Coolant leak

Hey, just remember. There is a logical explanation for any problem.
You just have to find it. This one shouldn't be that bad.
 

Tell us more about the middle cylinder that was blown ?
Did you get one new cylinder and replace it and use the 2 original good ones ?
Possible that one (or the 2 originals) were decked ?
Have you run a good straight edge across the cylinders ?
We just got a Mountain Max 700, that had the tops of the cylinders slightly decked, and 2 base gaskets..
So, anything is possible.
 
Tell us more about the middle cylinder that was blown ?
Did you get one new cylinder and replace it and use the 2 original good ones ?
Possible that one (or the 2 originals) were decked ?
Have you run a good straight edge across the cylinders ?
We just got a Mountain Max 700, that had the tops of the cylinders slightly decked, and 2 base gaskets..
So, anything is possible.

Took everything apart, had the crankshaft rebuilt (bearing toasted),
replaced every parts in the water pump
got a used cylinder and piston that was in good condition and yes reused the 2 other one, but new rings on all new circlips, new needle bearings....
new fuel pump, new gas tank filter
new gaskets
new carbon reeds
new carb kits
new power valves kits

I did use a straight edge on the head at different place as well as on the cylinders and all seem to be perfect, straight.....
 
I did use a straight edge on the head at different place as well as on the cylinders and all seem to be perfect, straight.....

I'm guessing it cant be straight somewhere.
Unless you have a couple bolts that weren't doing anything, something has to be off, and it wouldn't take much.
 
I'm guessing it cant be straight somewhere.
Unless you have a couple bolts that weren't doing anything, something has to be off, and it wouldn't take much.

I will verify meticulously again.... and wait for the new set of bolts. kind of stuck without them for now.
 
Thank for the offer/assistance!!!

I ordered new ones earlier today, should be on my door step early next week. in the meanwhile Ill have the straight edge back on to see if I did not miss a spot
 
UPDATE!!!!

So I finally received my new bolts for the cylinder head. Torq it in 2 steps as mentioned in the service manual, this time I went to 35 of torq, and again coolant all over :o|

Tried the opticool gasket as well as the Yamaha and both time all cylinders get some coolant and it leaked into the pipe, half a cup in no time.

placed a straight edge on the head and the cylinders and all seem straight.....I dont know what to do anymore. really discouraged.

Trying to be logical; If the head was bent or the cylinders not straight would I not have a leak of coolant seeping outside where the head seal with the cylinders???

IMG_6324.jpgIMG_6323.jpgIMG_6321.jpgIMG_6322.jpg
 
You must have a cylinder coolant jacket cracked in the area around the exhaust port. Keep the head on. Pull exhaust and refill the motor and see which cylinder is dumping the coolant from the cylinder.
 
You must have a cylinder coolant jacket cracked in the area around the exhaust port. Keep the head on. Pull exhaust and refill the motor and see which cylinder is dumping the coolant from the cylinder.

Ok! trying that today....
 
Don't forget Copper spray!!! The stuff really works. You should find Copper at any auto parts store.
 
[video]https://www.facebook.com/695656993/videos/vb.695656993/10156975517136994/?type=2&theater&notif_t=video_processed&notif_id=1587763386566359[/video]

This is what happening..... Any guess??? any idea???
 
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Ive never seen troubles like this. I hate to sound like captain obvious. Are just the two cylinders PTO and MID leaking? Is MAG leaking?
I can only imagine four scenarios for coolant out the exhaust.
Head gasket failure.
Cylinder base gasket failure will cause the same coolant leak up the transfer ports.
Head is warped or cracked.
Cylinders have coolant jackets cracked.

I hate to see ya replacing parts that are not broken. You might just have to. Ebay has a couple of heads $49/59.
I'm betting its a head or base gasket leaking. Did you replace the base gasket? Copper spray both gaskets.
 
Ive never seen troubles like this. I hate to sound like captain obvious. Are just the two cylinders PTO and MID leaking? Is MAG leaking?
I can only imagine four scenarios for coolant out the exhaust.
Head gasket failure.
Cylinder base gasket failure will cause the same coolant leak up the transfer ports.
Head is warped or cracked.
Cylinders have coolant jackets cracked.

I hate to see ya replacing parts that are not broken. You might just have to. Ebay has a couple of heads $49/59.
I'm betting its a head or base gasket leaking. Did you replace the base gasket? Copper spray both gaskets.

MAG does not seem to be leaking, at least not as bad as the others...

head gasket failure, I think I can eliminate that one. I tried with both new original one and new opticool, I doubt both new would fail....

head does not seem wrapped (straight edge)on it look good. But micro cracked, ya maybe...

cylinders jacket cracked... The middle one was blown so purchased one from ebay to replaced it. Would suck to have been sold something broken...

new base gasket but no copper spray. sometime ill put some permatex red spray stuff on some gasket, but dont remember doing anything like that on the base gasket.

Ill take all cylinders out to begin with I guess and now so many coolant leaked while trouble shooting that I am afraid that it made it way in the base...
 
UPDATE

I removed all cylinders and looked down in the base and it was full of coolant. I hooked a piece of gas line on a shop vac and sucked all of it, approx 2 full cups...

When I rebuilt the engine (my first time attempting a rebuilt) I did removed the water pump shaft to replace some parts; bearing and seal if I remember or maybe just a seal..... but I definitely changed something. Can it be leaking from there by seeing the amount of coolant down there?
 
Just throwing this out there, could you drain the cooling system and refill with just enough coolant to fill the water pump cavity and spin the motor over again to see the results? Could this help identify whether it's a leak from the cylinder base gasket and not the head gasket? Only other area's that come to mind is the mechanical seal on the water pump shaft (behind the impeller) allowing coolant to leak into crankcase, but you would think all 3 cylinders would spray coolant out and the carb heating circuit (unlikely).
 
Ooops! Too slow on my response! Try filling the hose connected to the waterpump with liquid and see if it's entering the crankcase.
 
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Ooops! Too slow on my response! Try filling the hose connected to the waterpump with liquid and see if it's entering the crankcase.

ya that what I was thinking to. I was just wondering if it was ok to do it with water? with all that try and error I ran out of coolant...

and then after just suck it all with the shop vac ...
 
Thats alot of coolant. I dont think its a gasket.
I would turn my sights on what was done with the water pump.
 


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