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Location:
Tasmania
Registered:
May 2002
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2TG rev problem
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Mon, 20 May 2002 14:15
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I still havn't found an answer to my 2TG problem. It used to rev to 7900rpm. Now it will start to splutter of valve bounce or something at 5900rpm, and won't want to rev much past that. Otherwise, power is good below this and it idles well. I am thinking a valve spring is colapsed or weak. I want new valve springs anyway, so I can rev better, closser to 8000rpm? Is this my problem, and can I change the springs without taking the head off?
Also, I can't take off with anything under 2200rpm. Is the idel rich or lean? I tryed bigger idle jets, makes it worse.
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Registered:
May 2002
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Re: 2TG rev problem
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Tue, 21 May 2002 06:08
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sounds like you got some problems. have you gone thru all the steps for tuning your carbies/checking your timing? if you check your spark plugs, see if they are sooted up or white. I don't think the 2TG's like runing rich anyway, but you don't want to run it too lean. one time i had mine running slightly too rich at cruise, fuck it was powerful! best idea is to get someone else to tune them, then fine tune them afterwards. replacing the vavle springs would be a good idea if you're gunna rev it up to 7900rpm 
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: 2TG rev problem
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Tue, 21 May 2002 07:02
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Just wonder if you actually have an electrical problem - high rpm missing might indicate a high tension lead prob. When I got my 2TG, it had this prob. I didn't investigate too hard but it resolved when I checked and replaced the coil lead.
Cheers Dave.
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Location:
Adelaide
Registered:
May 2002
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Re: 2TG rev problem
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Tue, 21 May 2002 07:59
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well if it USED to rev to 7900rpm, and now only revs to 5900rpm, then I think that the reving to 7900rpm may have caused you some damage for sure.. I did this to a 2tg, "over-revving" and it caused some extremely big probs, basically it broke the valve guides caused by valve bounce at high rpm and then the broken bits fell into the combustion chambers and hit the pistons, hence my rebuild...
but yeah I definately be getting ya head checked....(umm the one on the car I think) *lol* sorry, didn't realise how it sounded at first...... but as for revving upto and past 8000rpm, I dun think it's a good idea.... personally I wouldn't like to be spinnin round 8000 times a minute..... would you ??
but yeah, just from what I have been told by my mechanics about over-revving.
Brendon
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Club President
I supported Toymods
Location:
Sydney
Registered:
May 2002
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Re: 2TG rev problem
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Tue, 21 May 2002 12:54
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Johny if it was me I'd start with the basics !
First ingition then Fuel. Check you dissy is still advancing properly and the weights are still doing the job.
Definatly check your leads, Dizzy cap and rotor button. Also make sure you getting a good strong spark from the coil. If your running carbies the old fashon way of pulling the igniton lead and looking at the spark works fine ! 
If you picked up some shitty fuel or ave a blocked filter you will suffer a similar problem so check that as round two.
Then I'd do a compression test on the old girl and see what stories that may tell if you bent a spring or valve it should show up there all to clearly.
As for 8000rpm in a 2TG...Been there many a time Just make sure its set up for it first, In stock trim they do not like it !
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Location:
Tasmania
Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 08:14
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OK thanks for the help.
I have a 2T-GEU distributor, mechanical and vacume advance work. Rotor buton is ok. Cap is brand new. Leads are brand new TopGun, including the coil lead. Coil is a ND electronic sort with igniter, from a holden shuttle. Spark? It jumped out and zaped me when I was near one of the leads. Plugs are not too old, and look perfect, not carboned up or anything. Timing is set to 12 degrees, or 16 degrees.
Carbies were taken apart and fully cleaned out not too many kms ago. Carbies are tuned ok, except there is a dead spot under 2000rpm. Fuel filter is old, from the 4K! Will change soon.
Valve timing is ok, mostly in spec, 3 of them are 1 or 2 thou out. Compression is 137, 134, 120, 129psi. Not the best here, but it is idleing smooth and only has 8.8 pistons, and the hone job probably is not that great. (I was still learning at the time).
