stripped threads or helicoil?

Hey y'all.  Working on a 98 ranger 4.0.  Replacing the thermostat housing/water outlet and even while being careful...the threads let go.  I promise I was being careful, this truck has given me quite the headache.  

This sort of looks like a failed helicoil, but I can't say that I'm an expert.  

Because the sequoia was totalled i sort of need this on the road for kid duty now that we're down to one car. 

A. Is this a stripped thread or helicoil? 

B. What should be my next step? 

C. If i need to helicoil this....how do I determine size? 

In a bit of a rush.  thanks y'all! 

The OD is too smooth to be helicoil, so I think that just sheared the original threads out. Helicoil sizes are spec'd around the original bolt size, so I'd just grab a kit for the bolt size you have there. It will include the drill bit you need to oversize the hole and tap for the coil

Thank you! 
This is going in what I assume is an Aluminum Intake...any issues there? 

I wonder if the intake got hot and that lead to failure....I was awfully careful. 

In reply to grover :

It is also 25 years old, haha

It could've been overtightened previously. It also could've been nearly over-tightened and then thermal expansion tightened it even further. Aluminum does not do well with repeated high loads, so there just might have been nothing you could do at this point. I am assuming though you stripped it on the way out. If it stripped on the way in, you might've over-tightened it or just tightened it beyond what the fatigued threads could handle. 

on the way in....it was barely over finger tight, started to snug and then just gave away at a point that seemed very early.  
You're right, could have been fatigue.  

My LS aluminum engine did this on a couple head bolts, looked just like that but it pulled all of the threads. Luckily it was before I did the first angle for the torque to yield bolts. Found other threads for head bolts suspect as well.  Now I am in the middle of putting in Time-Serts on all the head bolts, what fun.

cyow5 said:

The OD is too smooth to be helicoil, so I think that just sheared the original threads out. Helicoil sizes are spec'd around the original bolt size, so I'd just grab a kit for the bolt size you have there. It will include the drill bit you need to oversize the hole and tap for the coil

Agree with all of this

Grabbed the M6 helicoil set.  No drill bit unfortunately but according to the googles 6.25 is correct for aluminum.  I believe I have that.  We'll give her a try tomorrow.  I'm a little nervous given it's a part that needs to hold tightly and seal....but I suppose it's the right part for the job.  

grover said:

Grabbed the M6 helicoil set.  No drill bit unfortunately but according to the googles 6.25 is correct for aluminum.  I believe I have that.  We'll give her a try tomorrow.  I'm a little nervous given it's a part that needs to hold tightly and seal....but I suppose it's the right part for the job.  

For critical fastener repair in aluminum, especially if re-used often, I prefer TimeSert over Helicoil. 

Just finished up redoing the engine mount bosses on one of my K24's for the CRX that's been in/out of the car dozens of times over the years.

That's good to know, thank you Andy. 
 

this was nerve wracking but I went slow and it seems to be fine.  I am not 100% sure on depth so I added a small washer. The tap was bottoming out despite blowing out with compressed air and I didn't want to push it. 
 

I do still have a leak at the interface and I guess I'm going to add some permatex. The flange is coated in a heavy paint and I'm guessing it's not sealing well. Ford no longer makes this housing so it's a duralast part. 
 

The defcons have been upped. 

I'm late here.....

When I had a similar problem on an Aluminum Buick manifold the shop guy said: "Helicoil and use a stud in the bore....."

Rog

Well Team, 

This joy of a soap opera has not yet reached it's conclusion.  

I was so frustrated with the missteps so far that I followed very closely the permatex directions. single bead all around including bolt holes.  Finger tight, let it sit for an hour.  Then full torque and wait 24 hours.  I gave it 36 just because I'm tired of messing with this truck. 

Went out this morning with coffee in hand, a little nervous about this not working even though I followed all the steps. 

It's about this time that I should say that while this used to be our 3rd vehicle and it's running was not key to household function, my Sequoia was totaled last week and we're down to the GX and this..and we have a 13 and 14 year old that need to get ferried to two different schools.  So now that we're down to one car, the truck needs to go from backup duty to starter.  

I make sure all connections are good.  Put coolant hose on carefully, truck is now being treated like a newborn with a soft skull.  

