KDXRIDER.NET

Hey yall,

I have just come to notice that by the looks of it, my base cylinder gasket is leaking coolant on the exterior of the case.
I have changed the oil multiple times after various different rides and am seeing no milky coolant which gives me the idea that it isn't getting into the case.

What I'm asking is what might be the best route in which to proceed to evaluate the status of the base cylinder gasket. I understand it will be some work (removing the head, detaching the carb, etc.) and pretty much two-thirds of doing the top end itself but am curious as to anyone's idea of just taking it apart just to put a new gasket on there.

I'd rather not spend the $$$ on the top end as it's fairly fresh but I guess I would also know the state of it by taking a look at it on the way down to the base cylinder gasket. I just need some justification for putting in the work to get down there without doing the top end while I'm at it is what I guess I'm getting at.

Photo's here:
https://imgur.com/a/zamd03G

If that is from coolant then you just gotta do it as that gasket is shot. By any chance have you done a pressure check on the cooling system to see/hear where the leak is? How many hours on the piston and is it cast or forged?

pressure test
vacuum test

or just take it apart and try throwing a new base gasket on there.

You can just change the base gasket, not much other than the cost of the gasket, coolant, and your time. If you're confidnt in the health of the top end it doesn't have to be redone just to change the gasket. You could pressure check, but you already know it's leaking so kind of just a redundant check at this point

Maybe I'm wrong about this as nobody else mentioned it but the coolant passages in the cylinder don't extend down to the base gasket, I just had my cylinder off last week, open to being wrong but I'm fairly sure

I appreciate everyone's input. I think its best I just go into the cylinder and replace the gasket and if need be do the head at that point. Cheers!

kdxdazz wrote: ↑08:15 pm Feb 15 2023 Maybe I'm wrong about this as nobody else mentioned it but the coolant passages in the cylinder don't extend down to the base gasket, I just had my cylinder off last week, open to being wrong but I'm fairly sure

You are correct. Good catch. Maybe it's weeping 2T oil/gas and not actually coolant. If it is coolant then that cylinder has a big problem.

SS109 wrote: ↑05:52 pm Feb 16 2023

kdxdazz wrote: ↑08:15 pm Feb 15 2023 Maybe I'm wrong about this as nobody else mentioned it but the coolant passages in the cylinder don't extend down to the base gasket, I just had my cylinder off last week, open to being wrong but I'm fairly sure

You are correct. Good catch. Maybe it's weeping 2T oil/gas and not actually coolant. If it is coolant then that cylinder has a big problem.

Thank you! Yall are right! (I have checked on eBay in regards to engines for sale/ cylinder removed to find out it is in fact just a gasket!)

You can see confirmation here. https://imgur.com/a/pLudPeu

That being said, is it just a gasket then? I'm not even 100% sure it's coolant so the spit out the side very well could just be that of a blown gasket and spitting 2T mix. Is there any probability that it could be coolant? How would that even come to be - All I can imagine is that it's the water pump seal/ bearing mixing in with trans oil but how would this even get up to be spit out the side as shown.

Appreciate yall!

The only way to get coolant to that spot would be if the cylinder was cracked. That said, I highly doubt it's cracked. Probably just 2T oil/fuel mix weeping out.

We are talking about the differences between oil and water here, chalk and cheese, just take a swab with a q tip and try mixing it with water, see if you get an oil slick on the water or it mixes easily, to replace that base gasket is a very simple task, you can even make your own base gasket, standard thickness is 0.40mm, most gasket paper is 0.50mm

kdxdazz wrote: ↑07:16 pm Feb 26 2023 We are talking about the differences between oil and water here, chalk and cheese, just take a swab with a q tip and try mixing it with water, see if you get an oil slick on the water or it mixes easily, to replace that base gasket is a very simple task, you can even make your own base gasket, standard thickness is 0.40mm, most gasket paper is 0.50mm

Ok, I’m going to proceed assuming it’s the gasket and get in there. I have a gasket kit so I’m ready to go.

That being said its being deemed “an easy task” from the videos I’m seeing it ain’t the easiest… or is it?

Looks as if everything connected to the top end has to come off to get at the base gasket. What about taking out the kips? Any help here would be greatly appreciated! Links or direction in fact

Yes, everything above the base nuts needs to removed. However, that doesn't mean anything within the cylinder so the KIPS assembly can remain. You only need to undo the pawl underneath the right KIPS cover. Remember, support the shaft like the manual says or you will bend/break parts. Also remember the nut is reverse thread as well!

SS109 wrote: ↑04:14 am Mar 26 2023 Yes, everything above the base nuts needs to removed. However, that doesn't mean anything within the cylinder so the KIPS assembly can remain. You only need to undo the pawl underneath the right KIPS cover. Remember, support the shaft like the manual says or you will bend/break parts. Also remember the nut is reverse thread as well!

Ok! Thanks so much, going to wait till I’ve got my new pipe in to do everything all at once.

I actually don’t have a repair manual, would you recommend Cyclepedia or where might I find one.

Cyclepedia will work but finding an OEM one on Ebay would be the best. That said, I bet there are probably a few good videos on Youtube covering how to do it.