Need help with impeller on 1973 merc

[jasonLee]

hello....I have this 1973 50 horse mercury ...title has a manufacturer ID no. 3721758 .....serial no. on motor is the same . So I need to purchase an impeller ..... maybe someone could guide me in the right direction so i dont mess up from the git go.......ALSO I have this amazon credit i need to use ,so to make things more complicated I want to go through amazon....if possible....anyways I got this old motor that is and always has been GREAT!....but getting someone to work on it is not GREAT....so i will just do this myself ...(the last time i had someone work on it they kept it for 6 months ....rewired everything and then couldn't it to turn over ....so they gave it back with NO charge....and I fixed the wiring myself lol......so i am going to replace the impeller myself and see what happens ......but getting the right part is step 1....lol.....
thanks

 

[racerone]

Most Mercury dealers will have a QUALITY part in stock.----Just give them your serial # and they will hand you a good impeller.

 

[fitz73222]

47-89983 same impeller from 1957 to 1997, all 4cylinder models 40-50 hp

 

[jasonLee]

thanks a bunch...hey that helps....the serial number was not getting me anywhere.....so this kit looks good then (lots of choices now) ....hope its ok to post this

Amazon.com

 

[timguy]

Yes not sure of the "quality" here, but will certainly get you going. In the old days impellers were made of pure rubber but today they are mostly synthetic, they don't last as long and will melt if run low on water. If you go with an OEM Mercury impeller you will probably get more life and reliability. It's going to cost you more but likely not a whole lot of difference.

 

[racerone]

The 73 model 50 HP ( like many motors ) does NOT have an overheat warning horn.-----It does not have a feature to shut down the motor in case of over heating.-----This is why I suggest a QUALITY impeller.----Replace it every 5 years !

 

[timguy]

Amen

 

[jasonLee]

ok...well i just ordered one from here ....that ought to work ...lol....... (had to sell the amazon credit to my wife for 50 cents on the dollar...)

 

[FishKiller49]

hello....I have this 1973 50 horse mercury ...title has a manufacturer ID no. 3721758 .....serial no. on motor is the same . So I need to purchase an impeller ..... maybe someone could guide me in the right direction so i dont mess up from the git go.......ALSO I have this amazon credit i need to use ,so to make things more complicated I want to go through amazon....if possible....anyways I got this old motor that is and always has been GREAT!....but getting someone to work on it is not GREAT....so i will just do this myself ...(the last time i had someone work on it they kept it for 6 months ....rewired everything and then couldn't it to turn over ....so they gave it back with NO charge....and I fixed the wiring myself lol......so i am going to replace the impeller myself and see what happens ......but getting the right part is step 1....lol.....
thanks

I'll check for you when I get in the shop tomorrow see if I can get you a part number

 

[jasonLee]

OK....well I got the new part through marine engine using the number part 47-89983T , the T on the end is suposed to be the OEM number .....ANY ways i have the lower unit off....the old impeller is off...and it has a slightly wider key slot than the new part..???.....and even without the key in ...the new part doesnt drop in place very easily....you can get it to go down without the key but its real tight and doesnt come back up after that without some teeth clenching ..??.....with the key in it will be even tougher ...the old one drops right back in place easily.....and frankly the rubber looks just as nice on it as the new one and it fits real nice and tight with the blades tight against the housing wall ...no cracks ......I dont think it was all that bad.....perhaps there is an obstruction i cAn blow out..../the new part seems iffy to get in with key slot problem and the otherwise tight fit..........maybe the shaft could be sanded or something ?? here is a pic of the old one

 

[racerone]

The new part is not ---" iffy "----And you are not aware of how these pumps work.----The vanes on the old impeller have taken a " set " and is scrap.----Put the new impeller on the shaft with the key.-----Put a wee smear of grease inside the pump housing.-----Now lower the pump housing down on the impeller.-----Push down on the housing while rotating the driveshaft.----The pump housing will slide down.-----Button it all up and go fishing !

 

[jasonLee]

no...i dont know jack....but the new impelar hits on a seam in the shaft right before it hits the key....getting past that spot is difficult .....the old one just slides right in place....like i said even doing it without the key in place is tough......and the key slot is wider on the old one ...anyways i can give her hell and maybe get it on....but if not It takes some prying to get it back off...thats where i could trash the the new part if not carefull.....there are videos and i have tryed to make myself "aware"...thats all i can say

 

[jasonLee]

ok...IT DID somehow just pop back on....go figure it felt good ....i was nervous.....so now i will blow out all the tubes that supply water and put it back together....THANKS

 

[jasonLee]

having issues.....i think maybe I should have put it in reverse before I tore it apart??....one video said the splines might not match up so spin the prop till they do......
so I twisted on the black thing that appears to be the shift mechanism in the first pic and now its either in reverse or forward .....I am not sure which...but the shaft spins when i spin the prop ......if I can get stuff lined up I can ratchet it back slowly...hope i didnt screw up by moving the shifter.....

 

[racerone]

Classic situation.----Has happened thousands of times.-----The clutch dog is spring loaded.-----If you remove L/U in neutral it often jumps into forward.-----So drop the L / U and put it in neutral.----Re-assemble.-----Or both in reverse and re-assemble.----Or both in forward and re-assemble.----Done.

 

[jasonLee]

so i have gotten the spline lined up ...and its in neutral.....and get within about 5/8's of an inch and then the shifter rod from above misses the clutch dog because the rod wiggles around .....if you put it in reverse or forward the clutch dog can also wiggle around but I dont think that will help...so I got it neutral because the clutch dog dont move.....some how i need to wiggle that rod from above ....I am positive everything else is lining up.....you can see where the grease rubbed off on the spline and see its going in 3/4 of an inch.....so its the shifter rod causing my pain....

 

[jasonLee]

got the rod to hold still .....and lined up .....and then she all went back like it was,.,.not sure why there aint no videos about the shift shaft ....maybe I suck at googling ......no prob....I fingered it out and now she pee's like a drunk man.....see ya in another 5 years!!