76 K10 rear main seal

[Fjordlander]

Hi all,

I apologize if this has been covered but I wanted advise on my specific year just to be sure.

I have a 76 K10 Scottsdale and the PO of my truck told me the rear main seal was leaking and based on what I've read I believe that's correct. My question is, how big of a job is it to replace the rear main seal?
My understanding is that I have to remove the oil pan to replace it but all my mechanical experience has been working on this truck with the advice I get on this forum so I want to make sure I'm not biting off more than I can chew. Id rather pay to have someone do it right than risk ruining something if it's a big job. I appreciate any and all advice!

 

[GTX63]

If your truck has the original motor, or, if the motor is pre 1986, then it will have a two piece rear main seal. Dropping the oil pan, the pump and the rear main cap to replace the seal is, IMO, something that can be done by someone with a moderate set of tools and common sense.

 

[fast 99]

Only technical part is rear main cap and oil pump torque. Otherwise, it's just bolts. Messy job but easily done with common tools and a little patience.

 

[Fjordlander]

If your truck has the original motor, or, if the motor is pre 1986, then it will have a two piece rear main seal. Dropping the oil pan, the pump and the rear main cap to replace the seal is, IMO, something that can be done by someone with a moderate set of tools and common sense.

It's not the original motor but the PO told me it's a 2 piece rear main seal so he must have put in a pre 86 motor. I appreciate your advice!

 

[Fjordlander]

Only technical part is rear main cap and oil pump torque. Otherwise, it's just bolts. Messy job but easily done with common tools and a little patience.

Okay thanks! I'll plan to do it myself

 

[Old Guy Bill]

A “Sneaky Pete” tool will be required to get that job done easier…
The top half of that seal can be a real pain some times. Just sayin..

 

[fast 99]

A “Sneaky Pete” tool will be required to get that job done easier…
The top half of that seal can be a real pain some times. Just sayin..

Sometimes they will stick a little. I use a seal pick, pull on one side and push with an extension or screwdriver on other side. Have always been able to get upper 1/2 out that way. Just be careful and not nick the crank. In frame like this get a 1-piece pan gasket.

 

[Snoots]

While you have the oil pump out, tack weld the pick-up screen to the tube and the tube to the housing.

 

[idahovette]

Just make sure it's in the right position before you tack it^^^^^^^^^

 

[Fjordlander]

I don't think there's anything wrong with it but is there any reason I should replace the oil pump while I'm replacing the rear main seal?

 

[Ricko1966]

I don't think there's anything wrong with it but is there any reason I should replace the oil pump while I'm replacing the rear main seal?

I wouldn't bother,Chevy small block pumps,almost never fail,and the quality of parts these days you may not get as good as what you've got. If your worried inspect your pump,that's what people used to do,measure the clearances. I'd be more tempted to pull a rod cap and check bearings possible spin in a set while I had the pan off. More SBCs die from rodvbearing clearance than oil pump failure.

 

[Fjordlander]

I wouldn't bother,Chevy small block pumps,almost never fail,and the quality of parts these days you may not get as good as what you've got. If your worried inspect your pump,that's what people used to do,measure the clearances. I'd be more tempted to pull a rod cap and check bearings possible spin in a set while I had the pan off. More SBCs die from rodvbearing clearance than oil pump failure.

Perfect. That's what I needed to know. Thank you!

 

[Dleslie212]

I wouldn't bother,Chevy small block pumps,almost never fail,and the quality of parts these days you may not get as good as what you've got. If your worried inspect your pump,that's what people used to do,measure the clearances. I'd be more tempted to pull a rod cap and check bearings possible spin in a set while I had the pan off. More SBCs die from rodvbearing clearance than oil pump failure.

Is it a decent idea to just change all the rod bearings while the pan is down?

 

[Ricko1966]

Is it a decent idea to just change all the rod bearings while the pan is down?

Pull a couple. Are they showing copper? Then yes, definitely spun in a set. A lot of the time if doing head gaskets, I'll do a valve job, rings and rod bearings at the same time, that way I know I've got a generally solid engine for a long time. I've spun in rods lots of times,mains occasionally,if I've got the pan down its not much work to change them. As I said before small block Chevys throw rods 100 times more often then they have oil pump failures.