Blazin'4x4
1/2 ton status
Anyone have any tricks to replacing the oil pan gaskets while the engine still in?
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Rear main seal tricks
- Thread starter Blazin'4x4
- Start date
wasted wages
1 ton status
rear main crank seal or oil pan gaskets ???
Blazin'4x4
1/2 ton status
Last I remember they all come in the same kit. If im wrong then the rear crank seal is my problem that needs attention. Its a very common problem with 350s so I should be able to get some good insight.
lak2004
1/2 ton status
I believe you can unbolt the tranny and pull the flexplate/flywheel and get to it that way. You will have to probably pull the rear d-shaft so you can move the tranny/tcase back a little to get to it. You may also have to pull the oil pan. What year engine?
Blazin'4x4
1/2 ton status
72 350, Think I can just support the engine and un bolt the crossmember to access the seal?
wasted wages
1 ton status
uuummm.... no
the rear main crankshaft seal is not the same as the pan gasket seal at the rear of the pan.
Chevy has two styles of CRANKSHAFT seals,,,older models use a two piece seal that requires removal of the rear main bearing cap.
This type can be done in the truck.
The newer one piece rear main seals require removal of the transmission and flywheel as the seal is pressed in the rear of the engine,, over the end of the crankshaft.
now if your talking about the rear rubber seal on the ends of the oil pan then yes they come in the kit with the pan gaskets and can be done in the truck also.
but don't confuse that with a rear main crankshaft seal...
the rear main crankshaft seal is not the same as the pan gasket seal at the rear of the pan.
Chevy has two styles of CRANKSHAFT seals,,,older models use a two piece seal that requires removal of the rear main bearing cap.
This type can be done in the truck.
The newer one piece rear main seals require removal of the transmission and flywheel as the seal is pressed in the rear of the engine,, over the end of the crankshaft.
now if your talking about the rear rubber seal on the ends of the oil pan then yes they come in the kit with the pan gaskets and can be done in the truck also.
but don't confuse that with a rear main crankshaft seal...
lak2004
1/2 ton status
Which crossmember? On the tranny, if so then yes move the tranny back and support that as well
Blazin'4x4
1/2 ton status
How would I tell which is leaking between the two? If I let my truck idle, I would lose a quart every ten minutes.
wasted wages
1 ton status
sounds like the rear crank seal...
to remove the oil pan,,unbolt the motor mount bolts,, lift the front of the engine and the pan will clear for removal.
to remove the rear crank seal,,drop the oil pump, unbolt the rear main and remove,,,1/2 of the seal will be in the cap,,the other 1/2 will be in the block.
the one in the block can be pulled out with needle nose pliers,
CAREFULLY,,don't gouge up the crank journal...
the new one will need to be rolled into place,,use a little permatex
not silicone,,on the backside of the seal,make ssure the lip faces the same way as the old one !!!! ,roll the crank over as you push the new one into place, if needed. oil the seal and crank good after it is in place.
change out the seal 1/2 in the cap,,,Lube up the bearing and seal
and torque it down.
install the pump and pan,,bolt down the motor mount bolts and your done.
Blazin'4x4
1/2 ton status
Sounds like your fresh out of chiltons! 
Thats awesome though thats exactly what I was lookin for. thanks.
Thats awesome though thats exactly what I was lookin for. thanks.78K5Blaza
Registered Member
If you get a rubber Oil pan gasket they come with retainers to hold the gasket in place while you put the oil pan back.
Wasted Wages, explained the whole process. While you under there replace the front seal as well, as I replaced the rear 3 weeks ago, now the front is loosing oil...learn from my oversight or learn for yourself. The front will leak next.
Wasted Wages, explained the whole process. While you under there replace the front seal as well, as I replaced the rear 3 weeks ago, now the front is loosing oil...learn from my oversight or learn for yourself. The front will leak next.
wasted wages
1 ton status
I've done one or two.....
wasted wages
1 ton status
one more thing,,,rubber and silicone dont play well together...
I've seen more seals,,,rubber gaskets,, pop out when some one used silicone for a repair,,,the stuff is just to slick,,and lets rubber stuff slide around too much before it sets.
I use aviation form a gasket ( high tack ) for pretty much all gaskets and seals,,,good stuff.
I've seen more seals,,,rubber gaskets,, pop out when some one used silicone for a repair,,,the stuff is just to slick,,and lets rubber stuff slide around too much before it sets.
I use aviation form a gasket ( high tack ) for pretty much all gaskets and seals,,,good stuff.
I've done a couple of rear main seals and you don't have to jack up the motor unless it is a 2 wheel drive with the crossmember right under the motor. And I always used an oil pan stud kit. Put the gasket up on the studs and it will stay there to easily get the pan back on.
Tarey
Tarey
buffblazer
1/2 ton status
or you could just pull the motor and re seal the whole thing my head gaskets went and i was like eh might as well do it all so im not back at it in a couple of months
my head gaskets went and i was like eh might as well do it all so im not back at it in a couple of months
Blazin'4x4
1/2 ton status
I wish I could just pull the motor out. Then I know I would end up rebuilding it, then the tranny, t-case, then why not a frame off resto.........Just to make my engine quit leaking.
jonathon
1/2 ton status
I used this thread to do mine in my K5
http://www.4x4mecca.com/forum/vbarticles.php?do=article&articleid=27
It was pretty easy. Worst part was putting the oil pan back on. Get the one piece gasket, it makes life EASY.
Fixed most of my leaking, the intake leaks a little I believe, but I'm not going to mess with it since I'm hoping to put a crate 350 in next year.
http://www.4x4mecca.com/forum/vbarticles.php?do=article&articleid=27
It was pretty easy. Worst part was putting the oil pan back on. Get the one piece gasket, it makes life EASY.
Fixed most of my leaking, the intake leaks a little I believe, but I'm not going to mess with it since I'm hoping to put a crate 350 in next year.
buffblazer
1/2 ton status
i did exactly that. my head gaskets started leaking and i said ahh what the heck i will just re seal the entire motor
next thing i know im trying to swap in a nv4500 re seal it and possibly rebuild it
now my baby has been sitting for 4 months and its the summer season and no fun for me
should have left it in and did the head gaskets in frame.
This sounds exactly like what I read out of the Haynes book for the similar year. I read this same fix/replacement just two nights ago and he was spot on. Being a noob myself I would highly recommend this book. It is worth the $25 or so it costs. I have to do the same seal replacement in mine.
Hoby
