3T-GTE Dilemmas

[ben5072]

I have a 3TG in my TA22 at the moment which I have had for years.
However I have never really driven it as it has never run properly since I have owned it!
Only recently I had the timing cover off to fix a mad timing chain noise only to discover that the exhaust cam had been a couple of teeth out all these years. Don’t really know how it was running!
Turned out the crazy chain noise was a set of straight cut timing gears that I didn’t know about. Bonus but they are noisy little fuckers!
So after reassembly and getting the cams back in alignment this time, I took it for a test drive which resulted in the engine fucking itself.
Bent #1 exhaust valve and jammed it open!
Turns out the exhaust cam being a couple of teeth out had been causing the exhaust valves to be rubbing up the face of the inlet valves for all these years causing all the exhaust valves to be bent slightly but still seating fine! Go figure!!!!
So somehow me realigning the cams actually managed to spin the #1 exhaust valve around out of its seating possie and bend it some more. Don’t really know what happened!

So I decided to do a head swap off my spare engine that I picked up cheap.
But after removing the head off my parts motor I discovered that it had had a fresh rebuild and a set of forged pistons were hiding in it to my surprise.
It had fresh honing marks, gaskets, new oil pump and all. So we then decided to do an engine swap.
I just spent a shit load of time and cash painting, polishing, and re-gasketing the entire engine only to drop it in and find out that it has a major case of blow-by. It runs like my 2-Stroke! I was hoping the smoke was because the engine was that fresh the rings hadn’t bedded in yet but it appears not.
It has an insane amount of crank case pressure. I’ve had to plumb both the cam cover breather and engine block breather down to the ground to stop it belching smoke out the exhaust for the mean time. Instead it comes out under the car. It actually leaves 2 snail trails on the ground if you hit boost! Ahhhh!
So I did a compression test on it and got 140psi compression in #1 and #2 and 50psi in #3 and #4. WTF!!!!!!!
I did a wet test on it and it brought the comp in 3 and 4 up to 100psi. So from what I know that mean it is the rings rite!

If the engine has all the signs of a fresh re-build why would I have bugger all compression on 2 cylinders? Could they have F’d it up, is there any other possibility?

Broken rings, wrong wrings, ring gaps wrong??????????
Cracked block?????????????
Cracked head, Head Gasket, ???????????

Can anyone help me out hear please?

Because at this point I’m getting really pissed off because I’ve spent months in the shed and now I’ve got 2 fucked engines! At the moment I’m trying to decide whether to chuck some exhaust valves in the head on my old worn out engine with the straight cut gears in it or to dive into my new fresh engine and do the rings! I hope!!!!!!

Shit sorry for all the yabba but I really need some feedback!!!!!!!

Cheers Guys

Ben

[3jcelica]

Ben,

You have nothing but bad luck. It sound like that engine has to come out. Difficult to tell what the problem is with cyclinder three before you get the piston out. As I said the pressure you have on the other three is very good for a 3tgte.

I have had engines that have sat for a long time and the rings stick in the bores. So hopefully thats all it is.

I think you have done all the testing you can with the engine without inspection.

Pray that the #3 forged piston is still ok.

Why is it that whenever you pull something off you find little gems inside your engine. I however would be fairly wary of the cam timing gears that you have.

Happy to swap my engine for both yours

Roger

[79GT]

that sux mate, BIG time.

i guess what you have to contemplate is, wether you just want the car driving, or you want the car DRIVING. getting the rebuilt motor running, will be your best bet, not neccesarily easiest, but you will thank yourself for it in the long run.

although if you are that frustrated take up rogers offer. bolt it in, and drive into the sunset.....

good luck mate. hope you get some better luck. Jamie.

[ben5072]

Yeh I keep getting lucky by finding bonus bits inside my engines but then everytime it seems to keep turing around on me and biting me in the arse!

Yes Roger I don't trust the timing gears either because they seam to coarse more headaches than benifits. They are just so noisy and It is very hard to tension the top chain correctly (as they only replace the bottom chain). The slightest adjustment and the engine will become rattley when loosened, or the idle will drop down and bog the engine down when tightened. Can't seem to adjust it correctly. Thus they are not going in the new engine! New engine runs sweet besides the obvious!
Cheers for the offer of the engine swaps Roger but I recon I mite just persevere with what I'v got! LOL nice try tho!!!!!!

Jamie hows your 4T running now, havn't had many drammas with it? How long have you had it in the car for?

Come-on who else has some feedback for me? It would be greatly appreciated!

[3jcelica]

Ben,

I was suggesting the engine swap half in jest, did not expect you to go down that path. The engine you have in their will be sweet once you put all that other gear you have onto it.

Your problem will be the rings, either stuffed or stuck in the piston due to sitting for a long time. I have heard of people having just rebuilt their engine, fill the radiator up with water before starting the engine (note head gasket not sealed and) water potentially going down the bores and siezing the rings. Hence no compression, this can happen over night.

When you do pull it down coat everything with liberal coats of motor honey or stop smoke, this stuff is thick and won't drain away as fast.

