Novak Conversions Jeep Wrangler TJ engine mounts

Stripped front oil pan bolt

Zorba

"The Veiled Male"
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Recap: Last year when I bought this Jeep, I noticed fairly quick that the oil pan gasket leaked right at the very front. I had the gasket and rusty oil pan replaced. Oil leak gone.

Yesterday, I noticed that it was leaking in the same place again. I tightened the front bolts, and it appeared to stop - it certainly slowed way down. However, this AM, I go out and to zero surprise to my paranoia, its leaking again - PUKING oil out. Fuck. Put a socket on two of the bolts - one of them has an obvious problem - won't tighten.

What now? I'm ASS-U-ME-ing that the bolt is stripped. Either that, or its broken. I didn't whale on it tighening it up - I suspect a stripped bolt was the problem all along. If it isn't broken, can I drill and re-tap for a 5/16"? Or Heli-coil it? Advice please...
 
My front bolt that goes into the timing cover was loose - turned out that the threads in the timing cover were stripped.

Out of luck, I had a bolt from an old valve cover (maybe an old Dodge V8) that was similar in size, shape and thread, but only 1/4" longer. I screwed it in and viola! It caught enough threads to tightened up. If I ever had to drop the pan again, I would possibly run a stud in that location with a good amount of threadlocker on it (to preserve whatever threads are left). Could be worth a quick trip to the hardware store...
 
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My front bolt that goes into the timing cover was loose - turned out that the threads in the timing cover were stripped.

Out of luck, I had a bolt from an old valve cover (maybe an old Dodge V8) that was similar in size, shape and thread, but only 1/4" longer. I screwed it in and viola! It caught enough threads to tightened up. If I ever had to drop the pan again, I would possibly run a stud in that location with a good amount of threadlocker on it (to preserve whatever threads are left). Could be worth a quick trip to the hardware store...
This is a common problem. Since there isn't much pressure on these, I've repaired them two ways. One is to drill out the timing cover and install Helicoils. A second way is to get a 1/4 all thread, or a longer bolt and cut the head off, JB Weld it in place, give it 24 hours to cure, then double nut it. Basically, you install studs instead of bolts. I've done the later several times and never had a failure.
 
What now? I'm ASS-U-ME-ing that the bolt is stripped. Either that, or its broken. I didn't whale on it tighening it up - I suspect a stripped bolt was the problem all along. If it isn't broken, can I drill and re-tap for a 5/16"? Or Heli-coil it? Advice please...
For one or two holes a heli-coil will be perfectly fine…

I prefer time-serts myself but it’s a little bit more involved and more expensive to go that route…
 
The solution above are good, especially the stud method for future pan removal without having to disturb that location again. Although I don't see a new timing cover being so expensive that it wouldn't be a reasonable alternative solution either. Last I checked Mopar is about $120 and aftermarket is less and works fine too.

Assuming by "front" bolts, you mean one of the 4 that threads into the timing cover. If it's one of the nearby ones in the block that's likely a bigger issue but I doubt one of those stripped out, the aluminum TC is much more likely to do that.
 
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For one or two holes a heli-coil will be perfectly fine…

I prefer time-serts myself but it’s a little bit more involved and more expensive to go that route…
This is absolutely the best way and as you've said, more time consuming and expensive! (y)
 
Ah! So the front bolts thread into the timing cover - which is aluminum. That explains much. I was wondering how a 1/4" bolt could strip out in cast iron - it isn't. Aluminum annoys me - its shiny, and it stinks like a Mackerel in the moonlight.

I'm thinking a Helicoil would mean I'll need to drop the pan? Which is why I was asking about drilling and tapping to 5/16" instead.
 
This is absolutely the best way and as you've said, more time consuming and expensive! (y)
We install Time Serts all the time with the same exact tools for Heli-coils with the addition of a jam nut. Takes the exact same amount of time and effort. I don't own any Time Sert stuff except the inserts.
 
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Ah! So the front bolts thread into the timing cover - which is aluminum. That explains much. I was wondering how a 1/4" bolt could strip out in cast iron - it isn't. Aluminum annoys me - its shiny, and it stinks like a Mackerel in the moonlight.

I'm thinking a Helicoil would mean I'll need to drop the pan? Which is why I was asking about drilling and tapping to 5/16" instead.
Try the longer bolts first.
 
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Ah! So the front bolts thread into the timing cover - which is aluminum. That explains much. I was wondering how a 1/4" bolt could strip out in cast iron - it isn't. Aluminum annoys me - its shiny, and it stinks like a Mackerel in the moonlight.

