Stripped Water Pump Bolt

[ArdWrknTrk]

Several thoughts. First, are you sure that is the right sized bolt? No chance you have a smaller bolt where a larger one should go?

Second, when you cleaned out the threads in the block did it feel like the tap was loose? Like the threads are bad in the block?

If it feels like the threads in the block are bad, and you are pretty sure you have the right sized bolt, then I think I'd pull the water pump back off and get an up-close look at the threads in the block. And if they are bad then you'll have to come up with a plan. One might be to put a Heli-coil in the block.

Hey Gary—ALL the bolts are 5/16 (½ inch wrench or sockets on the hex), except for the power steering pump bracket.

BTW, Blue top went in today easy. Will post in my thread.

I was hoping to avoid taking off the pulley and harmonic balancer…ugh. The Divine has other plans for me on this project.

Ordering the kit for the timing cover tonight. UGH!

What in the world is a Heli coil? I need to research this!

Another thought—are there stud bolts that, say, might go one step higher, and then decrease to 5/16 for a nut? That would only work if this is a through and through hole into the timing chain area, which I think it might be.

From the link Cory posted it appears the bolt threads into the tin cover and not the block. (well inboard of the water inlet)

I also note the aftermarket one seems to have threaded inserts unlike what Mat says about the OEM.

Helicoils are not going to work in sheetmetal.

Replacement is unfortunately the only viable option in that case.

[Rembrant]

From the link Cory posted it appears the bolt threads into the tin cover and not the block. (well inboard of the water inlet)

I also note the aftermarket one seems to have threaded inserts unlike what Mat says about the OEM.

Helicoils are not going to work in sheetmetal.

Replacement is unfortunately the only viable option in that case.

The ProComp one shows what is basically nuts welded on the backside. I guess one could do that easy enough for a repair also. Once it is removed you could use the water pump as a template, and weld a hex nut on the backside, as long as you made sure it didn't interfere with anything.

[ArdWrknTrk]

From the link Cory posted it appears the bolt threads into the tin cover and not the block. (well inboard of the water inlet)

I also note the aftermarket one seems to have threaded inserts unlike what Mat says about the OEM.

Helicoils are not going to work in sheetmetal.

Replacement is unfortunately the only viable option in that case.

The ProComp one shows what is basically nuts welded on the backside. I guess one could do that easy enough for a repair also. Once it is removed you could use the water pump as a template, and weld a hex nut on the backside, as long as you made sure it didn't interfere with anything.

Yep. I used the term 'insert' because I didn't see any hex, but you certainly could weld a nut to the back side if the dimpled thread boss on the original isn't so big that a nut would fall through it when ground flush.

(I'd probably do both just for peace of mind)

There's often more than one way to get around a problem.

[AmericanSavage]

Yep. I used the term 'insert' because I didn't see any hex, but you certainly could weld a nut to the back side if the dimpled thread boss on the original isn't so big that a nut would fall through it when ground flush.

(I'd probably do both just for peace of mind)

There's often more than one way to get around a problem.

Here is a stripped down 351 C block. I have circled the hole—it clearly goes into the bock, and it would need to since it is one of TWO bolt around the bottom radiator hose intake. The only bolt I know that ONLY goes into the timing cover and nothing else, is the top bolt.

I believe it is like the one you see at the end of my arrow—note—there is a void behind it. NONE of these bolts interfere with the timing chain as the void is to hte outside of the chain.

I will confirm all this and make sure i send pics.

At this point, Wednesday is my earliest to take care of all this—to get the harmonic balancer and timing cover off at least.

Today got the intermediate shaft on! Will update all this on the thread. Having some trouble putting the pitman and drag link on as a unit…may need to disassemble more linkage to get it to work.

Update: Because of various comments, i think the part I circled is the TOP of the bottom intake bolt—that goes into the block.

So, I think I am one hole off and that the bottom intake bolt does indeed go through the cover ONLY.

[Rembrant]

Here is a stripped down 351 C block. I have circled the hole—it clearly goes into the bock, and it would need to since it is one of TWO bolt around the bottom radiator hose intake. The only bolt I know that ONLY goes into the timing cover and nothing else, is the top bolt.

But that's not the same bolt that you pointed to in your original picture, is it?

 

[AmericanSavage]

Here is a 400 I found on the web. You might be able to guestimate where the bolt lives. To me it looks like it goes through the timing cover and into the block. https://forum.garysgaragemahal.com/file/n129536/FOR-LONG-6.jpg

Cover the front of your engine with saran wrap before you start drilling. Additionally a magnet taped to the outside of a plastic bag can catch all the metal shavings.

This matches with my brief look at the cover, and noticing there is a block behind that hole in particular.

GREAT idea on saran wrap and magnets!

Ordered the 5/16-18 heli coil today.

Some folks have suggested maybe there is a larger bolt in that one spot only. I am inclined to say, not in my case.

Here is Gary’s Diagrams—note the 351C/M 400, and 460) are the same. The part list notes that they are all 5/16-18 AS REQUIRED. Which means they are all the same size for those two engines:

https://www.garysgaragemahal.com/water-pump-s--illustrations.html

I add: I ran the tap through a couple of other holes, and it went smoothly, and had the same fit as the hole I am having tropuble with.

 

[AmericanSavage]

Here is a stripped down 351 C block. I have circled the hole—it clearly goes into the bock, and it would need to since it is one of TWO bolt around the bottom radiator hose intake. The only bolt I know that ONLY goes into the timing cover and nothing else, is the top bolt.

But that's not the same bolt that you pointed to in your original picture, is it?

UPDATE: I matched the gasket between the cover and the block….that hole on the block rests ABOVE the intake and the hole I circled. THAT throws me off a bit because I saw block behind that hole…or did I? Certainly here is a block on the hole above the intake. Pics coming.

[Rembrant]

Yes, it is.

Ahh, OK, my bad. I thought it was one of these two bottom bolts which look to be the ones that thread into the timing cover and not the block.

 

[85lebaront2]

Yes, it is.

Ahh, OK, my bad. I thought it was one of these two bottom bolts which look to be the ones that thread into the timing cover and not the block.

Those will definitely screw into only the timing cover, be it aluminum or steel. The only oddity I have run into, some of the Windsor engines have two thin head bolts the come in from the back holding the metal back plate on the water pump.

[ArdWrknTrk]

Here is a 400 I found on the web. You might be able to guestimate where the bolt lives. To me it looks like it goes through the timing cover and into the block. https://forum.garysgaragemahal.com/file/n129536/FOR-LONG-6.jpg

Cover the front of your engine with saran wrap before you start drilling. Additionally a magnet taped to the outside of a plastic bag can catch all the metal shavings.

This matches with my brief look at the cover, and noticing there is a block behind that hole in particular.

GREAT idea on saran wrap and magnets!

Ordered the 5/16-18 heli coil today.

Some folks have suggested maybe there is a larger bolt in that one spot only. I am inclined to say, not in my case.

Here is Gary’s Diagrams—note the 351C/M 400, and 460) are the same. The part list notes that they are all 5/16-18 AS REQUIRED. Which means they are all the same size for those two engines:

https://www.garysgaragemahal.com/water-pump-s--illustrations.html

I add: I ran the tap through a couple of other holes, and it went smoothly, and had the same fit as the hole I am having tropuble with.

All water pump bolts are the same thread, just different lengths.

That's why I like to make an outline and keep them in place as they come out.

I also apply anerobic PST on all my waterpump and timing case bolts to keep the threads from ever corroding.

(Yes, I know your 335 engine only has a steel plate and not the problematic mag/alu case of Windsors and 385's like mine)