Recent content by 1970Thunderbird

  1. 1

    Anchor points for tubing and skiing

    All, I'm wanting to tow a two-person tube and perhaps a skier, though not at the same time. I have an 80hp Mercury outboard. Since I have an outboard, I bought one of those ropes that equalizes the load between two tow points. It has a pulley so both anchor points bear the load equally. I need...
  2. 1

    Plug wires for a 1978 Mercury 800

    All, I purchased a set of 22" universal wires for my Mercury outboard. I chose this set because it was the only one that had the proper length. One end has the usual plug boot, while the other has...
  3. 1

    1978 Merc 800 won't idle below 1200 RPM

    Hey all, My 1978 Mercury 800 won't idle below 1200 RPM. What I mean is, my idle adjustment screw is positioned to give it the lowest idle possible, and my motor still won't idle below 1000-1300 RPM. Is there an adjustment somewhere else on the motor? The plastic piece on top of the top carb...
  4. 1

    Wiring an hour meter to a 1978 Merc 800

    Hey all, I'm trying to wire in an hour meter to my 1978 Mercury 800. I'd like to run it into my wiring harness, which has seven wires: black, white, grey, orange, red, yellow and brown. Which one is the accessory wire? And am I correct in assuming that it would power the meter only while the...
  5. 1

    Torque specs for the exhaust

    Hey all, I can't seem to find these torque specs, mainly because I'm exactly sure what this piece is called. It's on the exhaust side, beneath the exhaust cover plate. I believe it's a deflector of some kind, and also a cover for part of the cooling system, perhaps. It's on a 1978 Mercury 800...
  6. 1

    grease in the piston pin

    Hello all, when I had my block machined, the machinist also put new needle bearings in the piston end of the crank. To hold them in place while installing, he said he used purple lithium grease. I've heard that this isn't a good thing, as the grease won't easilt come out, thus preventing the...
  7. 1

    Bead blasting and fitting pistons

    Hey all, I just got my block back from the machinist and I'm ready to start putting her back together. While I was visiting with him, he suggested I sand or bead blast the exhaust side of the block, including the water jacket cover, to remove the carbon deposits. What do you guys think? I'm a...
  8. 1

    Where to buy Pro Marine pistons

    Hey all, I'm looking to purchase four Pro Marine pistons for my Mercury 800. I don't need the Pro-V coated ones. I need the 9000 series, specifically the 9015 and the 9030. However, I can't seem to find a really reputable online place to order from. All the sites I find, I try to pull up...
  9. 1

    Boring a '78 Mercury 800

    Hey fellas, My motor came apart quite easily. I flew it up to Poplar Bluff, MO yesterday and handed it over to the machinist. He's already bored the first three cylinders to 15 thousandths over standard. While boring the fourth cylinder, he discovered a gouge. In order to get the gouge out, he...
  10. 1

    Separating the power head from the lower unit. '78 Merc 800

    Hello again, friends. My engine lifting eye arrived today, so I immediately tried lifting the power head from the lower unit. I'd previously disconnected the 6 bolts that hold it to the lower unit, as well as wiring, hoses and other parts. I also removed the nuts from the two bolts up front...
  11. 1

    Proper compression for a '78 800

    Hey all (again), I had a sneaking suspicion that part of my lack of power under load might have been something other than the prop or fuel, so I ran a compression check. Here are the results. cylinder 1: 95psi 2: 95psi 3: 85psi 4: 65psi I take it have either a bad set of rings or a bad head...
  12. 1

    1978 80HP Merc gets bogged down.

    Hey all, I'm back again. I've replaced my stator, trigger, internal harness. The motor wouldn't start, so I had to set the timing. Now the motor runs pretty well. I had it on the lake this weekend and noticed a few things. The motor dies when it goes into gear. I assume this is an idle...
  13. 1

    Is my prop the problem?

    Hey all, I recently replaced the trigger, stator and internal harness on my 1978 Mercury 800. It's mounted on a 1970 Thunderbird Seminole. I was pleasantly surprised to discover I was getting close to 5300 rpm out of the motor at idle. I thought I was ready to really fly across the water...
  14. 1

    '78 800 won't shut off with the key

    Hey all, First of all, thanks to all who helped with my issues regarding my new trigger and stator. I've got it timed right and it fires right up on the first try. But I now have a new problem: my key no longer shuts off the motor. Everything else seems to work fine, but the key won't kill the...
  15. 1

    '78 800 won't start with new trigger, stator and internal harness

    Hello all, A few weeks ago, I had my boat out with my new-to-me Mercury. It cranked and ran well, but didn't seem to have any top-end power. When I got back home, I gave it a look over and noticed that almost all the wiring was shot. I was amazed it even ran. I ordered a new trigger, stator...
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