Jump to content

500 EXC Water Pump Seal

Recommended Posts

I have recently replaced a water pump seal on my brother's 13 500 EXC.  Last year I had to replace the same seal on my 13 500 EXC.  Is this a common issue with motor?  It seams the design is a little suspect.  I have used the OEM replacement kit on both bikes.  I was unable to find any aftermarket upgrades for the water pump assembly.  Any thoughts?

Share this post


Link to post
Share on other sites

One of the reasons I run a 70/30 (coolant/distilled) mix with prestone is for the seal lubrication.

 

Do you seen anything that's weak in the pump design?

 

I have bikes with over 110,000 mies with that type mixture, the ktm is pushing 28,000 mile

Share this post


Link to post
Share on other sites

One thing I don't have an answer to, but a concern.  The oem impeller is a near weightless piece of plastic, what happens long term when you put a heavy aluminum Boysen impeller on there, which that shaft also serves to the counter balancer?

it makes ne wonder, usually I don't change from oem, unless there's a good reason. Like the plastic ones don't hold up and the other doesn't cause longer term issues.

Share this post


Link to post
Share on other sites
15 minutes ago, Spud786 said:

The oem impeller is a near weightless piece of plastic, what happens long term when you put a heavy aluminum Boysen impeller on there, which that shaft also serves to the counter balancer?

Heavy aluminium - have you actually weighed a plastic & alloy impeller ?

I think after 45 years Boyesen would know their stuff

Share this post


Link to post
Share on other sites
2 minutes ago, S.O.A.N.Z said:

Heavy aluminium - have you actually weighed a plastic & alloy impeller ?

I think after 45 years Boyesen would know their stuff

No I haven't, but Im generally skeptical of all aftermarket, till proven other wise, Ive only bought a boysen product once, about 30 years ago. I was disappointed, so I might dispute they know their stuff.   They are just one of many after market companies to me.

Share this post


Link to post
Share on other sites
8 hours ago, Spud786 said:

No I haven't, but Im generally skeptical of all OEM products, as they must 'sell' us a new product every year, and a cost benefit analysis usually tells them not to make any mechanical changes to the current design, no matter how flawed. Aftermarket companies typically make their living on solving problems that the OEM manufactuer chooses to ignore. Boyessen, R&D racing, JD Jetting, TM Design works, Scotts, etc, all take the end product considerably more seriously, and are much more conerned about their reputation than there market share. OEM manufactuers are working on the next model year to use 4 to 7 years earlier, and MUST bring product to market, no matter the issues.

 

fixed it for ya

Oh, and yes, that seal is pretty marginal at best. You should replace the impeller shaft at the same time, as the wear on the shaft will not be visible. You can prove it to your self by mic'ing the shaft for wear. Boyesen's design is an actual update in performance and durabilty, and it highly recommended.

Share this post


Link to post
Share on other sites
4 hours ago, Krannie McKranface said:

fixed it for ya

Oh, and yes, that seal is pretty marginal at best. You should replace the impeller shaft at the same time, as the wear on the shaft will not be visible. You can prove it to your self by mic'ing the shaft for wear. Boyesen's design is an actual update in performance and durabilty, and it highly recommended.

Boyesen makes a water pump impeller and cover, but that's not the real problem.  The seal is poor design.  Hoping there would be something better out there.  Unfortunately, it sounds like a PM every 100 hours now.  That's about when they both went out.........

Share this post


Link to post
Share on other sites
58 minutes ago, JVP said:

Boyesen makes a water pump impeller and cover, but that's not the real problem.  The seal is poor design.  Hoping there would be something better out there.  Unfortunately, it sounds like a PM every 100 hours now.  That's about when they both went out.........

Im pushing 600 hours, and I know people with near 800 hours, and haven't heard this issue on the 2012's+, with the water pump seal.

I am alittle bummed the 500's don't seem to have a weep hole, so the only hint of a seal leak may be coolant in the oil.

might be an issue with the counter balancer taking out the seal, and or bearing. Since they share the same shaft.

Edited by Spud786

Share this post


Link to post
Share on other sites
5 hours ago, Krannie McKranface said:

fixed it for ya

Oh, and yes, that seal is pretty marginal at best. You should replace the impeller shaft at the same time, as the wear on the shaft will not be visible. You can prove it to your self by mic'ing the shaft for wear. Boyesen's design is an actual update in performance and durabilty, and it highly recommended.

I know the RFs motors had issues, but not seen the newer 500 motors develop the same issue, atleast till this thread.

Share this post


Link to post
Share on other sites

Yeah, my 520 RFS motor ate seals like candy. Haven't heard of the newer motors being prone to it.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×