rattely 3tgte

**tosh** · 03-04-2006, 07:17 PM

I have been hearing a noise from the front of the engine, it does not always make it but when it does its pretty loud. Seems to be there right through the rev range, then next time you start it no noise at all. It is starting to get progressivly worse so its time to fix it. I suspect timing chain? can it be re-tenioned or do I replace the lot??

**tricky** · 03-04-2006, 07:53 PM

A timing chain tends to make a 'slap' sound. You can retension your upper chain (The tensioner is the big arse nut shaped thing hanging off the side of the head), but the lower chain has no adjustment. It's hard to diagnose noises without actually hearing them, but timing chains can be pretty loud, and bearings are usually more of a 'thud'. Does the noise stick around when the engine is warm?

**camshere** · 03-04-2006, 07:58 PM

3T-GTE has (from memory) and oil filled tensioner, so its loose normally and when you start it the oil pressure tightens it up. If you start the car and it's rattely and then quietens down, and is quiet on subsequent it could have failed. If it rattles all the time it could just need a small amount of adjustment using the timing chain pre-tensioner on the front drivers side of the engine. (Its like a hexagonal knob with a rubber dust seal around its base protruding from the head) This can be adjusted by screwing it in or out and testing the preload with the sprinloaded button inside it (push it with a screwdriver). Just make sure you don't overtighten it or it can do real damage to your chain. If you need better instructions check the web, i think there are some out there, or PM me and i'll see if i can dig something up on this one. Failin that it could be your actual timing chain could be worn to the point where the tensioner is no long effective.

In addition to this the GTE variants of the 3T have a series of timing chain guides that are basically a flat piece of metal with a plastic(ish) coating that stops the chain slapping about in its longer sections - this will create a fair amount of noise and additional wear on the chain if the plastic layer has worn down. Hopefully these aren't a problem as I've heard they are frightingly expensive - personally I'd look at the tensioner and chain first for your answers.

**tosh** · 03-04-2006, 08:39 PM

it seems to make the noise hot or cold, I might try to tenison it, I have tried once before but I had no idea how the system worked. The only info I could find gave a chain sag distance to mesure when you hung a weight off it. To hard with the engine in the car. So any info on how to check the chain tenison would be awsome.

**tricky** · 04-04-2006, 10:54 AM

There is a plunger in the middle of the tensioner. You test the preload by pressing on this plunger with 3-5kgF, and the deflection should be 0.5-1.0mm. If it is more, undo the lock nut and tighten the tensioner. Secure the locknut and check again. If you cannot tighten the tensioner sufficiently, your chain and guides will be stuffed. This costs a bit, because most of then are NLA, and the ones you can get (genuine) have to come from Japan. There are a few companies around who do aftermarket equivalents.

Yes, the tensioner is oil filled, but this is as a dampener. The tension is set by the internal spring preload method documented above.

BTW, I hope it is the tensioner for your sake!

**tosh** · 06-04-2006, 01:16 PM

Something else that I had noticed That when it rattles it also pings realy badly, I tried turning down the boost (15 to about 10) but it didn't seem to make any difference. I assume that the dizzy would be thrown out by a loose timing chain???? And what do I use to mesure 3-5 kgf with to ajust the tensioner with? One other problem (I have many) is I seem to have trouble getting it to idle but only some times, It seems like a vacume leek but it only happens every now and then. I am running a microtech MTX8 an I suspect the problem lies with the vacume line to it some were. any ideas??

**RiceburnaGTV** · 07-04-2006, 06:06 PM

Just a suggestion but try checking the water pump man,they can get pretty bloody loud and grindy when forked and its only a couple of bolts to take it off.

good luck

**The Witzl** · 07-04-2006, 06:41 PM

STRIP DOWN!!!!

yeah i'd be looking at the timing chain.... when they go they make baaaad noises!

**23T-GTE** · 07-04-2006, 08:44 PM

last time i looked for 18R-geu timing chain guides they were ridiculaously expensive, but still available if u want to pay, i think i got them from stewart wilkins rallying in NSW, they also stocked 3T-GTE parts (japanese aftermarket) to my amazement, so maybe google them if u want to check prices for timing gear.