[Chris65LeMans]

This is part of my ongoing project to upgrade to a CVF serpentine system.

As with many upgrades, I've run into more issues. (My Offy valve covers won't fit with the new alternator position, new valve covers will need some surgery to fit, etc)

A more serious issue is this bolt inside the red rectangle: (Ignore my finger in the blue glove.)



It goes through the water pump, timing cover, and into the block. I thought that CVF had sent me a bolt that was too long - it wouldn't go in all the way. Turns out that the bolt hole is completely stripped out. (I looked at the old bolt, and it seems to be clad with a lot of teflon - so it's an old problem.)

So - I need to re-thread this hole to proceed. I've never done that before, so is there anything I need to watch out for? Do I need to re-thread both the timing cover and the block?

Thanks for your help. I'm now off the deal with another emergency - a dead water heater.

[HWYSTR455]

The only threaded part of that bolt 'hole' is in the block, it passes thru the water pump and timing cover.

Sure it's not possible that bolt is too short? It's aftermarket, so it could be short. Or worse, there could be some of the old, original bolt snapped off in the block, making the hole 'shorter'.

Only way to do it right is to remove the timing cover, and access the hole directly. No way will you be able to tap that hole, or install any type of thread repair, with the timing cover in place.

I suggest removing the balancer, timing cover, and post a pic of the block where that bolt enters. Then a better assessment can be made.

Not a bad thing really, you can clean all that up and check surfaces, etc for damage.

.

[1969GiPper]

If it’s never been done or if it’s been a while this would be a good time to inspect the timing chain and gears while the timing cover is off.

[Schurkey]

Originally Posted by Chris65LeMans

This is part of my ongoing project to upgrade to a CVF serpentine system.

As with many upgrades, I've run into more issues. (My Offy valve covers won't fit with the new alternator position, new valve covers will need some surgery to fit, etc)

Tells me that CVF needs better engineers. Why would they design-in problems like this unless they were just plain careless or clueless?

Originally Posted by Chris65LeMans

I need to re-thread this hole to proceed. I've never done that before, so is there anything I need to watch out for? Do I need to re-thread both the timing cover and the block?

Good chance that a simple Heli-Coil-type repair insert will be perfectly adequate.

You might even get by with drilling and tapping for the next-larger diameter bolt, but then you'd have to drill the pump and cover to accept the larger bolt as well.

Any way you look at it, the best plan is total disassembly before drilling and tapping. It would be the rare person who could drill and tap the block without taking off the timing cover. (and I don't know where you'd get a tap that's long enough.)

[Skip Fix]

It is a common bolt to rust in place in the block and break off,part of why I use ARP SS bolts for those now. Drilling the hole perfectly straight and in the right spot for a helicoil with a piece of bolt in there is kind of tough.

[Dick Boneske]

On all Pontiac V8's until '69, the location you show used a stud with a nut, not a bolt to hold the top of the timing cover. You may find that the threads in the block are OK if you use a stud that's long enough. That's what I would try. Otherwise, you'll need to remove the timing cover and fix the threads with a Helicoil or threaded sleeve.

You should be removing the timing cover, anyhow, to check the chain. Pontiacs are noted to stretch timing chains. Failure to fix a stretched chain could cost bent valves or worse if the chain slips on the gears.

[HWYSTR455]

Originally Posted by Dick Boneske

On all Pontiac V8's until '69, the location you show used a stud with a nut, not a bolt to hold the top of the timing cover..

You're correct on the next lower position, though the one that is in question here is a bolt from the factory.

Yeah, I just looked to see if I had that info, the stud length, but couldn't find that.

Skip Fix - you have the thread & length info for that stud?

.

[Chris65LeMans]

Also - my block is a ‘69 out of a Firebird with a newer 11 bolt water pump/timing cover. I’ll pull off the timing cover and take a look. Thanks for all the help so far!

As for the bolt length question - the CVF bracket for the pulley system bolts onto the water pump after some spacers. That’s why the new bolt’s length is different than the ARP bolt it is replacing. It goes on with 3 bolts. This middle one is the only one that goes through to the block. The other 2 (much shorter - just screwing into the timing cover) bolted on fine.

[grandam1979]

So is the bolt broke off in the hole or is the hole stripped

[77 TRASHCAN]

Originally Posted by grandam1979

So is the bolt broke off in the hole or is the hole stripped

Sounds like it could be a combination of both. Until timing cover is off, we will not know.

There's a bolt on opposite side of timing cover, beware if it!!!

[chiphead]

That stripped hole can be heli-coiled in-car. 3/8"-16 thread is the correct bolt size. You just have to take the front accy system off and be careful during the drilling process. Heck I'd take the whole radiator and everything out so I could really get in there while I was drilling.

I would verify there is nothing broken off in the hole, and the hole was in fact stripped out. It's a blind hole in the front face of the block. It doesn't go into the water jacket. That boss should be thick enough to take a thread insert. Careful drilling with the special heli-coil bit will follow the old hole. Then use the special threader to thread the block for the insert. Twist insert just past flush and break installation tang. Viola, you're done.

It's common for those bolts to get rusty from coolant intrusion at the gasket. My '67 block had studs there. I had to heat the block/stud area with a propane torch and use Kroil and a pipe wrench to get them out.

[Skip Fix]

"It's common for those bolts to get rusty from coolant intrusion at the gasket. My '67 block had studs there. I had to heat the block/stud area with a propane torch and use Kroil and a pipe wrench to get them out. "

Yep that is how they get rusty.The stud in my one of my extra blocks was so locked in it just twisted off when I did that. Enough of it raised to where getting a straight shot to drill was difficult. A tall drill press or a Bridgeport would make it easier on a bare block.

ARP has stainless studs also.

[tooski]

I had two problems with my non-serpentine CVF setup. One was simple. The spacer placement in their instructions was wrong. Second, the bolt that you are questioning was too short in my kit.

[Chris65LeMans]

Originally Posted by tooski

I had two problems with my non-serpentine CVF setup. One was simple. The spacer placement in their instructions was wrong. Second, the bolt that you are questioning was too short in my kit.

Do you remember how much short it was? When I thought the bolt was too long, I had them send me a couple of shorter ones. I can call and ask for a longer one now. I found the belt is WAY too short. I asked them to send me their longest - it’s about 10 inches too short.

Edit - never mind. I see your kit isn’t mine. You probably are right that mine is too short, though.

[64speed]

So is the broken off bolt the fault of CVF or is it just an old corroded bolt

[Skip Fix]

Skip Fix - you have the thread & length info for that stud?
Pretty sure close to the stock one. It is in their complete bolt kit. I'll try and see they have specs in the sheet. I get the upper bolts in various lengths depending on is the alt bracket is under it or not.

[Old Goat 67]

What is the measurement from the front of the water pump to the block surface in this picture?

What length bolt do you have to go in there? Should be at least 3/8" to 1/2" longer, I would think. Measure the depth of the hole with a piece of wire to be sure.

[johnta1]

I think that bolt length is 3 7/8" long.

[Chief of the 60's]

Take a rat tail file or some other rigid small diameter rod, stick it in the hole and measure the length, Then go about 1/4" under that for your bolt length. Easy peasy

[johnta1]

And if it's less than about 3.5", there is probably something in there.



Or after marking where it is in the hole, lay it on the outside against the block to end of the pump to see how much would be sticking in the hole.