When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My 1989 f350 7.3 IDI has been a decent truck so far, but I wanted to pull the glow plugs to check compression since I have the notorious thumping through the intake. Was able to pull 7 of them really easy, but the last one (right next to the brake booster) is completely corroded and has no hope of a normal socket ever even thinking about biting. What can I do to get this joker out?
You should be able to get a set of vice grips on it really, really tight and then you can use another set, or just a pair of pliers to turn the vice grips.
Another trick is to use the next size down socket, SAE or metric whichever seems best and tap it on with a hammer, then spin it out with a ratchet.
Either way, heat it up first if you can, or soak it with penetrating lube if you can't and then gently turn it back and forth until it breaks free and then just let it set for the lube to soak down the threads and then spin it out.
You should be able to get a set of vice grips on it really, really tight and then you can use another set, or just a pair of pliers to turn the vice grips.
Another trick is to use the next size down socket, SAE or metric whichever seems best and tap it on with a hammer, then spin it out with a ratchet.
Either way, heat it up first if you can, or soak it with penetrating lube if you can't and then gently turn it back and forth until it breaks free and then just let it set for the lube to soak down the threads and then spin it out.
I’ve already tried the next step down socket trick, it doesn’t help that the hex portion is completely missing. The socket wouldn’t go down far at all and would keep slipping off as soon as I tried turning it. Only the electrode is sticking out. I’ll try heating it up and some vice grips when I get home tonight.
The small Vise Grips I bought at Tractor Supply, genuine Vise Grip brand, have an Allen socket in the back of the adjusting ****. That's bailed me out twice now because I could get those little suckers super tight with a good quality, proper fitting Allen wrench. Got a corroded brake line nut loose on a Mercedes and saved the entire line (cut and put new nut, flare), they aren't cheap...
Got a grade 8 bolt out another time and the head was pretty hard steel.
Just use brand new Vise Grips and tighten them as tight as possible so the teeth are sharp and can dig in. Heat, of course as well. Not too much heat on the plug or it'll get soft and twist off in the head!
Or....maybe drive a good quality, too small, deep socket on with a hammer, I got some messed up lug nuts off that way.
Maybe a Torx socket?
Thanks for all the ideas, but I’m gonna have to pull the heads off anyways to do some valve work based on the compression numbers I found on the other 7 cylinders. I’m just gonna run it as is until this fall/winter and have a decent little project. My compression was half or below half of the average on two cylinders, one on each side.
here are the numbers for those who are interested:
1: 500
2: 310
3: 420
4: 440
5: 210
6: 425
7: 435
8: n/a?
and the cylinder numbers are based on the actual firing order (odds on passenger side and evens in driver side). Only started into this because of the notorious thumping, but definitely glad to know what’s going on finally. Also thankful to have the tools and knowledge on how to go about this now.
Those compression numbers are suspect. Which compression tester did you use? Are you going to remove the engine, or try to get the heads off with the short block in place?
Those compression numbers are suspect. Which compression tester did you use? Are you going to remove the engine, or try to get the heads off with the short block in place?
Didn’t even realize you posted until now. I used the Maddox diesel compression tester from harbor freight for those numbers. The numbers were initially worse than this before I found out one of the fittings on the hose was coming loose causing compression to leak before getting to the gauge. Fixed that and got these numbers. Plan (for now) is to do the work by only pulling heads using an engine hoist since the heads are so heavy. Plans got set back a little but still runs and drives great so I’m in no rush. Starts almost as easy as my little Hyundai that I daily.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
