I recently bought a 99 trooper 3.5 4x4 for cheap because of an engine noise it had. I figured what ever the noise was should be fixable for a couple hundo $$$ or at most a used engine for about 1500! But OH to my sorprise , took it to a tech and was told it was the crankshaft(500-700) or used engine (3-4000)which is out of the question. Can't find a reasonably priced crankshaft anywhere!!!! But after reading some of the posts here, I'm douting the problem is that. I guess I just want to be sure before I bite the bullet and buy the ferrari priced crankshaft! j/k So this thing made a super loud knocking sound. I mean it sounds like a tin can with a large rock bouncing inside it! Better said, like 6 tin cans with rocks in them! The tech did tear down the engine and showed me the crank but i can't realy see any major damage or maybe I don't know what to look for. So i guess the question is if anyone has had a similar experiance and what it ended up being.. Any suggestions welcome, Thanks!
oh yeah, the person I bought it from said it started making the knocking sound while SHE hehe was driving through Arizona but kept driving it al the way to TEXAS!!!!!! SOUTH TEXAS!!

 

I have that noise!!

We thought it was timing belt tensioner, but no.
Before I pull the motor, please tell me what it turned out to be.

thanks... best... pjh

 

it's funny that this is a very common problem with the trooper and no one could take the time to share their experience with me on this situation, but oh well. Anyways, so my issue did end up being a bad CRANK SHAFT. I took it to a machine shop and they told me the shaft was damaged beyond repair so I proceeded to buy one from him but his reply was "GOOD LUCK, finding one!" Anyways so after a while he simpethized with me and he recomended a place to buy a used one. Japanese engine imports ltd. Luckily, they had just switched out a motor for a trooper and they left behind the old one. He removed it and after close inspection we noticed it was spun or scratched. The machine shop guy had already schooled me on what a repairable crank should look like and so I noticed this one looked ok. The JEI ltd guy offered it to me for 50 bucks(guaranteed for unrepairable return) Keep in mind I had already ought one from ebay for 550 bucks but was refunded because they where out of stock, so I jumped on the 50 buck deal! Machine shop charged like 150 to fix and it is now at the mechanics hands. I also bought a new oil pump and the Trooper is supposed to be out this month...I'll update...I know I kind of told a long story here but I thougth I;d elaborate on how hard it was to find an solution for this thing! It's been at the mechanics for over a year now! boo huu

 

Thanks Eddie: I appreciate your input. No one's ever responded to my inquiries either.
I've got the front of the motor off of the 3.2 V6 in my 99 Rodeo, hoping to see a timing belt tensioner disintegrated (an internet tip). No such luck.
I was afraid it was connecting rod bearings... but it's the crank!?!?>!?!?!
OY.
There are 99'ish era Troopers and Rodeos all over the internet with that noise. Was there ever a service bulletin on these?
My truck is otherwise perfect.

 

well supposedly isuzu never cared to fess up to the issue. I talked to an Isuzu tech and he informed me that the problem was actually the oil feed holes in the cranks weren't designed well enough to feed the lube the engine properly! He gave me a solution for the issue that involved boring the holes in the shaft to a certain diameter but it seen a bit over my head and thought I'd just tell the machine shop to call him but I later couldn't local the tech who helped me that time..bummmer! Yeah other than the noise, my trooper was great! It's such a shame that at 70k miles this would happen...and I found a receipt in the glove box from the previous owner showing the oil pump had already been replaced @ 50k...I plan on getting this thing running and immediately getting rid of it or taking it to Mexico and using it as a weekend beater vehicle.Good luck with yours. As for it being your crank, if ur able to drop your oil pan enough to see the crank, u should be able to see the damage if u have someone turn it while u look. Well that how I inspected the used one I bought...of course the engine was out...

 

Thanks Eddie:
I'm taking my engine out. The truck's worth it, since Isuzu recalled the frame rot.

 

that's awesome, I had no idea about the recall on the rodeos! Well hope you get your Isuzu fixed and on the road! let us...or I mean ME lol know how it turns out !

 

Well, the Isuzu dealer has had the truck for almost three weeks. First he said he was going to make it safe for $250 and I'd have it back in a day or two... now he say he can't do a thing without taking the entire body off!
So, he said he's gonna take some pictures to send to Isuzu, and see if they'll do something.
If they buy the truck back, I'll be golden!
If not, I think I'm just screwed.
They recalled the doggone thing, but the recall was for frame rot that caused the trailing arm to come off... mine did, and almost killed me.
But now that I've had it fixed, they're gonna pay me back for the repair I had done, and try to walk away.
The deal with NHTSA was to fix the trailing arm problem, apparently not the rot that caused it.
We shall see...