I recently purchased a 2005 Toyota Corolla with an automatic transmission. The car is in decent shape with 180k miles. When I bought the car I scanned it and it was showing no active codes or any in the history. The two main issues it had was a squeaking serpentine belt tensioner pulley and what sounded like an exhaust leak from the area of the manifold. Nothing crazy to repair on my own with one of these cars.
I took the car for a test drive and the motor seemed to run perfectly besides the squeak. The transmission shifted smooth as can be, so I decided to buy it. So here’s the good part, while changing the serpentine belt tensioner, it turns out the reason it was squeaking is because the previous owner, or someone else who’d worked on it, had broken the original tensioner bolt off inside the motor while servicing the vehicle. They’d used a different bolt with some sort of spring attachment over the end to hold the tensioner in place just enough to work.
When I was done swearing at myself for being such a fool, I did some research online and discovered this bolt breaking is actually a relatively common issue in these vehicles. The common fix seems to be removing the passenger side motor mount and jacking up the motor enough that you can use a right angle drill to drill the bolt and remove it with an extractor. Sounds like a real PITA, but I didn’t pay a crazy amount of money for the vehicle and am willing to at least try this before throwing in the towel. Others have done it after all. I’d hate to scrap it because of a bolt that cost $12 since it really is in decent shape and the motor runs great except for this.
My biggest fear is that the person who’d worked on it before me may have damaged the threads, making an already difficult job basically impossible. From what I can see the threads still seem to be in decent shape though so we’ll see. The plan as of now is to say a prayer and try the angled drill method. Any advice would be greatly appreciated. From one Rhode Islander to another, have a Happy New Year!
If it turns out the threads have been stripped out use a Timesert thread insert to repair it.
Thanks Chuck. Did some more searching and it looks like the spring gizmo that was in there was actually a wire helicoil. We’ll see how it goes, pray for me haha.
If the Helicoil came out you definitely have some thread problems going on in there. Look into using a Timesert instead, they are generally considered to be superior to Helicoils.
Will do. Do you think that the fact this was in there will make it possible to remove what’s left of the old bolt from inside the motor? There’s about a half inch of exposed thread inside the hole before the broken end of the bolt. Also will a timesert require me to use a different size bolt? Sorry I’m not familiar with how they work.
It's hard to say without seeing what's going on. If the bolt is cross-threaded in the block getting it out could be a challenge. There are plenty of videos on youtube showing bolt extraction under different circumstances so I'd recommend doing a little research to minimize chances of making things worse.
Got it, I’ll do some more digging and update if I’m able to get it out. Thanks for the help.
Get the Timesert kit for the size of the bolt that's original.
Ok. Thanks for the reply. Assuming the rest of the bolt comes out the thing that will make it difficult is the angle and amount of clearance that I’ll have to work on it. I’ll update when I’ve gotten further along with it.
Also, for anyone who has this same issue it looks like the bolt threads are 11mm, so you would need a timesert kit for that size.
You said you have the broken bolt. Measure it and see and even compare it to another engine bolt to make sure. 11mm sounds way too big for a tensioner bolt. Should be more like 8mm. What size socket fits the bolt hex head? Make sure to measure the thread pitch as well.
Sorry, I was wrong. Apparently the bolt is 17mm.
Reading the specs on the replacement bolt I purchased, the threads are 11mm while the head for it is 17mm. I’m going to see if I can remove what’s left of the broken bolt inside the motor. If someone put a helicoil in there, I’m assuming they would’ve had to bore the hole a little bigger, so I assume it won’t obstruct the broken bolt from coming out. Now, assuming I get it out I’ll see if the replacement bolt will securely grab the threads that were untouched by the helicoil. If that doesn’t work, plan B is to get a 7/16-14 timesert kit. 7/16 is slightly bigger than 11mm so hopefully that should grab nicely. Looking at the belt tensioner it seems like there’s enough room for a 7/16 bolt to fit through it. Will update if the bolt comes out.
Yeah try that repair. Just make sure you get good extractor tools cuz cheap ones will break off
Thanks Scotty. In your experience would you happen to know if Craftsman extractors are worth their salt?
Ok, so I had some time to work on the car this morning. With the right tools, a lot of patience, and honestly a good bit of luck, I was able to get the broken part of the bolt out.
I used the angled drill method I talked about before. I supported the engine with a jack, removed the passenger side motor mount and used a battery powered Milwaukee 90 degree drill on the bolt inside the hole. I ended up getting a brand new set of titanium drill bits that chewed through the bolt with relative ease, which definitely made the job way easier. I started off by using a spring loaded center punch and an 1/8 inch drill bit with a #2 fine threaded extractor. I should mention that I dipped the bits in cutting oil before drilling also.
I used a crescent wrench to turn the extractor counter clockwise very, very slowly until it felt like it was starting to spring up instead of turning. I think having a hand on the extractor while you’re turning it really makes a huge difference because you can literally feel the difference between it turning into the bolt, the bolt itself turning, or the extractor flexing, which is what you don’t want obviously. The last thing I wanted to have happen was an extractor snap off in that thing.
I continued to drill and made my way up to a #4 extractor. However, I didn’t drill out the bolt for the recommended size for a #4 since it fit in the hole for a #3. Again, turning the extractor very slowly and not trying to force anything, the bolt eventually began to turn and came right out with ease once it broke free.
Through research, I’m relatively certain that the part of the hole where the helicoil had been was originally smooth and played no part in the integrity of the original threads. Since the old bolt came out easily once it was free, I’m hoping the new one will go back in the same way once it’s here. I went ahead and picked up a brand new tensioner and belt too just to be on the safe side.
I’ve been researching how to remove a broke bolt from a motor like a mad man the last few days. If this hadn’t worked, I think the next thing I would’ve tried would be to weld the end of a smaller bolt to the broken bolt and try to turn it out with a wrench. It seems like a lot of people have had more success doing this type of removal than with extractors honestly. Anyway, I’ll let you guys know how things play out once the new parts arrive. The it’ll be on to dealing with that exhaust leak. Thanks for the help.
Use the correct size millimeter bolt, not SAE. The 11mm bolt is .43307" while the 7/16 bolt is .4375", too big by 4/100".
Ok, I found an m11 timesert kit online, which I believe means 11mm. My fear is that when they drilled the hole for the helicoil they may have oversized it too much for a 11mm timesert to work. I’ll try and get the bolt out and see if the new one grabs the undisturbed threads and go from there.
If they drilled it out for the hel-icoil and you can remove the hel-icoil, use the drill with the Timesert kit to check it. It's always dangerous to assume anything.
Correction - I meant to say 4/1000", not 4/100".
Just wanted to update on this. Got the new bolt and tensioner on with no issues and it’s running great. Thanks for the help.