Ready to go back to stock EX Cam!!! Help please.


95 replies to this topic
  • jbrooks26

Posted December 14, 2005 - 01:48 PM

#41

OK, I tried the oil down the spark plug hole trick to no avail so as soon as I get time, OFF WITH IT'S HEAD!!!!! I will keep everyone updated. Thanks for the help.

Josh

  • Indy_WR450

Posted December 14, 2005 - 05:37 PM

#42

I want to know if that Hot Cam bent your exhaust valves :applause:

  • StreetbikePimp

Posted December 15, 2005 - 10:22 AM

#43

I don't know the "oil down the spark plug hole" trick. Did you do a leak-down test?

  • jbrooks26

Posted December 15, 2005 - 03:16 PM

#44

I put about a tablespoon of oil down the spark plug hole in case it had been washed down enough with gasoline to lose compression around the rings. I have heard of this on several occasions, just wanted to make sure I wasn't missing something simple like that. I have not done a leak down test, I don't have that equipment and have not had a chance to make my own. I figured I could pull the head and find out the same thing, I am already half way there just by having the cams out. I figure that if I have a bent valve then i will be able to see evidence of it hitting the top of the piston.

  • jbrooks26

Posted December 16, 2005 - 05:36 AM

#45

I want to know if that Hot Cam bent your exhaust valves :applause:


Indy,

I don't believe it did, I really think that I had it out of time the first time I ran it by 1 or 2 teeth. I will let you know what I find out when I get a chance to pull the head.

Josh

  • Flooder305

Posted December 16, 2005 - 08:33 AM

#46

Less talk more pull, and take pictures..... :applause: :bonk: :cry:

  • rtrolli69

Posted December 20, 2005 - 07:25 PM

#47

Hey Josh,hang in there bud.It sucks that things can get so complicated!?!?!This thing has gotten interesting to say the least.Slow dwn take a breath,I admire you for admitting your mistakes and working thru them.Indy and others can help thank goodness we have a place to take our troubles too.Ive been thinking of a internal mod of sort,my 05 450 runs strong,I should just probably train a little more and ride harder.Best of luck..Russ

  • jbrooks26

Posted December 22, 2005 - 03:36 PM

#48

Ok, here is a small update for you all. I built a little hose, similar to a leak down tester without the gages, to pressurize the cylinder and check for leaks. I was unable to keep the engine from turning over from TDC with the air pressure(using 20 psi) so I pullled the EX cam and held the chain out of the way of the intake cam to let the air push the piston all the way down without engaging the valves. turned the lobes of the intake cam straight up in the air and left the ex valve out. I still have the cam cover off, and the only place I hear any air coming out is from the crank case. Does this tell me anything? It is not a large ammount of air, and I would expect to hear some leaking through the ring gaps. Any thoughts on this latest development? Increased to 50 psi with similar results. I could press my ear against the end of the exhaust pipe and I was not sure if I was hearing air or if I was just hearing a transfer of the sound from the engine through the exhaust. The more I do here the more confused I get. Why can't anything work right the first time???? :applause:

  • CRFThumper

Posted December 22, 2005 - 05:08 PM

#49

I would think that if you bent a valve bad enough to lose squeeze you would be able to hear air out of the pipe or intake! Did you ever take the cams out and try to kick it over?Just be sure to hold the chain so it doesn't get bunched up!There has to be a answer for all of this!

  • jbrooks26

Posted December 22, 2005 - 06:17 PM

#50

I would think that if you bent a valve bad enough to lose squeeze you would be able to hear air out of the pipe or intake! Did you ever take the cams out and try to kick it over?Just be sure to hold the chain so it doesn't get bunched up!There has to be a answer for all of this!


OK, I just went back out and tried this again for certainty sake. I pulled the EX cam, held the chain up off of the intake cam and kicked it through the compression stroke. It does not fly through the stroke mind you, I have to kind of stand on it, I weigh about 190lbs. I should also note that I am standing on the bike, holding the chain out of the way of the intake cam, and kicking the bike through all by myself. I don't have any helpers right now. I don't remember being able to kick through the comp stroke before so I am certain that something is still amiss here. Thanks, Any other thoughts on my air pressure test?

josh

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  • jbrooks26

Posted December 22, 2005 - 08:05 PM

#51

Borrowed a compression tester from a friend of mine, I will post the results tomarrow.

