desertgasser300
Banned
+1 to you guys.
2010 EC 300 Water pump shaft snapped & bearing collapsed
- Thread starter justsam
- Start date
StuJohnson
New member
Go figure....
Here is one other link I know of....
http://2tracing.it/ricambi-gas-gas/motore/kit-modifica-pompa-acqua-maggiorata-ec-300/
Jakobi
Super Moderator
I just butchered a checkpoint impellor by trying to lap down the cooling fins (square them off). Its a no go, so if you're going to do it do the way that GMP suggested and have someone machine from the back.
Does anyone know how much extra shaft hangs out once the seals are in? It wouldn't be hard to lap a couple mms off the shaft itself, or alternatively run a spacer between the gear and the inner race of the bearing in the case. With both you'd have to ensure the impellor doesn't contact on the back side then.
Anyways, I'll email Matt at checkpoint and see if he can update his design.
Does anyone know how much extra shaft hangs out once the seals are in? It wouldn't be hard to lap a couple mms off the shaft itself, or alternatively run a spacer between the gear and the inner race of the bearing in the case. With both you'd have to ensure the impellor doesn't contact on the back side then.
Anyways, I'll email Matt at checkpoint and see if he can update his design.
Jakobi
Super Moderator
Would have taken a bit more than 0.5mm to get mine to clear Glenn. I don't even think a second gasket would have managed to clear the checkpoint on my 2010. Never the less you are right with your solution. Its the quickest, easiest and most effective method. I was just throwing thoughts around.
StuJohnson
New member
Well that sucks....
I have a Checkpoint on my way now. I actually called and spoke to Matt today and he indicated his impeller is a good 2 mm taller than the OEM one..... Well how is that going to work?
I may be returning it and back to the OEM one.
Glenn -- your idea seems so easy but not sure exactly how some of us could do it when don't have access to the proper tools.
Jakobi
Super Moderator
It was. I can post a pic of the two side by side if you want. The height is not so much the issue as I thought it was, as the fins come to a point and should in theory also fit into the pump casing. The clearance issue is the location of the entire case. Either machining the casing out further, using a spacer, or removing material from the rear of the impellor are the way to do it.
I emailed Matt and explained the issue today so hopefully he'll be able to simply recess them a bit more on the back for us. Like you Stu, I don't have the tools to do it properly so tried to work from the other side. Reality is that I just trashed a $50 part. Either take it somewhere that they can do the recess for you, or just bung enough gaskets in to get the clearance you need.
GMP
Active member
Just take the side cover off with the pump intact. Install the Checkpoint impeller. Mount the cover and note fit. Use shim around the bolts between the pump cover and side cover to determine required clearance, or even shim stock, old feeler gauges as long as its placed evenly, be accurate (not plain washers). No gaskets just snug the cover down lightly. Every time you do this check the clearance by spinning the shaft/gear from the rear. When there is no longer any interferance, measure the thickness of the shim stack that was needed. Now you have your MINIMUM TOTAL required clearance. Now, either remove this from the rear of the Checkpoint impeller, or make up an alloy spacer plate, but you want to add .3mm to .5mm for a buffer. So, you can do this in several ways:
Single OEM gasket with modified impeller
Cut additional .5mm from impeller and use ThreeBond, etc.
Add .5mm to measured clearance for plate thickness and use ThreeBond(why keep buying two gaskets?)
Its not that big a deal. Take the measurements, take the part to a shop and your done. The plate can be made in the garage easily with a dremel and a few files if you choose that route. Don't try to modify the blades as Jake found out.
Single OEM gasket with modified impeller
Cut additional .5mm from impeller and use ThreeBond, etc.
Add .5mm to measured clearance for plate thickness and use ThreeBond(why keep buying two gaskets?)
Its not that big a deal. Take the measurements, take the part to a shop and your done. The plate can be made in the garage easily with a dremel and a few files if you choose that route. Don't try to modify the blades as Jake found out.
cladoo
Site Sponsor
I will try to get some from Gas Gas Pacific and have them for us Albertans!
Thanks Claude !!
2011 250, my plastic impeller was just slightly rubbing on the cover. I just got the engine back from dealer and he had installed an alloy impeller as I requested (cover not installed for better access to engine mount). When I check the clearance with the cover sitting against the impeller (no gasket), there is ~.020" space. This would require two stock gaskets minimum.
I have some .060" cork so I'll try that as I expect it to compress to about .045" for a gap of .025". I've never had any cooling issues and my engine temperature stays low.
