[csdwarf11]

me and a friend picked up a vmax 600, the base gasket was leaking and it wouldnt hold coolent, so we took it a part and sealed it up, it doesnt leak anymore on the outside, but when it runs, it smokes so much, i mean alot,



we ran it for a bit and it didnt clear up, so do you think this is coolent getting into the cylinder?


what are the torque specs on the base studs, and also the head bolts,

thanks!

any input would be great

 

[csdwarf11]

i forgot to mention, be just took it apart, cleaned up the surfaces used a little silicone and tried it,


it smokes alot, but the snomobile responds fine and has power, i would expect it to bog out, and not run correctly, whats the best thing to test and do?

 

[SRX 700]

What do the plugs look like?

 

[csdwarf11]

well actually! heres another part of the story



we put premix down the holes to get it started, it would fire like onces and then we would have to take the plugs out clean them and do it again, every time it would go a bit more, till be got it running.


when we were taking the plugs out, there was oily orange antifreeze of them.


then after we go it running, it ran so well ,and started so well, first pull and idled and revved up great...( was just emitting plums of white sweat smelling smoke)

we never actually took the plugs out again. ill do that tomorrow


what should i look for with the plugs.

 

[aduck]

make sure theres no more antifreeze on em

 

[Yamaha440]

Did you put a new head gasket on it. not just coolant seals?

 

[csdwarf11]

I used no new gaskets, they were not torn or anything, maybe a little flat, but i used some silicone hoping to seal up the leak.


it did seal up the leak, there is NO fluid being lost outside of the sled, its just smoking about making me think its leaking into the cylinder.


does anyone know the torque specs for the base nuts and head nuts


i torqued everything to 25ish

i read that the head ones were supposed to be 24, but i couldnt find base bolts

 

[Yamaha440]

That is your problem, you always NEED to get new gaskets. Had this been a base gasket, you would have a hole in your piston. They aren't like new.

 

[yamadad4]

cylinder base bolts are 14ft lbs initial and finish at 24. the head bolts are 9 initial and 16 finish. torque starting on the middle 4 nuts in a crossing pattern working your way out to the left and right edges in a cross pattern then to the remaining 4 bolts for and aft again in a crossing pattern.

 

[csdwarf11]

you say, if this had been a base gasket i would have a hole in my piston right?


i took the head and jugs off, and didnt replace any gaskets.


the base gasket was the one leaking, i just took the head off to get at the bolts to the jugs.



what should i do, just not run it, order up a gasket set, and put it in? most likly problem solved?

i though it might be burning off antifreeze in the base, from sitting, i looked at all the bearing i could to make sure they wernt rusty, they looked good. is this possible?

 

[Yamaha440]

You should get new gaskets. If the base gasket leaks into the crank case, it will cause a lean condition, then when you open it up next time, there will be a hole in the piston. the gaskets are cheap insurance.

Here is a link to gaskets from Dennis Kirk: Snowmobile - Engine - DennisKirk.com

Here is a link to Yamaha parts and parts diagrams: Yamaha Parts, Yamaha Snowmobile Parts, Yamaha ATV Parts, Yamaha Motorcycle Parts, Yamaha Accessories at wholesale prices

 

[csdwarf11]

yeah i knew it wasnt good to run it because the gasket could leak, but we wanted to see if it would clear up, and it didnt seem to, so probably better just to get gaskets,


ive never actually burnt a piston, how hard do you have to be running it?

i realize that its the temp of the piston gets to hot, and just melts. but this couldn't happen at idle could it?

 

[Yamaha440]

IDK, but it's just better to be safe than sorry.

 

[csdwarf11]

yeah,for sure, order gaskets

~~~~also could it be a crack, im going to disassemble again while waiting for gaskets and inspect for cracks.


were is the most likely places for a crack, were should i look very closely?

could a crack leak, but be to small to be visible?


whats worse case senerio with leaking coolent into engine?

 

[Yamaha440]

It hit the skirt of your piston at temp, shattering skirt, scoring your jugs, wrecking your heads, then going into the crankcase, where it kills a bearing, then you have to get the crankshaft rebuilt at the factory for 1200. then the costs of new heads, boring, new pistons and rings...... The list goes on and on. Leaking coolant is a bad thing.

I can't see it being a crack, jugs and heads don't crack very often. The transfer ports could crack, but that wouldn't cause a leak with coolant.

 

[yamadad4]

worst case is ruining the bearings.

yes, you can seize pistons at idle. there is no set speed or run time.

i have never seen any of those cylinders crack, but its not out of the question. cracks may not be visible but will expand with heat, then leak.

 

[Yamaha440]

repeat post screw up..........****.

 

[yamadad4]

the factory doesnt do crank rebuilds, never have. independent shops will rebuild cranks for around $75, plus parts. you cant bore the cylinders, they are plated.

but none the less, as mentioned, the risk is not worth the gain.

 

[Yamaha440]

Well my uncle was talking about a crank rebuild and having to send it to the factory to get it balanced. :dunno:

 

[csdwarf11]

wow that sounds pretty awful, but i ment


without running the snowmobile , the fact that anti freeze is leaking into the cylinder when its running, what is the worst that could be wrong?


for example, the just is junk and i have to buy a new one off ebay, for 200$, or the base is cracked and thats so, much.

i mean worst case senario without further damage