Cylinder pressure and power valve question

phnx85

New member
Joined
Oct 3, 2009
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14
Age
39
Location
Norway
I'm serviceing my engine in my SRX 700 for the first time. I did a pressure test, engine was room temperature, and i got around 65 PSI on all cylinders. I know that not all testers are the same and could give different values, but shouldn't i be getting 120-140 PSI? The tester is brand new, never been used. I pulled 4-5 times and WOT. Tried both with and without spark plugs in the two other cylinders, gave the same reading.

I also disassembled the power valves, however i could not remove them from the cable. What's the trick? Didn't want to pull to much on the cable. The middle valve had a snapped cable, valve seemd fine no pull trough, so i guess i just have to replace the cable.
 

they start to wear in the valve over time (actually starting to pull through) but you have to push them out and keep working at them they will come out
 
oh sorry did you have the same reading all three cylinders? if you did and the sled runs crisp i would bet the gauge is off ive seen the read off like that, i had one gauge at a dragboat race tell me my just rebuilt 260 had 78psi-85 psi i will never forget that
 
So just work on the valve and they will pop out of the housing and expose the cable? So no need to slacken the adjuster on PV servo?

Yeah, i get the same reading on all cylinders (+- 5 PSI). Should i see higher reading if the engine was warm?
 
you didnt pull the engine over enough times, takes about at least 10 pulls per cylinder.

just pull a little bit on the valve the servo motr will move and let you remove the valve from the cable. When you go to reassemble, just take a pecie of rag and a pair of pliers,put rag on servo pulley and twist with pliers-GENTLY and it will wind up the slack and pull the valaves into the housings.
(rag keeps you from marring up the aluminum pulley)
 
The valves cleaned up nicely ;)!

Had a look at the pistons trough the PV opening and there were no signs of blow-by. Should i remove the domes and inspect the pistons? I have a Wiseco piston kit, but it seems like there's no reasons to change the pistons even tough it has around 10000km on the speedo.

Is it safe to run the engine with one snapped PV cable until i get a replacement? I guess it should be fine, since i dont know when the cable snapped. Not going to hit the trails, just need to move the sled.
 
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I'm cleaning out the carbs aswell, following the Carb cleaning 101 guide. It didn't say anything about cleaning the chock. Is it supposted to be cleaned? I'm also having trouble removing the float, the pin that is holding it won't budge and i'm afraid of using to much force.
 


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