Pour water in the radiator (why risk coolant on the ground when it's been leaking like a used tent?) and proceed to hear drips. Surely this is just from me missing the small coolant fill right, I mean, the bottle was full- I missed a little.  Nope, coming from center of the motor.  How can the water outlet be leaking now--- it doesnt appear to be wet! Grab headlamp...put on reading glasses (man getting old is weird).  It's like looking into a cave from the front opening, but I believe that I can see water just behind and to the left of the opening....running.  It's coming from the intake.  I can't tell if it's the gasket, or a crack or what. 

So.  What to do.  

This was my grandfathers truck. Ordered new with the 4.0.  Almost exactly 225,000 miles.  It's a 5 speed which is fun and the truck looks nice. I probably can't get rid of it, and deep down I don't want to.  It's a good looking little truck, fun to drive and is different.  Ideally it would sit in storage.  It's not ready for prime time for sure.  

This appears to be on the verge of needing the top of the motor off, at least the intake.  The valve covers are leaking terribly, so I guess this could be two birds in one stone.  Intake gaskets/make sure it's not cracked, and valve covers.  The truck would then seemingly be good to go.  I'm fairly certain I have the skills to do this, I just don't really want to right now. 

I do have tabs open in this window from last night looking at camry vs accord hybrids.  We drive a lot, we previously had two v8's and we are thinking about moving at least one car in the fleet to more than 15mpg.  The gx averages lifetime 15.2 and takes premium.  WOOF.  If we can shift some miles to a 40+mpg then we save quite a few doll hairs.  I did not want to do this now, but......now I'm looking at easy buttons.  

Check my math- Maybe rent a car for a week- probably $500 so I can do kid duty and parts store duty, dive into this motor and make sure that it's done right rather than a shop that I don't have a relationship with? This seems like the wisest thing to do but granted not the most fun. 

Second option: go ahead and buy the hybrid. Fix truck over time....which I'm sure i'd put off.  

TL;DR.  Truck still not fixed.  More things are broken. Grover is sad.  May need mechanic recomendations in Jupiter, FL. 

Keep at it. I had a 94 explorer and loved that little truck.  I sometimes find my self searching around the southern states for a ranger with the 4.0 of similar vintage. Also those wheels are one of my favorite. 

Oh don't feel to bad about your MPG situation.  My new to me back up car has averaged  11.7 mpg over the last 500 miles and runs high test.  Makes my v8 dd look like a economy car.  It averages about 24 mpg. 

I'll vote the other way, nothing is more frustrating than a daily that can't perform it's duty, and playing combat mechanic isn't fun when you're under the gun.   I'd say grab one of the hybrids and enjoy 40+mpg while you fix the truck you care about properly so it's a good memory, not a burden.

Being in a rush and working on a 26 year old vehicle isn't fun..  Been there!

Sounds like the 13 & 14 year old should get to learn about how engines work :)

Great truck, love the history. I agree that if you can afford another vehicle, I would recommend using it as a backup/truck requirements vehicle. I've had my GMT400 in that role for about 15 years.

Grover, perish the thought of getting rid of the truck over this. Keep in mind one GRMer probably has more technical savvy than the entirety of the UAW that put these things together in the first place. You will win.

A few things to check/comments:

Did you knock off and retrieve the helicoil tang? They're mildly magnetic. Your photo with the water neck installed looks like the bolt in question isn't bottomed. If the tang is still there, it can cause false bottoming. You should be able to easily thread a screw with good threads all the way to the bottom of the hole by hand. I've seen helicoils that distort or skip a thread at the bottom if the tang was screwed into, causing a locked thread and again, false bottoming. If yours is like this, it needs to be R&R'd. 

New t-stat gasket right? There really shouldn't be a need for RTV. I don't like the vertical t-stats, they can be hard to get seated correctly and have a nasty habit of falling slightly out of place just as you add the water neck and becoming a leak-generating shim. The classic Ford SB is terrible about this since it only has a shallow recess for the t-stat and uses a thin paper gasket.

Does the new water neck have a flat sealing surface like it's supposed to? The paint/powdercoat is probably fine, but that thing needs to be flat. No guarantees from Duralast...

Are you sure the thermostat housing was the leak? I helped a friend tear apart the front of his similar vintage Explorer to replace water pump and timing cover, thinking that was the source of a water leak. When we were done, there was still a leak down the passenger side front of the engine. Turns out the plastic intake manifold had a crack (or mouse bites? I don't recall). Replacement intake manifold fixed it. 
<edit> oh dang, now I see that you said it is an alum intake. 

