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Water pump weeping '04 525EXC

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So, my '04 525EXC has had intermittent leakage from the weep hole for quite a while. Never lost any measurable amount, just leaves a small stain. Finally decided to change the seals and holder, but no improvement. Pulled it apart again. Seems there is some wear on the camshaft where the seal rides, but it is so small, it's nearly imperceptible.

Anyone else have this issue or know a cure without replacing the cam?

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I had the same issue. I had a machine shop turn the end of the cam down and sleave it with stainless steel. so far no problems but did have to reinstall the carrier/seals to stop the leak. I followed everyones advice to the letter but still had a weep. so far it looks good though. Be meticulousness about cleanliness during reinstalation. a tip I recieved but didnt try is to press the inner water seals in a hair further into the carrier so they are not riding on the same grooves they made before.

I live in Cambodia so the machine work was $10 . I would imagine its cheaper to buy a new hotcam than to have the original machined in the states but who knows. Try pushing the seals in further. Just make sure they stay parallel so you dont wear another groove into the cam.

I have the opposite problem with my Rad cap. it constantly weeps fluid. any tips to fix that?

Good luck

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same thing for a weak cap is to get a new one. But I start by cleaning it well, clean the mating surface in the rad neck-sometimes it gets corrosion built up there. The sliding the seal in further is a good idea for the grooves. I do the same thing on a counter shaft seal when the bushing is grooved, works every time.

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Mine started weeping again. so Frustrating. is this something I should just expect to live with?

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Mine started weeping again. so Frustrating. is this something I should just expect to live with?

1) If the groove is deeper, start with a 220 wet/dry sandpaper, smooth to touch and finish with scotch pad. That covers the shaft as best you can.

2) Clean the steel camshaft ring. The carrier 'o' ring seats here for oil separation.

3) Stagger the seals (in the carrier) a few thou or .mm's to get out of the groove.

4) Aneorobic sealer insures an 'o' ring seal against the case for oil and on the AL carrier for sealing coolant.

5) No on mentions the carrier seating flush in the thousands of WP seal complaints. Use the snap ring pliers as Trav shows in his video to install the carrier w/seals over a shaft protector. I never could get it seated flush with snap ring pliers.

6) Use of a socket or even PVC tube to drive the carrier flush against the head/cap seam is needed to seal inside carrier surface. This also squares the carrier seals to the shaft. The carrier now fits square.

7) Replace parts & ready the bike for fill

8) Let the sealer set up over night before refilling for the test ride. A quick mention for head and rad bleeding to finish the job.

I did a bunch of these before I caught the carrier hanging up without seating. That made the difference for my bike. Don't get discouraged. A number of KTM's are on the trail with a WP stain courtesy of their dealers or local shops.

You can do the job as good or better.

51531.jpg

Permatex® Anaerobic Flange Sealant Flexible, gasketing material for use on rigid machined flanges with less than .015" gap. OEM approved – use where OE’s specify “anaerobic” gasket (cures in the absence of air). Withstands temperatures to 300°F (149°C). Eliminates preformed, pre-cut, paper, rubber and cork gaskets. Flexes with flanges that move in service. Suggested Applications: Water pumps, thermostat housings, transmission pans, transmission case covers, transaxle casings, engine cases, timing covers, and o-ring replacement Item # Container Size Pack Part # MSDS TDS 51531 50 ml tube 10 51531 51580 300 ml cartridge 10 51580

Automotive stores have it. Lasts in the tube a long time.

Note for the chronic counter sprocket leak. Try a 25.00mm X 2.00mm X 29.00mm metric O'ring from specialty hardware stores or hydraulic shops. Fits better than the 25.12mm X 1.78mm KTM stocker.

Edited by Burnrider

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good advise above although i had 225+ hrs on my first 520 with the stain in place! wept for four years until i rebuilt it.

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1) If the groove is deeper, start with a 220 wet/dry sandpaper, smooth to touch and finish with scotch pad. That covers the shaft as best you can.

2) Clean the steel camshaft ring. The carrier 'o' ring seats here for oil separation.

3) Stagger the seals (in the carrier) a few thou or .mm's to get out of the groove.

4) Aneorobic sealer insures an 'o' ring seal against the case for oil and on the AL carrier for sealing coolant.

5) No on mentions the carrier seating flush in the thousands of WP seal complaints. Use the snap ring pliers as Trav shows in his video to install the carrier w/seals over a shaft protector. I never could get it seated flush with snap ring pliers.

6) Use of a socket or even PVC tube to drive the carrier flush against the head/cap seam is needed to seal inside carrier surface. This also squares the carrier seals to the shaft. The carrier now fits square.

7) Replace parts & ready the bike for fill

8) Let the sealer set up over night before refilling for the test ride. A quick mention for head and rad bleeding to finish the job.

I did a bunch of these before I caught the carrier hanging up without seating. That made the difference for my bike. Don't get discouraged. A number of KTM's are on the trail with a WP stain courtesy of their dealers or local shops.

You can do the job as good or better.

51531.jpg

Permatex® Anaerobic Flange Sealant Flexible, gasketing material for use on rigid machined flanges with less than .015" gap. OEM approved – use where OE’s specify “anaerobic” gasket (cures in the absence of air). Withstands temperatures to 300°F (149°C). Eliminates preformed, pre-cut, paper, rubber and cork gaskets. Flexes with flanges that move in service. Suggested Applications: Water pumps, thermostat housings, transmission pans, transmission case covers, transaxle casings, engine cases, timing covers, and o-ring replacement Item # Container Size Pack Part # MSDS TDS 51531 50 ml tube 10 51531 51580 300 ml cartridge 10 51580

Automotive stores have it. Lasts in the tube a long time.

Note for the chronic counter sprocket leak. Try a 25.00mm X 2.00mm X 29.00mm metric O'ring from specialty hardware stores or hydraulic shops. Fits better than the 25.12mm X 1.78mm KTM stocker.

Great tips. especially "driving the carrier in with a socket." Mine just keeps wanting to creep out at a slight angle which is what caused the wear in the cam in the first place. I have permatex liquid gasket #2. Do you think that will do the trick? We dont really have specialty automotive products here in Cambodia yet. I used grease on the last install.

Thanks again

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Yes, should be fine. Coat your 'o' rings, install the carrier and give it overnight or longer to set before putting the impeller and cap on it.

The anaeorobic sealer is more consumable in an engine. If you apply excess sealant it will not harm an open bearing because it stays pliable. Some sealers tend to harden, they can be used safely if applied with care.

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