water pump replacement '88 150 Yamaha

[fastkenny]

I received my parts and will be replacing water pumps and fuel pumps on my twin 150's this weekend. I got some good info on the fuelpumps, fuel lines etc., I'm looking for info on doing the water pumps.<br /><br />I've read through the Clymer and it looks pretty straight forward. Does anyone have any tips or lessons learned from this job that you really wish you had known at the time? I saw rodbolt's comments about later models, not sure if there are differences.<br /><br />I'm thinking of things like:<br />If the bolts don't budge, what else to try, when to give up (and get a torch, etc) before breaking them off?<br />Tips for getting the lower unit loose<br />Type of sealant for the gaskets? or no sealent?<br />Type of locktite for the lower unit bolts when putting it back together?<br />Do I need a torque wrench?<br />Anything else that caused you to say "Oh S#$%T!" and re-do the whole thing!<br /><br />Thanks for

 

[rodbolt]

Re: water pump replacement '88 150 Yamaha

mmmm<br /> maybe get a manual?<br /> if its a poorly maintained motor you will have a handful.<br /> someplace on here I posted a bolt by bolt replacement proceder. skip the retainer part,<br /> good luck.

 

[fastkenny]

Re: water pump replacement '88 150 Yamaha

thanks, i'll do some more searching<br /><br />I have the clymer manual, but it seems there are sometimes things that the manual doesn't cover. The lowers were taken off a few years ago, hopefully they will come off without too much trouble.

 

[ianyoung77]

Re: water pump replacement '88 150 Yamaha

I have done my 50Hp a couple of times with no real problems. The first time I bought all the gaskets but didn't really need them as they were not sealed and in great condition. I do not use locktite or tension wrench and they were still tight when I did the job again. I guess it depends on your feel when tightening nuts.<br /><br />The clymer manual also recommended removing the propellor which was unnecesary for my model.<br /><br />My main recommendation is longer flushes - since extending from a quick flush to 10 minutes my impeller is lasting twice as long. I also used some MACS flush a few times which may also improve impellor life

 

[fastkenny]

Re: water pump replacement '88 150 Yamaha

thanks, I appreciate the tips<br /><br />It seems some people use gasket sealant, others use oil, some use nothing. There are several diff types of locktite and other products like neverseize that people use on the bolts. Some like lithium grease, others use diff stuff. Sometimes the manual is perfect, other times there might be a better way to do the same job.

 

[rodbolt]

Re: water pump replacement '88 150 Yamaha

I just use water proof grease on the bolts. if you must use never sieze make sure its Tin based or nickel and NEVER copper on an outboard. but do hunt for that post I made. its a bolt by bolt step. I think I even explained the quick easy way to remnove and install the drive key. on the V yamaha no sealants are nessary just some good non metallic based water proof grease. metallic based grease sometimes will cause aluminium to corrode in certain mineral laden waters.

 

[fastkenny]

Re: water pump replacement '88 150 Yamaha

thanks rodbolt,<br /><br />i think i found the post your referring to, posted below, very helpful. Hope to get the boat wet before the stripers show up.<br /><br />BTW, the Clymer specs 29#s of torque on the lower unit bolts. Do you normally measure it precisely? or just get them 'good and tight'? <br /><br />rodbolt:"for the water pump follow the service manual and remove all the bolts including the one under the trim tab. dont forget the speedo sender if used.<br />now with the unit secured in the upright position unbolt and remove the pump housing. if the insert cup came off with the housing remove it from the housing and reinstall it on the impeller by pusing it down while rotateing the shaft clockwise.. now is the interesting part. starting in 95 yammis used a retainer to hold the driveshaft up at idle and nuetral.<br />to remove the retainer I use 2 large screw drivers pressed between the sttel cap and the nylon clip. twist them as you pry. if it moves and stops you willhave to pull up on the shaft and tap the steel back down again. ok now the retainer assy is off remove the impeller and cup. on top of the impeller is 3 sttel rings 2 flat and 1 wavy. save theses and on reinstalling it goes flat wavy flat. I use a chisel and place the cutting edge at the top of the keey and tap downwards and drive the key out. then remove the plate and gasket. if the rubber dam at the back of the pump on the fwd edge of the exhaust cavity is corroding remove it and wire brush it or it can cause cooling problems by wedging the plate and gasket up slightly. ok now install the gasket and plate. now drive in the key with an aluminimum or brass drift then the impeller then the flat ring wavy ring and flat ring now the plastic then the steel cap. now pull up on the shaft while tapping down and locking the retainer. now put the small oring in the pump hsg then the insert. now grease up the large oring groove and install the large oring. now install the housing to the impeller while rotateing the shaft clockwise. now install the bolts and have a cool refreshing beverage. now install the unit making sure it and the shifter is still in nuetral. now bolt it all up and have another"

 

[rodbolt]

Re: water pump replacement '88 150 Yamaha

ignore allparts pertaining to the retainer on the pump impeller unless your unit is post 95. that is the 3 washers and the steel and nylon parts. all else is pertainent.<br />on the torque for the housing to midsection I pull them tight. not gonna make a special tool for it.

 

[blandes]

Re: water pump replacement '88 150 Yamaha

Recently I changed out my impeller on a Yamy 115 . I noticed whoever did this before put the washers and collar on top of the Waterpump housing instead of the insert cartridge. A mechanic told me that these did need to be on top of the cartridge not the housing. I noticed a bit of space between the drive shaft and the hole that it comes up through (water pump housing). Is this normal to have this space?

The mechanic told me that this did not matter because it is all under water during running anyway.

What do you think? It seems there should be a gasket and collar to keep the water from shooting up the drive shaft diluting the grease and waring on other parts.

Is the waterpump under water during running? This seems odd.

Please advise,

Bob