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So my 79 triumph 750 bonnie was running great.
I decided to change the oil (which i have never done)
I pull the drain plug with the screen thing on it, drained oil
I also plug what i thought was the drain plug but was a plug with a spring and a metal sleeve thing.
I drained oil from oil tank.
Put everything back on..
fill oil tank 3 qrts and put some oil in the crank case thru the inspection hole at base of cyclinder heads. about a pint or so.
started bike and went for a ride
notice my crank case breather hose which runs by my seat was hot.
then i noticed i was blowing oil out the breather hose.
It would normally blow a little then drip.
then I check the oil in tank and was pretty low...
bike was running hot
lost power..
put oil in...

what the hell did i do?
I hope i just foaled a plug or something.
Did i put too much oil in crank case?
Did i not put spring thing back in correct.

any and all info is a great help.
Matt
 

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the plug with a spring is the gearbox camplate plunger. If you unscrewed that, then you will have drained the oil out of the gearbox. The gearbox has separate oil from the engine, so if you didnt replace that oil (through the cap above the kickstart crank), I would suspect gearbox damage.
 

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You can run about 6 months on a dry gearbox.Was that 2nd plug underneath the gearbox,or on the timing case?

The oil return pump has stopped working;some small particle from around the drain plug has found its way into the pump.All your oil stayed in the crankcase.instead of pumping back to the tank.
Drain the crankcase again (expect plenty of oil).You can blow the rubbish through the pump with compressed air,if you're lucky.Do a search.I've covered this before.
Next time,just don't drain the crankcase;it doesn't help much (only 100ml of oil).
 

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Hmm,sounds more like you have managed to dismantle the oil pressure release valve.Did it have a big domed nut?
If the pressure release valve has been disturbed,...make sure it is assembled correctly before using the bike again.
Forgot to mention,...there is no need to top up the primary case with oil,..it only needs topping up if it has been drained by the screw at the bottom of the casing.The casing has been over filled hence the oil blowing out of the breather.
I would recommend obtaining a workshop manual for oil capacities.
 

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*Note... not familiar with the `79 model but:

What Dave said and 1/4 pint-ish into the sump is adequate.
Also 5/8 pint in the primary case. (after draining it)
The drain-plug with the mesh is the angled sump drain.
How much came out? Should have been about 1/4 pint. [unless its wet sumping]
The actual drain plug is under the main frame down-tube, opposite the filler.
Some of the pint (overfill) in the sump will be forced into the primary causing pressure that will be released via the breather.
Until the oil pump return evens the levels.
I think you lost oil from the breather,which left the overall level low.
Overfill is as bad as underfill.
I suspect the gearbox got very hot.
Hope this helps.
 

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1969 Triumph TR6C, 1973 Triumph T140V 750, 2021 Kawasaki H2 SX SE +
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Hmm,sounds more like you have managed to dismantle the oil pressure release valve.Did it have a big domed nut?
If the pressure release valve has been disturbed,...make sure it is assembled correctly before using the bike again.
Forgot to mention,...there is no need to top up the primary case with oil,..it only needs topping up if it has been drained by the screw at the bottom of the casing.The casing has been over filled hence the oil blowing out of the breather.
I would recommend obtaining a workshop manual for oil capacities.
It does sound like he did that but the oil pressure release valve (big domed nut) should be found on the right side/front of the case. Unless it was relocated in the late 70's but I can't see them doing that.
 

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http://classicbike.biz/Triumph/Triumph.htm

Matt,

Here's a link that has both repair and parts manuals. No '79 listed, but '78 is close enough for what you are doing right now. Take a look at the parts manual and figure out which plugs/bolts you removed as well as which plugs you poured oil into.

This will avoid everyone taking educated guesses at what you actually did and narrow down if you did any damage or just have a minor issue that can be corrected with some guidance from those with experience here, like Mr. Pete.

Don't mean to lecture, but suspect this was a learning experience for you. Don't venture into unknown territory unless you understand what you are doing first. That means having the manuals or someone to ask that does know. We've all said, "aw shnit" at one time or another. Welcome to the club. Order up a set of manuals. The learning/wrenching experience is just about as much fun as the riding experience. Maybe a little more for some.

regards,
Rob
 
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