Removing powerhead from 1979 I6 140hp.

[madgadget]

I tried last week to remove the power head on my engine to replace the bottom crank seals. I failed

I removed all eight bolts around the bottom of the power head but could not move the power head at all. It appeared as though leg had corrosion around the studs on the power head and so had seized them together.

I then tried putting the nuts back on and using small metal blocks so that by undoing the stud bolts it would leaver on the blocks and hopefully separate the head. Again it did not budge at all.

Help! What else can I do?

 

[madgadget]

Re: Removing powerhead from 1979 I6 140hp.

I have heard that heating may help, but I am concerned that this may affect the aluminium casting of the leg.

Anyone with any experience on this what did you do?

 

[country boy]

Re: Removing powerhead from 1979 I6 140hp.

Are you using a lifting eye , with all of the weight of the motor hanging? are you using penetrating oil? you sometimes can use a wooden wedge to get it moving but you have to have it hanging.

 

[madgadget]

Re: Removing powerhead from 1979 I6 140hp.

I had it hanging on my workshop hoist. I feared If I pulled any harder I'd do damage to something.

 

[daveswaves]

Re: Removing powerhead from 1979 I6 140hp.

I doubt that you could heat enough to make a difference, generally it is a combination of the gasket and the corrosion holding it together. If you have a carpet knife you can try and tap the end into the gasket and then tap it around the circumference with a hammer. The idea is to break the gasket and not gouge the aluminum. Penetrating oil helps if the studs are corroded from salt water use. It is also possible that the drive shaft is stuck in the end of the crank as well. If it is that badly corroded I would remove the lower end first so that you have some wiggle room for the block. Its a good idea to change the water pump impeller anyway and it eliminates damage to the drive shaft end.

 

[madgadget]

Re: Removing powerhead from 1979 I6 140hp.

Yes I have the entire gasket set, everything for the power head, carbs, gearbox seals, fuel pump, impeller etc. I plan to do the whole lot so I know its all done and there wont be any hidden problems. I'll have another go possibly this coming weekend.

 

[blue90HP50]

Re: Removing powerhead from 1979 I6 140hp.

Mad: None of above are wrong! I had same situation and these are the steps I took: Remove lower unit. Use hoist to apply 50-60% lifting tension on lifting eye vertically, spray circumference of block with penetrating oil at any time and let set, use your steel blocks under 6 bolts/nuts and back the nuts down to apply even tension all around, then use a beveled 1 inch wide stiff paint scraper to tap between block and mid-section. It took me a couple of days for my block to release. Additionally, if your water jacket cover around the plugs is NOT leaking do Not mess with it, because there is nothing behind it that can be helped relative to the trouble it is to inspect.(Most bolts will break)
Blue

 

[madgadget]

Re: Removing powerhead from 1979 I6 140hp.

Thanks blue. May have a go this weekend. Spent a fortune in fuel with it weekend just gone so Its unlikely I'll be taking it out again that soon haha

 

[nathanhooper]

Re: Removing powerhead from 1979 I6 140hp.

just out of curiousity, what made you decide to change the crank seals? Was there something wrong? What symptoms was it showing? Just curious because I have a 90hp and I want to keep on top of things with it. thanks.

 

[Chris1956]

Re: Removing powerhead from 1979 I6 140hp.

Mad, Did you get the two nuts in the front underside of the motor? Those are in a small space and need to have the block lifted a bit to actually remove then from the studs.

 

[madgadget]

Re: Removing powerhead from 1979 I6 140hp.

The two front ones by the steering arm? If so yes, by moving the engine left then right I got those out.

I need to change the bottom crank seals as the bottom spark plug is being steam cleaned by water getting to it. (or at least i think that's where its coming from)

Ed