5 Star Rising Posted March 19, 2021 Share Posted March 19, 2021 (edited) Have my motor out of my early 71 240z. Wanted to change the water pump and like always running into some kind road block. This time it's the bottom water pump bolt .All the other bolts came out except for this stubborn bastard. After breaking countless bolts on this car in different parts like panels you get the feel for when a bolt is going to break. I immediately stopped and tried a few things like heating the bolt up carefully with a torch because it's a super long bolt that disappears into the aluminum timing cover and goes into the block and penetrating oil was not going to reach that far. After heating the bolt and slowly turning it the bolt is miraculously almost out but I started celebrating too soon. The bolt will not come all the way out. I cut off the water pump tab with a die grinder and got it out of the way, been loading it down with WD40 and even Marvel mystery oil, tried prying it out with a claw hammer, a flat pry bar, used visegrips on the bolt and tried tapping the vise grips outward and this sucker is stuck, it will how ever spin around but there is tension on it. Speaking of tension does this bolt go through the timing chain tensioner? What the hell is keeping it from coming out? Now the bolt is a little bent and starting to get chowed up from me putting vise grips on it and messing with it. What do you guys think is keeping the bolt from coming out and what do you recommend I do? Really dont want to pull the timing cover if I dont have to and brake the oil pan seal and above head gasket seal. I gave up tonight, soaked it with more Marvel mystery oil. Maybe tomorrow will be a better day..This sucks. Edited March 19, 2021 by 5 Star Rising Quote Link to comment Share on other sites More sharing options...
jonbill Posted March 19, 2021 Share Posted March 19, 2021 It must be just crud build up on the bolt. Is it turning easily, but just not coming out of the hole? I'd be seeing can get a pry bar levering it gently out while spinning it with the impact gun. Quote Link to comment Share on other sites More sharing options...
5 Star Rising Posted March 19, 2021 Author Share Posted March 19, 2021 6 hours ago, jonbill said: It must be just crud build up on the bolt. Is it turning easily, but just not coming out of the hole? I'd be seeing can get a pry bar levering it gently out while spinning it with the impact gun. I wouldn't say it turns easily but it does turn all the way around. I saw some pictures online of the other side of that cover because I couldn't remember what it looked like. Looks like it just goes through that deep channel hole in the cover and then into the block. It's like its stuck in the cover. I'm pretty sure it's out of the block threads because if you compare the length of the other large bolt that did come out, it unscrews from the block at a certain point and the bolt that is stuck seems to be about 1/4" farther out than that point assuming they are the same length bolts. Quote Link to comment Share on other sites More sharing options...
grannyknot Posted March 19, 2021 Share Posted March 19, 2021 Your turning it back in then out right? That's best way to break up rust, screw it back in almost all the way, squirt your penetrating fluid down the hole, back it out again. I may take a dozen times of back and forth, you can also alternate with heat and quenching with penetrating fluid. That is probably the worst bolt to remove at the front of the engine, you're probably the first person to do it since the assembly line. Quote Link to comment Share on other sites More sharing options...
5 Star Rising Posted March 19, 2021 Author Share Posted March 19, 2021 2 hours ago, grannyknot said: Your turning it back in then out right? That's best way to break up rust, screw it back in almost all the way, squirt your penetrating fluid down the hole, back it out again. I may take a dozen times of back and forth, you can also alternate with heat and quenching with penetrating fluid. That is probably the worst bolt to remove at the front of the engine, you're probably the first person to do it since the assembly line. I have been scared to push it back in because I think its away from the threads in the block and only stuck in the cover but may have to try that. I feel like it could break at any moment. I'm so close haha.. It may be the original water pump, says ASUGI or something like that on it. It wasn't leaking but figured since I have the motor out it might be a good idea to change it, what a brave and dumb soul I am for attempting this. I hear alot of broken bolt stories about this. Well just got home from work, I'm going to have another go at it. Quote Link to comment Share on other sites More sharing options...
5 Star Rising Posted March 20, 2021 Author Share Posted March 20, 2021 2 hours ago, grannyknot said: Your turning it back in then out right? That's best way to break up rust, screw it back in almost all the way, squirt your penetrating fluid down the hole, back it out again. I may take a dozen times of back and forth, you can also alternate with heat and quenching with penetrating fluid. That is probably the worst bolt to remove at the front of the engine, you're probably the first person to do it since the assembly line. I have been scared to push it back in because I think its away from the threads in the block and only stuck in the cover but may have to try that. I feel like it could break at any moment. I'm so close haha.. It may be the original water pump, says ASUGI or something like that on it. It wasn't leaking but figured since I have the motor out it might be a good idea to change it, what a brave and dumb soul I am for attempting this. I hear alot of broken bolt stories about this. Well just got home from work, I'm going to have another go at it. Quote Link to comment Share on other sites More sharing options...
5 Star Rising Posted March 20, 2021 Author Share Posted March 20, 2021 Success! Tapped her in a bit tried the prybar and turn deal but didnt seem to work. Used a bunch of WD40 while vise grips were on the bolt and kept spinning it back and forth and pulling out at the same time.. finally she popped out. Loaded with rust. Almost looked like brown sugar.. totally dry meaning that Wd40 didn't reach that far back. Think the heat also really helped. The hole was completed packed with brown sugar rust. Made a little hook scraper with a coat hanger and was able to scratch and pull about 90% out. Then used compressed air to blow it out, then alittle brake cleaner, then more WD40. Pumped a few shots of Marvel mystery oil in there to sit. I need to find a long M8x125 tap to tap that hole better the standard size tap is too short. But should be good. Hope this helps someone else. If you feel like the bolt is going to snap STOP!! and regroup. The bolt was seized in the block at first and felt like it was going to snap. I used heat from a small propane torch directly in the center of the bolt head, the heat traveled through the bolt to the rear threads, careful not to torch other things on your engine when doing this likes seals you new block paint ect, I was careful. After heating the bolt in the center, get a ratchet and SLOWLY turn the bolt if it feels like it's going to break Stop and reheat. I was able to get it out of the block but my problem was it was stuck in the timing cover due to and insane amount of rust. Cheers Thanks for the help fellas. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.