1968 Eldorado 472 oil pan gasket and freeze plugs replacement - engine overhaul

[IcebearLars]

Regarding the chain cover, the problem is less
than adequate area to hold a gasket at the
bottom, between the chain mount casting and
bottom pan.  Just how they got the factory
gasket to work (for a while) I do not know,
probably glued it.  My advice, if there is
a gasket there, clean it out and glue the
cover directly, while you can.  Already
glued, no leak, leave it. 
...

Guess you are referring to the tranny chain cover - will have a closer look on that when the tranny moves in the row of planned work to do - currently the engine is more than full in focus   

[The Tassie Devil(le)]

I totally agree that the area at the bottom of the rear cover is really narrow, and when I saw it for myself, I was amazed.  But, with Ground Clearance in mind, I understood the reasons why.

This is one reason why I used the best Silicone Sealer that I could find that was compatible with Auto Trans Fluid.  And made sure that the mating surfaces were flat, and spotlessly clean.

I have done two transmissions with the Loctite 5900, and thus far, never a problem.

Bruce.

PS.  Don't forget that the Factory didn't use any sealer, apart from the thin Gasket when new.

 

[James Landi]

Has anyone ever heard of a chain failure?  I've not been following this thread, so simmply ignore me if that topic has been address.  Happy day, James

[TJ Hopland]

Transmission chain failure not that I know of.  I think even noticeable wear is rare and takes 100's of 1,000's of miles.  One reason is they are way over built.  4x4 transfer cases and transverse transaxles often use a similar chain to drive the front wheels and those chains are maybe 1/4-1/3 as wide.   

I think I read that the first couple years they were having the chains and sprockets made to an extremely high (and expensive) standard and rejecting a lot of them. What they ended up finding out is they could have them made to just a high standard and mixed and matched combinations of chains and sprockets to get the optimum tension.  Someone sat somewhere and found the best combinations to make a 3 piece matched set and those got sent to the assembly area or parts shelves.       

[The Tassie Devil(le)]

I read somewhere during the first year of being in the public domain, in the Oldsmobile, then the Eldorado is that they were guaranteed for life to allay some of the initial questioning.

Bruce.

[IcebearLars]

Is there a certain trick to do to get the valve stem seals bettor on the valves - they are very hard to get them on - don't want to break something.

Using this valve stem seals which came with the Fel-Pro engine gasket kit:

[The Tassie Devil(le)]

Whenever I had used Felpro Fits, and the Seals were special ones, there was an installation tool supplied with the kit.

It was a simple clear plastic sleeve, about 3/4" long, which slipped over the end of the Valve Stem.   One end was capped, and the seals simply slid over.   The sleeve was then moved to the next valve.

Bruce.

[IcebearLars]

No tool with that set of valve seals - maybe I should just make my own one from some tape or similar

[IcebearLars]

Short update on the spare smog pump to use it just as a spinning pulley w/ tightening capability of the crankshaft - water pump - smog pump belt:

Pump was seized
Got it apart and it looks like it needs new bearings
For reference here are my findings on the bearings:

Front bearing: 6203RS 17x40x12mm
Vane bearings: SCE65 (just for reference - have no need for them in the idler pulley approach)   
Rear Bearings: SCE248 or BA248ZOH

The rear bearing is just the inner part of the back drum - read in another forums that the rear bearing has a rounded/convex) face on one side and a flat face on the other side and that the rear bearing must be installed from the inside out in the support () pressing on the flat side, with the marking on the inside - guess it is easier to get the whole back ring where the bearing is in has to come out, the I will press the old bearing out and the new in (from the afterwards facing inside side) and then press the whole back of the drum again onto the drum.

Its like always - would be so nice if it would be easier

[Cadman-iac]

  Hi Lars,

Been absent for a while, and just saw your question about the crank pulley. Yes, it's steel. Make sure you have some way to get it centered when you reattach it to the rear section if you're going to try it.
Also note that the bolt pattern for the pulley and balancer is not symmetrical. It will only fit on one way.

As for your smog pump, one problem with these is in how the front bearing is fastened into the main housing. (I'm going through the one off of my 88 Suburban, which is almost identical to the Cadillac pump. It's got the outlet in the rear instead of the side. My goal is to make mine work again though).
But the bearing is retained using heated, Injected plastic, that fills a couple of grooves in the housing as well as two cut in the outer race on the bearing.
In order to get it out of the housing, you have to heat the housing until the plastic melts out, otherwise you will break the housing trying to press the bearing out.
I have searched and searched for a replacement bearing with the grooves in it, but those must be made of unobtainium. The only thing I can find is a regular 6203 bearing.
I'm considering trying to grind out two grooves in the outer race, but I'm still trying to figure out the best way to get the plastic back into the grooves.
The companies that rebuild these don't want the average person to be able to do this, obviously.

