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mercruiser 470 circ pump leak

On the Merc 470/3.7L engine, the forward area of the camshaft drives the coolant circulating pump impeller.
(not the crankshaft as another member has mentioned in a similar thread)
The inner cover (i.e., timing chain cover) in this area requires special sealing between the oil side and the coolant circulating pump impeller side.
(I have repaired these over the years. this has been a problematic area on this engine since it's birth)

The front covers are also known to have issues with regard to warping.

To correct this, you will need to remove both front covers and and replace the seals.



 Merc 470 cam and circ pump impeller drive.jpg

You will want to inspect the seal surface as well.


.
 
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Refer to this link from this web site

http://www.marineengine.com/parts/m...il4-19831984/6218037-thru-6916778/front-cover

Both seals need to be replaced to fix coolant leak.

Seal lips on both face liquid side of cover in other words out towards front of engine.

This repair I have actually done many times. Unlike Mr Moron who has never touched a Mercruiser 470.

Mercrusier recommends pulling the entire front cover and also replacing the crankshaft seal.

If it were me, I would do so............

Also make sure to look at shaft where seals ride. You may need to clean/lightly sand shafts to get a clean sealing surface. (if so care must be used so you dont remove to much material).

Attached two images are directly from MY PERSONAL Mercruiser Manual (which that moron does not possess)

Not sure where he got his image but as you can see it has been edited..............most likely incorrectly.


If you are unable to perform this then seek out someone who can.
 

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  • Mercruiser manual-470 water circulation seal replacement image 1.jpg
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  • Mercruiser manual-470 water circulation seal replacement image 2.jpg
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Attached two images are directly from MY PERSONAL Mercruiser Manual (which that moron does not possess)

Not sure where he got his image but as you can see it has been edited.............. most likely incorrectly.
Click to expand...

Other than the notations that someone had added, perhaps someone can point out where these two images differentiate and perhaps how that would make any difference for the purpose of explaining the position and location of these seals.


Merc 470 front cover images.jpg
 
RicardoMarine said:
Other than the notations that someone had added, perhaps someone can point out where these two images differentiate and perhaps how that would make any difference for the purpose of explaining the position and location of these seals.


View attachment 20623
Click to expand...

Problem is exactly what you said.......

SOMEONE EDITED THE IMAGE.....SO YOU COPIED IT FROM SOME OTHER UNKNOWN SOURCE AND NOT YOUR OWN AND NOT FROM AN ACTAUAL MANAUAL.

THATS THE PROBLEM!!.
 
kghost said:
Problem is exactly what you said.......

SOMEONE EDITED THE IMAGE.....SO YOU COPIED IT FROM SOME OTHER UNKNOWN SOURCE AND NOT YOUR OWN AND NOT FROM AN ACTAUAL MANAUAL.

THATS THE PROBLEM!!.
Click to expand...

Jack, please note that I did not refer to this as a Problem.
I asked if someone could point out where these two images differentiate in a way that could make any difference regarding the purpose of explaining the position and location of the seals.
Perhaps read it again!

I know that you are proud of your Personal Mercruiser manual ownership, and that's fine! I am glad that you can refer to them!
Perhaps elaborate as to why it's so important that we (the members) post images that were taken from our own personal manuals?
If an image that was copied happens to be the exact same image found in the manual, then how does this de-value anything?


Lastly, please find a way to not be threatened by another member's post!
As said multiple times now..... if you disagree with a member, simply state so, and then go on to explain why, and do so politely and adult like.

There is a small group of us here who are concerned about your attitude, and quite frankly we are very tired of it!




 
I
RicardoMarine said:
On the Merc 470/3.7L engine, the forward area of the camshaft drives the coolant circulating pump impeller.
(not the crankshaft as another member has mentioned in a similar thread)
The inner cover (i.e., timing chain cover) in this area requires special sealing between the oil side and the coolant circulating pump impeller side.
(I have repaired these over the years. this has been a problematic area on this engine since it's birth)

The front covers are also known to have issues with regard to warping.

To correct this, you will need to remove both front covers and and replace the seals.



View attachment 20544

You will want to inspect the seal surface as well.


.
Click to expand...
so is this a serious problem or can the seals be replaced whitout any other problems?
 
draco1800swiss said:
Ok but i cant be that water rush trough this seals into the motorblock?
Click to expand...
not into the block but into the crank case and oil, yes this is possible if both seals are leaking. There are two back to back seals with a weep hole in between. One seal on water pump keeps the coolant in the water side, other seal on crankcase side keep oil in. the weep hole in between should keep coolant from getting in oil but doesn't always. big issue is cam gets groove worn so you need to put a sleeve over the cam nose not just do the seals

in the end the 470/3.7 was a relatively trouble prone engine, there is a reason mercruiser dropped it from its offering 30 plus years ago
 
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