bottom jugs still leaking water after replacing gasket

[drake1]

ok i have a bad water leak on the bottom of the jugs, i removed the engine and replaced the gasket and it still leaks water with no pressure, i pulled the cylinders again and put Permex Ultra Gray on both sides of the gasket, i know i am not supped to use gasket maker since there are gas fumes in the crank but dont really see any other choice. if this doesnt work what would be my next step, i know the jugs cant be machined since the cylinders stick out of it but would removing the crank shaft and having the top of the case machined help or is warping mostly in the jugs? second if i did have it machined would that be enough to have clearance issues with the pistons then? not sure how much is normally taken off
thanks jeff

 

[Guest_User]

ok i have a bad water leak on the bottom of the jugs, i removed the engine and replaced the gasket and it still leaks water with no pressure, i pulled the cylinders again and put Permex Ultra Gray on both sides of the gasket, i know i am not supped to use gasket maker since there are gas fumes in the crank but dont really see any other choice. if this doesnt work what would be my next step, i know the jugs cant be machined since the cylinders stick out of it but would removing the crank shaft and having the top of the case machined help or is warping mostly in the jugs? second if i did have it machined would that be enough to have clearance issues with the pistons then? not sure how much is normally taken off
thanks jeff

pictures would help a lot here... if there is porosity or minimal corrosion, depending on the surface it can be filled with 2 part epoxy like JB weld. clean and prep the area well, mix up the epoxy and apply, then drag a razor blade across the surface to get as flat as possible, when cured, check to see if it needs and light sanding...

but, I`m just guessing since I can not see the condition of the surfaces... if they are badly corroded or cracked most likely they will need to be replaced...

 

[Dr Honda]

If you have a small warp or crack... you CAN'T use an RTV product. The lower half has pressure, and fuel. RTV likes neither of those. The only thing that may save you is using ThreeBond 1211 or 1194.


is this an 800 engine?

Last thing.... I can't say I've ever seen a Rotax case warp. There just isn't that much heat in the lower half. And if it did get that hot... there are going to be other issues.

Normally, a water leak is caused from water freezing in the jugs, and the damage/issue will be there. Also... if you have to top of the engine case "Decked", and the issue is in the jug... then it wont' help anyway. Basically... the engine needs to come apart, and EVERYTHING needs checked.

 

[drake1]

update, i was just told by a local dealer the hylomar made by permatex is recommend to use with the flanges and is also gas safe or double up on the gaskets...is this worth a try? i just did the squish test and i am at 2.4mm with a 6mm gasket... i need to have 1.2 to 1.6mm so must have a high spot but this is one both pistons so now i have no idea what to think other then i need more torque but i did to 180 like the book said. i did replace the pistons with wsm platniums whilei was in there. even going to at 1mm gasket that brings me to 1.7mm
this is a 787 engine

 

[Guest_User]

update, i was just told by a local dealer the hylomar made by permatex is recommend to use with the flanges and is also gas safe or double up on the gaskets...is this worth a try? i just did the squish test and i am at 2.4mm with a 6mm gasket... i need to have 1.2 to 1.6mm so must have a high spot but this is one both pistons so now i have no idea what to think other then i need more torque but i did to 180 like the book said. i did replace the pistons with wsm platniums whilei was in there. even going to at 1mm gasket that brings me to 1.7mm
this is a 787 engine

what was the outcome with your leak?
any pics?

 

[Dr Honda]

what was the outcome with your leak?
any pics?

He hasn't logged in since October 7th. He had another thread about "Bad WSM Pistons". He was basically blaming the pistons for the engine not running right.

In that thread... he was mixing measurements... posting wrong sizes... and generally made no sense. Let's face it... if you are building an engine... and are looking for help... you need to post all the correct info. Because of that... I think I pissed him off trying to get the real story. AND... I basically blamed him for trying to band-aid a F-ed up engine. (He made mention that there was still a leak)


Besides... now that I see he suggested that he may "Double up" the base gasket.... now I know why the pistons had a large deck height. He may have said he had a 3 dot gasket in it... but now I wonder if he had two, 3 dot gaskets.


You can read it here:

http://www.seadooforum.com/showthread.php?56554-wsm-pistons-really-are-that-bad!