1973 Riviera oil pan question

[BfromNC]

My oil pan gasket is shot. I've been told that the engine needs to come out to access it. I was wondering if anyone makes a one piece gasket i could slip through the gap between pan and block and mount that way? 

[NailheadBob]

I do not know of any one piece gasket for your car, but you could use Dorman # 45722 oil pan gasket tool set, once oil pan removed and old gasket cleaned off, you screw this tool in 4 locations on engine block where oil pan bolts go, then position gasket in place, then the oil pan in place , the center of the tool holds pan up and use your second hand to keep it in place, so you can start several bolts, then just unscrew the tool. FelPro also makes them # ES-72863 5/16", ES-72864 6mm, and ES-72865 3/8", this is what I would try before I would remove engine to replace oil pan gasket.

 

Bob

Edited July 17, 2022 by NailheadBob
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[Rusty_OToole]

The usual problem is clearance between the engine and front crossmember. Solution is to unbolt engine mounts and jack up the engine. And turn the crankshaft until the front rods clear the pan. The pan can then be slid out the back.

Usually (always) the bolt holes are dimpled and the gasket will not seal until the pan is hammered flat. And, you need to clean any sludge out of the pan. So the pan has to come out to do the job properly.

[joe_padavano]

12 hours ago, Rusty_OToole said:

The usual problem is clearance between the engine and front crossmember. Solution is to unbolt engine mounts and jack up the engine. And turn the crankshaft until the front rods clear the pan. The pan can then be slid out the back.

Usually (always) the bolt holes are dimpled and the gasket will not seal until the pan is hammered flat. And, you need to clean any sludge out of the pan. So the pan has to come out to do the job properly.

Unfortunately by the time you go through all of this, you're about six bellhousing bolts away from just pulling the engine. Plus, even if you do manage to get the pan off with the engine in the car, now you're working under it with oil dripping in your face. Pull the motor, put it on a stand, and do it right. Of course, that always raises the risks of the MIGHTASWELLS. An oil pan gasket can easily turn into a complete engine rebuild and engine compartment detailing. Ask my how I know... 😲

[EmTee]

19 minutes ago, joe_padavano said:

An oil pan gasket can easily turn into a complete engine rebuild and engine compartment detailing. Ask my how I know... 😲

So, how bad is that leak anyway...?

[BfromNC]

Pretty bad leak. I posted on another forum about a youtube video where a guy with a chevy truck drops the oil pan without jacking up the engine. All he had to do was put the engine at top dead center and the darn pan cleared the crank. 

Here's the video. Watch it before you write it off.

 

[EmTee]

Yeah, so what?  Chevy trucks I've seen have tons of room between the pan and crossmember.  Steering components (esp. on 4x4s) is hung below the frame.  Trying to drop the pan on a car (especially a low-slung big-block Riviera) is a completely different problem.  I don't see any way to do it without somehow raising the engine off its mounts.  Of course that starts a ripple of other items such as dropping the exhaust pipes at the manifolds, disconnecting the idler arm and possibly removing the driveshaft and transmission crossmember to lower the tail...

 

Have you looked carefully at the leak(s) upward from below to ensure that the oil (or some/most of it) isn't coming from leaky valve covers?

[joe_padavano]

9 hours ago, BfromNC said:

Here's the video. Watch it before you write it off

Sorry to be brutally frank, but if you think dropping the pan on a small block Chevy in a pickup has ANYTHING in common with dropping the pan on a big block Buick in a Riviera, you probably shouldn't be the one attempting this.

[Frank DuVal]

I have done crankshaft replacements on a 307 Chevrolet Malibu, an inline 6 Maverick (200 IIRC), and a 321 Buick V-6 ~78 Regal while laying on my back with the car on jack stands in my driveway. But I was much younger then, and I am wiser now...   On the 350 Diesel in my 81 ElDorado I did not replace the crank, but did drop the pan to replace the rear main seal. But on the 455 in my Estate Wagon I pulled the engine for the rebuild, so I do not know if the pan will clear on a '73 455 Riviera, sorry. Have a shop manual?

[BfromNC]

Thanks to those with constructive answers. 

[Oldtech]

I would pull the engine if it were me, but that depends on equipment available, but as Joe says, by the time you get it up enough to get the pan off it's almost out anyway.

[Ben Bruce aka First Born]

Fwiw, in about 1980 I tore down a 1971 Buick wagon engine in my driveway,  in the car,  and installed rings and bearings.  'Course, I was only about 45.  I do not recall which engine .

 

  Ben

[Frank DuVal]

Sport Wagon or Estate Wagon? Estate Wagons were all 455 8.5:1 or so compression.