Diagnosing and Fixing a 2002 Montero 3.5L V6 SOHC that might be seized up

[nwoods]

I am hoping to crowd source my current project because I am in way over my head. I am learning how to turn a wrench, but my knowledge level about what I am doing regarding engines is laughably insufficient. A smarter person would probably shake his head and walk away, but I am blissfully ignorant, don't have money for professional help, and the engine is already broken, so I have nothing to loose and everything to gain!

I have recently purchased a 2002 Montero Limited with 154,000 miles that shows signs of having been well maintained, but, it has a dead engine. The previous owner just put a ton of work into this (at a small shop that appears to have cut a few corners, or atleast, appear to have broken a few connectors and glued them back together with rubber contact cement). Here is the recent replacement parts list:
- New Radiator (aftermarket)
- New spark plugs
- New timing belt kit with water pump
- New grooved idler pulley
- New smooth idler pulley
- Machined heads with reseated valves, seals, etc...
- New head gasket
- New head bolts
- New coolant

4 days after all this work, the owner reports that it just died on the freeway, and it has not started up again since. It was towed to the shop that serviced it, and they pronounced it dead with possibly a thrown rod. I put a 22mm socket and a breaker bar on the crank bolt, and I can turn the engine back and forth within about 20 degrees of arc, but I can't go beyond that in either direction. When I turn it, there are metallic sounds that should not be there.

I started by removing the front plate, hoping to see a failed timing belt install. Nope, it looks fine.
Then I removed the valve covers, hoping to see a failed rocker arm or something amiss. Nope, it looks fine. Actually, it looks fantastic. Brand new looking (see above work list).

Now I am kinda stuck. I am not sure what to do next. I am hoping you all have some suggestions I can try. I am unable to remove the crank bolt. I have a little tool that locks the crank pulley in place, but it seems that only fits a Gen 2 or 2.3, it does NOT fit the Gen 3 crank pulley. I do not have any air tools, but I have a heavy duty 1/2" 18V impact, that does nothing, and a 3' breaker bar that starts to bend a bit when I try to turn the bolt. Not sure how much oomph to put into that. What if the bolt breaks? Maybe I should try heat?

I could remove the heads, and may resort to that next, I'm just not sure if that is wise.

I am prepared to have to remove the motor all-together, either to replace it or have it rebuilt if the piston or crank or something in the lower half has failed. However, I don't actually know how to pull the engine, having never done that before, and am not sure what to mount the engine hoist too if I remove the heads.....

Thoughts? Suggestions? Reccommendations?
Does anyone have any links to How-To's related to tearing down an engine like this?

Here are some photos:

Left bank (passenger side)

Right bank (drivers side)

Sample of previous work. I could NOT get this simple coolant temp sensor connector off. If you look close, there is black spooge coming out the bottom from where the previous mechanic GLUED it on. Thanks Buddy! Sigh....there are 5 more like this.

 

[vk_miniatures]

At this point, imho, it would be cheaper to swap out another engine. Pull the oil pan off and look at the crankshaft and connecting rods. You could have broken pistons, or rods. Also, if for some crazy reason, timing belt skipped several teeth, you might have broken/bent valves. By the time you get all that repaired, it will cost you an arm and a leg. Just saying

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[nwoods]

All good points, but 1) not sure how to remove the engine, or more accurately, not sure how to separate it from the tranny.
2) if it’s just bent valves, that’s a cheap fix, that can be done with the engine in place, whereas a replacement motor is upward of $1,500

 

[vk_miniatures]

Since pulling engine out isn't an option, at least take off the oil pan to see if any rods are broken. Pull the heads to look inside combustion chambers. Bent valves are an easy fix but if they collided with pistons hard enough, then there will be damage to the pistons as well. You can always buy a replacement engine from a local pick-and-pull and refresh it or use it for parts...

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[normal_dave]

Before you tear in any farther. Something just isn't adding up, with the prior owner's failure description, and your pictures. With me being the eternal optimist, I would want to verify the timing marks, i.e. piston to valve impact? Camera angles hard to judge but does anyone else see a big discrepancy between passenger cam gear mark and driver's side cam gear mark? Did the tensioner give way, did the prior mechanic setup the marks correctly, and rotate the engine through?