Rick

[klinebau]

Is there a certain trick to do to get the valve stem seals bettor on the valves - they are very hard to get them on - don't want to break something.

The original OEM-style valve stem seals are attached to the spring retainers for the valves.  You have to compress the spring and remove the keepers with a magnet.  Then you can replace the old retainer/seal combination with the new one.  You will need to have the heads off to do this or you need to use compressed air in the cylinder to keep the valve from dropping.  It is very easy with the correct spring compressor.

[IcebearLars]

...
Yes, it's steel.
...
Also note that the bolt pattern for the pulley and balancer is not symmetrical. It will only fit on one way.

Rick, thats fantastic information here! Would have done that for sure with a chance of 3:1 wrong by having it welded in perfect parallelism but not symmetrical to the balancer - so thanks again for that clarification and I will get the modded pulley a try if the smog pump attempt (see below) is not working gout.

As for your smog pump, one problem with these is in how the front bearing is fastened into the main housing.
...
But the bearing is retained using heated, Injected plastic, that fills a couple of grooves in the housing as well as two cut in the outer race on the bearing.
In order to get it out of the housing, you have to heat the housing until the plastic melts out, otherwise you will break the housing trying to press the bearing out.
I have searched and searched for a replacement bearing with the grooves in it, but those must be made of unobtainium. The only thing I can find is a regular 6203 bearing.
I'm considering trying to grind out two grooves in the outer race, but I'm still trying to figure out the best way to get the plastic back into the grooves.
The companies that rebuild these don't want the average person to be able to do this, obviously.

Found the thing with that plastic retainer of the bearing through my exhaustive WWW search about getting the smog pump apart as well - unfortunately too late AFTER pressing the bearing out and breaking it during that - have just checked if the housing was damaged but as it looks like in the pics I was lucky enough to not break the housing. 




   

Not sure if it not better to keep the plastic in to help the new bearing to sit tighter pressing it in. Otherwise the hint with grinding 2 grooves into the bearing housing is great and if the new bearing sits not tight enough I am thinking about getting the old plastic out and using one of this hot glue pistol to press new glue/plastic into the channels filled originally with that plastic.

Ordered a 6203 and a BA248ZOH and will keep you all posted on the results - expecting that the front bearing sits not earthquake proof with the old plastic but if it is too lose I will glue it in with above hot glue pistol , two component glue or similar. That should work for having it run as an idler pulley w/o the noise it made with the worn/seized bearings.

Cheers

Lars

[IcebearLars]

The original OEM-style valve stem seals are attached to the spring retainers for the valves.  You have to compress the spring and remove the keepers with a magnet.  Then you can replace the old retainer/seal combination with the new one.  You will need to have the heads off to do this or you need to use compressed air in the cylinder to keep the valve from dropping.  It is very easy with the correct spring compressor.

The valve stem seals look excatly as the ones which have been in (or better said the rest which remained of them) and reading your description I am thinking that I have not the right spring valve compressor tool to first compress the springs and having the rear end open (not blocked by the tool) to install the valve stem seals and afterwards the keepers before releasing pressure on the spring tool to have it sit in place all together.

My tool is from SummitRacing (SUM-906784) and looks like this and presses at the spring retainers



So either I manage to make myself this kind of sleeve which comes normally with the valve stem seal kit and press the retainer/seal combination on it and get the keepers in or I buy another tool which just compresses the spring grabbing it at the spring windings. Will work that out somehow.

[Cadman-iac]

Hi Lars,
  The glue that you are talking about using with a glue gun won't work, if you are referring to a hot glue gun. The problem is that the glue melts at too low of a temperature. The heat generated by the bearing itself plus the under hood temperature would cause the glue to melt out, releasing the bearing.
The "glue" they used is actually a nylon or plastic with nylon or other fibers infused in it for strength and heat resistance. It reminds me of the stuff used in the u-joints on some vehicles. And it takes a lot of heat to get it to melt.

Your idea of using a two part glue, or epoxy might work, but getting it into the grooves will be difficult. Being a reactive compound, you'll only have so much time before it begins to set up on you.

