Blew out #2 spark plug, thread repair

[sb001]

Driving a few days ago the #2 spark plug blew out of the cylinder head when I went to go from a light. Car still ran on 3 cylinders so I was able to limp it back home.
I tried futilely for a couple hours yesterday to thread the plug back in, it simply will not catch so I am sure the threads in the head are damaged.
I bought a spark plug thread repair kit from autozone, that has basically a two-part combo tap that has the 14mm tapping threads at the front, and then larger (16mm I think, not sure) threads farther back on the tap to enlarge the hole for the insert. here is the kit I bought:

https://www.autozone.com/test-scan-and-specialty-t...141511_0_0

Due to this design, it appears the front of the tap will have to enter the combustion chamber as I am tapping. Is there any risk of me hitting the piston as I am tapping? thx

BTW, the reason I don't just simply drop the engine is because I am currently temporarily residing in an apartment until I close on new house in a few weeks, so i don't have a garage to do the work (apartment will not let me work on the car in the parking lot) and I really need this driveable. Thx
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I'm the humblest guy on this board.

1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor

[raydog]

Not if you take the piston off of TDC. Just position the piston slightly lower on its power stroke.
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Come on, It's not rocket science. KISS

[Cusser]

[sb001]

Thanks all,
Cusser I actually have a Timesert set I got on clearance from aircooled.net a couple months back when my oil pressure switch threads stripped out. But it's only for that size thread. I agree Timeserts are the best, but I figure if this will get me by until I get into the new house and am able to drop the engine later down the line that will work OK.
I was going to use Loctite myself on the insert, but the instructions for this kit actually say to apply high-temp RTV sealant to the outside of the insert instead. I suppose either would work.
_________________
I'm the humblest guy on this board.

1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor

[Starbucket]

Put grease on tap threads to catch the chips then clean off with alcohol.

[sb001]

[Cusser]

[sb001]

OK got the insert installed and the spark plug in- everything seems good, but Cusser I tried to torque it to 25 ft/lbs and it just never wanted to get there, I was afraid keeping trying to tighten it my be threading the insert into the chamber so I left it as is. Seems tight though so I think it will be fine.
Only other issue I just noticed when I went to reattach the plug wire is that it apparently blew off part of the connector that slides onto the plug, so now the plug wire won't reattach. I have seen though that some vendors sell just the plug-end connector by itself, so I will order one of those and then hopefully I will be good to go.
_________________
I'm the humblest guy on this board.

1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor

[Starbucket]

Turn the motor over by hand first to make sure the insert didn't thread into the chamber and hit the piston. Look around the engine compartment for the plug wire end and you might find it, just use a bright flashlight.

[Cusser]

[sb001]

[viiking]

[Charitha]

Guys
I'm doing top end rebuild on my 1600 super bug. heads are out, so best time to repair the stripped spark plug holes.
I have got a set of Empi spark plug inserts. Can someone please tell me what basic tools are needs and what steps to take installing these.
One thing i noticed was that when the insert is screwed on to the plug, end of the insert is not flush with end of the spark plug thread. So the spark plug sits maybe like 1-2mm inside the thread insert. would this cause issues with combustion?

[67rustavenger]

Clean up the combustion chambers before attempting yo fix the stripped sparkplug threads.
In this pic. It appears to be a crack from the valve seat to the sparkplug hole.
Look at the 2- 2:30 position in the image. It looks like a crack.

Sparkplug hole to valve seat cracks = junk head.
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I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!

There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo!

[Baccabug]

I used the same type of insert (Link below) on my engine, and did the greased tap technique to "capture" the shavings, I pulled off the head was shocked to see all the shavings. Glad I did so I could clean it out.

I thought the repair worked well, time will tell how long it lasts. Also used high temp rtv on the insert threads per instructions.

https://www.amazon.com/dp/B0002SRF4O?psc=1&ref=ppx_yo2_dt_b_product_details

[Cusser]

For solid threaded inserts, see my update post made today at this thread https://www.thesamba.com/vw/forum/viewtopic.php?p=9796819#9796819

However, in your instance the cylinder head is already off, so in your shoes I'd have a VW machine shop repair professionally, even if you need to send the cylinder head away for this. It looks to me as well that you may have a crack near the thread area.
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[Starbucket]

I would look for new heads, Pic. #4 looks like the valve seat has cracked (Raised piece of seat, valve on left) so rebuilding them will cost as much or more than new heads.

[Charitha]

Yes i did see the the surface cracks on the two heads when i pulled them out and is actually a concern. This is going to be a standard rebuild with 85.5 pistons and no mods. hoping to use just for bit of weekend cruising. i understand the crack will only get worse overtime..maybe loose some compression. before pulling the engine out, i did a compression test and they ran around around 100psi.
sorry for my ignorance on this subject, but i do appreciate if someone could explain what kind of catastrophic failure can be expected with the cracked heads
also does anyone have any thoughts on the solid insert gap? tnx

[Starbucket]

After you install it with the head off you could grind it flush, but for your stock rebuild I don't think you would notice any difference ground or not, remember the gas vapor is compressed to a small space with the plug in it so it's going to fire the gas vapor.

[Cusser]