1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

[osborne looney]

New to 470's have had a few inline 4cyls before but not like this !!! bought it real cheap -- last owner said water pump was leaking thru weep hole ? but from what i am finding there is no weep hole ? correct me if i am wrong .
can impeller be replaced ? or does cam have to be pulled ? once again i show my ignorance in 470's any help would be great thanks

SER# on rocker cover A679772 is coming up as NO GOOD ?

the more research i do i am finding that just maybe it is a 1986 engine put in a early 87 boat ?

 

[Eric 3.7LX Alpha 1]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Oh my boy there is a weep hole and you have a nice weekend project ahead of yourself...

The engine circulating pump is 99% never the issue. You have a seawater pump in the drive that must be religiously maintained as well as your temperature gauge.. if these engines overheat... it's a new head gasket for you.

Here... read this article on the job:
Mercruiser 470 Coolant Leak

here is a picture of the weep hole:


The plus is you have fresh water cooled, and your block will never crack from not winterizing early enough. In fact winterizing a 470 is a snap, and they have tons of torque with their huge engine bore, sip gas compared to the others, and are lighter since the block is Aluminum and not cast iron....

There are several Mercruiser Mechanics with high ranking on here...
and many of us 470 owners so if you have any questions ask away... and welcome to the
470 club:facepalm: :facepalm:

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

long story short -- i actually replaced the head gasket last fall for the guy i bought the boat from, he never fired it up after that !!!!! now my gut tells me he OVERHEATED it to begin with because of weep hole seeping massivly !!!! `i am a darn good wrench i own a small engine & tire repair shop so hopefully it wont be that much of a mess thanks so much for the pic -- it will help out greatly ,
i assume the whole front cover has to come off ? thanks again

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Oh my boy there is a weep hole and you have a nice weekend project ahead of yourself...

The engine circulating pump is 99% never the issue. You have a seawater pump in the drive that must be religiously maintained as well as your temperature gauge.. if these engines overheat... it's a new head gasket for you.

Here... read this article on the job:
Mercruiser 470 Coolant Leak

here is a picture of the weep hole:
View attachment 203881

The plus is you have fresh water cooled, and your block will never crack from not winterizing early enough. In fact winterizing a 470 is a snap, and they have tons of torque with their huge engine bore, sip gas compared to the others, and are lighter since the block is Aluminum and not cast iron....

There are several Mercruiser Mechanics with high ranking on here...
and many of us 470 owners so if you have any questions ask away... and welcome to the
470 club:facepalm: :facepalm:

one more dumb question on this setup what would cause weep hole to leak ?

 

[wrestling coach]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Weep hole leaks antifreeze because the cam seals are failing and/or grooves have been worn in the cam snout by those cam seals. Usually repaired by installing speedi sleeves on the cam snout and new cam seals in the cover.

Dennis

 

[stonyloam]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

On the 470 the engine waterpump the impeller is bolted directly to the end of the camshaft. To keep coolant from leaking out and into the crankcase there are two seals in the timing chain cover that ride on the cam. The seals are spaced a little bit apart. The weep hole is located in the space between the two seals, so that when coolant (under pressure) is forced past the front (worn) seal it leaks into the space and out of the weep hole, and since it is under essentially no pressure the second seal keeps it out of the crankcase. So unless a tremendous amount of coolant loss there would be little effect on the cooling capacity from leaking coolant out of the weep hole. Not a bad job to replace. If you have room to get a puller on the rotor you will not have to mess with the motor mounts, and no expensive tools are needed. here is the area you are looking at: http://www.mercruiserparts.com/Show...39469.png&inbr=908&bnbr=170&bdesc=FRONT+COVER #2 are the seals. Here is your engine manual: Boatinfo - Mercruiser Service Manual nr. 8 - 1985-1989 - Mercury Marine 4 Cylinder Engines Good luck and welcome to the "470 Club" :facepalm:

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

On the 470 the engine waterpump the impeller is bolted directly to the end of the camshaft. To keep coolant from leaking out and into the crankcase there are two seals in the timing chain cover that ride on the cam. The seals are spaced a little bit apart. The weep hole is located in the space between the two seals, so that when coolant (under pressure) is forced past the front (worn) seal it leaks into the space and out of the weep hole, and since it is under essentially no pressure the second seal keeps it out of the crankcase. So unless a tremendous amount of coolant loss there would be little effect on the cooling capacity from leaking coolant out of the weep hole. Not a bad job to replace. If you have room to get a puller on the rotor you will not have to mess with the motor mounts, and no expensive tools are needed. here is the area you are looking at: http://www.mercruiserparts.com/Show...39469.png&inbr=908&bnbr=170&bdesc=FRONT+COVER #2 are the seals. Here is your engine manual: Boatinfo - Mercruiser Service Manual nr. 8 - 1985-1989 - Mercury Marine 4 Cylinder Engines Good luck and welcome to the "470 Club" :facepalm:

THANK YOU so much for the info -- it shouldn't be too much of a struggle --except for removing the back seat to get the clearance i need and make it a lil easier on this old fart --thanks again

 

[stonyloam]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

One thing about the job: I used a harmonic balancer /installer kit borrowed from autozone to remove my rotor (on the 470 it is a rotor rather than a harmonic ballancer) from the crankshaft. Pulling the rotor was easy, however reinstalling it was more of a problem because the rotor is too deep for the installer to work. I got it to work by using a piece of pipe as a spacer, but don't remember exactly how:facepalm:. You can make an installer by using a length of 1/2 inch fine threaded rod and a stack of greased washers and a nut. Grind a couple of flats on the end of the rod for a wrench, run the nut up the rod and add washers (or pipe spacer), screw the rod into the end of the crank and tighten the nut against the washers to pull the rotor back on. You do not want to drive the rotor on, because tapping on the rotor can disloge the magnets glued inside. have fun. BTW when you get it running right the 470 is a really nice powerful engine.

