Milky grey oil on the tops of pistons? GT550 1976

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rderrick121
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by rderrick121 »

[quote="barney01"] [quote="Alan H"]

Quick questions, I have photographed what I think is the "front" of the motor. Just to make sure you are referring to the side that has the exhaust pipes on it? I would upload the picture although I am not sure how. I am gonna make a trip to the gas station soon to pick up some diesel. I see now that my oil pump is leaking my 2 stroke oil like a faucet, good thing I only filled the tank with a bit of oil. I can see the leak is coming from what looks to be the base of the pump, anything that regularly goes bad here? I have striped the screw that holds the top cover on and am going to have to be creative to get the cover off... Also, what is the best way to prime this pump up? I can see that there is oil there because the lines are clear but how do I know if its actually getting to where it needs to be?

Just to make sure we're on the same page, in a 2 stroke the top of the piston and case connect in a way that dumping something into the top of the motor through the plug hole (and turning it over) gets it to the oil in the bottom. Therefore this diesel strategy will require another oil change as well? Thats not a problem just making sure, but wouldn't I also have to drain the diesel from the case through the oil drain plug?
Thanks again.
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Alan H
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by Alan H »

I think that firstly, you need a manual and do some reading. There is no oil in the bottom of a two stroke engine (like there is in a four stroke). On a Suzuki, the two stroke oil comes out of the two strke oil tank to the pump, then to the crankshaft and, main bearings and inlets. It does its job, then is burt and the residue is ejected out of the exhaust - that's why a two stroke smokes. You will need to remove the cylinder heads (they are cast as one piece) to do this properly.
I did mine with the engine on the bench so that access was easier, and draining the diesel was also easier. If you just pour diesel through the plug holes, most of it will run straight out again. I'll have a look for my original description of the process.
Proof that four strokes are over complicated
barney01
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by barney01 »

The pump cover definately has to come off to give access to the 3 screws that hold the pump down. Then you can lift the pump but be careful there is a pin in the shafts that is easily lost. The leak is probably the six rubber o rings that sit between the pump and the spider. No problem these can still be bought. Whilst the pump is off use an oil can to charge the lines to the engine.After the new seals are on replace the pump and screw down tight. The pump has a bleed screw on the top to remove air from the tank line feed.
I agree that to clean the engine properly you need to lift the barrels it's not that difficult really but get some head and Base gaskets before you do.
Here is a video to help you with the oil pump.
https://youtu.be/necW4LnXBHM
Yes front of engine is exhaust side
Look here for parts your side of the pond
https://www.partzilla.com/catalog/suzuk ... indy-gt550
Last edited by barney01 on Mon Dec 17, 2018 9:13 am, edited 2 times in total.
NO SMOKE .......NO POKE
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Alan H
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by Alan H »

Alan H wrote: I'll have a look for my original description of the process.
Here 'tis.

Basically, take the heads, barrels and pistons off and fill the crankcases with deisel. Turn the engine over steadily a few times - over a couple of days -and drain the dieselout. I did this a couple of times over a week or so, and kept turning the engine every day. It softens the seals and any rust on tbe seal rubbing faces and also cleans out the main and big end bearings. After the last drain off, over oil all the bearings with 2 stroke oil and drain any excess out. It'll be pig to start, so use a set of hotter plugs initially - I used a squirt or two of easy start as well. Once it starts and runs ok, and the smoke clears(!), you can go back to standard plugs.
This worked for me on the 550K and the current 550A rebuild has had similar treatment.I believe it's the rust on the seal rubbing surfaces that is the main culprit fot problems, rather than just dry seals, so it's worth a try for the sake of a couple of quids' worth of tractor blood
Proof that four strokes are over complicated
teazer
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by teazer »

When it sat for all those years, was it inside or outside and were the exhausts and carbs and airbox all in place? Does it look like it got wet in all that time?

The reason I ask is that it sounds like the crankcases are full of that oil and water. The oil probably leaked down from the oil tank and water came in from somewhere.

If that's te case, there is a high probability of rust damage to the crank. I would remove crabs and exhausts and lift the head and barrels and flush the bottom end out with diesel and then see what you are working with.
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slosher
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by slosher »

You would be amazed even condensation within the motor the effect it has when mixing with oil, has it stood in a cold climate :?: Even UK weather caused my TL gearbox oil turn milky around the filler plug one year.
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rderrick121
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by rderrick121 »

Hello all, thanks for all the help! In the following couple of days I will get the diesel in the block, gasket's ordered and all that good stuff for the flush. Any insight to the torque pattern and specs for the head?

Our climate is 50/50 summers are 70-80 winters are 0-40 I think it stayed dry in the shed, no dripping on it or anything but I can't say it wasn't humid.
barney01
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by barney01 »

NO SMOKE .......NO POKE
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slosher
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by slosher »


Barney that's a bostin manual where did you get it much better than Haynes :)
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barney01
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Re: Milky grey oil on the tops of pistons? GT550 1976

Post by barney01 »

Here is the whole thing http://www.3cyl.com/mraxl/gt/manuals/gt ... ntents.htm
Bear in mind it is for the early models with separate carbs but most of it is relevant.
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