Spark plug thread inserts., Should I be concerned? |
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Spark plug thread inserts., Should I be concerned? |
Erben914 |
May 13 2014, 11:15 PM
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#1
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
I have my engine out for a bear tub restoration. I am reassembling everything and almost ready to put the engine back in.
As I was cleaning things up replacing the tube seals and getting ready to adjust the valves I found these threaded sleeves in my spark plug holes. Looks like a PO was a DA? Did they strip all of the spark plug threads and use threaded inserts? I probably wouldn't have even noticed but they are loose and partially back out when I took out the plugs. They are at different depths now but do they bottom out when the plug is tight? I can't tell because the base of the plug covers the sleeve when the plugs are in place. I really don't want to take the heads off. I had no issues prior. If it ain't broke don't fix it? Or am I risking a bigger problem? |
Hawker |
May 13 2014, 11:24 PM
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#2
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Newbie Group: Members Posts: 10 Joined: 11-February 14 From: Santa ynez Member No.: 16,988 Region Association: None |
Well I'd say you just might be on to something their . It very well could be a much bigger issue if left . Just my thought ! Not to mention I ran it that issue and learned some valuable wisdom .
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Erben914 |
May 13 2014, 11:33 PM
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#3
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
Well I'd say you just might be on to something their . It very well could be a much bigger issue if left . Just my thought ! Not to mention I ran it that issue and learned some valuable wisdom . We'll spill it! Enlighten me. (IMG:style_emoticons/default/pray.gif) |
infraredcalvin |
May 14 2014, 12:10 AM
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#4
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Distracted Member Group: Members Posts: 1,575 Joined: 25-August 08 From: Ladera Ranch, CA Member No.: 9,463 Region Association: Southern California |
If they're loose, there is a problem, pay now or pay more later. Try removing the insert to see why they're loose, a good machine shop will be able to weld and tap new threads, also a good time to have them check valves/seats...
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Mblizzard |
May 14 2014, 05:34 AM
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#5
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
I had a car with the inserts and never had an issue for a number of years. But when we pulled the engine for a rebuild the thought was to fix it correctly. So when we pulled the heads we found a series of cracks around the plug openings. Don't know if the cracks were there first or if the inserts caused the cracks. However the cracks were eventually going to cause a problem. So I think it is worth pulling the heads to be sure they were done right and that there are no cracks. Easier now than having to pull the engine again.
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Joe Ricard |
May 14 2014, 05:49 AM
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#6
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Time big insert. I had them in several HI Preformance type IV's It's no big deal unless they are loose.
For a time Aircooled heaven was doing this on new heads to prevent other issues and use a smaller plug to give more meat between the valve and plug. Those are not Heli-coil but time certs . So back down off the cliff and leave it alone. |
Cap'n Krusty |
May 14 2014, 08:52 AM
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#7
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
I disagree, Joe. If they're loose, they're toast. Off with the heads! They MUST be replaced. By design, Time Serts lock into place, and if they're not locked in position they're a disaster waiting to happen. Odds are there are cracks in the area around the plug holes and the inserts have come loose.
Don't let bad news become a tragedy! The Cap'n |
JStroud |
May 14 2014, 09:02 AM
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#8
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Senior Member Group: Members Posts: 1,463 Joined: 15-January 11 From: Galt, California Member No.: 12,594 Region Association: Northern California |
Eric, HP machine in Victor(Lodi), has done my machine work for years, Harry did all the machine work for my 2056. I'll find his contact info for you.
Jeff |
Hawker |
May 14 2014, 09:14 AM
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#9
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Newbie Group: Members Posts: 10 Joined: 11-February 14 From: Santa ynez Member No.: 16,988 Region Association: None |
Well I'd say you just might be on to something their . It very well could be a much bigger issue if left . Just my thought ! Not to mention I ran it that issue and learned some valuable wisdom . We'll spill it! Enlighten me. (IMG:style_emoticons/default/pray.gif) Listen to the captain / crunch ! These heads are casted some have micro crack flaws , some don't ! Mine did & I could of lost my motor lucky for me we just needed to replace the heads if not caught in time it could have lost all to fire ! Are you in to taking chances ? These's other threads who say don't worry probably have heads with out flaws but if they did I'm sure they would be singing a different tune ! Wisdom is what one learns, ignorance is expensive (IMG:style_emoticons/default/shades.gif) (IMG:style_emoticons/default/hissyfit.gif) (IMG:style_emoticons/default/av-943.gif) |
JStroud |
May 14 2014, 11:36 AM
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#10
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Senior Member Group: Members Posts: 1,463 Joined: 15-January 11 From: Galt, California Member No.: 12,594 Region Association: Northern California |
Here you go, HP Engine and Machine
17327 N Bruella Rd Victor CA 95253 209-368-8355, Harry is the owner. Good luck, Jeff |
Cap'n Krusty |
May 14 2014, 11:45 AM
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#11
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
BTW, loose plugs, even plugs tight in loose inserts, can cause the exhaust gasses to torch right through the gap provided by their being loose. That's not something you want to have happen to your engine.
