if Mercury has ever actually had any involvement at all..I'm just going off of what I've seen here, and have been told in prior posts.

I also have no idea what color(s) the motor I'm calling the US Marine version was originally, as when I bought that boat, a PO had already stripped and repainted the engine cover...poorly, and never reapplied any decals. I now have the cover from the Mercury version motor on it.

I've never been able to find data tags on either motor. All the websites I've seen say that it should be on the transom bracket, and I don't know if Force just used lousy labels that fell off, or if POs took them off when they repainted them....

As for pictures...this is the backside of what I believe is the factory T&T on the Mercury version motor. This has a pair of square relays bolted to the front of the motor under the cover, and was connected to a 2 way toggle switch on the dash using 16 gauge wire.
20231105_121839.jpg

The rest of these are the US Marine version motor.
This is a wider side shot of the motor, with the "Mercury version" engine cover installed.
20231105_122034.jpg

This is what I was referring to as the upper pivot holes that looks identical to the other motor to me. The threaded rod down at the bottom was added by me as a quick and dirty way to keep the outboard locked down due to the faulty CMC cylinder. The large bolt hole to the right and below the trim adjustment holes also seems to match perfect to where the lower hydraulic cylinder bracket is bolted through on the Mercury motor.
20231105_122014.jpg


This looks like I should be able to simply unbolt the upper pivot pin,and lower bracket off the "Mercury" motor, and bolt it up to the "US Marine" motor, then unbolt and remove the two "arms" that lock the outboard in the raised position and the spring loaded thingy that locks in the lower position.

It just seems like every time I try to do anything that "looks" simple enough, it ends up being a nightmare, and I end up pondering just burning the dang thing down because the universe clearly does not want me to have a boat, lol
 

The Force power

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The "upper pivot bolt" as you refer to, that the the two clamps together rarely come out/apart
In the top picture is still a US marine with (maybe) a Merc trim motor & apparently with typical Merc. clamp-down bolts.
As for the motor on the boat.....looks to me like the old Chrysler cowl
Jerry jerry & others have seen more motors than I & will let you know
To make it easy to switch;
After you drop the LU from both motors; follow what I posted in post #5
 

62Scout

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For all I know, both of these things are a cluster of mismatched parts by this point....both of motors have cowls on them that also have US Marine emblems on the head side of the cowl.

This was the prior owners paint job on the US Marine motor that made me switch cowls...clearly not factory paint, lol. But also means I couldn't use any decals to date the motor.
20231105_134249.jpg

This is the lower unit parts that I was told previous are the Mercury changes, primarily the two piece driveshaft, different water pump assembly, and the toothed bearing retainer rings behind the prop.
20231105_122121.jpg

20231105_134122.jpg

20231105_134140.jpg
 

62Scout

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The lower-unit a Merc "update" version

And that's where my "Mercury version" came from. All I know for sure was that I couldn't shove my earlier LU up on the motor that this one came off of which would have made my life much easier.
 

The Force power

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And that's where my "Mercury version" came from. All I know for sure was that I couldn't shove my earlier LU up on the motor that this one came off of which would have made my life much easier.
I'm not sure if I'm getting this right?
Does the "earlier LU" have a two piece OR one piece drive-shaft?
The one piece came in two lengths 20" & 25" IF the length is correct; it should fit???
Hopefully jerry jerry and/or Nordin will tune in and verify the year(s)
 

62Scout

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I'm not sure if I'm getting this right?
Does the "earlier LU" have a two piece OR one piece drive-shaft?
The one piece came in two lengths 20" & 25" IF the length is correct; it should fit???
Hopefully jerry jerry and/or Nordin will tune in and verify the year(s)

I've confused myself plenty with this as well, lol.

Earlier motor, what I've been referring to as the US Marine version - 1 piece driveshaft, and a water pump that matches what I find being sold everywhere as a Force 85 pump kit/impeller. Plastic bushing fits into hole in water pump, slide overs metal pipe in outboard middle section.

Later motor, what I've been referring to as a Mercury version - 2 piece driveshaft. Very different water pump assembly. Plate that pump assembly bolts to in the LU also different, so I can't just swap earlier water pump assembly to this LU. Plastic bushing seems retained in outboard middle section somehow. Freely spins, but does not come out. Diameter of this bushing is larger than hole in earlier water pump, which leads to why I couldn't fit early LU on later motor
 

The Force power

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I've confused myself plenty with this as well, lol.

Earlier motor, what I've been referring to as the US Marine version - 1 piece driveshaft, and a water pump that matches what I find being sold everywhere as a Force 85 pump kit/impeller. Plastic bushing fits into hole in water pump, slide overs metal pipe in outboard middle section.

