Seized bottom end

keelhauled · 01 December 2009, 06:22

Is it common practice to use an oxy/acetalene torch to free the bottom end on an outboard to change an impeller. All bolts are removed.

m chappelow · 01 December 2009, 09:11

i have known people having to do that at times , but its a bit extreame ,i use boiling water and a big rubber mallet ,or a block of wood and a hammer but with care ,,though having said that i havent had any bother in recent years ,perhaps people are removing or servicing the water pumps more often than they used to .worst engine we had to repair was a volvo penta the one with 2 impellers and 2 water pumps ,,one for the engine and the other could be used as a bilge pump and that was a compleate ba,,,,,d to seperate ,but it had been neglected for years ,

Hightower · 01 December 2009, 09:32

Quote:

Originally Posted by keelhauled

Is it common practice to use an oxy/acetalene torch to free the bottom end on an outboard to change an impeller. All bolts are removed.

If it's for the Yam 75 isn't there a hidden screw under an Anode? I'd check this before hammers, Mallets and Gas Axes

are used.

Hightower · 01 December 2009, 09:34

http://rib.net/forum/showthread.php?...aha+bolt+anode

Hightower · 01 December 2009, 09:37

I knew someone posted a Step by Step guide to stripping a gearbox off a Yamaha leg.

Read and enjoy http://rib.net/forum/showthread.php?...yamaha+gearbox

Hightower · 01 December 2009, 09:41

Quote:

Originally Posted by Hightower

I knew someone posted a Step by Step guide to stripping a gearbox off a Yamaha leg.

Read and enjoy http://rib.net/forum/showthread.php?...yamaha+gearbox

Don't forget that these instructions are for a 200HPDI Yam and not the 75. But I think the mounting bolts for the leg are the same design.

Downhilldai · 01 December 2009, 11:18

Quote:

Originally Posted by keelhauled

Is it common practice to use an oxy/acetalene torch to free the bottom end on an outboard to change an impeller. All bolts are removed.

Propane's cheaper and comes in bigger tins.

Mollers · 01 December 2009, 11:22

Quote:

Originally Posted by Downhilldai

Propane's cheaper and comes in bigger tins.

Burns bigger holes too.

Locozodiac · 01 December 2009, 18:45

Thant's why you need to place lots of ball bearing (salt environment use) grease all around inside leg parts before closing, including all bolts.

keelhauled · 01 December 2009, 19:07

Thanks for the tips guys. The boiling water will probably do the trick. I had found the bolt below the anode so hopefully there is only a bit of corrosion holding it together.

tsnando · 01 December 2009, 19:28

Hello
Be carefull that the leg shaft is not seized to the crankshaft!
Yamaha advises that the spline on the lower leg shaft be lubricated every year!

Cumps

Nasher · 01 December 2009, 20:04

Removing the bottom end of an outboard you've not known very long for the first time can be a real pain if it's not been off for a while.

I've always found that patience is the greatest asset you have to resist the temptation to beat the hell out of it, as you'll end up breaking the cav plate.

If its just corrosion between the two mating faces of the castings, and around the stainless dowels that locate between the faces, then hot water will help, so will tapping around the join with a rubber mallet. Note that's sideways onto the join, not trying downwards on the cav plate.

I always leave a couple of bolts in loose as the bottom end can break free suddenly and you may not be ready to catch it.

If the driveshaft splines are corroded into the crankshaft you really are unlucky, the only way I've found to get these out is to try when the engine is right up to operating temperature.

Regardless of how much I've used the boat I always drop the leg every spring to change or check the condition of the impellor. I take the oppertunity to clean and regrease the driveshaft splines, plus clean the mating surfaces of the castings before putting a very fine smear of silicone grease on them before reassembly. Hopefully this will mean I can get them apart in the future.

Good luck

Nasher.

kitten · 02 December 2009, 09:04

That'll prob be the drive shaft bush half way up the leg. start with fine metal wedges being careful not to work one spot and ruin the mating faces, then move on to pry bars, the some blocks of wood to keep the box level with the leg and finaly use an old scissor jack for the back of the car blocking as you go. Last one I did took 5 hours. Enjoy.

9D280 · 02 December 2009, 12:24

It's not clinging on by the gearshift rod?