Well, on Sunday I attempted to replace the rear main seal in my 80 F100 while leaving the engine in. I pulled the tranny and flywheel to have more access, but due to a lack of tools and the cross member, I could not pull the oil pan all the way out. I was able to lower the pan enought to replace the rear main, but I do not hink I did it right. Due to the same difficulties, I was only able to replace the bottom half of my rear main seal, but the piece seemed to be too long. There seemed to be a gap or something. Either way, I put everything in as best as I could but now, I can see puddles of oil from under the oil pan/transmission. Any ideas on how to do this project dorrectly?

 

You have to loosen the crank mains to repace with a oem type seal, in many cases, you have to lossen the engine & trans mounts then raise the engine/trans up a coule of inches to remove the pan, then you can get to everything. One option, some people like this and some don't (the real old timers like myself personally like this), sometimes the oem type seals can be a real pain to install especially on the top side of the crank....and it seems the replacement seals go through manufacturing phases where their quality is sometimes excellent and sometimes not that great which you don't realize until the install is complete & here comes the drips. I personally like what is knwon as a "rope gasket". It is a round rope like seal that has a very thin wire attached to one end, allowing you to feed the wire up over the top of the crank and then pull the gasket completely through, then using a knife, cut the excess off, install the bottom and you're done. The cons of this are that probably about 30% of the time, you will have a very, very tiny drip, but so small is really makes little diference except the need to place something under the car to keep your driveway perfectly spotless. I have never seen one fail or every require replacement once installed.

 

That is one thing I was afraid of. It took me all day on Sunday just to replace thae bottom portion of th seal. I have no way of lifting the engine so it was very difficult. I read an old post from someone who used a K & N OIl Leak Stop for a similar problem and they say it has worked very well. Does anyone think this is a good option? Also, with my manual transmission, will a rear main leak cause my clutch to slip?

 

When my rear main went out in Hoss, it soaked the clutch pretty bad and it caused the truck to slip on take-off and even while I was driving it would slip.
I wouldn't suggest trying any fix-it-in-a-can crap, it won't help long term. The only way to do it right is to replace the rear main just like the books tell you to.

 

I figured that was true. I guess I am just dreading trying to do that again. What is the best way to lift the engine up a few inches to remove the oil pan. Is there an easy way to do it without a lift? My manual says to use a jack and some pieces of wood, but I do not think my jack will go high ehough to lift the engine. Can I jcak the oil pan and use something to prop the engine while I lower the oil pan?

 

I have lifted by pushing up with the block of wood on the pulley or harmonic balancer. You want to be careful doing this, as it can cause more trouble if you get carried away and try to force it up. I would raise it up, then put something under the motor mounts to keep it from coming down on you while you work. Take a long 4x4 piece of wood, place it on your jack, then push it against the balancer that way, You can use a 2x4, but I prefer the 4x4 for better stability. You have it standing on end to beable to reach up and push. Be aware of your fan shroud and fan blade in relation to the radiator though.You should be able to turn the engine when you replace the seal, as you can actualy spin it out and then the new one in using the crank to help. The old one will be tricky to get started moving, but will come.Lube the new one to help it spin into place(the block side of the seal) It will stay when the other half is installed.

 

Thank you all for all of your help. I will have to try this weekend to get this done. It is so frustrating to have to redo work, but this is what I deserve for half - @$$ing my original work. I will keep you posted on how the project goes.

 

degdawgs, what size engine do you have?

 

"Democracy is when two wolfes and a sheep vote what to have for dinner."

Liberty is a well armed sheep contesting the vote......

 

Gotta learn sometime, I just happen to be further down the road of learning how to get things done...

 

My recommendation, rent a hoist and pull the engine so you can do it right.

 

degdawgs, if you want I have the rear main oil seal instructions from my shop manual.

The 4.9L doesn't have a 2 piece seal.

 

Thank you, SierraBen. I have a Haynes Manual, is yours any different? I tried to use the haynes and it has good instructions, but I thought lifting the engine would be too hard. I see now that it may be easier than I thought. Any information you have would be appreciated and, again, I thank all of you for your helpful advice. I know it will make everything much easier for me.

 

Autozone online manual Well, it looks like you have been going at it wrong, and I went with it... your choices are simple, pull the motor or pull the trans. Then you can get at the main seal, as it is one piece.

 

degdawgs, would this help?; if you don't have a 4.9L.