Later motor, what I've been referring to as a Mercury version - 2 piece driveshaft. Very different water pump assembly. Plate that pump assembly bolts to in the LU also different, so I can't just swap earlier water pump assembly to this LU. Plastic bushing seems retained in outboard middle section somehow. Freely spins, but does not come out. Diameter of this bushing is larger than hole in earlier water pump, which leads to why I couldn't fit early LU on later motor
The are both Force/US-marine lower-units (there is A later Merc. version(s) that are not compatible)the two you have still are.
The white plastic-adapter on the copper P/U-tube will come off & you can slide on the preferred one
However the water-pump housing & plate can not be swapped-out
 
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62Scout

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I tried for an hour to get that plastic tube piece off the later motor. As I said, it freely spins on the tube, but did not budge vertically. It was as if there was a flange on top holding it in place.

Eventually I just got afraid that I was going to break something much harder/more expensive to fix, and decided to just swap motors altogether, although I hadn't realized at the time that the CMC unit was going to have issues as well.
 

The Force power

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I tried for an hour to get that plastic tube piece off the later motor. As I said, it freely spins on the tube, but did not budge vertically. It was as if there was a flange on top holding it in place.

Eventually I just got afraid that I was going to break something much harder/more expensive to fix, and decided to just swap motors altogether, although I hadn't realized at the time that the CMC unit was going to have issues as well.
Force went to a 2-piece shaft (on the 85HP & some other) in '88 so they could use the same as the one used on the L-drive units
The later version you have came in '91/'9 B model & many other version followed.
Believe me when I say; it comes off, I do it every time when I have a motor just sitting on its mid-section (to protect it)

Forgot to mention; the gear-ratio did change through the years
 
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62Scout

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So I just went back out to look at it again...it's more obvious with the motor laying on it's side what's going on - looks like the plastic is stuck to the tube, and the tube is spinning in the bore/whatever it's connected to up top.

Which now just reinforces my thought - trying to force that plastic off is likely just to damage harder/more expensive things to fix. Given it's on a now spare parts motor, I'm even less inclined to attack it.
 

Nordin

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From my experience the 2 piece drive shaft was on some of the 85Hp from 1989 and the 90Hp from 1990 and up.
Pre 1989 the 85Hp had the 1 piece drive shaft and the water impeller and impeller housing is different between the 1 piece drive shaft and the 2 piece.
Both gear case will fit a 85, 90, 120 and 125 Hp, but remember there are three different gear ratio for those gear case.
Single port exhaust 1 piece drive shaft gear case, 2:1 ratio used on the 85Hp.
Single port exhaust 1 piece drive shaft gear case, 1,73:1 used on the 125Hp.
Single port exhaust 2 piece drive shaft gear case, 1,93:1 ratio.
Dual port exhaust 2 piece drive shaft gear case, 1,93:1 ratio.
This is from my OEM service manual 1988 thru 1991 A models which covers the 85, 80, 120 and 125Hp.
All these gear case will fit a 85Hp.
The gear case in your pics is a dual port exhaust 2 piece drive shaft.
All single port exhaust gear cases had the water intake at the "lump" for the gears, the dual port exhaust had the water intake above the "lump".
BTW my youngest son had a 2 piece drive shaft gear case on his 1988 85Hp Force.
 

jerryjerry05

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in 89 they changed water pump styles.
Not positive but they might swap(not parts,whole pumps)
They introduced the Hell Drive and needed a stub shaft to connect to the L drive.
I believe in 90 when they started on the 90/120/150 they standardized the gear ratio. They all had the same ratio at one point. Markings on the case should tell what's in there.
 

The Force power

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So I just went back out to look at it again...it's more obvious with the motor laying on it's side what's going on - looks like the plastic is stuck to the tube, and the tube is spinning in the bore/whatever it's connected to up top.
The white plastic adapter is just pressed on the copper-tube (unless someone glued it)
DON'T pull the copper P/U-tube out!!
Hold the P/U-tube in place & try then by making a twisting motion while pulling on the adapter.
IF all fails.........you could break the adapter off the tube so you can install the other adapter.
IF you don't have the other adapter........you could make an adapter from a rubber hose (small piece) that has the the same diameter as the required adapter. maybe cut at it a little longer so you could put a clamp around it to prevent it; from sliding up the tube while installing the LU
 

The Force power

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Single port exhaust 1 piece drive shaft gear case, 2:1 ratio used on the 85Hp.
Single port exhaust 1 piece drive shaft gear case, 1,73:1 used on the 125Hp.
As the gear-case where not "labeled" with stamps, the only way to know what you got would be either look for a date stamping in the cast or by counting the revolutions of the drive-shaft v.s. prop-shaft
 
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