Loctite makes a stripped thread repair kit, but it's out of stock everywhere 
I might be able to use threadlocker or JB Weld in the hole
I might be able to use threadlocker or JB Weld in the hole
1998 Forester 2.5L; Timing belt, cams ... trouble
- Thread starter slacktide_bitog
- Start date
Doesn’t mean you used it properly. Doesn’t mean your torque wrench was accurate. Doesn’t mean the threads were not damaged by the last technician.I used a torque wrench
UPDATE
I took the 2 bad bolts out, and one of them did have threads on it, which I must not have noticed before. I brushed both bolts off with a brush, then put them back in. One of them finally tightened, but the other is still spinning.
I applied Loctite blue to both of them. If the one that still didn't tighten still isn;t set after the Loctite, I might slather it in JB Weld to see if that works, and possibly JB weld around the top of the hole where the water pump meets the engine.
I took the 2 bad bolts out, and one of them did have threads on it, which I must not have noticed before. I brushed both bolts off with a brush, then put them back in. One of them finally tightened, but the other is still spinning.
I applied Loctite blue to both of them. If the one that still didn't tighten still isn;t set after the Loctite, I might slather it in JB Weld to see if that works, and possibly JB weld around the top of the hole where the water pump meets the engine.
Thanks Debbie Downer!!
Slacktide, you won't get any clamping force w JB unless you're talking about tapping the hole, which guys absolutely have done, but it's booty for something as important as a wp. Plus, you need a way to drill the JB concentric. Just use a thread insert man. In the time you've spent fretting over this you could have thread-serted (sure it's a verb!) all six. Personally I'd only do the offending two and leave well enough alone.
Thanks Debbie Downer!!
Slacktide, you won't get any clamping force w JB unless you're talking about tapping the hole, which guys absolutely have done, but it's booty for something as important as a wp. Plus, you need a way to drill the JB concentric. Just use a thread insert man. In the time you've spent fretting over this you could have thread-serted (sure it's a verb!) all six. Personally I'd only do the offending two and leave well enough alone.
It seems like it might be difficult to insert one of those things here.
The water pump holes aren't threaded, only when you get to the block itself where it's threaded. Is the stock thread size M6? I think that's what I read somewhere. So I'd have to get whatever insert fits in there along with a new bolt
The good news is that now I would only have to do one, as the other one I finally was able top get in tight
I don't want to undo the other bolts because the threads could strip if I ever touch them again
Fix it right. Auto parts stores sell thread repair kits with a helicoil. Watch some youtube videos if you aren't confident. It's quite simple as long as you have access to get the tools in there.
Side note: back a good long time ago I had a roommate that did some repair work on his Subaru. I cautioned him to not overtighten the water pump bolts, but he proceeded to snap one off. Left it as is, and continued to drive it. Not too long after, on a trip to Mexico, the cooling system puked and leaked all the water out. Broke down is Mexico is a great way to ruin your day.
Yeah I'm pretty sure they're M6x1.0, which is a touch under 1/4" (.236" vs .250")
You're going to have an insert kit so don't fear removing the others.
Unless the remaining bolt is not fully seating? Then you can try running a tap or chaser in there.
I'm unclear if it's bottoming on its flange head (abandon all hope) or not STARTING to thread in with a gap remaining under the flange (use a tap or chaser)
You're going to have an insert kit so don't fear removing the others.
Unless the remaining bolt is not fully seating? Then you can try running a tap or chaser in there.
I'm unclear if it's bottoming on its flange head (abandon all hope) or not STARTING to thread in with a gap remaining under the flange (use a tap or chaser)
Something else you could do -- and I'm not kidding: just run a 1/4" tap in there and get a bolt of the same length.
Typically in Al I'd want 1/4-28 but I might opt for 1/4-20 here, wanting it to thread in more like a sheetmetal screw with more meat between the helix than a fine thread which ultimately removes more material
According to the interweb the STI bit size for an M6 Helicoil is 1/4", so you could STILL drill out completely at 1/4" and retap the STI (special thread insert) tap. 1/4" is the MINOR dia of the STI with the threads being LARGER than that.
Yes, this suggestion is somewhat booty but less so than JB Weld!!!
edit: also note such suggestions are predicated on the big picture of a '98 Forester. If this were, say, a 2024 Forester, NO WAY I'd seriously consider this. Where's the line between booty and correct? DEPENDS on a million factors including mileage, condition, age and how long ownership is planned
Typically in Al I'd want 1/4-28 but I might opt for 1/4-20 here, wanting it to thread in more like a sheetmetal screw with more meat between the helix than a fine thread which ultimately removes more material
According to the interweb the STI bit size for an M6 Helicoil is 1/4", so you could STILL drill out completely at 1/4" and retap the STI (special thread insert) tap. 1/4" is the MINOR dia of the STI with the threads being LARGER than that.