Now something else that I've been kicking around in my head is to use 2 or 3 set screws to clamp the bearing in place. To drill and thread the holes for a few small set screws in the housing from the front where the fan goes.
The problem with this idea is that you would have to do it before you press the shaft into the bearing, and hope that the set screws will hold the bearing in place.
  I haven't tried it yet, I'm still thinking about all the things that could go wrong with it.

The new bearing does still fit tightly in the housing on mine, but not tight enough to trust it to stay there without any additional means of retention.

Was the rear bearing bad on your pump? I've noticed that the front bearing is usually the one that goes bad. The smaller diameter of the bearing, the pressure of the belt, and the heat generated by everything tends to ruin them.
The rear bearing is twice as big, and unless it gets wet, should last much longer than the front bearing.

Getting the rear bearing out requires that the end plate be removed from the rotating housing first, then you can press the bearing out of the plate.

Another thing I'm trying to locate is the grease that they used in those bearings. Because they don't have any seals to retain it, regular wheel bearing grease will just run out when it warms up.
And because of how difficult these things are to take apart, I'd rather not have to worry about the grease dripping out.
  My pump was still working fine, it was just beginning to make noise. So I removed it before it grenaded itself. I was able to get it apart without breaking the paddles, or vanes, which ever you want to call them.
I have noticed that there are at least two different designs for the vanes from taking apart several other pumps. I was looking for extra vanes in case I did manage to break one. They aren't mix and match, so be careful if you intend to reuse them.
  I hope this helps.

Rick

[IcebearLars]

The pump I was disassembling is a spare which I got over with an spare 472 I bought back in the days. So the vanes are broken out already as well as I slaughtered everything else out of the pump. Will use it only as an idle pulley with tension capability for the belt running just the two bearings (front and rear), the shaft hub with the pulley attached - I don't even plan to get the white air blade disc on since there is no need to shovel air in the housing for my use.

[Cadman-iac]

  Lars,
That would work, but remember that it will still have the side load, or pressure of the belt pulling on the shaft and front bearing, not so much on the rear bearing. But the front bearing is the one that retains the shaft in the correct location, so if it's not anchored properly, then shaft and vane housing will slip forward until it hits the inside of the case, resulting in excessive wear, noise, and possibly loosing the belt, and with it goes your water pump and alternator.
Between the two options that you are considering, the crank pulley is the better choice in my opinion.
  I just wanted to give you all the possible problems that you may encounter with trying to modify the smog pump.
  Rick

 P.S. Have you considered just buying a rebuilt smog pump and running everything as designed?

[IcebearLars]

Hey Rick,

thanks for your thoughts and I fully agree on the load for the front bearing - will check what force is needed to get it in - otherwise I have to secure it in some way in place. Think the option with the two component glue is probably the easiest one - just get the plastic out, grind some groves in the outer bearing surface and glue it in with the glue - it will creep in the groves and concrete it in forever I guess.

Can't use a (refurbished) smog pump as it was since during taking the heads off the one side of the connection pipe gave up (see post #53) - and - here in Germany historic cars don't have emissions to achieve at all - so no need of it.

But you are spot on the thought about "why using a pump if there are other achievable options available" like the modded pulley.

So many things to go through during having the engine apart - that's really exciting!

[Cadman-iac]

  Well the good thing about the way that pump was designed is that the shaft cannot come out of the housing on its own. It would make quite a mess of the housing if the bearing comes loose if the belt doesn't come off first.
 Sorry for the gloom and doom, but I'm always thinking of how things can go wrong in order to anticipate them and hopefully prevent them.
 I completely understand though about not wanting the system on the car if it's not required by your country. I feel the same way.
 Please update us on how it works out. I'm definitely curious about how you will keep that bearing in place.
 And I admit I have an ulterior motive for knowing, as I'm going to have to make mine work again eventually. Although the truck isn't affected by it not being in place, I want it back on there anyway.

 Rick

[Cadman-iac]

I just had a thought, what if there were a lip or flange on the inner edge of the front bearing that would keep it from going forward once in place? It can't really go backwards since it's stuck on the shaft, and the shaft won't go back any farther because of the rear bearing and housing.
Something maybe that you could spot weld to the outer race on the bearing, like a big thin washer. And I say "spot weld" because of the seals on the bearing.
Just a thought. Never stop trying!!

Rick

[IcebearLars]

By design the whole thing can travel in both directions if the front bearing gets lose.
Making a mess on either side of the housing - not an easy one but we will get there.

Will keep you updated as soon as I get the new bearings - at that time I can try whats possible and how tight things are sitting in the housing.