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justinclark318

2016 YZ450F water pump (upgraded to Boyesen)

21 posts in this topic

Had my 2016 YZ450F boil over on a 90 degree day while trail riding. I did my best to shut the bike off when stopped, but at the end of the day it still got too hot. I ended up replacing it with the boyesen , which I have heard great things about. I was surprised to see that the OEM water pump was plastic and very small. Previous years it was aluminum. Wondering why they changed it up. Anybody else have overheating with the 2016s? I'll report back on how the boyesen is.ImageUploadedByThumper Talk1466831855.650839.jpgImageUploadedByThumper Talk1466831874.459202.jpg

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Nice bike! I know they are completely different, but my 02 426 would boil over all the time too, replaced the water pump with the boyessen high flow, and switched to engine ice. It can sit and idle all day long now and won't boil over. I think you'll be very happy with it.

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Nice bike! I know they are completely different, but my 02 426 would boil over all the time too, replaced the water pump with the boyessen high flow, and switched to engine ice. It can sit and idle all day long now and won't boil over. I think you'll be very happy with it.

Awesome! I forgot to mention I switched to engine ice coolant as well. Hopefully no more issues! Other than that, every Yamaha I have owned has been great machines.

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The problem isn't the water pump its the stock 1.1 cap. Buy a 1.6 or better cap and you'll be fine. 4 strokes get hot. I put a 1.6 cap on my 16 before i broke it in.

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The problem isn't the water pump its the stock 1.1 cap. Buy a 1.6 or better cap and you'll be fine. 4 strokes get hot. I put a 1.6 cap on my 16 before i broke it in.

Aww yes. Forgot about that too, I put a 2.0 on mine I believe.

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Sweet bike. I dig your number backgrounds. Care to share what and who made them?

I will be keeping my eye on this, hoping to pick up a new 450fx soon and have questioned the boil over. It gets hot here in Texas, and I generally try to not let that keep me from riding. I Never had an issue with the 100 degree temps while on my YZ250 2t.

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Sweet bike. I dig your number backgrounds. Care to share what and who made them?

I will be keeping my eye on this, hoping to pick up a new 450fx soon and have questioned the boil over. It gets hot here in Texas, and I generally try to not let that keep me from riding. I Never had an issue with the 100 degree temps while on my YZ250 2t.

Graphics are a mix of Decalworks and OEM. I think it's the T-4 kit. I had bought a factory effex trim kit at first and was disappointed with it because of peeling. The Decalworks have held up really well. Had them on previous bikes and they were great too. I kept the lower shrouds OEM on mine for now because I like the look. When they eventually get scratched up I'll put the Decalworks on.

ImageUploadedByThumper Talk1466966667.997737.jpg

ImageUploadedByThumper Talk1466966761.392982.jpg

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Your bike looks awesome.

I've been running a CV4 brand 2.1 cap on my WR450 with no catch tank and trudge through all kinds of slower off road stuff in the Florida heat with no issues. Recently picked up a Boyesen Supercooler for a little extra insurance this summer. But the 2.1 cap is money - had the 1.6 Tusk for a bit but moved that over to my woods YZ250 (which had no problems with heat to begin with).

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For anybody wondering, here's what the OEM plastic water pump impeller looks like. Well, at least what it looks like after I broke off most the fins trying to spin it off. Sometimes instructions are important I guess. It's molded onto the shaft, unlike the previous years where it was still aluminum and screwed on. Not really sure why they went away with the aluminum and went to plastic, but glad I have a much larger and stronger Boyesen one on it now.

ImageUploadedByThumper Talk1466967883.536817.jpgImageUploadedByThumper Talk1466967909.111301.jpg

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I had some factory effex on my YZ 250 and they seemed to not last as well as the previous decalmx ones I had on before. I like the factory look and will try to keep it that way.

Maybe they are trying to shed weight? Seems like the plastic would be more forgiving if you were to hit the pump cover? Who knows. But I will be curious as to how well you like the boyeson one.

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Anyone ever considered throwing one of these on?

Would end up being aprox 6psi higher than the factory 19.9psi cap.

ImageUploadedByThumper Talk1467768936.914513.jpg

Edited by mxrider4life847
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Anyone ever considered throwing one of these on?

