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??idles up and down, LOUD @ VALVE COVER, red hot header, spews coolant from weep??

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Picked up a 06 crf450r last night to replace one i sold not long ago (had regret)...

It spews water under acceleration out the weep hole, doesn't seem to be circulating ( I added a small amount of coolant to radiator and everything that spewed was clear like the water and not mixed.

header is red hot at motor within 2 minutes

it idles high then surges and does this a little bit

It definitely is louder at valve cover than my last----------I took a screw driver to listen for the noise on case and its definitely the valve cover and sounds more like the cam chain... Valves were recently done and checked per the guy before him and new guy didn't ride it more than 2 times crashed and got nervous...

 

It backfires lol....

 

It wasn't a screaming deal but it was a fair price, I would rather see about fixing it and not having to be a hassle to the seller because of inconvenience or ignorance...

 

The motor has been rebuilt not long ago, has 12:1 wiseco piston, ferrea intake valves, stock exhaust, pro circuit ti exhaust and header, stock crank and cylinder...

apparently it ran fine but who knows... the motor has allot of pull and aside of slap or really noisy valve cover sound and does not miss a beat when throttling hard... it doesn't stall when letting off throttle...

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It sounds like the chain is slapping in valve cover area, Ill check valve clearances but the idle part gets me and if its running lean....as does the circulation problem with the water pump.... I will drill the small hole in the impeller to help with the cavitation...

 

WATERPUMP ?????????? Is there supposed to be a copper washer between the impellor and the shaft... When I took the impellor off there was a small copper washer like a spacer or buffer between shaft and impellor material???????

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If mine, I'd check the cam chain tensioner to see if it's bad and see if there is any up and down play in impeller (could be balancer bearings).

The surging is from a lean condition, check the intake and airbox boot connections and spray some carb cleaner on gasket areas, etc, and see if idle goes up. You may need to rebuild carb.

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I agree with the above statement that it could be the cam chain tensioner.  Honda tensioners seem a bit weak and can break in my experience.

I think you need to cure your lean condition before assessing the cooling issue.

 

The lean condition could be the following:

Carb boot leak, cracked, very common

Stuck float bowl

Plugged pilot

Exhaust leak near mid pipe or header

As mentioned above use starter fluid or carb cleaner and spray around all incoming and outgoing air

 

 

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It has the pro circut  ti4 exhaust and full header....i made sure the water pump has hole in impelli, got ice for it and going to spray carb cleaner and see if she idles up anywhere as suggested...

 

If they get red hot then I'm ok with that..understandable...

 

The water is flowing I fired bike up with radiator cap off and  it's moving for sure.

So I will do as you guys suggest I'd rather diagnose and fix and ride than drop this back on the guy ifnirs relatively simple...

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1 hour ago, Bullcrew said:

It has the pro circut  ti4 exhaust and full header....i made sure the water pump has hole in impelli, got ice for it and going to spray carb cleaner and see if she idles up anywhere as suggested...

 

If they get red hot then I'm ok with that..understandable...

 

The water is flowing I fired bike up with radiator cap off and  it's moving for sure.

So I will do as you guys suggest I'd rather diagnose and fix and ride than drop this back on the guy ifnirs relatively simple...

Dont just spray carb cleaner in the carb. It will expand the rubber diaphragm and you may have to go in an replace it. The only place you can spray carb cleaner is the float bowl and pilot jet unless you disassemble everything first and remove all rubber orings etc. dont ask how i know this. ;). And yes if you sit and idle your bike will get hot. Your header should never be red hot though. Thats always a sign of being too lean. Same for backfiring on deceleration. 

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http://www.dirtrider.com/features/protips/141_0707_keihin_fcr_carb_rebuild

Good article on rebuilding the FCR.

https://www.rockymountainatvmc.com/rm-rider-exchange/videos/how-to/dirt-bike/

Good video on the same.

If the links don't work, Google Ty Davis FCR rebuild. It's a Dirt Rider article. 

 For the other go on Rocky Mtn ATV/MC and scroll done to the bottom. Click Videos/how-to/dirt bike/intake and exhaust and look for a video named How to properly clean a carburetor.

Edited by HRC27

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Ok rebuilt the waterpump...seals, bearing, shaft and assembled..now the gasket is leaking a little oil lol...no biggie I'll check it out BUT it is still spewing out weep hole when throttling up

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59 minutes ago, Bullcrew said:

Ok rebuilt the waterpump...itals, bearing, shaft and assembled..now the gasket is leaking a little oil lol...no biggie I'll check it out BUT it is still spewing out weep hole when throttling up

Did you reuse the right cover's gasket?  Did you check the balancer for play? If those are bad It will cause the seals to fail. I'm assuming you Installed the seals correctly.

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OK everything as far as the water pump was done correct the leak is because the balancer has bad bearings a fair amount of movement...

 

Also I think I figured out why it vibrates so hard... The balancer detent wasn't lined up with the cam detent so I moved it back to line it up... Ill grab the 2 bearings, oil seal and both gaskets tomorrow...Trying to get it done to take my son riding Sunday... Just got him a new tire on his ktm 50sr and did some work on it so its ready to rip... Its all waiting on me now lol....

 

 

And thank you HRC27 I actually hadn't looked at balancer till you suggested it so I went back in and sure enough... THANKS...

Edited by Bullcrew
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