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Trimatic shaky in a carby 202

1985VK

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Hey guys,

The trimatic shudders a bit when its cold and then comes good so i think it's a little low on oil issue. Anyone know how to check some ATF isn't being sucked out and burnt away?

Is there a line from the tranny to the christmas tree on the rear of the manifold that can let oil out into the exhaust? The g/f reckons the passenger sidewall of the transmission tunnel near her feet gets a bit hot on a long drive.

Is it the same line that comes off the vacuum modulator if it has pinholed or is it different? Can it be tested by sucking on the line or is there some other black magic trick?

Cheers
 

the_boozer

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if there's oil getting sucked thru the modulator line, the modulator would be rooted and it wouldn't shift right if at all is my thinking.
The exhaust is under the left side where the heat would be coming from? Is the flange leaking ? otherwise its too close to the floor unless you have extractors thats pretty hard to do, bend to exhaust too close to the floor it would probably bang on the floor when you tramp it if thats the case.
 

1985VK

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What if the modulator has a tiny pinhole and only a tiny amount gets sucked past the diaphragm until the gearbox finally gets a bit low on oil? Is there a vacuum line to the manifold that can be checked or tested for a leak?
 

vc commodore

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If it's being sucked into the manifold, you'll be getting smoke from the exhaust pipe....You can check the spark plugs for signs of burnt oil.

And you are assuming it is a low oil issue....Have you checked the oil level to confirm this is may be the issue?

Generally when the fluid level is low, you have gear selection issues when hot as well....
 

1985VK

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If it's being sucked into the manifold, you'll be getting smoke from the exhaust pipe....You can check the spark plugs for signs of burnt oil.

And you are assuming it is a low oil issue....Have you checked the oil level to confirm this is may be the issue?

Generally when the fluid level is low, you have gear selection issues when hot as well....

I am wondering if it is very minor oil loss and not part of piston chamber combustion.

It's odd, it can shudder a bit or maybe even lose gear temporarily when going around a corner and then it engages and then its fine. After that it drives and shifts fine, almost as if the oil loss is marginal.

When i find it is playing up like that and i add some oil the issue goes awayand it starts up and drives fine so i assume it oil level related. Just wondering if anyone else has experienced anything like that in a trimatic before?
 

Lacksballs

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1st: Check the oil level, smell it if it smells burnt or is discoloured (brown rather than bright red).

2nd: The modulator gets it vacuum supply from the inlet manifold, pull the line off and check to see if it "holds" vacuum if not the modulator is buggered. (The shift points will be all over the place as when vacuum is applied to the vacuum valve piston it shifts in its sleeve which tells the transmission if the engine is at idle <max vacuum> or WOT <zero vacuum>, so either holds onto the gear or shifts it sooner)

3rd: Check the coolant for oil contamination as the transmission used the engines coolant as it cooler via a tube in the radiator.

4th: Drop the trans pan & see whats inside, if there is clutch (friction plates) or metal material then its toast! You can simply adjust the bands if you have the correct spacer & an "inch-pound" torque wrench.

Or drain the transmission refill it with the correct fluid 2.3lts refill. And go for a cruise.
 

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Check fluid level - in drive at operating temp, check colour of fluid, if both good and still issues get a new (read reco'd) tranny. I have spent small fortunes trying to remedy a failing trimatic; most times it works out cheaper to get an exchange, and you get a warrantee with it also (usually 12 months).
 

1985VK

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Fluid looks and smells good. When i top it up it drives fine but eventually it needs another top up. It is a very slow loss of fluid and i just don't know if its weeping from somewhere or through the vac line to the tree on the manifold.
 
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Lacksballs

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Fluid looks and smells good. When i top it up it drives fine but eventually it needs another top up. It is a very slow loss of fluid and i just don't know if its weeping from somewhere or through the vac line to the tree on the manifold.

How much do you top over how many kilometres???
 

1985VK

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How much do you top over how many kilometres???

It varies. I might add 50 or 60 mls every couple of thousand kms. Its not a lot. If i add more oil it takes longer and depends on the type of driving so highway km's gets through it faster.
 
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