1994 pickup making loud noise

[wayne3946]

My son is having a problem with his 1994 4x4 pick-up truck (104,000 miles on it). It was running fine and then when he cranked it this morning it started making a loud noise. The noise sounds like valves clicking extremely loud. The oil and water pressure gauges show normal and no check engine light has come on. When you push in on the clutch the noise gets a little louder. It's coming from the engine area, but does not sound at all like the noise his friend's truck made when it threw a rod. We want to take it to the shop but are afraid to drive it. HELP!! What could it be? I'm not very mechanically inclined so I can't do much as far as checking the engine.

Wayne

[Lakehaze]

Does it sound like a loud deisel? When the timing chain gets loose, it slaps against the timing cover (behind belts)and head. It's very loud and sounds kinda like all the valves are very loose.

Pull off the valve cover and look closely at the chain (very front of motor) and it's related compontents. There are two plastic guides for the chain as it between the cam and crank sprockets. The chain may have loosened long ago and has just eaten through the guides, allowing it to slap on the metal casing. You should be able to tell if a guide is broken. A failed chain tensioner is usually the cause of chain failure, but sometimes the chain just stretches and becomes too big and thus loosens.
You can probably dive it (if it is the chain) long enough to take it to a shop (at your own risk). If the chain snaps while the motor is running you will crunch you valves into the pistons (blown motor). If the chain lasts a long time, it (being steel) will eat through the aluminum cover and open up a hole to your presurised coolant system, spraying water into your oil.

[KimMG]

Since you are not mechanically inclined, I would recommend having it towed to a shop. Consider the cost of the tow as insurance against possibly causing serious costly damage. Don't know about where you live, but where I live a AAA membership almost pays for itself with just one tow.

[axekick]

Lakehaze is right. I have recently dealt with that problem myself, and the noise you described is exaclty what it sounded like. I have since completely rebuilt my engine which is probably not neccessary in your case, and there is nothing else that could quite make that sound in that engine. I actually drove mine for about three months like that until the chain wore through the timing cover and water began mixing with my oil. I continued driving it for a month after that until it started overheating and I finally rebuilt the engine.

[wayne3946]

Originally Posted by axekick

Lakehaze is right. I have recently dealt with that problem myself, and the noise you described is exaclty what it sounded like. I have since completely rebuilt my engine which is probably not neccessary in your case, and there is nothing else that could quite make that sound in that engine. I actually drove mine for about three months like that until the chain wore through the timing cover and water began mixing with my oil. I continued driving it for a month after that until it started overheating and I finally rebuilt the engine.

Thanks for all of the info and I did finally take the truck to the toyota dealership. They told me that the piston was hitting the bottom of the cylinder head and that it would be best to just get a new engine.
I looked at engine parts and justed wanted to know how much money I'd be looking at. Would I need the head, small block, or the whole big block. Also about how much would it cost to get the work done? I'd like to have some idea before I approached someone to fix it! Maybe it would be better to sell the truck like it is and buy another used truck.HELP!

[KimMG]

At a lot of auto parts stores you will find classified ads. Look through them for an engine importer. Japan exports cheap used motors with between 30k and 40k miles on them. In the San Francisco Bay Area I have purchased a couple of these motors for less than $400- and got a 12k or 12 month warranty.

[TNRabbit]

Originally Posted by KimMG

At a lot of auto parts stores you will find classified ads. Look through them for an engine importer. Japan exports cheap used motors with between 30k and 40k miles on them. In the San Francisco Bay Area I have purchased a couple of these motors for less than $400- and got a 12k or 12 month warranty.

Here are three sources:

www.orientengines.com

www.ebay.com search on "TOYOTA 3VZE engine" if v6, "toyota engine 22re" if 4 cylinder

www.engnbldr.com

Also check out www.yotatech.com for a LOT more information RE: 2nd generation Toyota pickups!