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Hi all, Have a 1993 trooper with a 3.2, that run and looks good.But why, Is the engine so noisy at the valve covers? it sounds like all the rocker arms are loose. Oil pressure is ok, no misses and it run grate. could this be that it needs valve adjustment? noise is less when engine is cold.
 

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No valve adjustments are possible, as this engine has hydraulic lash adjusters. Might I refer you to the Isuzu TSB on the subject:

http://www.nhtsa.dot.gov/TSBScans/sb614929.pdf

Before doing the stuff in the TSB, you might try a dose of Seafoam in the crankcase oil to see if perhaps varnish deposits are the cause of your problem ( www.seafoamsales.com ) . Also, be sure you're using no heavier oil than 10W-30, preferably 5W-30, and you'll see in the TSB the recommendation of synthetic 0W-30 oil !!!
 

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I too have had this problem, but it's seems more sporadic. A little background. I have a 95.5 Rodeo bought brand new. After the initial break in period I have run nothing but synthetic oil and have paid through the nose to change it regularly every 3000 miles. It now has 130,000 miles on it and still runs great. At first, it would start ticking at the end of the 3000 miles and I would change it early. For about the last 5 months, it does it off and on when it feels like it, even with fresh oils in it. It will go for days without doing it, then 2-3 days of doing it constantly. I read the service bulliten about the "varnishing" and did what it said (new oil, etc.). I have run "Seafoam" through it also. It has not stopped completely and it has me guessing as to what would cause this. Trash breaking loose and getting in the lash adjusters? Trash clogging up the 2 oil sensors on either side of the head?

I need some help please!
 

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I'm wondering if it might be the tensioner rather than the lash adjusters. If the tensioner was replaced during timing belt R&R I wouldn't be as likely to suspect it, but still a possibility.

Also wonder if you may have oiling issues; any degradation in oil pressure from new? You may have to tee-in a mechanical gauge if readings via the electric gauge are questionable.

Or, maybe the lash adjusters are plain worn out. They can be replaced, for around $9.00 ea:

http://www.importperformanceparts.net/i ... zuvt1.html

Good Luck...........ed
 

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Thanks Ed.....

I am starting to wonder that myself after reading other stories about it. Would it do it inter-mittingly? I did not hear it for the last 5 days and today it is doing it once again. Maybe a little more background information is need about the car. As mentioned earlier, the Rodeo still runs great with 130,000 on it. Maintenence has been almost nothing. Fouled a plug at 95,000 and changed them. 2 batteries and 1 starter, couple of sets of tires. I have never changed the timing belt according to the book because I felt "if it ain't broke, don't fix it!" It is a cream puff, been babied (changed the brake pads on all 4 at 105,000 and they weren't even half worn yet) and been an all-around great bargain. Basically all highway miles to and from work with a couple of trips from Texas to Alabama thrown in. But bottom line, I need to fix this because at times it sounds like I've thrown a rod. Then it goes away and it's just as quiet.

THANKS AGAIN

KC
 

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Change the belt and tensioner. It's very likely the tensioner is the cause of your intermittant noise. Pretty near every post I've seen referring to intermittant noisiness and making sounds like rods knocking is due to the tensioner.

Your service interval on the belt is 60K, good news is this is a non-interference engine so it won't kill the valves when the belt does go its separate ways.

Seeing as it's got the original tensioner, and the noise comes and goes, I'd take that bet.

Cheers............ed
 

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Thanks again for the info, Ed....

Do you know what causes it to make so much noise? Where is it located?

Is there anything I need to know about changing the belt and tensioner? Special tools? How long it should take? Cost of these items? What all needs to come off to get to it? And last, any short cuts?

You have been a great help in trying to get to the bottom of this and I want to express my gratitude.

