1992 King Cobra 7.4L - Overheating--Part II

[07caddy]

Starting to locate some of the impeller after flushing from thermo housing and flushing the steering cooler. (Pic #1)

The port on the right side of that is where the pieces have been trickling out (Pic #2). I haven't seen any water on the left port...

In Pic #3, I see impeller pieces in the lower drive unit and that brings me to my question of the day!! (I ordered an OEM service manual and it should be here in a few days).

Questions:

1. Can I remove that lower unit by removing the 6 bolts, drop it, and get down in there to remove the remaining pieces of the impeller? I see pieces through the holes in the side of the unit (pic 3)

2. There's a drain plug on the left side of the unit, so do I have to drain it first? If so, can someone provide info on replacement gear oil? Can I use Mobil One gear oil like I do in my truck?

3. Assuming there's gears and a bunch of other stuff in there, is it easy to put back together once I get it apart?

Thanks,

Mike

[Lou C]

Starting to locate some of the impeller after flushing from thermo housing and flushing the steering cooler. (Pic #1)

The port on the right side of that is where the pieces have been trickling out (Pic #2). I haven't seen any water on the left port...

In Pic #3, I see impeller pieces in the lower drive unit and that brings me to my question of the day!! (I ordered an OEM service manual and it should be here in a few days).

Questions:

1. Can I remove that lower unit by removing the 6 bolts, drop it, and get down in there to remove the remaining pieces of the impeller? I see pieces through the holes in the side of the unit (pic 3)

You're saying there are impeller pieces in the water intake holes? I suppose it's possible, but in oder to get them out you'd have to either 1) remove the drive and hook up water muffs and try to blast em out with water pressure (I have done this with barnacles growing in the water intakes, break em up with a small screwdriver and blast em out). Or 2) if that doesn't work, the upper and lower drive units have to be separated, and then the water intake area can be accessed after removing a cover for the water tube (#35)

http://www.dougrussell.com/partscata...1137,1138,1139

I'd really try to blast em out with the water muffs, because pulling apart a drive is not a good job to start with for someone new to working on sterndrives.

2. There's a drain plug on the left side of the unit, so do I have to drain it first? If so, can someone provide info on replacement gear oil? Can I use Mobil One gear oil like I do in my truck?

The drain plug is part 25, if you do change the gear oil, use either the Merc Hi Performance oil or the OMC HPF oil if you can find it. Make sure you change the gaskets for the drain and fill plugs because they can leak and let water in the gear oil (bad). I do not know the procedure for re-filling those cone clutch drives or how much gear oil they take but if you do it wrong, you will ruin a VERY expensive drive, and one that is hard to replace. SO if you want to do this, take some time to find what oil to use for sure, how much and what procedure. You need a gear oil pump too.

3. Assuming there's gears and a bunch of other stuff in there, is it easy to put back together once I get it apart?

Not something to play around with at all, like a manual transmission. All I have done to mine is change the gear oil, anodes, impellers, and make sure the shift system is set up right. Also I do the yearly drive R+R to grease the ujoints, gimble bearing and check the bellow for water. Any more involved drive work than that I take it to the shop. Just be careful and get all the information you need first.

Thanks,

Mike

PS I was lucky, I got the OMC factory shop manual for mine when you could still get em....

[07caddy]

Lou,
I hooked up muffs and tried to blast the impeller piece(s) out--no go. I can only see one piece but assume there are others because I picked out several with tweezers. I may take it to a local shop and have them separate the upper and lower units to get the rest of the garbage.

I had a heck of a time finding a new impeller, gasket and seal. Couldn't find the housing or stainless steel cup that sits inside the housing so I had to use my old one--and it isn't in the best shape. All of this apparently comes in a water pump repair kit (#13 on the DR website drawing for the water pump system). I ordered the kit from DR and the next day received an email telling me the parts are NLA.

The challenge of sourcing OMC KC parts just hit home

[HT32BSX115]

The challenge of sourcing OMC KC parts just hit home

You SHOULD be able to find things like impellers, housings, & gaskets etc though........

You may have to call around or get with BRP's customer support. http://epc.brp.com/

Yeah......many of us have "been there-done that" It just gets worse too, sorry to say.......

[a70eliminator]

separating the upper and lower units isn't that big a deal, remove the trim tab because there is a bolt hidden beneath it that has to come out, but yea it's basically six bolts and then jiggle and pull it off, the lower will have the shift rod sticking 7" straight up, the driveshaft, couple stacked spacers and a seal, other than mentioned no loose parts or gears are going to fall out, don't be afraid to do it, it can be stubborn if alot of corrosion present but once you get it moving she'll seperate.

[07caddy]

I have a lot of things to do on my list (e.g., spark plugs, fuel filter, lube) so may separate the units this weekend.

One of my neighbors called the cops on us because our boat has been parked in front of our house for more than 24hrs!

So I need to put it back in storage for at least 24 hrs before I can bring it back.