| Author | Message | ||
     Natexlh1000 |
I have a 1990 Toyota pickup and was trying to change out the plugs on its little 3.0. First friggin' one I tried was stuck in there. then the second and third. Beats me when they were changed last but it sure wasn't recently. I'm afraid of applying more force since I think the aluminum threads might just pop out! Lots of smart/experienced folks here, I was hoping for some advice. | ||
| Swampy |
Run the engine hot, then soak the plugs in PB Blaster, or something of that sort. Other than that, get out the Helicoil kit. | ||
| Coal400 |
Ouch... not a good situation. Kroil the hell out of them and let the vehicle sit over night. Try to get them out when the engine is cold (in the late morning). I have some other shaky suggestions but I don't want to be responsible for damaging your vehicle. I would give some other suggestions time before suggesting the minitorch. Definitely want to use that copper based anti-seize when you get those plugs out. They should sell the plugs with it already on there - if you ask me. I think the stuff runs for $6 at the local napa. If you end up busting one of those plugs in there, the head has to come off and its off to the machine shop. Good luck | ||
| Xb9ser |
Kroil is great stuff we use it at work.A friend of mine was takeing the bed off of a 1968 GMC truck and told me, I found this great stuff Kroil. He had sprayed the bolts the day before and they came right off.I told him I knew all about it it is great. It is the best I have used breaking something loose.Never tried PB blaster but have heard lots of good about it also.Eather one should work. | ||
| Mr_grumpy |
Give em a good blast around the base with a compressed air blowgun to clear any crap out first. Soak em with WD40 or whatever you got & when you take em out, use a sensible length bar or ratchet & first movement to tighten, just to break the seal, then wind em out gently 1/2 turn out 1/4 turn in, kinda like you were tapping a thread, & keep spraying em too. When you come to re-install +1 on the copper grease, I use it on any thread that doesn't need loctite. Alternatively, clean em up as best you can & sell the thing!  | ||
| Natexlh1000 |
Damn! Thanks for all of the ideas. The engine was still warm when I tried it last. I guess I'll try it cold next. | ||
| Bartimus |
Make sure you try the KROIL!!! | ||
| Swampy |
+1 on the back and forth tighten and loosen like using a tap, make sure you squirt your liquid of choice around the threads while you are doing that. | ||
| Just_ziptab |
Heat is usually your friend. The aluminum will expand more than the plug with heat from a torch. You may burn the valve cover gasket(not sure of your configuration there). Heat only the plug body,avoid heating the "area". The heat will "soak" into the head and expand it. IF you can get a 3/8 drive impact in there, try rattling the plug both directions. Use a good six point socket. Stop and let it cool and do the "heat cycle" again. Worse case, the head threads are going to tear on removal of the plugs simply because the threads on the plugs are rough with rust/corrosion/age. You will be very lucky if you can chase them. I had a K Wacker do that to me and a machine shop had a tool that drills and re threads in one pass for installation of a helicoil. I put a shop vac nozzle as close as I could to the work area and when the drilling was done, a scope showed no signs of chips in the cylinder. You also risk breaking the plug off flush. Once you start on this, figure that it's going to be down till it done cause your going to bust something............or keep driving it the way it is. | ||
| Ryker77 |
try soaking as instructed. If this is your only mode of transport have on hand a heli-core kit. It will repair the thread if they are damaged. | ||
| Coal400 |
Heat is not a good idea on aluminum threads. You have a much greater risk of stripping the softer aluminum threads if they are hot. There have been desperate measures that I've taken, but I'm reluctant to pass them on just yet. The risks are much greater than the reward. Be progressive in your approach. Kroil is the best stuff out there, but I did come across this product (http://www.crcindustries.com/marine/content/new.as px). I've never used CRC Freeze off, but if I were you I'd try it out. The claims make a lot of sense to me. It does pretty much the same thing as the torch but without the heat. I've also never healicoiled a plug, much less aluminum. I'd bring it to a machine shop to have it fixed - again if I were you. | ||
| Coal400 |
oh, and +1 on the "tap" action. | ||
| Sleez |
