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Old 04-02-2013, 12:11 AM   #1
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Join Date: Jul 2011
Member Number: 3656
Location: NH
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Default Lifter issue

I have a 75, 304 that sat for a while and I didnt know about the break in for sitting motors. I did use marvel and hand crank the engine about 500 revolutions slowly before cranking.
The motor runs and seemed to be fine but had a tick and a slight "offness" about it. Pull the valve cover and there was #6 intake pr bent. I then proceeded to check all the valve stems to make sure they were freely moving on their own weight, #6 was sticky but I got it clean using the technques in the sticky so the upper end seems ok.
That being said the #6 lifter plunger has no give, it seems stuck. Is this normal. I havent pulled the others yet to check them. However I did turn the motor while watching the lifters and they all raise and lower.
The truck has 20k miles original, yes twenty thousand miles and the lifter looks new, slight convex no cupping or even wear marks visable, I watched the lobe thru the lifter port and it to is well oiled and looks good. Hell the valve train looks new.
Question is, can I fix the lifter? Thats if the plunger is stuck and not loaded, I am concerned that the lifter bars that are for manually lifting the lifter out of the port are gone...looks like the pushrod damaged them.
If no, can I replace all of the lifters with new, or must I replace the cam if I replace the lifters?
1975 Scout II
304, T19.
Mostly original with Holley 2300 and Pertonix III as only real mods.
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Old 04-02-2013, 05:39 AM   #2
Robert Kenney
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Location: So Cal
Posts: 3,421
Default Re: Lifter issue

You probably have badly varnished fuel and fuel system parts. I have seen this many times and the intake valves are the ones effected by the varnish being deposited on the stems. It ultimately gums up the intake valves and they stick. The odd geometry in the sv valve train coupled with the long pushrod ends in the pushrod failing...
You need to get all of the old fuel out of the system including the varnish that has deposited on the walls of the fuel system... I'm going through this right now on my Scout. It sat to long with the crappy kalifornia gas in it. Now when I start is the valves are hanging up and it has about 0 compression on a couple of 3 cylinders. My solution was to drain the fuel add new chevron premium with techron to the tank fill the carburetor with aerosol carb cleaner (acetone works too). I also spray more into the carb itself. It then fires up with no issues... I have a heavy wall manton push rod set in my engine so I don't get bent ones anymore. It took a couple of runs before the symptoms went away... By the way the engine is all new so cam bearings or non oiling rockers are not the problem.

Your lifters are fine the lifter is full of oil so it seems stuck or solid. You don't want to mess up the matted cam and lifter set my mixing them up or installing new lifters... That can destroy a cam.... Replace the bent rod and do the carb cleaner bit I described above. You already have the valves unstuck so that will be ok... Make sure you drain the old fuel. When you do get her running again you need to drive it for a spell before shutting it down so the crap is worked out and the valve train is oiled well..
Robert Kenney

“Don't lift until the fear of death over comes the fear of speed.” Author Unknown
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