  • chiefsfan.58

Posted December 22, 2005 - 09:43 PM

#52

jbrooks, you did the compressed air test with the ex. cam out and could hear air seemingly from the crankcase........ does anyone think that if he were to do the same test but this time add that teaspoon of oil into the spark plug hole and repeat to see if the sound decreases. If it does not decrease, then the compression loss is more likely from the top end and not the rings? I know this concept works when cranking an automotive engine but I'm unsure if it also has the same affect using compressed air. The concept being that the oil helps to seal the rings to the wall of the cylinder.
If I am way off, please someone tell me as I could use the info to expand my understanding.
best of luck to ya jbroo....

  • jbrooks26

Posted December 22, 2005 - 10:51 PM

#53

jbrooks, you did the compressed air test with the ex. cam out and could hear air seemingly from the crankcase........ does anyone think that if he were to do the same test but this time add that teaspoon of oil into the spark plug hole and repeat to see if the sound decreases. If it does not decrease, then the compression loss is more likely from the top end and not the rings? I know this concept works when cranking an automotive engine but I'm unsure if it also has the same affect using compressed air. The concept being that the oil helps to seal the rings to the wall of the cylinder.
If I am way off, please someone tell me as I could use the info to expand my understanding.
best of luck to ya jbroo....


I have already tried the oil trick. in fact it was just a few days ago and I may have put too much oil in there, Haha. When I first pulled the spark plug it was oil soaked. But that will be another problem that I can fix when I get the compression straightened out. Thanks for the suggestion though, keepum coming.

By the way, are you in Kansas? I ask because of your screen name.

Thanks again,

Josh

  • CRFThumper

Posted December 23, 2005 - 04:46 AM

#54

OK, I just went back out and tried this again for certainty sake. I pulled the EX cam, held the chain up off of the intake cam and kicked it through the compression stroke. It does not fly through the stroke mind you, I have to kind of stand on it, I weigh about 190lbs. I should also note that I am standing on the bike, holding the chain out of the way of the intake cam, and kicking the bike through all by myself. I don't have any helpers right now. I don't remember being able to kick through the comp stroke before so I am certain that something is still amiss here. Thanks, Any other thoughts on my air pressure test?

josh



OK,but is it harder than with the cams in?That should be enough squeeze to start it.

  • jbrooks26

Posted December 23, 2005 - 08:20 AM

#55

OK guys,

Compression tester shows somewhere between 60 and 90 PSI when kicked through. This tester does not have a high reading indicator so I have to try to watch it while I am kicking to see what it reads. I don't believe it is going above 90psi. I expected it to be higher, does this sound right to you guys?

Josh

  • jbrooks26

Posted December 23, 2005 - 11:26 AM

#56

From Bad To WORSE!!!!!!

I decided to pull the head and it is going downhill fast. First off, I can't seem to get the head free from the timing chain guides. Do I need to remove the guides? And to make matters worse, something just fell off of the head into the engine and I don't know what it was or where it came from. Any Ideas???? I am ready to light a match here!!

Never Mind, I discovered what it was that fell. It was the return spring for the decomp shaft. I still don't know where it went for sure however at least I know what I am looking for. I also got the head off, I didn't realize that the one chain guide would just pull out. The good news is that I don't see any evidence of a bent valve. No disturbance on the carbon on either the piston or any of the valves. The bad news, I am even more confused now than before and my bike is in pieces. Anyone, anyone??

Josh

  • Indy_WR450

Posted December 23, 2005 - 11:53 AM

#57

Sorry Josh, If no valves are bent I am at a loss as to why the bike had no compression when you went back to the stock cam and tried to kick it over? Did the stock decomp cable/ mechanism somehow stay open or have caused the loss of compression? :applause:

  • jbrooks26

Posted December 23, 2005 - 12:47 PM

#58

I had that same thought Indy, so I removed it. No change. I also just finished a fluid test using mineral spirits, and all of the valves hold up. Starting to doubt myself as to whether or not I could kick this thing over before without the decomp lever. I am learning a lot about how things go together though, I guess that is a plus. I am sitting here right now thinking to myself. "Self, did you let a fouled spark plug cause you all this trouble to start with? Are you really that stupid?" I guess I will have to answer that question next week sometime. It is time to get ready for our Christmas trip to the folks' house. Merry Christmas Everyone!!

Josh

  • jbrooks26

Posted December 27, 2005 - 03:36 AM

#59

Does anyone have any suggestions as to what to look at before I put this back together? I used Mineral spirits to check the valves, no leaks after 5 minutes. Cylinder walls look and feel smooth. Head Gasket is intact and looks good. Piston does not show any signs of wear that I can see. Is there anything else I should look at before I go on? Thanks,

Josh

  • CRFThumper

Posted December 27, 2005 - 03:52 AM

#60

Wanna use my 357.?It HAS to be in the shims,timing,decomp or as you said it's been low all along!Hang in there! :applause:




 
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