Yes, this suggestion is somewhat booty but less so than JB Weld!!!
edit: also note such suggestions are predicated on the big picture of a '98 Forester. If this were, say, a 2024 Forester, NO WAY I'd seriously consider this. Where's the line between booty and correct? DEPENDS on a million factors including mileage, condition, age and how long ownership is planned
I have another idea. Since the bolt that won't tighten has threads in it, I'm considering just buying another bolt, a new bolt from the dealer for $2, and hoping that will tighten. Part number 800106930
It's only a $2 gamble I can do if the threadlocker doesn't hold, or if copper wire won't do the trick. The copper wire's torque capability is approximately that of the water pump threads anyway
I found this video of someone intentionally stripping the water pump bolts and was able to get 20-30 lb ft before stripping, though most people can't even make it to the correct torque spec without stripping
It's only a $2 gamble I can do if the threadlocker doesn't hold, or if copper wire won't do the trick. The copper wire's torque capability is approximately that of the water pump threads anyway
I found this video of someone intentionally stripping the water pump bolts and was able to get 20-30 lb ft before stripping, though most people can't even make it to the correct torque spec without stripping
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UPDATE: I put everything back together and everything seems to be good 
I just need to get another bottle of Zerex Asian Green because I didn't have enough on hand. I will pick it up tomorrow.
I just need to get another bottle of Zerex Asian Green because I didn't have enough on hand. I will pick it up tomorrow.
not to be a negative nancy or anything, but I’d be weary of that repair. can you pressure test it with the timing cover off to build your confidence that the pump will not leak? a little confused why you didn’t helicoil it, there was alot of room in there
A Helicoil would require me to take all the other bolts off, which would probably strip those too
Since 5 were already on tight, and the one that stripped is on top, I don't think it will be a problem
If I knew how fragile the threads are prior to doing the WP, I might have just helicoiled all of them as regular maintenance
I worked in a Subaru shop for a little while and only did a handful of water pumps (being a dealer, we didn’t see many cars come back after their first timing jobs…I figured customers find aftermarket/side shops to do the work cheaper at that point). I don’t remember having any issues with stripped bolts, but again, these were almost all cars that we were the first mechanics to touch them. Water pumps were usually done on the second timing jobs or their inevitable head gasket jobs.A Helicoil would require me to take all the other bolts off, which would probably strip those too
Since 5 were already on tight, and the one that stripped is on top, I don't think it will be a problem
If I knew how fragile the threads are prior to doing the WP, I might have just helicoiled all of them as regular maintenance
Here is to hoping you are right. But I suspect it will leak on you. Keep a close eye on it. Just because it is on top doesn’t mean it won’t leak.
UPDATE: it's all done
Everything is good now, and no more overheating
The timing belt had very fine cracks in it. Of the two smooth pulleys, one was Koyo and one was NSK. One of them may have been leaking, but I don't remember which one it was. I used both NSK to replace them. I think the Aisin kit comes with 2 Koyo pulleys.
I don't think the timing belt, water pump, or any of the rollers had ever been replaced before.
The transmission cooler lines had the stupidest hose clamps I've ever seen, with a screw, a rectangle thing that kept spinning while loosening the screw, and a wire thing that goes over it. I replaced them with regular hose clamps. Even the timing belt tutorial videos all show regular hose clamps.
So if you have an automatic Subaru with a timing belt, have some hose pinchers handy before you disconnect them!
Everything is good now, and no more overheating
The timing belt had very fine cracks in it. Of the two smooth pulleys, one was Koyo and one was NSK. One of them may have been leaking, but I don't remember which one it was. I used both NSK to replace them. I think the Aisin kit comes with 2 Koyo pulleys.
I don't think the timing belt, water pump, or any of the rollers had ever been replaced before.
The transmission cooler lines had the stupidest hose clamps I've ever seen, with a screw, a rectangle thing that kept spinning while loosening the screw, and a wire thing that goes over it. I replaced them with regular hose clamps. Even the timing belt tutorial videos all show regular hose clamps.
So if you have an automatic Subaru with a timing belt, have some hose pinchers handy before you disconnect them!
