Force 150 5Cyl Impeller Replacement

[alpha1]

I've got a 1992 Force 150 HP 5 cyl motor with less than 100 hrs on it...no really! I need to replace the impeller. I've got the manuals, read all the posts. Everyone says it's easy...but the manual doesn't really show how to drop the lower unit to access everything. Can anyone offer details on exactly what bolts to loosen and what to watch out for?? Also, this engine has sat largely idle for several years. I'm going to check compression, replace gaskets on carbs, run the gas additives etc. Should I also replace prop seals??? Anything else I should consider doing. Also are there manuals or diagrams that are more detailed that Clymer or Seloc??

 

[roscoe]

Re: Force 150 5Cyl Impeller Replacement

Actually the Clymers manual is pretty good for the Force engines, a lot better than the Seloc.<br />Of course a factory service manual would be best.<br />Check to see if they are still available from Mercury, at this site:<br /><br />http://www.mercurypartsexpress.com/PartsExpress/ProductSelection/ServiceParts/sph ome.asp?CID=<br /><br />Do you have a Clymers?<br />If so,<br />Remove sparkplug wires. <br />propeller removal, page 398.<br />gearcase draining, chapter four.<br />Shiftrod pin removal, page 406 and photo 19 on page 406.<br />Remove exhaust snout, 2 bolts, page 406.<br />Remove bolt inside exhaust snout cavity.<br />Remove (edit) 6 bolts from under the cavitation plate, that go up into the midsection of the motor.<br />There is an excellent exploded view of the gearcase on page 452.<br /><br />I wouldn't bother with the prop seals.<br />But put new gaskets on the drain and vent screws when you change the lower unit oil.

 

[alpha1]

Re: Force 150 5Cyl Impeller Replacement

Roscoe, Thanks so much for the info! Yes, I do have the Clymers but it doesn't quite walk me through it like you did. Btw, that exploded view of the crankcase made me nervous...I pictured hundreds of little pieces falling out when I drop the lower unit.

 

[WhiteHorse]

Re: Force 150 5Cyl Impeller Replacement

Facing the lower unit from the back of the boat...<br />1) Look behind the lower unit in the recess beneath the pivot housing. There is a linkage that has a pin held in by a cotter pin. Remove the cotter pin and the retention pin. <br />2) Remove 3 1/2" head bolts from the left side of the lower unit (going up into the midsection) and then remove 3 more 1/2" head bolts on the other side. <br />3) Remove the triangle shaped trim tab nose cone right dead out in front of you. It has a large 5/8" head stainless bolt behind the tab and a 1/4" head allen bolt right up inside the spout at the back. The tab will come off now. <br />4) Get a floor jack or a sober buddy to hold the lower unit in place. <br />5) Look up in the recessed area where the nose cone was. There is a 1/2" head bolt straight up in the middle there. Remove it. <br />6) Now the lower unit will drop. If it doesn't drop immediately, just tap it with a rubber mallet and it will fall. Make sure your buddy is there holding it, you don't want to snap the skeg off.

 

[roscoe]

Re: Force 150 5Cyl Impeller Replacement

Oh yeah, there are 6 bolts on the 150. Thanks WHM<br /><br />Nothing should fall out when you drop the lower unit. Everything is bolted in place.<br /><br />Good Luck

 

[alpha1]

Re: Force 150 5Cyl Impeller Replacement

Thanks for the info guys. It took a while to figure out that the impeller was on the TOP of the LOWER UNIT. I was assuming that it must be way up high near the pee holes. The seat for the slpine did fall out and also the rubber seal where the water flows through....but no big deal. We had the boat out on the lake by 3pm and it fired right up!!!!<br /><br />One more question though. After the boat was on plane and we eased back on the throttle a little, the motor made a medium picthed humming noise....it sounded a little like wind blowing through a pipe. I couldn't locate the origin. Is this familiar to anyone?? Anything to be concerned about?? We did run a little rich because this was the boat's first outing in some time.

 

[alpha1]

Re: Force 150 5Cyl Impeller Replacement

I did have some time to think about it last night. When we put the drive shaft back in we did lube it up with 2-4-c multi lube. Page 406 of Clymers has a big Caution before step 8 that says not to lube the drive shaft. Does anyone know what hydrolic lock is? Or preloading the driveshaft and crankshaft? Could this be causing the hum? Thanks.

 

[roscoe]

Re: Force 150 5Cyl Impeller Replacement

You should lube the splines of the shaft, but not the end (top) of it. <br /><br />Hydrolic lock- is something they warn you about in all the manuals. ?? sorry<br /><br />By putting grease on the top of the driveshaft, and inserting it into the bottom of the crankshaft, you are trying to fit a 25.1 inch drive shaft into a 25" space. This would put alot of pressure on both the driveshaft and the crankshaft and bearings.<br /><br />Hmmm. Hopefully WHM will be along to add some of his expert knowledge to the subject.

 

[WhiteHorse]

Re: Force 150 5Cyl Impeller Replacement

Thanks, I feel so loved here! <br />When you put grease on the top of the drive shaft, you create a pocket of expandable material that will put pressure downwards on the driveshaft when heated during operation (heat it and it expands, right?). Easy enough to figure out that when it expands, it will push down on the driveshaft and up on the crankshaft. Not a good thing for either one. <br /> A little grease on the splines, etc., is a good thing because it will reduce a little friction on the splines and it will keep the driveshaft from rusting solid up in the crank. About half the blown Force outboards in the US end up on my doorstep sooner or later, so if you motor doesn't appreciate it, at least I will. However, packing the top of the driveshaft with grease or the bottom of the crank with grease is a no, no.

 

[roscoe]

Re: Force 150 5Cyl Impeller Replacement

WHM, you ARE loved here, and on ebay. <br /><br />Very few wrenches come to the force forum to give indepth help. I try to help people with the basics and refer them to other sources, but have little firsthand knowledge or experience.<br /><br />As springtime nears, there will be more than enough boaters with weak Forces, that will need your help (hopefully not me). Please keep checking in, we need guys like you.

 

[alpha1]

Re: Force 150 5Cyl Impeller Replacement

Yes, thanks to both of you for all the help. It's probably trite on this forum but here goes.....May the Force be with you!