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replacing waterpump impella and its v belt problems.

I'm new to this site and my boat (bought end of last season)
she is bocked up in my yard.
was ready to launch (i thoght) but when i tried to start engine with muffs, water wouldnt flow through
figured it was impella so i tried to replace it. took a while but finally got housing off.
when I tried to reinstall i could not get more than 1 of the 5 screws in at a time.
then I figured maybe i should have lossened the v belt first.
Stud on the idle pully did not have a hex like video showed. loosened the larger nut but idler didnt move.
Stupidly i pried the belt off and was finally (with great difficulty and many tries) to get the screws back in the pumpo housing.
Now i cant get the belt back on. after researching i am now convinced that the pulley stud should have had a hex to loosen it. But close up pictures i took with my camera show no sign of a hex. looks round and smooth so i guess someone had tried to use vice grips to loosen even though it looks smooth.
I have orderd a new pinion stud, pulley, and v belt. I am also going to order a water pump kit (body, bolts, o ring .wear plate) because i was cheaping out before to try and rush the job.

So here are some questions:
1. should i have been able to this without loosening / removing the v belt (looked easy on yiou tube but i just could line up to ut in the screws.

2. confirm that there should have been a hex on the pulley stud and that the nut only keeps it locked in
Also there was a cerclip o]n the stud is this just so you dont loosen the nut to much?

3. Here is the big one. Am i going to be able to replace the pulley by just unscrewing the rstud retaining nut. that is , once i remove pulley and bushing will i be able to remove the stud or do i have to also reve the mounting braket and how hard is that. there is not much room in front of the engine and all this would probably have to be done one handed. I am fairly mechanical (infact I am retired mech engineer) but I am not that agile.

4. Also, all the pump kits seem to have two shorter screws besides the 5 I need, what are they for?

Any and all tips will be greatly appreciated (i will try to adda picture of the pulley and stud once i figure out how.

Thanks







1
 
You can remove the pulley. There's a toothed gear on the bolt that engages on a rack on the bracket. By loosening the locknut and rotating the pulley bolt it raises/lowers the pulley to adjust the belt. You might want to pull all that apart and have a look to be sure it's free of rust as it's just plain steel. Just take the locknut all the way off and push the bolt out. The pump kit contains bolts for both the one-piece and the two-piece housing, which is why there are extra. When reassembling, I use a very very light coating of vaseline to help the impeller back in the housing. Always keep a spare pump impeller on board in your kit, along with belts and stuff.
 
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there are no adjusters with V belts?
If this is a Bravo pump, yopu remove the pump with its bracket by removing the adjuster bolt, 2 mounting nuts, 2 hoses.
Manual 15 indicates an adjuster is only used with the cooling pump/fuel pump type
 
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You can remove the pulley. There's a toothed gear on the bolt that engages on a rack on the bracket. By loosening the locknut and rotating the pulley bolt it raises/lowers the pulley to adjust the belt. You might want to pull all that apart and have a look to be sure it's free of rust as it's just plain steel. Just take the locknut all the way off and push the bolt out. The pump kit contains bolts for both the one-piece and the two-piece housing, which is why there are extra. When reassembling, I use a very very light coating of vaseline to help the impeller back in the housing. Always keep a spare pump impeller on board in your kit, along with belts and stuff.
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I messed up trying to reply to this at first (=and couldnt figure out how to deletre it see next reply.
 
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You can remove the pulley. There's a toothed gear on the bolt that engages on a rack on the bracket. By loosening the locknut and rotating the pulley bolt it raises/lowers the pulley to adjust the belt. You might want to pull all that apart and have a look to be sure it's free of rust as it's just plain steel. Just take the locknut all the way off and push the bolt out. The pump kit contains bolts for both the one-piece and the two-piece housing, which is why there are extra. When reassembling, I use a very very light coating of vaseline to help the impeller back in the housing. Always keep a spare pump impeller on board in your kit, along with belts and stuff.

I think I am starting to undestand.  I think what you are calling the bolt that engages a rack on the bracket is the "stud", Part #30 in the diagram at ;
http://www.marineengine.com/parts/mercury_marine_parts/sn/0D832972/474B110FS/1621_330 I couldnt understand before how rotating it could adjust the pulley, but i think i do now. This is the stud that i think is suppose to have a hex on the end but mine is rounded off. I think I will understand better when the part comes in. But from what i can tell i wont be able to replace the bolt/stud with the gear without removing the bracket with the slot/rack. looks like it is might held by two bolts (27&29). I'm not sure i have the room or hand agility to do this. I've already sprayed the area with pt blaster - i am tempted to put a vice grip on the stud and try to rotate. cant do any more damage.
 
You can remove the pulley. There's a toothed gear on the bolt that engages on a rack on the bracket. By loosening the locknut and rotating the pulley bolt it raises/lowers the pulley to adjust the belt. You might want to pull all that apart and have a look to be sure it's free of rust as it's just plain steel. Just take the locknut all the way off and push the bolt out. The pump kit contains bolts for both the one-piece and the two-piece housing, which is why there are extra. When reassembling, I use a very very light coating of vaseline to help the impeller back in the housing. Always keep a spare pump impeller on board in your kit, along with belts and stuff.
I amstill struggling with this , I was away. I have a new pinion stud (P/n 30 with the gear on the end of it) I almost have the lock nut all the way off the old one but there is no siogn that it can move once i get the nut off i may try tapping with a hammer. I'm still not suer if i can get the new stud in without removing bracket and im not sure if i can remove the bracket. Some one below (bt doctor) says there is no adjuster on the v belt and that i have to remove the whole pump (and fuel pump??) and bracket i've yet to see a good diagram of the pump, fuel pump and pulley bracket and how they all fit together. I'm afraid i may be trying to get this stud loose and i dont actuall have what shown in the diagram. any and all help and suggestions welcomed.
 