If you look at the clock visual settings/relationship of the passenger side cam gear mark to the valve cover notch, the distance around the clock appears to be a lot farther from the mark on the driver's side. Nwoods described not being able to rotate the crank more than about 20 degrees in either direction. Pull the belt, get the cam gears manually set to a "neutral" position if possible, then check the crank rotation by itself again.

It almost looks like right side (driver's) is nearly 10 teeth past the valve cover notch, left side (passenger) maybe only 5 teeth? If this verifies, that's way off, and I'd expect valve to piston impact. If you've been living right lately, maybe you'll end up pulling the heads and have no damage to the pistons. It's a very nice looking truck, and I have so little faith in mechanics being able to speak Montero these days, I expect failure and incompetence.

Edit: Well now that I've seen it on a bigger monitor, I'm not quite as enthusiastic, but check it out anyway...

FWIW, I use a combination of these links to gather information for timing belt jobs, keeping in mind differences, 3.0L, Sport, vs Montero, etc.
3.0L Timing Belt
montero sport timing marks
Timing marks Montero Sport 3.5L
6G74s not created equal

Remember your Montero 3.5L tensioner "sets" in the opposite direction to the Sport 35L. I made this mistake, but caught it during the job. I was following directions, to the letter, but for the wrong engine...Sport vs. Montero.

I've got a feeling you're going to "win" this one, bet the mechanic pooched the tensioner setting on the timing belt job, didn't rotate through two revolutions, let it set, a little high revs on the highway, and BAM. Told you I was optimistic. Let's see.

 

[nwoods]

Before you tear in any farther. Something just isn't adding up, with the prior owner's failure description, and your pictures. With me being the eternal optimist, I would want to verify the timing marks, i.e. piston to valve impact? Camera angles hard to judge but does anyone else see a big discrepancy between passenger cam gear mark and driver's side cam gear mark? Did the tensioner give way, did the prior mechanic setup the marks correctly, and rotate the engine through?

If you look at the clock visual settings/relationship of the passenger side cam gear mark to the valve cover notch, the distance around the clock appears to be a lot farther from the mark on the driver's side. Nwoods described not being able to rotate the crank more than about 20 degrees in either direction. Pull the belt, get the cam gears manually set to a "neutral" position if possible, then check the crank rotation by itself again.

Dave, I measured the timing marks, and both sides have exactly 9 teeth between marks. Photos:

Left:

Right:

Pull the belt, get the cam gears manually set to a "neutral" position if possible, then check the crank rotation by itself again.

I'm a bit stumped on how to pull the belt, I can't get the crank bolt off. I could cut it, but its brand new! Also, how do you "set" a cam to neutral. How would I know where that is?

 

[nwoods]

Since pulling engine out isn't an option, at least take off the oil pan to see if any rods are broken. Pull the heads to look inside combustion chambers. Bent valves are an easy fix but if they collided with pistons hard enough, then there will be damage to the pistons as well. You can always buy a replacement engine from a local pick-and-pull and refresh it or use it for parts...

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I will do the drain pan next. That makes total sense, thanks for point that out.
As for that replacement engine.... LKQ (Pick a Part) charges $2,300 for engines. They are super expensive. Most everything I've seen listed is $1,300 plus shipping:

 

[vk_miniatures]

I'm talking about pick-n-pull yards. You pull parts off cars by yourself . They sell engines around $300-400 as is, but you have to pull it yourself. Also, those engines aren't tested or anything. Perfect for parts though. Also, good way to learn how to separate transmission from an engine . Oh and If you pull an engine from a wrecked car, chances are it might even run. There is a rolled over montero at Rancho Cordova location right now...

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[coffeegoat]

OK - Here's another cheap diagnostic to try after you pull the oil pan (which is a great idea btw) - go buy a cheap borescope. These used to be crazy expensive, but have come down in price dramatically. Pull the spark plugs and take a look in the cylinders. Make sure you pick one that actually fits through the spark plug hole, but it should give you something. I picked one up after doing my rebuild on the off chance I'd need to see something (never did), and I've used them before at my normal job to diagnose some expensive failures - it's really nice to avoid pulling more parts to find the damage.

The engine looks nice and clean, but the discrepancies you've noticed make me wonder if they skipped a step or two during reassembly of the heads. For example, putting the spring retainer back together on the valves is a huge pain, and if you weren't super careful you could get it "almost" correct and then drop a valve which would cause a mess. I also didn't see valve guide seals on the list, which should be done on these rigs anyways because they have a tendency to leak.

