98 Montero 2.5 Harmonic Balancer broke

[nwoods]

Swift_4a, I am quite willing take some photos for you, but I have a 2002 3.5, and the front plate/accessory mounting is different from the 1998-2000's 3.5's. However, the photos still might help, but honestly, I am having difficultly visually or understand exactly what you're looking for. I do happen to have a large number of engine photos on my website, that might help? Take a look (and keep scrolling):

3rd Monty Restoration - nwoods

3rd Gen 2002 Montero restoration and engine rebuild

nwoods.smugmug.com

PS: Thanks for that link to the crank bolt tool, that looks awesome and would have saved me a LOT of effort. FWIW, my cordless Sears 18v impact does get that bolt off just fine, but I have remove the front end to use it.

 

[Swift_45a]

I am having difficultly visually or understand exactly what you're looking for.

Yeah, I had gone into greater detail in my previous post but then it got deleted when I hit submit and and it required I log back in.

Right, well this the tension bolt in question, its the one attached to the tension pulley seen in the pics:


In the pictures its completely unattached/unthreaded and is completely loose as I got the Alternator belt back on. Gen 3s are different, but maybe the same still applies, or hopefully OP or anyone else with a 2.5 can post a picture of how there's look?

My bolt keeps going out of the slot as I tighten it. I saw this thread with you in it trying to find a 2.5 with this issue:

Gen 2.5 Alternator HELP

My alternator started to go bad in the middle of a 1000 mile road trip in Southern Colorado. I replaced my battery (Group Size -24 / 700CCA) and made the 7 hour drive home by the skin of my teeth last weekend. My battery will stay charged (11v-12v) at high revs, but voltage drops at lower revs...

www.expeditionportal.com

He never did post a picture of it properly installed.

 

[PacS14]

That looks worn out to me, you might be able to get away installing a washer. I don't know how hard it is to tighten that tensioner for you, I always end up loosening the bolt on the actual pulley (literally just break it loose), then I tension the belt with the tensioner bolt, and last I go back and tighten the bolt at the pulley. Maybe you are encountering too much resistance because that bolt on the pulley also helps to hold it in place.

 

[nwoods]

Oh yes, I remember that damn thing. First, you have to realize that I have zero mechanical aptitude, knowledge, training, or skill. On my Gen 2.5, i saw the tensioner bolt as sort of a screw drive mechanism, and went at it with my impact to loosen the pulley, as it is clearly meant to if you are a novice like me. It was only after nearly destroying the soft aluminum mount that i learned about loosening the bolt through the middle of the pulley, which left me with a tensioner bracket all wallowed out a bit like yours.

I used a medium screwdriver handled pry bar (the cheap harbor freight pry bay set with the slightly angled tip) wedged up between the steering rack (or sway bar?), to push and hold the long tensioner bolt in place while I quickly snugged it up with my impact, so that the head of the tensioner bolt sat against the meat of the bracket. The pry bar was pushing directly on the threads along the shaft of the tensioner bolt, but not in a critical spot, i figured a few mangled threads was worth it to get the belts tight.i dint think it a actually did any damage, I didn’t have to hold the pry bar in there very tight. Just enough to prevent the head of the bolt from walking out of the slot. As said in my original post, you aren't going for tight, just snug. Then tighten the center pulley bolt. i used medium threadlocker on the pulley bolt. I cant off hand remember if that is blue or red.

 

[Salonika]

Maybe the threads are jacked and the bolt is going in crooked?

 

[MontyTX]

So I talked w the mechanic where I had my Montero towed to in OK and he said that HB bolt basically just backed out on its own and the HB popped off which is what I saw but I thought it had broken. They put it back on then I towed it back to Dallas where my mech who did the TB and pump kit got it back up and running. Wondering if they didn't correctly torque it during TBelt install initially.

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[PacS14]

If it's the updated bolt then that's more than likely what happened, but chances are they will deny it.

 

[MontyTX]

That's what I'm thinking but the timing was off also. Motor would turn but not start. Well I'm back up and running now. Will offer new HB bolt soon just to make sure.

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[Swift_45a]

That's what I'm thinking but the timing was off also. Motor would turn but not start. Well I'm back up and running now. Will offer new HB bolt soon just to make sure.

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This is why I'm entirely averse to having other people work on my cars, I've been in the Industry as a tech before and the amount of carelessness and neglect (often not the tech's faults as you have a ton of cars to get through to make any money or risk falling behind and missing the deadlines) was often so daunting to see that I was resolved to always have a back up car to drive while I work on the other.

I'm about to tear into mine tomorrow now that the parts are here, but I also found this thread on 4x4 wire with some useful pics:

Crank pulley wobble with new pulley and tight bolt - 98 Montero - 4x4Wire TrailTalk

4x4wire.com

Does anyone have a pic of the 2nd iteration of the bolt? I think that is the one on mine, its shorter like the urrent one, but has a 1/2'' insert ID in the center as well as being 22mm OD. I've never seen this one, as I've only ever seen the OEM 1st one and the updated 'pink' bolt, which i have.

As for the pulley bolt itself, that's how it sits when its just completely loose on both sides, but once I hit it with an impact it is roughly the same angle. I think I'm going to have to use washers or some thing to properly align it when its done. I also need to replace the center pulley nut as I managed to strip it.

