Hot Rods Anyone used a Keen Sert in a SBC block?

I have a 327 block I am pondering getting some machine work done on. I spend a ton of time taking the flash off the block etc and then I noticed that maybe a half dozen bolt holes have threads that are eaten away from corrosion.

Of course I couldn't have found this early on....
So, I am looking at putting Keenserts in for a pretty permanent fix. How much meat is around the head bolt points close to the water jacket? It would be a 9/16-12 outside thread with a 7/16-14 inside thread. It takes a 33/64 drill bit I believe.

Thanks

 

Root,
I would have to have a block to look at but I'll bet that there is enough meat to use one. Let me make a call right quick and get back with you in the event that someone else doesn't answer it for you.

 

Thanks Bro.

 

I put a couple into a 409 block years back.
Just make a tool to make sure you are drilling and tapping straight int o the material.

Mike

 

I prefer time-serts, eliminates having to drive the pins in

 

I'm only guessing, but wouldn't the deck be a solid piece "X" thick? The threads would be in the deck and the cylinder below. The cylinder being the part that might shift and be thin if cut too big.

 

I figured I would make something that referenced the deck surface for my drill guide.

 

Root,
Just got off the phone with the schoolster. He reminded me of a 350 block that we repaired a couple of head bolt holes, he thinks that the keen serts are not a good idea. He said drill and tap the holes 5/8 then screw 5/8 bolts in the holes and cut them off even with the block and drill and tap the plugs the proper size and thread for the head bolts.

Red Loctite will keep the plugs from ever backing out, use it with the Loctite solvent. Then rent a magnet drill if you can't borrow one and use it to drill for your new head bolt holes. That will keep everything copacetic for you.

Anyway that is how we did the 350 back in the 90s. I'd offer to do it for you but you are as good at this stuff as I am if not better, well that and your missus doesn't want to have to put up with me for the weekend.

No matter what you do good luck to you.

 

Thanks. I have another block. I just hate it that I wasted all that time.

 

I have repaired headbolt holes in chevy blocks with an insert I got from Fastenal. I forget what they called it but it is essentially a premade version of what you do by using a bolt.They are nice and thick plus use a standard tap. Juss thot Id pass on the info...

 

I have repaired headbolt holes in chevy blocks with an insert I got from Fastenal. I forget what they called it but it is essentially a premade version of what you do by using a bolt.They are nice and thick plus use a standard tap. Juss thot Id pass on the info...

 

You haven't wasted all that time, relay the block to me, I'll fix it then you'll have a spare.

 

Everybody on here seems to be down on Helicoils. I have used them for thirty years and more with no problems, from head bolts on tractors down to thermostat housing bolts, and yes, SBC head bolts, too.

 

Keenserts are a fine way to go,used two on the front acc. holes on a 327 , just used a drill guide,tapping block and studded the holes,use them every day at the shop I work at, much better than heli coils but we are constantly r and r ing the bolts so heli coils were not a good choice, for head bolts that would be good I think if it were studded.We only have a failure with Keenserts when the holes are drilled oversize.

 

those are E-Z Loks
http://www.afi.cc/contentonly.aspx?file=images/vendors/EZLOK.pdf

 

Hey check your messages I might want to trade some stuff with you or something.

 

Thanks guys. I guess I'll look at the block and see which ones exactly are bad and the qty. I'm not anti heli coils, but I just thought these might be a little more substantial. I even thought about putting them in wet and using studs to minimize disturbing them.

 

I used Helicoils to repair at least half of the headbolt holes in a DZ 302 block. That was about 15 years ago and I still see the car being driven every now and then with the same motor.

 

First the Keene-certs and the knock offs are great.... way better than helicoils. Second you could probably use studs with locktite, lastly you can just tap oversize and use larger studs. There are even studs that have two different diameters i.e 1/2" in the block and 7/16' on the head side.

 

How hard is it to tap cast iron?

I even thought about installing the studs with some sort of loctite permanently. The threads aren't completely gone, it just looks like they had water sitting in the block in the salvage yard etc. No getting a warm fuzzy, just running in the bolts and forgetting about it.

 

The cast iron that I have tapped has seemed pretty soft, no problems with the tapping.

Sometimes the initial drilling can be hard to start, but you are already a step ahead on that front.

 

Found this in the archives.
http://www.jalopyjournal.com/forum/...hreaded-insert-in-block-for-head-bolt.804630/

 

Its so soft you don't even need any type of tapping fluid, detroit wonder metal.

 

YES, a "drill guide" of some sort's crucial!

 

Very easy. Pretty much self lubricating of sorts too

 

I would be scared to drill 5/8 holes in the deck. I would think it'd compromise the bore. Here's a 5/8 wrench around those bolt holes for reference, AND to use the supposed 5/8 bolts you'd be drilling/tapping even bigger holes than 5/8!! YIKES

 

The mere action of head bolts going in and pulling against fresh threads...
validates the existence of head stud kits.
I used head stud kits from Crankshaft Co. when I had the shop...Never a problem.
The stud is set, never to turn again...Only its tension pulls on the new 'fix'.
Works with Helicoils, but we used steel thinwall 'nut-serts'. (back in early 1980s)

 

Groucho, it's not a 5/8" hole. The OD is a 9/16-12 thread and the
inside is a 7/16-14. That would equate to about .062" off each side, if my ciphering is correct.

EDIT# I see what you are talking about now. I missed the quote.