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Old 04-22-2011 | 09:09 AM
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hammers and duct tape, what cant they fix?
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Old 04-22-2011 | 01:43 PM
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DO NOT RUN THE MOTOR! Pull the valve cover and check the operation of each valve, hopefully one of the rockers will be real loose. If not, check the keepers carefully, I dropped a valve once and the spring and retainer held the rocker tight. If rockers are tight and valves are still in their keepers then you probably have a hole in the piston. If one of the valves is hanging, it could be rust, or it could be bent, pull the appropriate manifold and inspect it. Either way I would pull the head and fix the problem. Even if it's only rust, if it's bad enough to hang the valve through a compression check of the motor, it's bad enough to score the valve guide. I'm only telling you all of this because I have a similar situation. I bought a 1998 Velocity with 50 hours on it a couple years back. I ran a leak test last month after running it two seasons and 2 cylinders were over 50%. When I pulled the heads, the 2 bad cylinders had a rust print on the cylinder walls. The rust was heavy enough to destroy the rings, now I'm looking at a rebuild. It would have been a lot cheaper had I checked it sooner. I hope you have better luck then me.
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Old 04-22-2011 | 02:05 PM
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If a valve is hanging and you would like to find out before you pull a valve cover, hook up a air hose to the spark plug hole and put some compression to her and listen for air out the exhaust or intake. Simple trouble shooting to give you a idea whats going on. if you hear air out the oil breathers bummer!
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Old 04-22-2011 | 04:26 PM
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i put air in the cylinder and found the intake valve was open and blowing out carb. Got valve cover off and the rocker was tight so i backed it off and filled it with air again and no more blowing threw carb. So im gonna adjust valves ( maybe ill get it right this time) and check comp again. Looks like i had no comp in #7 since july of last year.
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Old 04-22-2011 | 05:12 PM
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If that is the case that engine would have been backfiring pretty badly.
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Old 04-22-2011 | 06:06 PM
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I thought the same thing boat1. Towards the end of season i had to let it warm up a little before backing of trailer or it would die. Maybe valve sealed when warm? I adjusted valve and rechecked comp, getting 164 now. Pushrod didnt look bent and valve tip and spring look in good shape. Should i check anything else? is it ok to run and see how it does?
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Old 04-23-2011 | 09:18 AM
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For clarification, you now have compression on all eight cylinders, fresh spark plugs, and the valves adjusted correctly? When you did the compression test was the carburetor at WOT or idle, was the battery fresh, were all the spark plugs in except the cylinder being tested? I asked because it will tell me alot more about how far off the seat the valve was. If you have all the things done in the first sentence, along with fresh oil/filter, I would run the engine and get it up to temperature and see how it sounds. Check the timing also.
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Old 04-23-2011 | 10:57 AM
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Originally Posted by RunninHotRacing163.1
u meant rubber mallet right ????
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Old 04-23-2011 | 11:50 AM
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yes i now have comp on all eight cylinders, new plugs (i just had the cylinder i was checking out), Battery was just charged and carb was at idle,
Havent changed oil and filter yet, That was next and also have new cap and rotor ordered im waiting on.
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Old 04-23-2011 | 09:47 PM
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Change the oil put on the cap an run it. The valve did not have to be off the seat much at all with the carb at idle. You should have the carb WOT while cranking a compression test. I also remove all the spark plugs but that is not totally necessary.
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