Doing Head Gaskets, should I do the rear main too?

[mike97d1]

Like the title says, I'm about to do the head gaskets on my D2. Will probably do the front cover at the same time. I'm debating on if I should just pull the motor and do the rear main / crucifix seals at the same time. Truck has almost 130K on it. So what's the consensus, is the rear main a common enough issue that i should pull the motor and do it to? Or leave the motor in the truck and just pull the heads?

 

[Spike555]

I would not worry about it until it leaks.
If it ain't broke...

 

[*NR*BRENT]

Id leave the rear main alone, just my 2 pennies

 

[bmxer06pa]

Mine is leaking. I wish they had dome mine when I had my head gaskets done.

 

[The Fourth Amigo]

If its not leaking I wouldn't touch it. I've seen them leak after being replaced.

 

[JohnB]

My main would have to be really leaking before I would pull the engine to replace the rear main. I almost have 170K and not leaking much of anything but like you I did my head gaskets around 120 so a new pan gasket and front seal was done at the same time.

 

[d1driver]

By the time you get everything pulled to do the heads, about the only thing left is the block. If I had to do it again, I would pull the block and put in new crank bearings, seals, etc.

I changed head gaskets and rebuilt the heads on mine. Not very long afterwards, it developed a low oil pressure problem. Turned out the crank bearings were shot. I wished I pulled the block when doing the heads.

Besides, doing a headgasket job and everything else is much easier on an engine sitting on a stand. Depends on your ambition.

 

[mike97d1]

Well, I decided to go ahead, pull the motor and re-seal everything. Good thing I did cause I found one of my motor mount was broken. Looked perfect, but one side was completely seperated. Hoping to have it back together by saturday night. Wish me luck!

 

[p m]

That brings up a question I seem to be asking the engine people every once in a blue moon.
Once you have the motor out and oil pan off, does it make sense to replace the rod and main bearings?
Once the heads are off, does it make sense to at least replace the valve lifters?

 

[aliastel]

I'm freshening a 4.6 for my D2 right now and have been considering these issues too. I'm replacing the head gaskets and installing studs and a new water pump, as well as oil pump gears and checking the oil pressure relief valve. As far as the bearings, I think it would have to depend on the mileage. My motor has 97K on it, and the oil pressure is good, so I'm passing on that. On the lifters, I believe you have to do the cam too if you do the lifters. My cam is in good shape so I'm going to pass on that until the next head gasket job. I might replace the main seal since the motor is out. I'm also going to replace the crank sensor.

David

 

[mike97d1]

Main bearings and rod bearing should be good for way more milage than my motor has on it right now. It's just the odd rover head gasket issue that even started this process. If the entire motor wasn't so dirty and coverd in oil and mud I probably would have left it in and just done the head. That said, I had a few friends helping me, so I figured what the heck, pull it, clean it, proceed. I guess you have to draw a line somewhere. The cylinder walls looked great, valve were suprisingly clean, cam and lifter look great, i'll see what the bottom end looks like tonight, not that you can see enough to tell if the bearing are funky.

 

[d1driver]

I still say replace the crank bearings if you are already in that far. It's not that much work and the peace of mind of solid oil pressure is worth the cost.

 

[archaeology_student]

As bmxer06pa says:

Mine is leaking. I wish they had dome mine when I had my head gaskets done.

I just had my head gaskets done, and it was worth removing the engine and doing the rear main as mine was leaking.

You may as well do it now as it could save you headache down the road in terms of labour and cost to replace it.

Good luck!