Roger

[79GT]

hey Ben, 4t is running real good, its just all the other issues with the running gear that i have to deal with now. its only been running since late august, and still i am getting changing and repairing little bits and pieces....(note, diff pinion seal sucks the bum)

although that being said my 4T is a bit rattly, but i believe this is mostly due to my horribly experience of a burst oil line....soo devo...compression is still all good, but now has a little more character. . so it will be up for a rebuild at some point in the future, but still runs like a dream. never misses a beat.

mmmmmm motor honey....

[mad1600]

Hey Ben. My thoughts are rings stuck in pistons after sitting or broken. Unlikely to be end gaps as all cylinders would probably have met the same fate and comes good on wet test. I'm afraid it's pull the pistons and have a look mate. Re-ringing this engine sounds by far the best option and only about a days work(should come out the top if just been bored/honed as there should be no lip)
Goodluck!

[Draven]

tear down, inspect, rebuild

[ben5072]

I hate my life!
http://i342.photobucket.com/albums/o...2/IMG_0560.jpg
http://i342.photobucket.com/albums/o...2/IMG_0561.jpg
Who can spot the huge hole in my pistons?
Can anyone tell me if they are actualy forgies, cos now im not sure they are?
Got to run will update at a later date

[ben5072]

I can’t believe I was actually running this engine in my car for a couple of weeks! 2 of the pistons literally fell apart in our hands when we pulled them out of the bore.

I have just realized that my 2 blown pistons have different casting marks underneath them to the 2 that are still good. Although they are physically the same piston. They also have different gudgeon pins in them.

The blown 2 have (F - M) on the underside and the good 2 have (S) which is inside a small shield logo. Does anyone know if this is a manufactures mark at all because I would be keen to just replace the 2 dead ones. Was definitely not counting on dead pistons!

How do I tell if they are forged? I thought if they have machining marks on them they are, because I know the standard ones don't. They must be though because who in there right mind would replace blown cast pistons with a new set of cast pistons if they blew the old ones. But how do you actually blow a hole in the side of a brand new piston in a fresh engine. It’s all bullshit damnit!!!!! I have seen a few standard ones which have broken the ring lance under to much boost, but not to the extent mine have. Actually gone rite through the piston. Could they just be cheap arse pistons?

I really have no idea about the engine though because it came as is from Japan as a misc. engine. The other dodgy thing is they have used 2T rod bearings because the oil holes don’t line up with the 3T rod and cap holes. Pardon my bad terminology I’m a carpenter not a mechanic. Ha ha, I’m learning really fast at the moment! So they have had to re-drill new oil holes in the bearings, seems dodgy as to me!

So where is the best place to get a new set of pistons and at what cost? I still don’t have access to the Classifieds Forums on Toymods for some reason I have restricted access.

Cheers Fellas

Ben

[mad1600]

Ring lands usually break due to excessive pinging(maybe running on poor fuel or too much boost) or rings are incorrect for piston and don't fit properly.

[ben5072]

Cheers, well I got no idea what has happend because the engine was allready F'd when it arrived in the country. Dodgy Japs, sell us all the crap they don't want anymore!!!!!!!!!!

Discovered my blown pistons were not forged hence the result. Infact they look to be very very cheap poorly made aftermarket pistons probably for a 3tc. They have absolutely no meat in the top of them making them very thin around the ring lands, instead they have steal strengthening plates on the sides to make them heavier to make up 4 the lack of alloy. They also have extremely large slits accross the sides of the piston to feed the oil rings instead of small holes. This is why they shattered. It tore a hole in the piston between the oil ring feed slots and rings lands, not even 2mm of meat there. Not even the standard ones have these poor qualities!

Has anyone seen shity pistons like this before?

I'm trying to source some real forgies now! I contacted Wiseco and can get a set of K547M87 for $900. Has anyone bought a set of these, do I need to get them fly-cut? These are 2mm oversized, is it worth going larger, you can get up to 4mm oversize.

Can anyone recommend any other brands, how do prices compare?

Also does anyone have a set of good 3TG exhaust valves lying around that they want to sell because I still need some for my old engine?

Cheers in advance
Ben

[3jcelica]

Ben,

You can also get pistons from the states.

from either of these places

http://paradiseracing.com/Store/

or

http://www.brdracing.com/

The exchange rate is not working in your favour.

Keep in mind that you will need to get your rods modified to suit the pistons as any forged piston you get will require floating gudgen pins

Roger

[ben5072]

Just thought i'd chuck up an update for anyone trying to source 3TG forged pistons for a resonable price. Im passing on the whole idea for a while, gotta get my house built and stop blowing cash on my toys!

Australian Distributer of Wiseco Piston Kits: $724 trade price + postage!
part # K547M87 - 2mm oversize
Serco Motorsports
108-114 Steel Street
Capalaba Qld 4157
Ph; 07 3362 6600
Fax: 07 3362 6610

Or when the Ausssie Dollar gets back up there-

Paradise Racing
http://paradiseracing.com/Store/
Arias $475US + $65US post

BRD Racing
http://www.brdracing.com/
Wiseco $439US + $48US post

Cheers Roger for putting me on to them.