Blown out plug with a twist

[98EXPY 5-0]

Last week i got towed home after i blew out the number 1 plug. As it turns out, it must have already been fixed before. The thread insert came out with the plug. Before i realized that part, i had bought an insert kit (not a helicoil).
The plan was to see if the blown out insert would thread back in, to ***** the threads in the head. Then i was going to put in a new insert. Well it threaded in with no trouble. However, the external threads on the two inserts dont match up. I figured if i used the included tap, it would weaken the threads. Also the blown out insert didnt have any signs of threadlocker. So i took the chance and put a new plug in the old insert with anti sieze, and used red loctite on the insert.

If this one blows out again, ill have to find an oversized insert or replace the head i guess.

 

[panda24619]

those are your only options. but if i were you. just junk the 4.6 and get a 5.4. haha

 

[Thermo]

98Expy5-0, if you blow out the plug again, let me know. I have the kit to fix your head. All you have to do is buy the insert ($12 plus S&H), and pay for the shipping to and from my place (normally about $15 each way). The kit is easy to use and you can do #1 plug in about an hour. If you are interested, let me know.

 

[98EXPY 5-0]

98Expy5-0, if you blow out the plug again, let me know. I have the kit to fix your head. All you have to do is buy the insert ($12 plus S&H), and pay for the shipping to and from my place (normally about $15 each way). The kit is easy to use and you can do #1 plug in about an hour. If you are interested, let me know.

I appreciate the offer. Do you have the coveted Timesert kit or another? My concern now is that it's already been drilled out for an insert, so any insert I try to use would have to be larger in diameter. I'm not sure which insert I already have in there. Like I said, it came that way and it's the same one that blew out. I'll post a pic, perhaps someone will recognize it.

My other concern is that it's not exactly a roadside repair, so if I start driving it again, and it blows, I have to get it towed again. I thought I read somewhere that if I disconnect the fuel injector on that cylinder, I can limp it home on 7 cylinders? Is there any truth to that?

 

[Thermo]

98Expy, yes I have the Timersert kit. Based on the sleeve that you have, if that blew out, whoever did the original sleeve did it wrong. In that case, odds are, you are looking at another head to fix your issue. I hate to be the messenger, but that is the short of the story. That sleeve is roughly the same size as what the Timesert sleeves are. So, getting the Timesert kit sent to you to fix your current head really is not an option. Granted, looking at it, I do not see any locking compound on the sleeve. So, right there is part of the issue. Another thing is that the sleeve should have been expanded on the end to prevent it from sliding out too. That is what the Timesert kit does to prevent future issues.

 

[98EXPY 5-0]

I don't think it "blew out" as much as unscrewed. I had occasionally been hearing that faint exhaust leak sound, but didn't realize it was associated with this. My 98 Expy had the broken stud leak since new, so when I kept hearing the faint one from this motor, I thought I was imagining it. It wasn't constant and I would mainly hear it when I first started it.

I screwed the insert back in without any force (just the extension, no ratchet) and it threaded right in. I assumed that if the threads were messed up, it wouldn't have gone in so easy. So hopefully that plus the red loctite will keep it in there. If not, I'll cross that bridge when I come to it. I was looking at blownsparkplug.com and that seems like a descent deal if you are local, but to pay to fly them out gets a bit salty.

I appreciate all the advice.

Tonight I am going to put it through the paces around the neighborhood and then check and see if it's still torqued in there. If it's not loose, I'll operate under the assumption that it's ok until something happens. Thats about all I can do right now.

Should I wait until it cools off to check it for tightness? Or perhaps give it an extra crank while it's still hot from driving to lock it in further while it's expanded? My only concern there is I would be breaking the loctite bond.

 

[Thermo]

98Expy5-0, I would say to check it while the motor is cold. You do not want to be inducing any more stress into the threads of the head by tightening the insert with the motor hot. Remember that metals expand at different rates and since the sleeve is not made of aluminum, it is going to expand differently.