 

[mobydick 11]

Have you pulled apart the motor yet ? I had something like this happen once. The crank shaft had broken just inside the motor . First it through the belts .we put new belts on and it did it again ,then we noticed the balancer wobbly . funny thing is it would still start up and run .Be for you pull the hole top end off ,pull the pan and just check the crank . It was on a GM though.

 

[MontyTX]

Swift, thanks for the info. I've never done a HB but that's definitely a good link with more great info. Running fine, don't see any wobble but I'll follow up that new bolt.

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[RyanY]

Have you pulled apart the motor yet ? I had something like this happen once. The crank shaft had broken just inside the motor . First it through the belts .we put new belts on and it did it again ,then we noticed the balancer wobbly . funny thing is it would still start up and run .Be for you pull the hole top end off ,pull the pan and just check the crank . It was on a GM though.

There shouldn't be any reason to take the engine apart. The bottom end of the Mitsu V6 is extremely stout and the problems associated with the front end of it are about 1/2 improperly done timing belt services and 1/2 crankshaft bolts breaking because they haven't been updated to the newer style bolt.

Pulling the pan isn't possible with the engine in the Montero, so that's a huge amount of extra work that's really unnecessary for what his issue is.

 

[mobydick 11]

There shouldn't be any reason to take the engine apart. The bottom end of the Mitsu V6 is extremely stout and the problems associated with the front end of it are about 1/2 improperly done timing belt services and 1/2 crankshaft bolts breaking because they haven't been updated to the newer style bolt.

Pulling the pan isn't possible with the engine in the Montero, so that's a huge amount of extra work that's really unnecessary for what his issue is.

Yes I should have read the other posts closer . I did not have coffee yet so my mistake .If a bolt fixed it that's great .

 

[Swift_45a]

So, Day 1 Update (Sorry for threadjacking, but hopefully this helps put everything in 1 place).

- I noticed that the unbalanced HB had melted the timing cover plate so I had to trim it as it was nearly touching the Timing melt as a result.

- The belts, and HB came off easily enough; I can't stress how important PB blasting everything makes your life when you're ready to wrench.

- But when I pulled the HB the bolt is still like nothing I have ever seen on a Montero, I will post pics in a bit to the imgur file. It looks after market and not at all OEM, it has a 1/2'' center insert to thread.

- Also I got super confused with this Timing belt sprocket, and it looks entirely flush unlike the ones posted on 4x4 wire with the little round peg/dowel extrusion on it. It looks like its completely sheared off smoothl to me now upon review, which means its really damaged at this point and will have to be replaced, which means another week's wait. The woodruff key looks intact, though.

- And my updated OEM Crankshaft doesn't go in all the way just hand tightening it so I stopped for the day and decided to verify if any of these things were issues before I move any further.

- Does anyone know the the thread/pitch of the Timing Belt cover plate, I'm missing the lower bolt going into it, and after trying to source the part number with the only dealership nearby I came to the conclusion everything is a weeks time away. He said he'd email me the schematic to point it out as I only had the FSM and its not in there, but I never got anything from the parts guy and I'd rather avoid dealing with that place if I can avoid it at this point.

Thoughts?


Edit: Update on timing sprocket.

 

[Swift_45a]

So, a continuation in what has seemed like an endless saga (working on cars during COVID is horrible, I don't recommend it as availability takes weeks in leadtime for Mitsubishi from GA).

So, after evaluating the situation on the Timing sprocket it looked like more damage had occurred than previously thought. So I took the timing cover off to inspect things closer and here is what I found:

How this stayed on and kept turning on is still a mystery to me as you can see a gap inbetween the timing sprocket where the splines had worn down to nothing where the woodruff key attached to the crankshaft is would in my opinion result in enough shaft play as to throw the thing of timing:


Furthermore, the slack from the wobbly HB created an instability that not only melted/chewed up the lower timing cover, but it also thrashed the timing belt itself, and it looks like a something had a proper gnaw on the end of the belt:


So, in total I had to wait for a HB and bolt from NJ, a timing sprocket, woodruff key from GA, then when I realized the spacer/pins on the timing sprocket shattered I had to wait yet few days from NJ to send me a spacer. I was supposed to get a timing belt from NJ, but decided against it and just bought one from Autozone to finish this as they offered overnight shipping where NAPA tried to waste my time.

I'm to the point where I think the timing belt had enough damage that the fraction of the tooth being off was a result of that as all the tensioners keep everything in place after 2 rotations, and the hydrolic tensioner is fine as well, perhaps torqued too high as I don't have a inch/lbs wrench but otherwise is holding as it should and gives removed the extra slack fine.

Anyone have any recommendations on where to start when wrapping the Timing belt to ensure the cams don't slightly move? I start at the water pump move on to the cams (where the Left bank has a slight bit of play looking from inside the car) and then make my way to the tensioners and then try to get it around the timing gear while the two tensioners are only 1/2 way on. Its a real struggle not get either to slightly move as its so snug. I normally have the Hydrolic tensioner off and loose until its all on otherwise it won't fit at all.

I've had 3 Montero rigs over the yearswith just about every V6 option but this will seriously be my last ICE car, its hard to believe that what is probably $2 worth of metal almost destroyed my engine. EV may have certain impracticality about it but the truth is we can 3d print metal right now and this design is so archaic that I can't see myself being at all interested in it anymore.

Its like looking at a steam engine and being dumbfounded it worked to do what it did, but at the same time being struck by how absurd it all was.

That's how I feel about ICE now.