Water pump replacement on a '92 460 - a few questions
 

Posted this on the 460 Big Block section but received no responses.

Changing out the water pump on my 1992 460.

Questions:

1. Is it recommended to also remove the aluminum cover behind the water pump and replace its gasket?

2. What all is involved in replacing the cover gasket? I know there is a paper/fiber gasket similar to water pump gasket, but are there other gaskets behind cover that will also need to be replaced (ex rubber seal to timing chain cover)? Is removing this alum cover opening a can of worms with regard to timing chain and related parts?

Currently, these parts are not leaking. I am replacing water pump, as I am replacing the radiator and figure it wouldn't hurt to have a new water pump in there.

Thanks

You're OK to just replace the water pump gaskets.

If you replace the timing cover gasket you'll likely have to loosen the oil pan to allow you to install a new front oil pan seal that seal between the timing cover gasket and oil pan. That MAY open up a place for an oil leak if you are not careful.

Now if you want to check the timing chain condition and/or replace it that's another matter.

I haven't done a 460 (yet), but I've heard it's similar to the 302 in this area. When I changed the water pump on my Bronco last summer some of the bolts were really stuck (not uncommon it turns out). I ended up needing to take the timing cover off to get some of the broken bolts out. wasn't a big deal for me because I was replacing the timing cover anyway (switching back to V-belts from a serp setup I had installed earlier). But if it goes for you like it did for me you might not need to make that decision:-roll

But if you don't need to, I'm with krooser. Don't give the oil pan an opportunity to become a problem if you don't have to (it can be a real pain getting the oil pan out and back in with the engine in the vehicle too).

After thinking about this, I can;t imagine having to take the timing cover off and replace related gaskets, including oil pan seal....just to replace water pump? Am I correct?

Water to/from the water pump runs through passages in the timing cover. Some of the water pump bolts are "wet" bolts, meaning the ends of them are exposed to coolant flow. Sometimes these are a pain to remove, and sometimes just snap off no matter how careful you are.

Starting at the water pump and working back to the block, there are 3 gaskets: water pump backing plate to water pump, water pump to timing cover, and timing cover to block. It would be wise of you to have all of these before starting the teardown.

If you don't have to remove the timing cover, great! If so, might as well put in a new timing set while you're there, so you won't have to tear the front of the engine apart again anytime soon.

What Dixie said. Plus the front of the oil pan attaches to the bottom of the timing chain cover, hence the continuing cascade.

I think I've heard of people not taking the oil pan off, only removing the bolts that go through it into the timing cover, and then just resealing that area rather than mess with the entire oil pan. I have not tried that though. It sounds to me like it would be challenging to get the oil pan sealed that way, but maybe it works out well.

Yea not that hard to do, remove pan bolts into timing cover loosen couple back down each side of pan. loosening pan bolts couple three back on each side make it easier the get the cover off but more importantly easier to get it back on and without loosing the rubber seals positioning in the process. Normal order is timing cover first then the oil pan, doing so other way around isn't ideal no but is doable and without ending up with a leak.

I use Hightack spray a gasket to get the front pan seal adhered into its grove in the cover, couple of light coats in the grove same on seal then once tacky firmly press fully into place and let set few minutes to dry, it must hold or it will come out when putting the cover back in place.

I have done a few of them and I do not cut the front of the pan gasket off using those little pieces included with the gasket set for the cover, clean it apply high tack then little dab of silicone in the corners. IMO cutting off the front sections of pan gasket might tend create more problems than its worth. Depends on the pan gasket too though, cork wouldn't hesitate cut it back use the little pieces included, stock reinforced rubber gasket no.

Anyway its not a hard job just takes little extra time, already at the cover anyway IMO its not worth the chance. Maybe if the pump bolts come out butter smooth but I've yet to remove one where that has been the case on a ford. More often than not requires heat to remove the bolts, to do so without breaking them off inside the cover/block, that happens you're removing the cover anyway so might as well not snap them off to start with.

If water pump bolts do not break during removal, can the water pump and gasket be replaced without doing anything further?

Yes if the water pump bolts come out clean the pump can be changed without getting into the timing cover.

Your engine does look like a fairly good candidate, a little rust yes but nothing to the extreme like tend to find around here.

Looks can be deceiving there is no way to know for sure until you actually try to remove the pump bolts and because they enter the water jackets. Those bolts pass through the timing cover but do not thread into it, its a moisture trap and one between two dissimilar metals.

I'll give it a shot in the next day or two and see what happens. Fingers crossed! too bad there's no way to spray 'em with some liquid wrench.

The WP gasket that came with the NEW Motorcraft water pump looks pretty thin. I'm going to see if the Fel-Pro Blue Stripe is any better/thicker.

If they act like they are going to twist off, just take a die grinder and cut the heads off and slide the timing cover off over the headless bolts. Then heat them real good with a torch and remove them with vice grips. When you replace them, anti-seeze the crap out of those bolts! I know you didn't want to do the timing cover gaskets, but if you twist a bolt you'll be doing alot more work.

While you do want to spray little bit of penetrate on the bolts you do not want to flush the timing cover to block area with lots of it especially once the bolts begin to loosen, it would tend to damage the gasket between the two soften it to point it could create a leak once and up to temp and pressure again.

Myself I use straight trans fluid in a old style oil can, similar to this but much older trigger not thumb. Trans fluid works better than all that stuff they sell do so otherwise on rusty parts.

http://cloudfront.zoro.com/product/full/1EKE7_AS01.JPG

You'll want something thin at least initially that will tend to get into and around the bolt shaft between it and the timing cover.

The bolts don't tend to break so much from being screwed into the block rust there that is a problem area too yea, the big problem tends to be where the bolt passes through the timing cover.

Little bit of coolant leaks past the threads of the bolt filling the air space around the bolt between it and the cover, the two dissimilar metals corroded in that environment, that corrosion builds up expanding until locks bolt sold in place.

Comes down to sealant used on bolts when the pump was last installed.

Its a "feel" thing, are you turning the whole bolt or just twisting it until is finally breaks off, fairly long bolt as bolts go on a engine and makes it harder to feel for and certainly can't see it going on.

I'll just try and loosen without any penetrant, as I want to avoid having to remove alum timing cover.

If successful, do I use the same bolts, clean them up on wire wheel, and use anti seize? Or should I use all new bolts?

Clean the holes and use Loctite PST on the bolts.
It is made for sealing bolts going into the water jacket and is 'controlled torque', i.e. it does not add an appreciable amount of effort to remove.