85 Johnson 150, big time help. need to removal powerhead and it is stuck

[firemann2003]

Got new rings and leaf valves. Trying to remove powerhead and it won't let go. Removed 2 bolts and nuts under the front, the two just under the exhaust housing in the back and the six long ones coming up from the bottom, the problem is that the two back ones, of the long ones, broke off at the head of the bolt. The powerhead will now not lift off. Can the front crankcase come off without removal of the powerhead? I'm assuming it can't. Does anybody have any ideas how to get the powerhead to come off? I will now need to cut those bolts off and remove them from the holes in the block. The front of the powerhead will lift up a tiny bit but the back will not budge.

 

[R.Johnson]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Do you have an engine hoist so that you could keep tension on the back side, then spray around the joint with penetrating oil. If you could create a gap in the joint, you could try hard wood wedges.

 

[firemann2003]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

trying to raise powerhead just pulls up entire motor, no matter what I have tried I can not get a gap to open up along the back edge.

 

[Texasmark]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Look closely to insure that you didn't overlook a bolt somewhere. Have done it many times; was sure I got em all and sur-nuf one left.

Mark

 

[firemann2003]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

according to manual, I got them all and looking has not turned up any more.

 

[R.Johnson]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Put the nuts back on the two studs under the exhaust cover, just start them on, not all the way. Try putting on steady pressure with a right angle pry bar. The gasket is probably holding also.

 

[Walker]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Those 2 that broke are probably corroded their entire length. If so you really have a problem getting them loose so the powerhead will come off. Can you get any gap at all anywhere under the powerhead??

 

[imported_lorin]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

If you have a hoist, most of the methods described above may work better if you first lift the engine upside down so it is suspended by the gearcase with the flywheel about a half inch off the ground. That way you have the entire weight of the powerhead helping you. Also, penetrating oil will be more likely to pass down around the broken bolts. You might also try oxy-acetylene torch around broken bolts. The oil by itself often works on a drive shaft stuck in the crankshaft, but sometimes can take a week or more.

 

[emdsapmgr]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Am assuming that you have a flywheel puller and that you can put a chain on it. If you don't have an engine hoist, chain the flywheel/block to the rafters of the garage and then crank the front of the boat trailer up. This will lower the engine midsection and put pressure on the chain to lift the block slightly. Once you have it suspended-rocking the chain is also helpful. Removing heads, carbs, vro and starter first, will improve the access to the base of the block. Make sure you have the shift rod disconnected. Can you wedge a putty knife between the block and midsection at the front? Once you get the powerhead off, you may be able to grab the broken bolts with vise-grip pliers and twist them out. You won't be the last person to struggle with this problem.

 

[firemann2003]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

I can get about an 1/8 inch gap on the front of the powerhead it than tapers back to where the very back bolts go up through the midsection to the block. Have a couple of free hours so I will try wrestling with it somemore today.

 

[Texasmark]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Couple of things.

Overhead lifting from the garage rafters might be more than the rafters are rated for. I personally would rent an engine hoist at the local rental center and do the lifting from the floor. You don't know till they fail and when they do you could have the whole roof in a tissy and stuff falling down on you.

If you can get the powerhead off with some stud showing, I'd get a premium penetrating oil (Kroil is one, have heard of a thing called Monkey's Milk also) and let them soak for a few days.

Vise Grip brand pliers has a new plier out now that is made just for getting studs out. Jaws look nothing like the old ones that have been around for years. Work great and really grip.

I'd start by putting back and forth pressure on the studs and keep increasing the pressure; in a rocking motion.

Impact is super for dislidging things, so you might try taking a hammer to the plier handles and smacking with a right smart whack back and forth, back and forth, till its starts moving.

Otherwise heat will work, but with heat you have to worry about what you are going to burn up in the process.

HTH

Mark

 

[Hotrods]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Had the Same problem, Wound Up tearing the studs right out of the Power Head. Had them repaired at the shop. Problem with mine I seen after tearing them out was.. the rear slots wear tapered and allowed tons of crude to build up in there over the years and basically weld the studs into place...

If I had to do it again I would use more WD and work it for a few days.. not hours..

 

[firemann2003]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Constant pressure with hoist and pressure on the two studs just under the exhaust cover still not getting it loose. Any other ideas? No gap between block and adapter to get fluid down the hole to break bolt shafts free.

 

[emdsapmgr]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Is the lower unit still on the engine?

 

[firemann2003]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Yes lower unit is still on the engine. Just in case, god forbid I need to, does anybody no where a supplier is that I could get a crankcase for this engine?

Johnson J150TXCOS 1985

 

[Solittle]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

If you live in or near a large city hit the yellow pages and look for a machine shop. Call and describe your problem. A good shop will have tricks that we never even heard of. There is one near where I live and the owner is in his mid 80s. His hands are black with grime, he usually has a 3 day beard, chews the stub of a cigar - - - if it is made out of metal he can fix it or make it.

 

[imported_lorin]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Crankcases are not interchangeable, or at least they're not supposed to be. They are machined to the block/cylinders. Has anyone ever tried switching to a different crankcase and did it work? I've never tried it. Again I would suggest you tip it upside down and apply penetrating oil and heat. It may take a while and no guarantee it will work but seems like nothing to lose at this point.

 

[emdsapmgr]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Suggest you remove the lower unit. You will need to in order to replace the water pump anyway. Might as well get that factor out of the total problem equation.

 

[R.Johnson]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

Some how you are going to have to break that corrosive bond on those broken stud's. You could put the engine upside down as suggested. You could then put a dam around these stud's with modeling clay, and apply muriatic acid with a rubber syringe. That would be much more agressive on that bonded rust, and lime then penetrating oil. Muriatic acid is available at any of the larger hardware store's, and it is cheap. Muriatic is not as nasty as the other acid's in their pure form, but will really go after rust, or lime. Look in the store's garden department. Are both broken bolt's on the same side, not that it really matter's?

 

[firemann2003]

Re: 85 Johnson 150, big time help. need to removal powerhead and it is stuck

The broken bolts are on opposite sides. Will try flipping the entire thing upside down today and soak it with the muriatic acid. I am assuming this will not hurt the aluminun casing?