I have some .060" cork so I'll try that as I expect it to compress to about .045" for a gap of .025". I've never had any cooling issues and my engine temperature stays low.
GMP
Active member
Check your cover in the center around the hole. There may be rough casting there that the alloy impeller hits that the plastic would not. You can work this out and smooth the area if needed. I had to do this once fitting an LTR impeller to a GG125 with an older cover.
This is not surprising, look at the kit from MotocrossCenter. Their plate is quite thick, and the impeller appers only slightly deeper than the Checkpoint part. The cover is a sand casting with only limited machine work, so lots of room for improvement there. Getting a close fit with the alloy part is going to be a custom job as described.
Neil,
So you are approx .5mm. A 1mm gasket or spacer plate would set you up fine.
This is not surprising, look at the kit from MotocrossCenter. Their plate is quite thick, and the impeller appers only slightly deeper than the Checkpoint part. The cover is a sand casting with only limited machine work, so lots of room for improvement there. Getting a close fit with the alloy part is going to be a custom job as described.
Neil,
So you are approx .5mm. A 1mm gasket or spacer plate would set you up fine.
The cover is quite good inside and would only take a bit of polishing to clear the plastic impeller.
I should remove the alloy impeller and machine the back side, but I'll leave it alone since it's already mounted. No point in taking a chance on damaging the plastic gears if some bolt torque transfers into the shaft. Cutting a new gasket is easy enough. I have some stiffer .040" gasket material that may be ideal for this job.
Measuring some stock gaskets shows that they start out at .020" and compress down to ~.015" after assembly.
I should remove the alloy impeller and machine the back side, but I'll leave it alone since it's already mounted. No point in taking a chance on damaging the plastic gears if some bolt torque transfers into the shaft. Cutting a new gasket is easy enough. I have some stiffer .040" gasket material that may be ideal for this job.
Measuring some stock gaskets shows that they start out at .020" and compress down to ~.015" after assembly.
Vindicator
New member
MotocrossCenter water pump kit arrived yesterday:
The 2 gaskets are 0,5mm each and the aluminum spacer is 5mm
The old impeller is ~13,5mm and the new one is 18mm height . This leaves a gap of 0,5mm on the spacer. Because we need to use 2 gaskets (1mm) , I would say that when torqued adequately we might end-up with ~1mm of extra gap.
Preliminary testing shows no contact with the cover. I'll see if I can find some shims to put between the shaft and the impeller to measure overall gap.
The new seal on the left, the housing has 1mm more than the old one:
But this is what's really troubles me:
The used one is at the center, the others are new but none of then is correctly centered... There's small differences that will make it wobble like in previous video . This should not be like this... Any alternatives ?
The 2 gaskets are 0,5mm each and the aluminum spacer is 5mm
The old impeller is ~13,5mm and the new one is 18mm height . This leaves a gap of 0,5mm on the spacer. Because we need to use 2 gaskets (1mm) , I would say that when torqued adequately we might end-up with ~1mm of extra gap.
Preliminary testing shows no contact with the cover. I'll see if I can find some shims to put between the shaft and the impeller to measure overall gap.
The new seal on the left, the housing has 1mm more than the old one:
But this is what's really troubles me:
The used one is at the center, the others are new but none of then is correctly centered... There's small differences that will make it wobble like in previous video . This should not be like this... Any alternatives ?
Last edited:
Vindicator
New member
The new impeller, shaft, bearing and retainer in place . Also a new plastic gear on the other end.
I used a 1,5mm shim (don't have any lower) between the impeller and the shaft and I could hear it gently scratching the cover. I added another and with 3mm I couldn't even close the cover. My best guess is there's at least 1mm gap with this setup. Just to be on the safe side, I will throw another gasket on the cover.
I used a 1,5mm shim (don't have any lower) between the impeller and the shaft and I could hear it gently scratching the cover. I added another and with 3mm I couldn't even close the cover. My best guess is there's at least 1mm gap with this setup. Just to be on the safe side, I will throw another gasket on the cover.
desertgasser300
Banned
I really dont want to open the pump cover on the 12', im afraid I might find this!
It also looks like McMaster and Carr has a listing for the spring seal. Just don't know the size of it?
http://www.mcmaster.com/#mechanical-seals/=mlwmby
It also looks like McMaster and Carr has a listing for the spring seal. Just don't know the size of it?
http://www.mcmaster.com/#mechanical-seals/=mlwmby
