Another 470 Leaking Coolant

[SDSeville]

Re: Another 470 Leaking Coolant

Thanks for the advice guys. However, I was not able to salvage the oil pan gasket. I tried and tried and even broke a razor knife in the process, but the gasket pulled right off with the timing cover. Even though all my razor work was on the top of the gasket, it pulled cleanly of the pan instead of the cover.


When I pulled the timing cover, I found that someone had replaced the seals before. However, instead of using speedi sleeves, it looks like they used 2 gaskets in order to change where the seals ride.


Some nice scratches in the timing cover from when the PO replaced the seals. The seals aren't even in there straight. This one is only bottomed out on one side and sits about 1/8 to 1/16" off on the other.

 

[SDSeville]

Re: Another 470 Leaking Coolant



There are some nice grooves and rust on the camshaft. Per the directions, I will measure the camshaft near the timing sprocket where the shaft is still in good shape.

Measured - .8725"

 

[SDSeville]

Re: Another 470 Leaking Coolant

I just went to the SKF site and it looks like they don't have anything for .8725. They do have sleeves for .873. Is mine close enough to use these?

 

[stonyloam]

Re: Another 470 Leaking Coolant

The gasket should be no big deal. Like was said before, take a razor blade and trim the gasket on the pan flush with the edge of the block, then find sheet gasket material (of the right thickness) and using the bottom of the cover for a template cut a new section. The only critical points are the two corners, and a little extra sealant should take care of that.

 

[SDSeville]

Re: Another 470 Leaking Coolant

The gasket should be no big deal. Like was said before, take a razor blade and trim the gasket on the pan flush with the edge of the block, then find sheet gasket material (of the right thickness) and using the bottom of the cover for a template cut a new section. The only critical points are the two corners, and a little extra sealant should take care of that.

Thanks Terry. Dumb question -- how do I know the right thickness? the piece I have (and can see on the sides) is compressed.

Also, I saw your post on jabfd's thread about the sleeves. Should I just go with the slightly bigger size? ...and that post you quoted said he used 4 sleeves? I thought we were supposed to use 2?

 

[stonyloam]

Re: Another 470 Leaking Coolant

Your auto parts dealer or your local Mercruiser dealer should be able to help. Ideally the sleeve should be tight enough that it will stay in place when driven on, but if it is loose they recommend loctite. Yeah 2 should do it.

 

[ericcarr2000]

Re: Another 470 Leaking Coolant

Don't worry too much about that bottom oil pan gasket. Just make sure you get the correct thickness gasket material and make one of your own, or you could just order a new gasket and cut off the piece you need and put a bit of gasket making material, RTV, on it so it will swell a tad bit when torqued down. I've had to do this a few times and didn't have any problems with it leaking at all.

 

[stonyloam]

Re: Another 470 Leaking Coolant

Yeah, except the OEM gasket is about $80 and the "cheap" aftermarket is about $30 :facepalm:

 

[SDSeville]

Re: Another 470 Leaking Coolant

I guess I can bring my caliper down to the shop and measure the thickness of the oem gasket then just buy a piece of the gasket material with the same thickness.

 

[SDSeville]

Re: Another 470 Leaking Coolant

OK, the parts are all in. I will give the speedi-sleeves a shot tomorrow. The Stern Drive directions seem so simple -- center each sleeve over the grooves that have worn in the cam shaft. If it is that easy, why do we see people with torn and leaky seals having to do this job a second time?

Any special tips here?

 

[SDSeville]

Re: Another 470 Leaking Coolant

I will be installing the speedi-sleeves today. Upon further inspection, there is only a groove where the front seal was. There are some visible marks where the rear seal was, but it is totally smooth.

Do I need to install a sleeve for the rear seal?

 

[stonyloam]

Re: Another 470 Leaking Coolant

The seals are independent from each other, so if you don't think it is necessary, you don't have to install both sleeves.

 

[SDSeville]

Re: Another 470 Leaking Coolant

Thanks Terry. Is this unusual that one seal wears a groove and the other doesn't?

 

[stonyloam]

Re: Another 470 Leaking Coolant

Well the front seal sees pressure from the coolant, so that could cause the front seal to press harder on the cam surface making more of a groove. Just speculation on that one.

 

[SDSeville]

Re: Another 470 Leaking Coolant

Well the front seal sees pressure from the coolant, so that could cause the front seal to press harder on the cam surface making more of a groove. Just speculation on that one.

That makes sense...and maybe having oil on one side helps the rear seal too?

So if I am going to pass on the rear speedi-sleeve, what should I use to clean up that area? and the middle part that is rusty?

 

[stonyloam]

Re: Another 470 Leaking Coolant

I would do a google search for "hand polishing a crankshaft" and see what they suggest. For the rusted area, I would just tape over the polished area and hit it with a Scotchbrite pad to knock the loose stuff off.

 

[SDSeville]

Re: Another 470 Leaking Coolant

I would do a google search for "hand polishing a crankshaft" and see what they suggest. For the rusted area, I would just tape over the polished area and hit it with a Scotchbrite pad to knock the loose stuff off.

Ooops. I used 1200 sand paper to get the rust off and did not tape. It didn't take much sanding to get it to look great and I was careful about the area where the back seal will go. Could I have sanded too much off the shaft?

 

[stonyloam]

Re: Another 470 Leaking Coolant

Nah, should be fine.

 

[SDSeville]

Re: Another 470 Leaking Coolant

Installed the seals first so I can get good measurements for the speedi-sleeves.

Back seal. The scratches and chips are from when PO did this repair (obviously not correctly).


Front seal. I installed this one flush per directions. PO had it installed about 1/8" in from flush. I guess he was trying to get it ride somewhere besides the nice groove that is worn.


To support the cover during the hammering, I cut different sized pieces of 2" PVC.

 

[SDSeville]

Re: Another 470 Leaking Coolant

I measured between the seals and it is 9/16" from center to center. Since there is no groove where the rear seal was, I plan to center the rear sleeve 9/16" back from the front groove.

Couple questions before proceeding.

1. Do I need to remove the the flange from the rear sleeve? I saw a video where the guy left it on.
2. Should I fill the front groove with JB weld before installing the sleeve?