TOPIC: 1961 Merc 800

I am new to this forum. I am confused about my Merc 800 motor, but maybe I have found the answer. I have a 61 Merc 800 motor I bought at a farm auction. The motor is super clean, turns freely, and has no hint of corrosion. The foot was removed, but was included. Water pump housing missing, since bought new one. I didn't know if it was a running neutral, or dockbuster type. It does have 2 starter solonoids, so I guess its dockbuster version. I have since run across another boat with what looks like an identical 800 merc, but it has neutral, as you can spin the prop without spinning the motor, but the control only has 1 lever, is it shifted and accelerated with 1 lever? Will this control work with my motor. I didn't get wiring harness or control with my motor. I love the old mercs, and have a few, including a 58 Mark 58A, and a pair of Mark 35A's.

DR for sure.

Hello,

As Dave states, the Merc 800 pictured is a Direct Reverse model. The Merc 800 that you just found is a Full Gear Shift model. Yes, the single lever factory FGS remote controls do control both the shift function and throttle function. Unfortunately, a FGS remote control is a poor match to a DR model, but hopefully you can locate the correct control (only utilized with 1960 and some 1961 Direct Reverse models).

Regards,
Joe
www.fergusonpoolemarine.com

I have a question on the DR Mercs. Are they the only ones with the pipe like exhaust/water relief on the mid rear? Or on FGS motors also? Curious as be easy to spot a DR motor.

Robby321 wrote:

I have a question on the DR Mercs. Are they the only ones with the pipe like exhaust/water relief on the mid rear? Or on FGS motors also? Curious as be easy to spot a DR motor.

Yes, all the 6-cylinder Dockbusters have that configuration with the exhaust relief pipe, and exposed nuts for the powerhead mounting. Note there were only 6-cyl Direct Reversing motors, the 4-cylinder tower might look similar but in most cases are FGS. Very old 4-cyls didn't have a shift at all (only Fwd), but that's a different Beast.

Very obvious on the '64-and-older FGS models is the "tin" wrap-around cover over the powerhead nuts, fastened with (2) stainless slotted-head screws at the Fwd end of each side.

Attached is a pic of one of Doc Frankenmerc's beautiful restorations of an 80hp FGS, the differences are a'plenty.

Cheers.......ed

Thanks the knowledge Ed! And that looks like Petes woodie there! Damn, I like to see that boat, meet Pete, and aint seen the Doc a while either. Been busy and have to shoot up there for a BS session winter!

Robby321 wrote:

Thanks the knowledge Ed! And that looks like Petes woodie there! Damn, I like to see that boat, meet Pete, and aint seen the Doc a while either. Been busy and have to shoot up there for a BS session winter!

That particular 800 FGS is on a Tolly, beautiful in its own right.

But yeah, Pete's motor looks like that one and is very Purty. And what a screamer with the "Doc Frankenmerc Special" 1000 powerhead hiding underneath!!!

Been a month or so since I've been down there for a visit, probably gonna swing by the Doc's in the not-too-distant future.

Cheers......ed

Thanks for the help, I see the difference in the exhaust vent port. The motor has mint 3 blade quicksilver prop, but water pump was disassembled, missing water pump cover. Does any one have correct control and wiring harness?

More confusion, I just bought a Jav Lyn boat with a 850 cloud white mercury. Its got two levers, one for shift, and one for throttle, but the controls are older looking quicksilver controls. Since this motor wasn't mounted on the boat, am I to assume this is not the motor that came on the boat. I believe its a long shaft model. Maybe the boat came with a smaller motor, mark 58 maybe?

wow a short shaft with extention kit. got a pic of the controls? do they have 2 cables? there was a peapod style single lever 2 cable box back then.

will send pic tomorrow, but they are two cable, two lever,green quicksilver with key on side. look identical to my mark 58 controls.

back the motors did not come with controls . so any that fit would be used . the thing to look at is the electric cable. that is unique to that motor.

After getting the motor out of the truck, I see it has a decal that says single lever full gearshift. I don't think this motor came on my boat, although it came with it. As the transom of my boat is about 17" tall, I think I need a short shaft engine. I could take extension out of this motor and use it, I may get an older motor, maybe a mark 78 or a mark 58. I don't know if I want to deal with the dockbuster style mark 78.

Even though the FGS motor came from the factory with a single-lever control, the older dual-lever box would work as well. Providing the electrical plug matches the 800's wiring harness. Easy enough to check that.

If the FGS 800 was a straight-forward longshaft conversion with the 5" Bay Marine extension kit, it would have had a stub-shaft that fit on top of the driveshaft. It also would have had a shift shaft extension along with longer L/U studs, water tube extension, etc.

If that's the case, then all you'd need to do is completely remove the longshaft kit and reassemble as a short shaft. You may need to find some shorter L/U studs to replace the ones from the L/S kit.

The other possibility is, that they used a longshaft lower unit along with the L/S kit, and so there wouldn't be a driveshaft extension to remove. So you would either have to find a S/S L/U, or pull the L/S driveshaft out of the existing L/U and install a shorter driveshaft.

Last option once the driveshaft is out, you can get it cut and re-splined.

Hopefully you'll find the driveshaft extension stub shaft, and it'll be a simple conversion.

You're just a few minutes of wrenching away from finding-out!

The suspense is killing me!!!

I picked up a 73 boat with a 73 115 Mercury. It also is a short shaft with the extension housing, single lever controls. Ill pull the 85 apart and see whats in the lower unit.

You realize that S/S 115hp midsection is highly-desirable and probably worth $500 or more by itself!

Note this would be a blue-band motor if it has the highly-sought-after mid, which has a thick removable tuner plate under the powerhead, with 2 large rectangular ports.

99-c.i. Short Shaft Inlines are in great demand 'cause they have the power to get a good turn-of-speed on a high-performance boat, and the shorter shaft means you don't have to jack-up the motor as far (good for your center of gravity).

Congrats on a good find!

It is a blue band, appears in good shape and ran 2 years ago. These old boats are dirt cheap in Kansas. It does have a welded break in part of motor below powerhead, but above midsection. Also came with 3 props, one of which is plastic 4 blade, never seen one of those. I want to run a cloud white era motor on my JavLyn, to be more period.