I'm thinking a Helicoil would mean I'll need to drop the pan? Which is why I was asking about drilling and tapping to 5/16" instead.
I don't think you're going to have luck doing that unless you're planning to drill out any future oil pan gaskets at that bolt location. They are rubber gaskets molded to metal sleeves for the bolts to go through and are sized accordingly, which is to say 1/4 in most locations and 5/16 in 4 corner locations. Unless you can confirm the gasket sleeve will already accept a 5/16 bolt (pretty certain it will not), I would not plan on that method.

Longer bolts would be my first attempt as well.
 
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We install Time Serts all the time with the same exact tools for Heli-coils with the addition of a jam nut. Takes the exact same amount of time and effort. I don't own any Time Sert stuff except the inserts.
This is good to hear. Being new to Time Serts, I was under the impression you needed the kit, tools included, which are ridiculously priced.
 
We install Time Serts all the time with the same exact tools for Heli-coils with the addition of a jam nut. Takes the exact same amount of time and effort. I don't own any Time Sert stuff except the inserts.
How do you get a somewhat precise counter sunk relief for the insert’s top shoulder? Just a regular countersink taper bit in the appropriate size?
 
This is a common problem. Since there isn't much pressure on these, I've repaired them two ways. One is to drill out the timing cover and install Helicoils. A second way is to get a 1/4 all thread, or a longer bolt and cut the head off, JB Weld it in place, give it 24 hours to cure, then double nut it. Basically, you install studs instead of bolts. I've done the later several times and never had a failure.
I tend to lean towards helicoils, just because I've had great luck with them solving the problem. Used a helicoil on this exact same problem on my buddy's XJ a few weeks ago.

One thing to remember is the torque spec on the oil pan bolts is way lower than you'd expect...something like 85 inch-lbs on the smaller bolts and 130 inch-lbs on the bigger ones. On stuff like that I always assumed "just get it good and tight so it doesn't leak" was a great strategy. Like so many times before, I was wrong.
 
I tend to lean towards helicoils, just because I've had great luck with them solving the problem. Used a helicoil on this exact same problem on my buddy's XJ a few weeks ago.

One thing to remember is the torque spec on the oil pan bolts is way lower than you'd expect...something like 85 inch-lbs on the smaller bolts and 130 inch-lbs on the bigger ones. On stuff like that I always assumed "just get it good and tight so it doesn't leak" was a great strategy. Like so many times before, I was wrong.
Last I checked in the FSM, it's 120 in-lbs on the 1/4" and 156 in-lbs on the 5/16". Ironically enough, I always thought the same thing about just getting them good and tight, except that my version of that was not enough torque and every last one of my bolts were under torqued. Now I just default to the torque wrench and skip trying to get it right on my own.
 
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Last I checked in the FSM, it's 120 in-lbs on the 1/4" and 156 in-lbs on the 5/16". Ironically enough, I always thought the same thing about just getting them good and tight, except that my version of that was not enough torque and every last one of my bolts were under torqued. Now I just default to the torque wrench and skip trying to get it right on my own.
Yeah, I used to find getting the torque wrench out was a chore, now I look forward to it, because it means the job is done AND I don't have to wonder if a bolt is tight enough.
 
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The solution above are good, especially the stud method for future pan removal without having to disturb that location again. Although I don't see a new timing cover being so expensive that it wouldn't be a reasonable alternative solution either. Last I checked Mopar is about $120 and aftermarket is less and works fine too.

Assuming by "front" bolts, you mean one of the 4 that threads into the timing cover. If it's one of the nearby ones in the block that's likely a bigger issue but I doubt one of those stripped out, the aluminum TC is much more likely to do that.
The Mopar cover is discontinued and the aftermarket covers have significant fitment issues.
 
How do you get a somewhat precise counter sunk relief for the insert’s top shoulder? Just a regular countersink taper bit in the appropriate size?
It isn't that precise. For something like the oil pan bolts it would not even have to be flush. But we do give them a little kiss with a no flute countersink just to knock the edge off.
 
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Ah! Now *THIS* is the $15,000 clue. That's fast and easy, even a dummy like me can do it. I'll start there. If that doesn't do it, I'll take a look at alternatives.
If you thread in the next longer bolt length and it bottoms out, you can add a washer under the head to get some squish on the pan gasket without grinding the bolt shorter.
 
Novak Conversions Jeep Wrangler TJ engine mounts