Notorious 470 coolant leak

[dn010]

So I just got done replacing my bellows, gimbal bearing, shift cable, rebuilt upper drive unit, new u-joints the whole 9 yards. Anxious to get the boat in the water next weekend right? Hah!

You "470" club folks can add me to your list of those who have bad front camshaft seals allowing coolant to leak through the weep hole. Noticed coolant dripping from the drain hole in my boat so I went to investigate and saw the sad sight of a dripping weep hole. My engine is from '78; I haven't taken it apart yet but I can guarantee that my camshaft is probably rusted where the seal is since the boat sat for a long time.

My question is where can I find the sleeves to install on the camshaft? Where can I find seals? Tried searching around a little bit and didn't find much. I'm off to tear it apart... Thanks guys in advance for any help!

 

[proshadetree]

Re: Notorious 470 coolant leak

http://www.breezeworks.net/cgi-bin/MBoard/forum/display_forum_topics.asp?ForumID=1&PagePosition=2

Might look here, lots of fans of these motors I tend to run from them

 

[stonyloam]

Re: Notorious 470 coolant leak

Do a search here for "Speedie Sleeves" there are a bunch of threads. Your Mercruiser dealer will have the seals and gaskets. You might want to pull the cover and look at the cam. If if is not grooved, you may not need the sleeves.

 

[zbnutcase]

Re: Notorious 470 coolant leak

I get 'em at my local bearing store, and yes, you will need one

 

[stonyloam]

Re: Notorious 470 coolant leak

One little note here: The garter spring (open side) of both seals face forward toward the coolant when you install them. Object is to keep coolant out of the crankcase. That question comes up a lot LOL. Good luck, and welcome to the club!

 

[stonyloam]

Re: Notorious 470 coolant leak

Just trying to think of some other random stuff here:

You can substitute NAPA (Permatex) Aveation sealant for Perfect seal.

You can borrow a harmonic balancer puller/installer from Autozone for free, puller works fine, but you need to add a spacer to get the installer to work, a 1/2 inch drive socket of the right size should do it. Do not try to drive it on, you can knock the magnets loose. The center bolt is 1/2 inch fine thread, you can also use a longer bolt and some greased washers to install it, the stock bolt is too short and can strip out.

Be very careful with the torque of the cover bolts, cover is aluminum and can crack if not very careful (don't ask me how I know).

The pan gasket is outrageously expensive, so if you mess it up when taking the cover off, just use some gasket material, and use the cover for a pattern to make a new front section.

Plan on replacing the crankshaft seal when you do the cam seals.

This is a pretty good article on how to do it http://www.sterndrives.com/470information/470coolantleakrepair.html You should not have to mess with the motor mount.

While you are in there take a good look at the timing chain and tensioner, to make sure they are OK.

All I can think of for now. Lots of guys here to help. Good luck.

 

[dn010]

Re: Notorious 470 coolant leak

Thanks guys for your posts - you've all been most helpful! I am looking for the parts right now and will be starting the dis-assembly shortly. I started the engine to let it run for a little just because I'm not sure when I'll be done fixing this... I notice that the pump only leaks when the engine isn't running; but doesn't when it is running regardless of just being started or running at operating temp... It's a shame! I think I'm going to pull the head off and change the gasket while I'm doing all this. Why not, right? Thanks again!

 

[telstar1]

Re: Notorious 470 coolant leak

Myself Id do the seal then see how it goes. If no coolant loss, head gasket is good IMO. Could do a retorque on head. (a must if you do change H.G.)

 

[stonyloam]

Re: Notorious 470 coolant leak

If you do the head gasket it is best to replace it with a OEM Mercruiser gasket, As I understand it it is designed specifically for the 470 and is less prone to failure then the aftermarket ones. The other gaskets (valve cover ect), aftermarket should be fine. It is very important that you follow the instillation instructions in the manual, including retorquing after initial warm up. While you have it off it might also be a good time for a valve job and instillation of hardened exhaust seats. Make sure that the pushrods go back in the same holes they came out of. Pay close attention to the tightening sequence for the head and the rocker arms. I am probably telling you things you already know, but it is easy to get in trouble with the 470, don't I know it LOL

 

[dn010]

Re: Notorious 470 coolant leak

Well, I figured since I drained the coolant and took the stuff off of the front of the head I may as well change the gasket since it is 32 years old. I got the camshaft hanging out now so I just need to figure out which speedie sleeves and seals I need and then I'm back in business. The camshaft has a pretty nasty groove so I can't get away without needing the sleeves. Do I still use the OEM seals with the sleeves?

 

[telstar1]

Re: Notorious 470 coolant leak

32 years wow thats good,I guess you are in the 470s are good club?I love em, unfortunately sold the boat I had one in. I did use a truck 460 head gasket, had no issues and way cheaper.Stonyloam you might have something there about oem I dont know. To me thetruck one looked and worked fine.

 

[stonyloam]

Re: Notorious 470 coolant leak

This is a note that I got from VIC1 a while back when he did his:

"We used a sleeve of 0.870 as measured with the micrometer and purchased 2 just in case something happen to the first one. We used both of them together to make sure we covered the entire area the shaft was worn. Since there was a little play on one of the sleeves the locktite (#620) held in place well."

You will have to measure with a micrometer to be sure, but it should be somewhere around there. You will need two sleeves, 1 is not wide enough. Yes you use OEM seals.

 

[dn010]

Re: Notorious 470 coolant leak

Thanks for your posts; I have most of the parts on the way. I was looking at the speedi sleeve gold version for this repair but it is just way too expensive; so I'm going with standard.

I haven't gotten the cam seals yet but soon. Are these seals the same as the water pump seals in the drive?? I am getting mixed reports that it was superseded by # 26-33144 and is the same thing as what I have in the outdrive... Is this true? The other 89238 seals look "flat" like the old seal without sealing lips; I'd prefer to get a newer style seal with 2 lips...

 

[whatsagm]

Re: Notorious 470 coolant leak

I don't know if this helps, but when i bought my boat the 470 had a cracked cylinder. I got a new block punched it 30 over redid all of it. I had my machine shop grind down the cam and re weld it with a silicone material. Basically the seals will never eat into the metal again. I love my 470 but i also have done all the up grades to it. The only thing left to do is go with the aluminum head.

 

[stonyloam]

Re: Notorious 470 coolant leak

I don't know, it may be used in both places. Here is the parts breakdown for your engine (76-79, 4208730-5520114): http://www.mercruiserparts.com/Show...inbr=1592&bnbr=120&bdesc=FRONT+COVER+ASSEMBLY It might be worthwhile to contact your local Mercruiser dealer. Good luck.