1970 Cadillac drop the oil pan - exhaust 'Y" pipe - does it need to drop too?

[Scot Minesinger]

Performing a full mechanic restore on a 1970 Cadillac RWD 472, SDV.  The suspension is finished -thanks for help on tie struts.  The steering linkage is removed, and now it is time to drop the pan so I can replace rear main seal and timing chain.  I just replaced the exhaust so the manifold to "Y" pipe nuts are not jammed-rusted or frozen.  Do I have to drop the exhaust "Y" pipe to remove the oil pan. 

Ii is understood that if I did not want to replace rear main seal, just having the pan rest on the "Y" pipe would be OK to replace timing chain, but plan to replace the pan gaskets and recondition the pan to like new Cadillac blue too.

Thanks for the experience in advance.

[The Tassie Devil(le)]

If it is in the way, then remove it.

If it is not in the way, then no need.

You will need a lot of room under the engine to get the sump out, and this will probably include raising the engine a couple of inched to allow the front to clear, and to access the bolts.

Bruce.

[Roger Zimmermann]

What is the shop manual saying?

[Gene Beaird]

I haven't done that particular car, but if it is easy to remove, and is it not obvious you can get the job done with it in place, I'd drop it.  I recently did a clutch on our 95 Z28, and things are so tight under there, I was pulling parts while trying to get to everything I needed to to get the clutch, flywheel and pilot bearing out.  It was so frustrating to be trying to get to a bolt, or a better angle to do something, and then have to stop to remove yet another part from the car. 

So, yeah, I'd do it now, before you have the pan half way out, old oil all over your hands and then realize you have to drop the Y. 

[Smedly]

I did this on my 73 sdv and yes it will be much easier to remove the y and get it out of the way.
Sheldon Hay

[Vinny6t6]

I replaced the rear main seal on my 66 429 over the summer.  I had to remove the Y pipe and the center link along with the starter and torque converter cover.  Made it alot easier and I was able to look over the bottom end and oil pump pick up tube too.  It also makes it easier when replacing the oil pan gaskets along with front and rear oil pan seals.

[mgbeda]

I wanted to mention something of great help that I learned on the forum.  A 50/50 mixture of ATF and acetone makes a miracle penetrating oil.  I didn't believe it myself until I tried it, which was halfway through disassembling Bessie's exhaust.  All the bolts I used this on came free.  All the bolts I didn't use this on broke.  Give it at least overnight to soak in.  I hope it will save you having to drill out broken manifold studs.

Just don't get it on any good paint; it'll strip it right off.

-mB

[Scot Minesinger]

Thanks, sounds like the exhaust y-pipe must be dropped.

Plan on removing the pan tonight and will post after that.  The starter and center link are off the car because it was obviously required.  The exhaust system, including Pipe was replaced a few months ago and should not be much of an issue, just wondering if it had to be done.  Yes, I have used that 50% acetone and ATF and have a jar in my cabinet for this purpose - it does work miracles.  Removing the pan to replace timing chain, front and rear main seals, and oil pan gasket.  Since the pan will be off the car, will media blast and paint it.  This is a 35k miles car that ran well before I started, but from prior posts the concensus was to replace the chain regardless, so the pan had to be dropped.  Might as well reseal and refinish too.

[Aprules2]

Im not sure if its a similar frame design, but on my previous 75 coupe, I couldnt get the oil pan out with out dropping the exhaust, tie rods, and center link, I also had to take it off the engine mounts and jack it up. I hope yours comes out easier. By the way check the pan for plastic garbage, if there is any then take the pickup off, and make sure you clean it out.

[Scot Minesinger]

Oil pan is off the car.  The entire steering mechanism was already off the car, and so was starter and flywheel cover.  That y-pipe had to be removed, no way around it to drop the pan.  Except for oil, there was nothing in the pan.  Attached are some pictures - the cylinder walls like nice and you can see the text "CAD.." on one of the cylinders.  This weekend will replace the timing chain, got to get to media blasting the exterior of the oil pan and paint it (I know only bare metal from gasket and in).  For others who perform this job in the future will document with some pictures.

[Gene Beaird]

You gotta love seeing the cross-hatching in the cylinder walls.  Nice.