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Location:
Tasmania
Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 08:22
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I do have some mechaincal noise from under the cam cover! no too bad though, just a irregular tick tick. So do you guys thing I have damaged a valve guide? Ignition has to be ok. Would it be running out of fuel due to a blockage? That would be a cheap thing to fix. I think it is mechanical, like a colapsed valve spring.
Guys on the oldcorollas list are saying how their 4Ks will rev to 8000rpm with new stock valve springs.
I will pull the cam cover again, and take the cams and buckets off and have another look.
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Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 13:26
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hey rod,
you say that if he has carbies then the old spark to earth trick will be ok. Can you try this with electronic ignition or EFI?? my uncle came around and did this to mine when my coil went (may have got a couple of sparks out of the thing but). Would this have 'spiked' my computer? in the manual on electronic ignition it states to use earth sparking as a test, but not doesn't say anything about when using efi. I guess if i used a spark plug to the earth to see the spark it would be ok, but not straight to earth?!?!?
gotta love getting sparked by how many thousand volts off the buggas!! 
cheers
rob
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Club President
I supported Toymods
Location:
Sydney
Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 14:32
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Inferno,
Me and EFI are still getting to know each other but ANY stray spark has to be a bad idea ! You can actually get a thing that plugs into your leads so you can "Safely" check the Spark on an EFI vehicle. Don't know what its called or where to get it tho sorry.
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Club President
I supported Toymods
Location:
Sydney
Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 14:37
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Johny,
Your lack luster take of is most likely due to it being a bit rich at low RPM or that your carbies are too big. If could also be that your Jet to choke ratio is all out.
Could even be that your timing is to far advanced but at 12 degrees that should not be the case.
Definatly change your fuel filter either way that is a good idea !
Just out of Curiosity WTF is a Holden Shuttle ?? IS it a 4 Cylinder ? what is the dwell setting for it ? Is it the same as a 2TGEU ? If your dwell is wrong it will run like a Pig. Just ask Havoc !!
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Location:
Tasmania
Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 14:49
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I don't understand too much about dwell. A Holden (Isusu) Shuttle is a pasanger van 1982-1986? Is has a Isusu 4 cylinder motor much the same as a Gemini or Rodeo, 1.8 litre. It has NiponDenso stuff, and a magnetic distributor like a 2TGEU or any other Japanese NiponDenso thing. I think it is even the same distributor cap. The coil is a normal old oil one, used with a resister. I think it works good, dont think that is a problem. Not sure.
OK, I am running too rich down low, yes. How do I fix this? I think the venturi chokes are 32mm as standard. Jets are 125 mains, 150 airs, 55 slow jets. So I need smaller idle jets? Where do I get?
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Forum Sponsor
Location:
Shepparton (Vic)
Registered:
May 2002
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Re: 2TG rev problem
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Wed, 22 May 2002 21:14
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I would be having a good look at those plug leads. I used some Top Gun leads a couple of years ago and they sent spark everywhere except to the plugs.
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Registered:
May 2002
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Re: 2TG rev problem
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Thu, 23 May 2002 10:43
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Check your distributor shaft isn't loose/vibrating.
Rev it in the dark and spray a fine mist of water under the bonnet and look for sparks.
Good luck!
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Club President
I supported Toymods
Location:
Sydney
Registered:
May 2002
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Re: 2TG rev problem
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Thu, 23 May 2002 12:43
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Johnny
Mate seting up a set of carbies correctly can make all the difference. When Tina's engine was built it was tunned by ear as best as possible with the jets etc that were in them. then once it was run in a bit (750k's) we stuck it on Frank Kleinigs Dyno and he weaved his magic. I thought I was in the wrong car it was that much better !!! (Mind you the pink leapord print let me know it was definatly Tina's car ! )
If it were me and you can get someone who really knows ther stuff to sort out your carbies.
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