As I recall, I picked up a cheap harmonic balancer wrench to remove the bolt, which you will need to do anyways because it appears to be the old style. It really does need a huge breaker bar, I believe on the order of 200 ft*lb (not exact but a bunch).

It sounds like you aren't in a hurry to get this thing sorted out, which is perfect, because with a bit more patience you may get a cheap rig. I'm inclined to agree with Normal_Dave that this is probably fixable, but I'm also pretty cynical and I will assume the previous mechanic buggered it up good for you...

 

[normal_dave]

Looking at the newer pics, I think I've sent you down a dead-end trail. You'll need to get that crank bolt loose. If you don't have the tool, head to your local hardware store, build one like this, use grade 8 bolts, I didn't weld mine, just found thinner nuts and lock-washer to hold the bolts, and bought a longer bolt for the backside of the tool so they matched length at the connection point to the balancer. You can use the same tool for the crank gear as well. Also get a good breaker bar, and maybe a cheater bar too. You may have to build a brace to hold your crank tool, since you cant freely rotate the engine right now. Wood/blocks etc.
crankshaft holding tool

As far as "neutral", that may not be the right term, you can turn the cam gear just left or right of the notch, and the cam will "spring" to the spot where there is little or no spring pressure, ideally valves closed. so that there would be little or no impact to the piston. You'll want a box end wrench and two hands, as it will be difficult to get them to "sit" at the notch on re-assembly without it. It wants to rotate past the notch setting.

You could additionally remover the rocker arm assembly, and the valves would then all be closed. Watch this on re-assembly, because the bolts can stretch/strip if you don't follow pattern or spread the load when re-tightening the rocker arms.

Edit: passenger side cam seal now looks suspect, evidence of the usual oil leak that drops down and eventually takes out the alternator.

 

[nwoods]

I'm talking about pick-n-pull yards. You pull parts off cars by yourself . They sell engines around $300-400 as is, but you have to pull it yourself. Also, those engines aren't tested or anything. Perfect for parts though. Also, good way to learn how to separate transmission from an engine . Oh and If you pull an engine from a wrecked car, chances are it might even run. There is a rolled over montero at Rancho Cordova location right now...

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I can't imagine how to accomplish that. I mean, the logistics! Do you wheel in your own engine hoist? how do you get under the rig to remove the downpipes and unbolt the tranny? What do you carry the engine out on? A little red flyer wagon? I've been to a junk yard half a dozen times, some are dirt, some are paved, all are blazing hot. None of them let you drive in, or at least I don't think they do. Some of them put rigs up on "blocks" made of welded wheels, but not all of them. Getting under the rigs on those so-called blocks is pretty sketchy!

 

[vk_miniatures]

I'm talking about pick-n-pull yards. You pull parts off cars by yourself . They sell engines around $300-400 as is, but you have to pull it yourself. Also, those engines aren't tested or anything. Perfect for parts though. Also, good way to learn how to separate transmission from an engine . Oh and If you pull an engine from a wrecked car, chances are it might even run. There is a rolled over montero at Rancho Cordova location right now...

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I can't imagine how to accomplish that. I mean, the logistics! Do you wheel in your own engine hoist? how do you get under the rig to remove the downpipes and unbolt the tranny? What do you carry the engine out on? A little red flyer wagon? I've been to a junk yard half a dozen times, some are dirt, some are paved, all are blazing hot. None of them let you drive in, or at least I don't think they do. Some of them put rigs up on "blocks" made of welded wheels, but not all of them. Getting under the rigs on those so-called blocks is pretty sketchy!

They got big engine hoists there in the yard, wagons too. When you are desperate and have no money, anything is possible speaking from experience

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[Salonika]

Yes it is sketchy....desperation is a powerful motivator but I would hate to almost get the motor pulled but have to stop because of one stripped bolt, then have to come back the next day and find someone else plucked it from me.

 

[nwoods]

Resumed working on the 3rd Monty this morning. Drained the oil.....oh boy. There’s no oil in this thing! Literally just a dribble. The oil filter was welded on, so I removed the entire sump assembly, also mostly dry. Well, not dry, but no spillage due to no liquid quanties of oil. Crap!

 

[coffeegoat]

Yeah.. that's bad. The bigger question is did it all go somewhere - or did they forget to fill it.

If they forgot to fill if you may have a chance to get the old shop to reimburse you for something (new engine isn't likely but anything could help). Any obvious leaks?