Hi guys I've got a 1981 f100 with its original 351 Cleveland C6, I'm just wandering is the rear main a 2 price so I don't have to remove engine and transmission I can just remove sump, and then remove rear bearing cap? If someone can let me know what type of seal is in it it would be great thankyou

 

81 should be a 2 piece. Though they never made a Cleveland engine over here after around 1973 or 1974. So I am just going by the year, none of Ford engines used a one piece rear main in 1981 that I know of.

Too bad we don't have more people from Australia on this board. Most of your questions are hard to answer because Ford offered different options over there that we didn't have in the US.

 

Not to hijack someone else's thread but how do you know if it's one or two piece?

I check online and all I see for my 86 351 W is a one piece, so I'm stuck with the big repair?

 

Yeah, Morgan, I have an 86 351W and completed this repair. Lots of work but worth it (if you do it yourself). Paying someone to do it will cost more than the truck. Mine was dumping 1 qt of oil on the ground every day before I got it replaced.

 

Mine was bad like that in my 1980 bronco 300 six. One piece. IIRC same part number as 351W but I would have to check. Do yourself a favor and sleeve the crankshaft. I have the part number for that too but I'm not at the house. There were two available sleeves one was like half the price of the other and came with a tool to install.

 

82 please elaborate on the sleeve.

I'm sure Johno is paying attention with me

 

I sleeved mine too. It's basically a thin, round, metal sleeve that goes on the end of the crank (where the seal rides). If your crank is pitted, worn, etc, it will give you a nice, smooth, clean surface for the new seal. It will also stretch the spring in the seal slightly more than stock crank surface.

The "tool" is a simple plastic cup looking thing that the sleeve goes inside. Then you can hammer on the back side of the cup to get the sleeve to go on straight. The install tool was also helpful for putting the seal in.

 

So because my rear main seal is a 2 peices all I need to do is remove my sump and remove rear bearing cap and I can replace it ?

 

I was just going by the date of your engine. Why don't you go to one of your local parts houses in Australia, or however you get parts, and tell them you want a rear main seal for your truck. They may hand you a 2 piece seal, or being a Ford there may be a big debate on it. Sometimes Ford changed things mid-year. Who knows what they did over there down under.

As far as the sleeves go, they make them for several different areas. One place it's used often is the crankshaft damper on the front of the engine. The rubber seal will actually wear a groove in the steel sleeve surface, so the sleeve fixes this. Same with the rear main.

 

Didn't understand any of that, all I want to know is can you replace a 2 price rear main by removing the sump

 

"All you need to do..." Those are words that will strike fear into the heart of any mechanic picking up a job at the start of his shift.

Dropping the oil pan is no small feat on a Ford truck. No idea of the differences on an Australian version, but here's my experience with a US-spec '84 351W:

https://www.ford-trucks.com/forums/1...y-84-351w.html

There was very little clearance between the oil pan and crossmember. There was virtually no room to slide the oil pan forward until the engine was lifted several inches. The pan would catch on the rear main bearing cap, preventing any forward movement until there was enough vertical room to drop the pan underneath.

I've changed two-piece rear main seals on other vehicles, and it required loosening all the main bearing caps. Even with a Sneaky Pete, there was just too much friction until all the caps were loosened so the crank could drop slightly. Your mileage may vary, but i expect you will encounter the same issue. If so, the oil pan would have to come all the way out.

Sorry I don't have a happier answer for you.

 

I was thinking of lifting engine with a engine crane until it hit the firewall, the taking oil pan off and just removing rear bearing cap and tap out the peice of the seal that goes over the crankshaft and the pull it with pliers from the other side and then slide the new one in by hand and use a hammer and punch to get it all the way round? Is this how it's ment to be done will it work this way

 

Spring for a Sneaky Pete:

Lisle Corporation

That version is from Lisle but other companies make similar ones.

When you tap on one end of the seal, whether removing or installing it, the length shortens slightly, which causes the cross section to swell and jam. Once it jams, further pushing only wedges it tighter. Pulling works much better, because this causes the cross section to shrink and reduce jamming. If it does start to jam, pulling harder usually works it free. You wouldn't think pulling vs. pushing would make much difference, but it does.

The corkscrew tool is used for removal. It will damage the old seal, but that won't matter since it will be replaced.

The other tool is used for installation. It is fed through the empty gap first, and then it pulls the new seal into place from one end. That brand has a little clip that grabs the seal. The one I have (don't know the brand) has a bit of braided steel sleeve that grabs like Chinese handcuffs.

 

It is a 2 piece rear main seal ALL the production 335 series engines 302 Boss 302C 351C/Boss 351M and 400 all only ever used a 2 piece rear main it s the same part as the 351W 2 piece main seal.


You do not need a sneaky pete that is only needed for the old style rope seals that have pretty much been replaced with rubber 2 piece seals.

You will have to drop the sump and the rear main cap. If you do not have clearance to remove the sump pan unbolt the motor mounts and raise engine, then place a short piece of 2x4 lumber (90mmx45mm) between the mounts and engine block then lower the engine back down. This will give you the clearance you need.



After removing the rear main cap you "may" (usually you can) be able to push the old seal out around the crank, the core of the seal is a steel rod so be sure to push on that, a 1/4" socket extension works good for getting it moving or a punch of appropriate size. I like using a 1/4" extension as all the sides are rounded and have less chance of marring the crank. Be extra careful not to mar the crank.

If one side of the seal is sticking up (as it should be) you should be able to grab it with a pair of visegrips (locking pliers)and pull it out. Again be careful not to mar the crank.

If the seal wont budge you will have to remove the oil pick up and loosen the rest of the main caps 1/8 to 1/4" (3-6 mm) and let the crank drop that amount, that will give you the clearance needed to pry the seal loose form the engine block.

When installing the new seal coat it in motor and carefully slide it back in to place around the crank in the engine block being sure not to shave any material off the seals faces. Make sure you have the seal offset (not flush with engine block) it should stick up 3/8" (9-10MM) on one side. Also be sure to have the seal in the correct orientation. (Lip pointing to front of engine).
Coat the seal going in to the main cap with motor oil and install making sure it is bottomed out in the cap , check that the offset in the seal will match the one in the engine block and is sticking out the same amount.


If you loosened all the main caps reinstall as per factory specs torquing in 3 steps, then install the oil pick up, If you just had to drop the rear main install and torque to specs in 3 steps.

This is also a good time to clean any crud off that is stuck to the screen of the oil pick up tube.

Hope this helps.

 

Hi mate thanks for your explanation this will really help, just a few more questions, by. Hence would you know the torque specs for 351 Cleveland main caps and sequence for torquing them, also do you have the torque specs for the motor mounts and oil pan? Thanks