Thanks again,

KC
 

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KC, check out this thread at the Outdoor Wire as I expect it'll answer most if not all of your questions. Recommend you get a good manual to guide you along the way, also.

http://www.4x4wire.com/forums/showflat. ... 14&fpart=1

If this thread doesn't do it all for you, use the forum's search feature and it'll turn up a grunch more on the topic.

www.stcharlesauto.com is a good place to purchase discounted Isuzu parts online.
 

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Belt tesnioners are very loud. Both of my '95s are/were very loud when temp was below freezing. The valves were quieter.
 

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I've also had this problem on my '96 Rodeo. Seems better after an oil change though. Sometimes it is noisy and sometimes not.

BTW-I had the timing belt replaced about 1k miles ago. Not sure if they replaced the tensioner or not though.
 

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I have a 95 Trooper with a 3.2 6 and a 5 spd manual. I bought it with 113,000 miles on it and at the time it wasn't making any noise. However, ONE WEEK after I had it the engine started making a noise like it had thrown a rod. I have read other posts about valve ticking, but this ain't no tick! My mechanic wants me to try Valve Kleen by Napa to make sure there is no trash clogging up the hydraulic lifters. If that doesn't work he says worse case scenario is a head job on the side of the engine that is making the racket. Does anybody else have any ideas?

Thanks,
Willie
 

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Willie, maybe it's time to get another mechanic! A head job on one side of a motor will NOT stop a rod knock!

Unless you have other signs of impending failure such as low oil pressure, look to the hydraulic tensioner (see my previous post in this thread). Many many have posted across most Isuzu forums that their knocking tensioner sounded like, or was diagnosed as, a rod knock. If you don't know the service history of this vehicle, you may well be at the point where the timing belt should be replaced anyway; do the tensioner at the same time.

HTH.........ed
 

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I think almost all Isuzu's have noisy valve trains. My wife's '97 Rodeo with 108K has sounded like a sewing machine ever since we got it, and my 94' Rodeo with 125K has started making an occasional ticking noise that came and went.

I replaced the timing belt on the Rodeo and checked the Belt Tensioner -- there was no visible signs of wear and it had plenty of strength -- not a thing wrong with it. I still had the ticking noise. I think replacing the tensioner is just a waste of money ($100 - $200) if it is in good shape.

It's my opinion that the hydraulic lash adjusters are to blame for the noises in all these engines. I think that they get gummed/varnished up or wear out and no longer function properly. It is probably just a case of poor engineering.

I did manage to get the Trooper to stop making the noise. 1. I used a quart of oil flushing juice (with kerosene in it) prior to an oil change and followed the instructions exactly. 2. I put in 10W40 oil (good heavy duty stuff that can take a lot of heat b/c I pull a trailer). 3. I put in a quart of Lucas Oil which I think is God's gift to man. This stuff is as thick as honey and has all kinds of goodies in it that improve lubricity and revitalizes things. It works it's way in places and sticks there so there's always lubrication. The noise has stopped. I'm going to try this on the Rodeo next and see how it works out.

Just a tip: if you haven't used the oil flush product before be PREPARED when you take the drain out of the oil pan and take the filter off -- the oil is extremely thin and runny and comes out with amazing force. I got it all over the place, even with a giant oil pan!

Michael
 

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My 2 cents- I think M. Wraight has it right. I've owned three Zu Rodeo 3.2s that as soon as I purchased them, I changed the oil to the recommended 10W30- and have followed the Haynes, Chilton recommendations, as well as the recommendations of Isuzu stealership "mechanics" regarding the use of 10W30 crankcase oils, and every time the engines ( perfect mechanically) rewarded my efforts with the ticking valve noise, however, EVERY time I switched over to 10W40 synthetic blends, The "noisy lifter syndrome" that seems endemic to these engines has faded into memory. Now, I live in Hawaii, and it's warm here all year 'round-so using a lower viscosity oil has no observable advantage for me. If you live where you encounter cold or freezing temperatures regularly, this probably is'nt for you. All I can say is after close to 400,000 accumulated miles on these three vehicles using 10W40 synthetics (a little more $-But worth it to me) I have NEVER suffered an oil related problem or malfunction, and the best part is my engines have'nt sounded like there are ball bearings rattling around under my valve covers since! But I still can't stress enough-Change your oil regularly!!(every 3000 miles) at least, follow the recommended maintenance procedures and change that timing belt, tensioner(As well as your Water Pump!) after 60,000 miles. Your Zu will love you for it!