i have replaced a few threads in aluminum heads while still on the car. i pumped compressed air into the motor to blow the shavings out of the cylinder while tapping. i still have the kit in my toolbox, with about 5 inserts and the staking tool i believe. | ||
| Sleez |
taken from another site; http://www.georgiazclub.com/tips/ztech/sparkplug.h tm Aluminum Head Spark Plug Service -------------------------------------------------- ------------------------------ When performing a tune-up, any service or test on your Z-car that requires spark plug removal, avoid removing the spark plugs if the engine is hot. Try to wait until the engine cools down before proceeding with your service. The spark plugs are positioned in the cylinder head so that they are virtually surrounded by water jacketing. When you're running around town and the engine is operating at normal temperature, the coolant keeps the spark plugs and the cylinder head, in the spark plug area, at about the same temperature. After you've picked up that last part for the weekend tune-up and you've come home and shut the engine down, the aluminum head will cool more rapidly than the steel shell of the plug and, as a result, it will shrink around the threads of the plug and grip them more tightly. You are forewarned that if plug removal is attempted under this condition and sufficient force is applied to the wrench to break the plug loose, something has to give. Since the threads in the aluminum head are much softer than the threads of the steel shell of the plug, the threads in the head will stand a good chance of being torn out. And you know what this means. You have the options of either having the threads helicoiled, run without the spark plug or trash the head. Replacing the threads with a helicoil will probably work, but will you be comfortable knowing that the next time you remove the plug the repair may come out with the plug? Running on five cylinders, well, I don't think this would be good for gas mileage. And the last, a fashionable planter for some petunias? As a precaution you may try putting anti-seize compound on the spark plug threads before you install them in the head. A tube of this is available at any auto parts store. I've seen motor oil used but this is not recommended as the oil carbonizes from the heat generated by the engine and may make spark plug removal more difficult than having not put anything on the threads at all. | ||
| Sleez |
and another possible solution, the one i used was not a coil but more like the time-sert kit. http://www.popularmechanics.com/automotive/how_to/ 4212608.html Q: Yesterday I was driving home and a spark plug blew right out of the cylinder head. The car was towed to the shop where I'd had a tuneup the day before — which included changing the spark plugs. The mechanic said he could repair the threads, but my uncle says the cylinder head is ruined and the mechanic should replace it at his expense. The car has about 100,000 miles. Thoughts? A: There are a number of ways to repair stripped threads. In fact, it may be possible to simply chase the old threads with a tap and clean them up. Or, as illustrated, you can insert a Helicoil. There are several types of repair inserts, but we prefer Helicoils. I'd give your mechanic a shot at fixing the threads before I held his feet to the fire. When a spark plug has had a chance to marry a cylinder head for 100,000 miles, it's not uncommon for the aluminum threads to come out of the head with the plug. (I pull and inspect plugs every couple of years and reinstall them with a small dab of antiseize compound, but that's another column.) A proper thread repair should last as long as the life of the car. This type of repair can be used for almost any threaded fastener, by the way. And that includes cast-iron, steel and aluminum parts. Warning: Installing a Helicoil or other threaded insert looks simple — but it's not. Any readers out there who wish to attempt it might want to practice a couple of times on scrap parts. Start by threading the special Helicoil tap into the remaining threads in the head. This is to ensure the new threads are concentric and parallel with the originals. Continue threading the tap in to cut the new, oversize threads. To avoid getting aluminum chips in the cylinder when retapping the threads, you should coat the tap with grease. The chips will stick to the grease and come back out with the tap. Back out the chip-laden tap, and clean up any remaining chips. I've also filled the cylinder (before tapping the hole) with oil-soaked clothesline to catch any chips — but that was in a racing engine with a squish band only a few thousandths of an inch deep. Street engines with a more normal compression