Nockenwelle said:

Grover, perish the thought of getting rid of the truck over this. Keep in mind one GRMer probably has more technical savvy than the entirety of the UAW that put these things together in the first place. You will win.

A few things to check/comments:

Did you knock off and retrieve the helicoil tang? They're mildly magnetic. Your photo with the water neck installed looks like the bolt in question isn't bottomed. If the tang is still there, it can cause false bottoming. You should be able to easily thread a screw with good threads all the way to the bottom of the hole by hand. I've seen helicoils that distort or skip a thread at the bottom if the tang was screwed into, causing a locked thread and again, false bottoming. If yours is like this, it needs to be R&R'd. 

New t-stat gasket right? There really shouldn't be a need for RTV. I don't like the vertical t-stats, they can be hard to get seated correctly and have a nasty habit of falling slightly out of place just as you add the water neck and becoming a leak-generating shim. The classic Ford SB is terrible about this since it only has a shallow recess for the t-stat and uses a thin paper gasket.

Does the new water neck have a flat sealing surface like it's supposed to? The paint/powdercoat is probably fine, but that thing needs to be flat. No guarantees from Duralast...

no, I could not get the tang to break off.  I do believe that it may be bottoming out on that.  How do you remove the insert? It did not want to back out....that's why i used the washer.  I did not like doing it, but I was unsure of what else to do.  Great eye on that and great experience.  

I agree on the placement of the thermostat.  It's sitting flush against the engine sort of like if it was against a wall, but I guess you can see that.  The old one was in backwards.  I'm not sure when it was replaced.  

I did check the flange and it seems to be reasonable flat.  I did consider flatting it on some flat surgace with sandpaper but decided against it.  

Thank you for all your help.  I have/had no doubt I'd get answers as I've read thousands of threads on here over the years while mostly lurking.  

I decided to dig into it.  I'm starting a new job 1/8 and while is a pretty substantial raise (double my current base salary), it does bring a bit of uncertainty and I'd like to preserve funds over the holidays.  

I went ahead and bought the feelpro kit for upper and lower intake as well as valve cover gaskets.  This truck needed them pretty badly and I didn't want to do it, I figure I might as well now.  

I started with all the accessories which I had gotten pretty dang good at taking the fan and serpentine out.  

For a small truck and a decent size motor, access is not terrible.  The joy of the V6 I suppose. 

Next got the upper plastic intake off after much confusion over the way that EGR pipe hangs it up.  

it's dirty. I cleaned it up after stuffing some shop towels in it. 

then I was able to get my phone in and take the following photo. 

The red arrow on the right is the coolant housing/water outlet that I had just repaired.  It's dry mostly.  

To orient, you are looking at the motor from about fan clutch level from the left front of the motor towards the center of the block. 

The left arrow points to where I think the leak is.  This is the interface between the lower intake, heads and block. Does it not look like this is where the leak is? It's wet, and yet uphill with no obvious path from the water outlet. I guess this is what needs to be fixed now. That's going deep into this thing- Can i do this and keep the heads in? I'm 99% sure the answer to that is yes, but I REALLY don't want to do a head gasket. and on second thought....no chance this is a head gasket, right? I haven't looked for white smoke but heck, this thing pours out when it's off and cold and I'm just filling the radiator.  

Need hive thoughts here and if this is a worthy endeavor.  

Also I need a break.  I ran a 104.1 mile trail race two weeks ago and tore my achilies 61 miles in.  The ankle is not happy after leaining over the front of the engine bay for an hour and 45 minutes this morning. 

Probably could use a change of title at this point if someone could help.  98 ranger 4.0 coolant leak should work. Thank You. 

Still thrashing on this thing.  Got the valve covers off and wiped one down with a stiff brush and some dish soap.   Gaskets were brittle so probably original.  

Now on to the lower intake. 

Off to take advantage of the harbor freight sale and buy my christmas present.  Wife said go buy it.  anticlimatic but excited.  

Harbor Frieght Sales are so shady.  They don't have the toolbox that they say online they have, only the updated one.  Fine, it's 900 rather than 350.  Inside Track discount to $750.  I have the "no exclusions" 20% off with Inside Track membership.  They claim inside track membership is a coupon and they can't honor it.  I did not get a toolbox tonight on principle.