ToddZ Kailua-Kona Hawaii
 

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I think that you can take the tensioner apart -- i remember looking down and seeing a snap ring down in there around the the shaft of the hydrualic arm. What you do after that's taken off is beyond me. You probably would have to refer to an official Isuzu shop manual for any info on that procedure -- it isn't in my Chilton of Haynes manuals.

I remember getting a price quote on one of the tensioners b/c I was considering replacing it with the timing belt after reading some of these forums. They are not cheap! I think NAPA wanted $150 for it.

As I said, I think it's a real waste to replace this every 60k miles. I can guarantee you if you had a timing belt job done at a shop (Isuzu or independent) they would not bother with it unless it is absolutely worn out. I never even heard of anyone recommending doing this until reading some of the forums here.

Put the tensioner in a vice and slowly compact it. You might be suprised at how much force that little thing has in it. In my opinion it doesn't get that much wear. It simply holds a wheel tightly against the timing belt to provide adequate tension. It doesn't have to move back and forth much and as long as the fluid never leaks out of the cylinder it will always be charged properly. It's not subject to the same kind of forces that the shocks on your vehicle are -- it just sits in this pristine, sealed environment pushing the little wheel against the timing belt -- not really a heavy duty job. If it has a lot of strenght left in it, I would leave it. I left the old one in my wife's Rodeo (109K miles) and I'm planning on leaving the one in my Trooper (125K) as long as it's still good.

And try the 10W-40 oil and maybe some Lucas Oil additive and see how that works out.

Michael
 

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Well, I've done two oil changes in the past 2k miles on my Rodeo. Last one I put 10W30 in. I think I may try 5W30 next. It is much much quieter now though. My engine was somewhat gummed up by the person who owned it before me so I'm changing the oil every 1k miles for the next 6 changes to see if I can clear some of that gunk out of there at the recommendation of my mechanic. Only has 67k on it now though.
 

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Why bother with the 6 oil changes every 1k miles?? If your mechanic is doing these oil changes you're only padding his wallet. It would be much more effective for you to buy some of the flushing fluid and do that before a normal 3k oil change. These flushing solutions contain kerosene and some other petroleum based cleaners that clean all the gunk out of the engine. It gets into gummed up oil passages and all tiny little places. Just oil alone is not going to clean out those nasty spots. The flushing fluid is very thin and it very good at cleaning up gunk. You usually put it in the engine right before an oil change and let the vehicle idle for 10 to 15 minutes. You change the oil right after that -- and it will be as black as crude oil straight from the earth -- but it WILL clean all the gum and junk out. Try that twice at 3k miles each.

Think of it like this: An engine gumming up and oil passages getting clogged is like a human getting clogged arteries and eventually having a heart attack (engine failure!!!). There are three ways to unclog the arteries. 1. Reroute new arteries around the clogged ones (a bypass) 2. Mechanically clean the arteries (a stent or angioplasty) 3. a TPA, or clot buster - a solution that thins the blood and dissolves clots. HOWEVER -- no clogged artery has ever been cured by draining the person's blood and replacing it with fresh blood at short intervals!!!

I know that oil has detergents in it specifically designed to remove gum and sludge deposits, but it is really only effective if it can flow through something at pressure and basically scrub/dissolve. If the parts are so gummed up that oil can't get through or to them, then it's a waste trying. The solutions in the flushing fluid dissolve sludge much better than the detergents in the oil, then they thin the junk out and hold it in suspension.

I used a motor flush and my oil is 90% cleaner after just one shot! Try this, you might be suprised. Changing your oil every 1k miles is just wasting oil and making the oil companies a little wealthier!
 
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