ratio should be fine if you are careful, and blow the chips out with compressed air. Mostly, you don't want any chips to find their way out the exhaust port and wind up in the catalytic converter. Now you can thread the appropriate-length coil over the installation mandrel. There's a raised flat on the mandrel that will catch on the tang in the coil, allowing you to thread the coil into your new threads. The coil is a little bit bigger than the threads, which will keep it in place when you're finished. The tang will pull the coil into place from the inner end. Once the coil is in place, remove the mandrel. Now, use a pair of needle-nose pliers to break the tang off. It's prescored to break off cleanly and easily. Do NOT drop the tang into the cylinder! A few aluminum chips will not damage your engine, but a 1/2-in.-long piece of sharp stainless steel wire will tattoo the top of your piston and the combustion chamber before it finally gets out past the exhaust valve. | ||
| Sleez |
more info; http://www.fulltorque.com/sparkpluginserts.htm | ||
| Sleez |
here is the time-sert page; http://www.timesert.com/html/sparkplug.html hope all goes well. | ||
| Coal400 |
Sleez Interesting information on the helicoil repairs. Just curious, for future reference, how did you pressurize the cylinder with compressed air? I've heard of being able to do valve spring preload while keeping the heads on. By putting a nipple in the spark plug hole and compressing air in the cylinder(to hold the valves closed while you work), but in this case you have a spark plug seized in that hole. If you put a nipple in the MAP sensor bung, all the air would escape from other cylinders with valves opened. Did your motor have multiple plugs per cylinder? You must have a 250 Gal compressor. My little 25 would not have enough ballz to keep up. | ||
| Sleez |
i pressurized the intake, and turned the motor so the least number of valves were open, (chrysler 2.2 IIRC)and it was a huge compressor at work, don't know the size. just need a little breeze to keep the chips blowing outward, and had the flutes greased up pretty good as well. | ||
| Coal400 |
Good tip as well... Crisco actually makes for very good cutting oil (for drilling) - just another tip. | ||
| Coal400 |
Crisco shortening that is... | ||
| Just_ziptab |
Every case is different it seems, when dealing with seized or broken bolts. Heat up an exhaust manifold Y pipe nut that is stuck on the stud, to cherry red and throw a cup of cold water on it. Usually comes off freely. Just tonight, I had a very small broken stud(flush of course)in my chainsaw(aluminum) handle bracket. I could wiggle it with a pick, but tapping on the pick wouldn't spin it. Gave it a shot of WD-40 and is spun right out. Patience is the key. Experience helps too. | ||
| Swampy |
+1 on the Patience thing Frustration occurs when something that is supposed to happen doesn't when the proper influence is placed upon it. When the beginnings of fustration are felt, thats time to back away and resize up the situation. | ||
| Natexlh1000 |
Thanks for all of the advice. I tried it one more time and it was the same. I think those plugs are good for the life of the engine. In fact, I feel that they will DEFINE the life of the engine! | ||
| Mr_grumpy |
Sounds like my kind of plan!  | ||
| Coal400 |
Mini torch the steel portion of the plug - get it to where it just starts to turn red. get a damp (not wet) rag put on the metal part of the plug "shocks" it. - You risk breaking the insulator from the shock and putting pieces of ceramic into your cylinder - You risk stripping out your threads on the head when you try to remove it hot. This has worked after trying many other things; where my friend and I were about to pull the head any way. I would have had a hard time doing this to my own vehicle, but thankfully I never had to. 1 vehicle this method did not work on was the original Dodge Caravan. The plug's threads actually protruded into the combustion chamber allowing carbon deposits to get onto the first few threads - you will never get these plugs out without removing the head. | ||
| Dapope |
NO HEAT! | ||
| Starter |
+1 No HEAT! If it were mine I would take it to a good engineering shop and ask them to remove the plugs for you making them aware of the issues. Either that or a good mechanic who will be able to insert any stuffed threads whilst doing the job. CRC Freeze may work but I doubt it cause the seal will be so damn good nothing will wick its way between the head and plug. Other than this get some courage up, hold your breath, twist and wait for them to "crack" free. Thats how I got 2 outta a GSXR head incident free. |