The Cap'n |
Erben914 |
May 14 2014, 07:18 PM
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#12
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
Thanks for all the input guys.
I guess I won't be putting the motor back in this weekend. (IMG:style_emoticons/default/mad.gif) I will pull the heads and post some pictures for further advise. I will probably be calling Jeff's machinist soon. Thanks Jeff. And the resto was going so well too. |
Mblizzard |
May 14 2014, 07:26 PM
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#13
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Thanks for all the input guys. I guess I won't be putting the motor back in this weekend. (IMG:style_emoticons/default/mad.gif) I will pull the heads and post some pictures for further advise. I will probably be calling Jeff's machinist soon. Thanks Jeff. And the resto was going so well too. Damn! That looks nice! Great work. |
JStroud |
May 14 2014, 07:40 PM
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#14
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Senior Member Group: Members Posts: 1,463 Joined: 15-January 11 From: Galt, California Member No.: 12,594 Region Association: Northern California |
Damn Eric that's looking awesome, not bad for a garage paint job (IMG:style_emoticons/default/poke.gif)
Guess you'll just have to put more together while waiting for the motor. Really starting to come together, can't wait to see it. |
Erben914 |
May 14 2014, 07:49 PM
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#15
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
Thanks.
I pulled it apart in November and was trying to make the wcr this weekend. I didn't quite make it. I stripped it to bare metal, repaired a few bad rust areas and painted it in my garage It is coming together better than I expected. (IMG:style_emoticons/default/piratenanner.gif) |
Erben914 |
May 14 2014, 07:59 PM
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#16
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
[quote name='JStroud' date='May 14 2014, 06:40 PM' post='2037585']
Damn Eric that's looking awesome, not bad for a garage paint job (IMG:style_emoticons/default/poke.gif) Guess you'll just have to put more together while waiting for the motor. Really starting to come together, can't wait to see it. [/ Thanks. It was a lot of work. My neighbor wants me to paint his car now. |
Erben914 |
May 14 2014, 08:06 PM
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#17
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
Hey any tips on pulling the head? I know to keep the push rods in order. Anything I need to mark or take a picture of before I go at it??
Sorry to be such a rookie. This is uncharted territory for me. |
jmill |
May 14 2014, 08:14 PM
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#18
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
Had a single port VW motor overheat on me. Heads got hot, expanded, and blew all four plugs out. Tore up all the plug threads. I time certed them and built up a new engine in the meantime. Losing a belt or heater hose does it. If you got it apart fix it right.
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Mblizzard |
May 14 2014, 08:20 PM
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#19
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Hey any tips on pulling the head? I know to keep the push rods in order. Anything I need to mark or take a picture of before I go at it?? Sorry to be such a rookie. This is uncharted territory for me. Make sure when you put it back together you get the push tube retaining springs in correctly. Had to check and redo mine a couple of times to be sure they were right. Check your valve guides if they go to the shop, just plan on replacing them. Inspect your exhaust studs carefully. Use the good Viton oil tube seals. And take the heat shield off the bottom side of the head before trying to pull it off. Makes it much easier! (IMG:style_emoticons/default/headbang.gif) Plan on replacing all of the cheese head tin screws with stainless steel hex head ones. Use anti seize on everything! |
Erben914 |
May 14 2014, 10:08 PM
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#20
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Member Group: Members Posts: 137 Joined: 1-January 13 From: Sacramento Member No.: 15,314 Region Association: Central California |
Thanks for the advice.
Here is what I found. Do you see anything else wrong here? I will clean them up and inspect further. One combustion chamber has a lot more carbon/soot. Should I pull the cylinders? Should I think about new rings? This has been apart before. The cylinders are numbered with a sharpie. Any |
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