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I amstill struggling with this , I was away. I have a new pinion stud (P/n 30 with the gear on the end of it) I almost have the lock nut all the way off the old one but there is no siogn that it can move once i get the nut off i may try tapping with a hammer. I'm still not suer if i can get the new stud in without removing bracket and im not sure if i can remove the bracket. Some one below (bt doctor) says there is no adjuster on the v belt and that i have to remove the whole pump (and fuel pump??) and bracket i've yet to see a good diagram of the pump, fuel pump and pulley bracket and how they all fit together. I'm afraid i may be trying to get this stud loose and i dont actuall have what shown in the diagram. any and all help and suggestions welcomed.
So i got the lock nut all the way off and tried to pull off the pulley. even tried prying with a large screwdriver. didnt want to try to hard in case i'm missing something. Srtange thing is I tried to threading old locknut on to the new stud and it doesnt quite fit. like mabe one is metric or wrong pitch. So maybe my set up doesnt use this kind of geared stud. I stilll cant see enough to see what going on. and if i would be ablke to take off the poulley bracket. There is one large engine block water hose blocking my view and it wont come off easy and im not sure how hard i want to try . it would be difficult to put back on. I have some pics but havn't taken the time to learn how to post them.
 
there are no adjusters with V belts?
If this is a Bravo pump, yopu remove the pump with its bracket by removing the adjuster bolt, 2 mounting nuts, 2 hoses.
Manual 15 indicates an adjuster is only used with the cooling pump/fuel pump type
what adjuster bolt, what two mounting nuts.. my pump sems to be integral with the fuel pump. are you taliking about removing both together. you may be describing a diff setup then me that uses the two shorter bolts that came with the kit .
 
and tried to pull off the pulley. even tried prying with a large screwdriver. didnt want to try to hard in case i'm missing something.

Ayuh,...... You must use the proper puller,.....
 
let me start over with some basic questions. This is for a 1992 7.4 bravo gen V

1. should i have taken v belt off idler pulley to replace replace water pump impella and housing? That is, should i have been able to do it without toching the belt.

2 Should i be able to remove the old water pump idler pulley stud (geared pinion) and install my new pinion without removing the bracket it is mounted to.

3. if i do have to remove the bracket, does any one have a good picture / diagram of the bracket and mounting bolts other than the standard parts diagream ( http://www.marineengine.com/parts/mercury_marine_parts/sn/0D832972/474B110FS/1621_330 )

4. Any suggestions for getting the old pully and bushing off the stud. I only have about 4 " in front of the pulley so i dont think i can use a gear puller. I dont want to try any too drastic until i'm sure i will be able to install my new pinion.
 
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NEVER need to take the pulley off to replace the impeller!!!


1)Remove belt after loosening adjuster on idler pulley.

2)Disconnect fuel and water lines ( make note, i.e. MARK THEM where the water lines go!!! on the pump)

3)and then remove the whole assembly ( water pump, fuel pump, cast iron bracket) from the engine.... typically just two bolts.

4) Remove all bolts thru plastic housing and pull off the the pump housing... ( take good photos before dismantling!!!)

5) IF there is any internal scoring of the plastic housing, replace housing and the S/S "wear plate" along with the impeller.

Get an OEM engine manual... can usually download for free somewhere...
 
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Thanks Cap Bob

Sounds about the way I was heading but wasnt sure if i really needed to take off the fuel pump.
The ONLY reason i need to remove the pully is that my adjuster (aka stud ,aka pinion with gear) is frozen (rusted) in place plus the 5/16 adjustment hex had been rounded off and i couldnt loosen the belt so I pushed the belt off the idler and cant get it back on. I'v PTtblasted it and tried vice grips on the rounded part but still it would not budge.


Where do you disconnect the fule lines? at the filter?

I had already replaced the impella but not the housing and wear plate but have since bought them and once i figure out what im doing will do impella and housing.
 
Easiest fo disco fuel lines at the pump itself... REmove whole assembly... Issues with the pulley/lock easier to deal with on a work bench...
 
.....and while you are at it, replace the oil in the water/fuel pump housing. It takes "gear oil" i.e., SAE 90. Inspect old oil for contamination.
 
Thanks for the oil tip Capt

I now have the seaway and fuel pump assembly out of the boat. I started removing the bracket they were mounted to (item 25 in https://www.perfprotech.com/mercury-marine-parts-catalog/sea-water-pump/assembly/1621/330?model=14 ) the nut (36) and bolt (39) are prob the “typically 2 nuts” you mentioned in your step 2. However, on mine the pully bracket (26) is also bolted to the bracket (25) with two bolts. These are pretty much seized up on mine. I Didnt want to put two much torque on them for fear of deforming the pully bracket. But I was able to remove the water/fuel pump assembly by removing 4 of the 5 bolts that mount the water pump housing to the bracket. With this and the large a large water hose (thermostat to the block) out of the way. So can finally see and get at the back of the pully bracket(26) and if i can ever get the pully and bushing off I should be able to get the pinion stud out from the back and put in the new one.

Does anyone have any suggestion of how to remove the pully bushing and stud (items 32,31,30) I have the new pully , bushing and stud and the assemble easy without interference so I wouldn’t think it would be that hard.
Bondo suggested I use the correct puller. But what is the correct puller? There isn’t room for a standard gear puller. (4 inches in front of pully) I did see a kit on line for a mercruiser pulley puller/installer but I don’t think it would work on an idler pulley.
My desperation moves might be a few wedges pobetween thevbracket and pully and maybe a hack saw to the stud between pully and bracket not sure if there is room for a blade though. Maybe I should just keep PB power blasing and trying to pry it off with screw drivers. Any thoughts??
 
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