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

One thing about the job: I used a harmonic balancer /installer kit borrowed from autozone to remove my rotor (on the 470 it is a rotor rather than a harmonic ballancer) from the crankshaft. Pulling the rotor was easy, however reinstalling it was more of a problem because the rotor is too deep for the installer to work. I got it to work by using a piece of pipe as a spacer, but don't remember exactly how:facepalm:. You can make an installer by using a length of 1/2 inch fine threaded rod and a stack of greased washers and a nut. Grind a couple of flats on the end of the rod for a wrench, run the nut up the rod and add washers (or pipe spacer), screw the rod into the end of the crank and tighten the nut against the washers to pull the rotor back on. You do not want to drive the rotor on, because tapping on the rotor can disloge the magnets glued inside. have fun. BTW when you get it running right the 470 is a really nice powerful engine.

Thank you -- i have a few types of pullers screw and jaw type i am going to start on it this morning -- i have to remove back bench seat on a 87 winner -- now that is is a little cooler up here should be ok thanks for the info

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

After pulling seat-and front cover which went pretty smooth i found someone before me PLUGGED weep hole with silicone and a screw !!!! how stupid can a person be.
Did some research found cam seals C/R = 8700 and national seal # 471570 taking 1 day from local carquest .
cam has little or NO WEAR or grooves which is surprising to me it will clean up nicely . thanks for all the info on the 470

 

[stonyloam]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

After pulling seat-and front cover which went pretty smooth i found someone before me PLUGGED weep hole with silicone and a screw !!!! how stupid can a person be.

Yeah that is the WORST thing you can do. With the hole plugged there is no place for leaked coolant to go except into the crankcase. All 470 owners should check to make sure that weep hole is clear. You will want to do the crankshaft oil seal too. Remember both cam seals face out to keep the coolant out of the crankcase (garter springs face away from the block) and the oil seal faces the block. It is easy to get confused LOL. My cam was in about the same condition and I did not use spedi sleeves and it has been holding for ten years. Good luck.

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Thanks
i marked cover before removing seals on which way springs were facing (too many years of hard knock schooling ) oil seal is being replaced as well as oil and filter - even the pan gasket stayed intact during removal but i will add a lil silicone for added coverage .
Otherwise this thing ran like new for the minute i did run it before digging into it .

Again thanks for the info

Yeah that is the WORST thing you can do. With the hole plugged there is no place for leaked coolant to go except into the crankcase. All 470 owners should check to make sure that weep hole is clear. You will want to do the crankshaft oil seal too. Remember both cam seals face out to keep the coolant out of the crankcase (garter springs face away from the block) and the oil seal faces the block. It is easy to get confused LOL. My cam was in about the same condition and I did not use spedi sleeves and it has been holding for ten years. Good luck.

 

[stonyloam]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

One more thing you should probably also replace the impeller in the outdrive. Particularly critical in a 470, need to keep it cool. Have fun.

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

One more thing you should probably also replace the impeller in the outdrive. Particularly critical in a 470, need to keep it cool. Have fun.

Will be replacing that today -- while i am waiting for seals to come in

 

[stonyloam]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

One great thing about your 470, especially in WI is the ease of freeze protection. In the fall all you need to do is pull the aft plug on your heat exchanger and drain out the raw water, takes about 5 min. I do mine right on the ramp when I pull the boat for the winter. That means if you have a nice day in late fall, all you need to do is put in the plug and go boating, drain when you pull it out.

 

[BrianD1973]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Are you talking about the water pump impeller? How long can one possibly use boat while it weeps before it becomes a major issue?

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Are you talking about the water pump impeller? How long can one possibly use boat while it weeps before it becomes a major issue?

MAYBE YOU should of read from the beginning

 

[osborne looney]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

One great thing about your 470, especially in WI is the ease of freeze protection. In the fall all you need to do is pull the aft plug on your heat exchanger and drain out the raw water, takes about 5 min. I do mine right on the ramp when I pull the boat for the winter. That means if you have a nice day in late fall, all you need to do is put in the plug and go boating, drain when you pull it out.

OMG what a nightmare this tub has turned into !!!! pulled lower 1/2 to change impeller strangely enough it was new -- but when i pulled cover on upper just for a look-see the GEARS WERE TOTALY GONE -- ground smooth -- so i will be looking for a good upper now aaarrrgghhh i am pretty sure it is a 1.84 ratio -- hopefully this is all -- gear lube would of been great at some point a real LACK of maintaining on this one

 

[BrianD1973]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Ha, did read from the beginning... but as a newbie trying to work on my parent's older boat I just wasn't familiar with an impeller in the OUTDRIVE... to me the outdrive is the lower drive unit of the boat? Didn't know if I was missing something and therefore your assumption that I didn't read the whole post is incorrect.... I'm more familiar with vehicle engines therefore the question of impeller in the water pump I will have to find a schematic to see where this impeller is in the outdrive... the topic was about a water pump... sorry for all the confusion but I guess as a newbie I'm retarded to some

 

[Eric 3.7LX Alpha 1]

Re: 1987 mercruiser 470-170hp water pump replace ? maybe 1986 eng in 87 boat

Sorry to hear about the gears in the upper unit.



The impeller is in the lower half of the outdrive,


Here's a video Achris made for your viewing pleasure