hustler57 Posted August 16, 2006 Share Posted August 16, 2006 Hi People, Anybody know how you remove the engine block from an early 70's 140 Johnson so the cylinders can be rebored? Link to comment Share on other sites More sharing options...
Grantm Posted August 16, 2006 Share Posted August 16, 2006 Its actually pretty straight forward from memory. Just remove the bolts that attach it to the leg, plus any connecting hoses and wiring and it will just lift off. The drive shaft is not physically connected to the motor end and easily seperates when you lift the block. Be warned you may snap some bolts if they are corroded which will need repairing. Dont panic if that happens cause its also pretty easy to get them out if snapped. Its been a loooong while since ive done one but i think thats it ! Link to comment Share on other sites More sharing options...
kingpig Posted August 17, 2006 Share Posted August 17, 2006 First disconnect gear change shaft under the power head. Undo the lower cowling and it should remove in two pieces. Try to keep the electricals connected togther as much as possible by removing the starter motor and power packs still connected. Putting this back together is a jigsaw puzzel. Remover the fly wheel. You will need a special puller for this as it will be locked tight on the taper of the crank shaft. Also when you put this back make sure it is tight ( big pipe on spanner tight). If it is not the fly wheel will move and shear the small woodruf key that keeps the engine timing set plus damage the crank. You should now be able to remove the crank case bolts and lift the power head off (if I have not forgotten anything). If you are planning to put new pistons be carefully how you assemble them to their con rods. There should be a small hole in the web of the con rod that goes into the small end bore. This hole need to be on the fly wheel side of the assembled piston and rod. Oil feeds through this hole to lubricate the small end bearings. If the hole is upside down no lubrication and the motor will seize quickly. I would recommend changing the small end and crankshaft bearings while you have appart. You will aslo need a gasket kit for the power head. Take the side cover off the block and clean out the cooling jacket as best you can as well. Tips:- taking the fly wheeloff is hardest part. Make a puller to suit. Wrap a rope around the flywheel several time and then tie it something solid to stop it rotating when you remove and replace it. Get some plastic bags and put different bolts and pieces into the bags and lable them with good descriptions. This will greatly help reassembly Good luck Link to comment Share on other sites More sharing options...
hustler57 Posted August 18, 2006 Author Share Posted August 18, 2006 hey fellow thanks a lot for all your advice it helps a lot. im up to taking the bolts off ..thanks Link to comment Share on other sites More sharing options...
codszilla Posted August 19, 2006 Share Posted August 19, 2006 hey fellow thanks a lot for all your advice it helps a lot. im up to taking the bolts off ..thanks I second that, good reading thanks kingpig. Link to comment Share on other sites More sharing options...
hustler57 Posted August 21, 2006 Author Share Posted August 21, 2006 hey fellow help im stuck... where and how many bolts are holding down the block ???? in which locations are they ????? Link to comment Share on other sites More sharing options...
kingpig Posted August 21, 2006 Share Posted August 21, 2006 The engine is laying on it's side. The back where the spark plugs are is the head. Behind this is the block and then the crank case is closest to the transom of the boat with the carbies attached. This hole unit (power head) is held down by a series of bolts that are threaded into the leg of the outboard. If you have managed to remove the lower engine cowling. It should be two pieces that you needed to unsrew to take off then you were far from the bolts holding the power head on. PM me some details. I may have a manual that could help. Cheers Link to comment Share on other sites More sharing options...
hustler57 Posted August 22, 2006 Author Share Posted August 22, 2006 ok thanks kingpig il let u know how i go. and the motor is still on the back of the boat.. and i am in the mortdale area in south west sydney and do u know of any good people who can re bore the cylinders and supply over size pistons ??? Link to comment Share on other sites More sharing options...
kingpig Posted August 23, 2006 Share Posted August 23, 2006 You should be able to get the pistons from Hunts Marine in Hurstville. Not the show room on the heighway so call them and get the address for there spare parts department. The motor should have a compliance plate on the bracket that attaches to the transom. The numbers on this plate will identify the engine. Pistons usually go up in size by 0.030 thousands of an inch. I bored my old engine myeslf but I would not recommend this if you do not have access to the equipment. Try to find somebody that rebuilds motor bike engines they will be able to do this but I do not know anyone specifically. Some of the other fish raiders may. Try and post this as a specific question. Cheers Link to comment Share on other sites More sharing options...
johnno Posted August 23, 2006 Share Posted August 23, 2006 HI Hustler There is a place near you that i have used over the years doing full car engines boring,head work , They are in Barry ave Peak Rebores hope this does not cause a hassle by posting what i have posted Link to comment Share on other sites More sharing options...
hustler57 Posted August 24, 2006 Author Share Posted August 24, 2006 ok thanks guys this is starting to become a real pain im thinking it may have just been easier to get a boat mechanic to do the hole thing....hmm does any one know any mobile boat mechanics that could come out to mortdale and finish taking the block off ???? we have no problem putting it all back together again after it gets rebored ect ect::::: but its starting to become a pain Link to comment Share on other sites More sharing options...
george.s Posted August 24, 2006 Share Posted August 24, 2006 ok thanks guys this is starting to become a real pain im thinking it may have just been easier to get a boat mechanic to do the hole thing....hmm does any one know any mobile boat mechanics that could come out to mortdale and finish taking the block off ???? we have no problem putting it all back together again after it gets rebored ect ect::::: but its starting to become a pain mobile mechanic brent 0421271967 he comes from that way Link to comment Share on other sites More sharing options...
hustler57 Posted August 24, 2006 Author Share Posted August 24, 2006 ok thanks george il call him tomorrow and have a chat to him regarding my outboard.. thanks again. cheers Link to comment Share on other sites More sharing options...
Guest bluecod Posted August 24, 2006 Share Posted August 24, 2006 Hustler - quite a few years ago I completely rebuilt my 55 Mariner and from memory was getting frustrated like yourself - until my local mechanic [shortlegs] told me about the inner exhaust housing inside the leg unit. There was no way the block was coming off until the inner exhaust housing was first removed. Now I don't know if your Jonno is the same style of design but it could be worth investigating. Link to comment Share on other sites More sharing options...
hustler57 Posted August 26, 2006 Author Share Posted August 26, 2006 ok thanks for the advice. im going to get the boat mechanic out to finish the rest as its been a while since ive gone fishing and the fish in my fish tank are starting to look like they could be caught Link to comment Share on other sites More sharing options...
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