Rad caps

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canyncarvr
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Rad caps

Post by canyncarvr »

I've been losing some coolant of late. Have yet to figger why or where it's going.

Tried a new cap recently. My last was an ND brand..the new one came from Schuck's. It was complete crap. I knew that when I bought it..but needed to get something. The gasket material in both seals was junk, 'standard' pressure..13psi.

Point of saying that part...if you're getting a cap, get a GOOD one. Caps from Stant seem to be OK.

..which was the next one I got. THIS one is 16psi. I've ridden with it once. Still lost coolant.

..but...also have a new telltale. A bit of exhaust spoo around a head stud.

I've heard 16psi is fine. I've heard 16psi will blow up stuff. Don't know about either of those points of view. I DO know I've never had a problem with a KDX head gasket..and I've also never seen any oily discharge (with an inability to control it) around a head stud.


Who uses a 16psi..has used one for awhile...and hasn't had any deleterious effect?


Thanks!

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Post by kawagumby »

Could the head gasket have been leaking some (mebbe not so recognizable) before the 16 psi cap was installed? That might help explain where the coolant was going, no?
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Post by canyncarvr »

>|<>QBB<
kawagumby wrote:Could the head gasket have been leaking some (mebbe not so recognizable) before the 16 psi cap was installed? That might help explain where the coolant was going, no?
Yep.

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Post by KarlP »

I've got a leaking radiator. It is such a small leak I can't find it but I can SMELL it. It smells like one of them new fangled orange 4-strokes trying to ride our single track.
It was caused by the clutch cable rubbing on the seam just below the cap. Different set up, I realize, but still a similarly aggravating condition. I filled the worn spot with epoxy and all was well for a while. I'm starting to smell it again.

I know for sure I wouldn't go to a higher pressure cap. Maybe a new, good quality cap, but not higher pressure. Unless I wanted to know where that smell was coming from sooner.....
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Post by kawagumby »

>|<>QBB<
KarlP wrote: It smells like one of them new fangled orange 4-strokes trying to ride our single track.
.....
:mrgreen:
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Post by Julien D »

I have no experience with 16PSI caps. I have a hard time imagining that an extra 3 lbs of pressure is going to bust anything in the KDX. It has that metal head gasket after all, not those little rubber o-ring jobbies. Have you thought about dumping some of that radiator UV dye in your rad so you can spot where the leak is? It works quite well, of course you need a black light to use it. I have a couple bottles of it around here somewhere.

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Post by canyncarvr »

Re: 'UV dye'

That's a good idea. Hadn't thought of it.

I don't know how little a bit of coolant you can run through the exhaust without a telltale smell or smoke..but I got none'a that. I suppose a UV setup would be more sensitive than what I think it don't smell.

I'll get it sooner or later. I'm not worried about it..more an annoyance than anything else.

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Post by Julien D »

Could be more than an annoyance if that leak is in a bad spot. If it did prove to be the head gasket, that water leaking into a hot combustion chamber can cause some nifty carnage. Seen it happen on a ktm 300. We had to have some pretty extensive repairs done to the cylinder and replace the head. Ouchie.... Of course, if that was the case the UV dye wouldn't do you any good anyhow. Unless it still shows up at the end of the silencer...

Hrmm.

You still have your overflow tank in place? Lots of folks remove them. I tried running without mine, and the rad was consistently low after a good ride.
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Post by IdahoCharley »

>|<>QBB<[quote="juliend"]Could be more than an annoyance if that leak is in a bad spot. If it did prove to be the head gasket, that water leaking into a hot combustion chamber can cause some nifty carnage. "...

CC- I would not take too long to dig into this problem. A leaking head gasket can cause head warpage and erosion at the head/cylinder interface where the leak occurs. IMO - fix the leaking head gasket problem then worry about radiator cap. Good luck - Charley
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Post by canyncarvr »

Re: 'You still have your overflow tank in place? Lots of folks remove them. I tried running without mine, and the rad was consistently low after a good ride.'

Yep. I do have it..and same thing here when I tried running without it.

IC: You're right, of course.

:cry: I don't want any carnage.


...even if it is nifty

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Post by Mr. Wibbens »

You guys are scaring me

I ran mine for a very long time with a leaky head gasket
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Post by canyncarvr »

Wibby's bike is different. When he last did a top-end..kids were born that now can vote. He ran coolant in his tranny for years, and nothing bad ever came from it. He'll run Canola 957...it's fine. He can run a loose and loosening shifter for a few years...and never rip off a spline or lose a shifter.

I wouldn't put a whole lott'a stock in what he's done and gotten by with. Your mileage most certainly will vary!

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Post by KarlP »

Wibby's bike is different. When he last did a top-end..kids were born that now can vote. He ran coolant in his tranny for years, and nothing bad ever came from it. He'll run Canola 957...it's fine. He can run a loose and loosening shifter for a few years...and never rip off a spline or lose a shifter.

I wouldn't put a whole lott'a stock in what he's done and gotten by with. Your mileage most certainly will vary!
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I've tried to ride his bike and can't. Everything is loose or falling off.
He's also fast as heck. Its cool to see him rattling right by a decked out poser in the tights and dissapear into the distance. :lol:
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Re: Rad caps

Post by Mr. Wibbens »

>|<>QBB<
canyncarvr wrote:I've been losing some coolant of late. Have yet to figger why or where it's going.

First of all, it would help if you'd INSTALL the friggen cap!! :wink:
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Post by Julien D »

I reckon a head gasket can leak in only 2 ways really. Leaking inside, or leaking outside. If it's an outside leak and not enough so that you notice it bein wet anywhere on the cylinder, UV dye would be your new best friend. If it was leakin inside, you'd probably know. I would think you'd have some white smoke and a smell of antifreeze from the exhaust. I wouldn't expect a small outside leak to cause any "nifty carnage" (tm?), unless you run it out of water.

I guess it could also be leaking both inside AND outside. That'd probably not be good....
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