Would end up being aprox 6psi higher than the factory 19.9psi cap.

attachicon.gifImageUploadedByThumper Talk1467768936.914513.jpg

 

Not exactly a calibrated thermometer....especially after a few hundred whoops....

 

Knowing how hot your water is information that you can't use....cause it's too late, unless you can speed up...unless  you like having a gauge you can't even read while riding...

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I ended up putting the 1.6bar on just for a little extra precaution, but I am hoping my temps should be much lower with the boyesen addition. I have a 3 day trail riding trip coming up next week so I should be able to put it to the test.

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For what it's worth, I just installed a Boyesen water pump in my WR450 this past weekend and I'm pretty impressed. Runs noticeably cooler but I think the 1.6 was a good move. I run a 2.1 on that bike for even more insurance way out in the woods.

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Anyone ever considered throwing one of these on?

Would end up being aprox 6psi higher than the factory 19.9psi cap.

attachicon.gifImageUploadedByThumper Talk1467768936.914513.jpg

 

 

Thats the cap i put on my 2014 YZ450f.  The guage is more or less a heads up to let you know if you should take a break. I put it on with the Boyesen Super cooler, and some Engine Ice.  Next ride out, no boiling.  I did notice that it still got hot a couple of times, but it cooled back down much faster, and dropping gear to let it rev a bit helped some also.

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Cool info. I think the 1.6 will be a good option as well. I am anxious to get into some tight track runs and try it out.

I don't plan on using the cap as a calibrated temp gauge. If I were wanting accurate realtime coolant temp readings, I would bring home my digital laser thermometer from work, a tool that is extremely accurate and very useful in troubleshooting aircraft systems. But not practical on the trail.

I do however believe it will be capable of giving some sort of ballpark range, during practice and getting to know the bike a little more. And certainly not something I will keep installed for races.

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Evans coolant, forget the high pressure caps and yes evans runs a bit hotter but you get a more consistent cooling, zero air bubbles=zero chances for extreme hotshots in the cylinder and head.  Plenty of naysayers but Ive used it for years and it just plain works!

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I wonder if the pressure cap temp gauge is at all accurate as most of the time it is in a hot air pocket. I run a Trail tech on my street supermoto 450 and the ambient air temp is way off. I suspect the water temp is way off as well.

 

I run straight anti freeze in three of my Yamaha 450's. The 16' WR450 came with a fan but it still has almost straight anti freeze little water. No higher pressure caps, no boil overs or Evans. But who knows I might try a higher pressure cap and a 70/30 coolant to water mix.

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I wonder if the pressure cap temp gauge is at all accurate as most of the time it is in a hot air pocket.

 

 

That's what makes me suspicious.  Temp gauges in car engines don't accurately indicate the engine heat as high as it actually is if/when there is enough coolant loss to put them above the fluid level, not even nearly.  The cylinder head is the best place for a thermal probe, and failing that, as near the head as possible in the water outlet to the radiator.

 

Something to understand about coolant vs. water: No coolant or mix of coolant and water removes heat from an engine as effectively as plain water does.  The problem is that no coolant or water can do anything to cool an engine if it isn't liquid, and engines have a well-established ability to boil almost anything put into them unless measures are taken to control that.  A pocket of steam instead of liquid over the combustion chamber is guaranteed to do nothing to help the engine live longer.

 

Pressurizing the cooling system to 16 psi (1.1 bar) as with a standard cap raises the boil point of water from 212 ℉ to around 230-235.  Mixing most common propylene glycol coolants 50/50 raises that to around 270-275 ℉, but there's a less obvious trade-off in that deal; the engine will be allowed to run up to 60-70 degrees hotter actual metal temperatures because of the increase in coolant temps and because of the reduced thermal conductivity of the coolant.  The coolant doesn't pull heat off as fast as water, but the idea was to keep the cooling system properly filled with coolant instead of having it turn to a gas and go away.  Give and take.  It's OK in that temperature range, but now think how hot you're going to let things get if you use a coolant like Evans that won't boil until 400+ ℉.  That's my problem with it.  And God help you if you're ever on the thing when a hose bursts.

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