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Topic Review (Newest First)
11-23-2010 01:19 PM
bowtie76 I will do that here in a few KC. I was checking the timing when A buddy here at work said there was a puddle under the car. I turned the car off and looked and Now I am leaking tranny fluid from the cooler line. i just replaced it a few weeks ago. Some how it has a pin hole in it So I will be tackling that tomorrow. But I will def do what you are saying and check the valve lash on all the cylinders not just the one. Thanks for the help. I am hoping that all these issues will go away soon. Well at least for a short period of time. LOL I need a mental break as well as my pocket book
11-23-2010 01:00 PM
kc8oye that could well be your miss right there.

you need to set that rocker correctly.

get that cylinder to TDC _COMPRESSION_ stroke. (put your thumb over the sparkplug hole, you'll feel the compression stroke start)

then if you can't see into the spark plug hole, I find a screwdriver works well to put in the hole, and turn the engine BY HAND.. dont' bump it with the starter if you have something inside the cylinder! once the piston is at the top..

loosen the rocker nut until you can move the pushrod up and down between the lifter and the rocker.
then slowly tighten the nut back down until you can only just barely move the rod up and down. now twirl the rod back and forth between your fingers while you continue to tighten the nut. as soon as you feel any resistance at all, stop. now add 1/2 turn to the rocker and you are done.
11-23-2010 10:58 AM
bowtie76 No I didnt check the valve lash. i jsut tightened it down enough so it felt the same as the others. But I am going to check the valve lash and make sure they are all good. A mist of all this jsut saw a tranny leak under the car. GOOD TIMES LOL
11-22-2010 09:48 AM
kc8oye
Quote:
Originally Posted by bowtie76
. As far as I know they had never been touched other than the one that I found loose and I just tightened it down so I wouldn't damage it or the push-rod.
uhhhh... how exactly did you 'just tighten it down' ?
did you follow the correct procedure for setting valve lash? or did you just crank it down as far as it would go?
11-22-2010 09:47 AM
kc8oye
Quote:
Originally Posted by 454C10
or 3

A rocker arm stud could be pulling out. If he doesn't have screw in studs.
ahhh yep.. good catch. I fergot about that one!
11-22-2010 07:38 AM
454C10
Quote:
Originally Posted by kc8oye
two things can cause a rocker to become loose.

a) wear.
b) the nut backed off.

a is much more common, usually the cam lobe going away.. but occasionally those lock nuts can back themselves off and you just need to replace the nut and re-lash it.

if the cam lobe is going away, the valve won't open as much. to accurately check the cam lobes, you need to set up a dial indicator and measure all of the rockers. if you know the cam specs, compare your measured numbers to that, if you don't, the numbers should all be within a close tolerance of each other (I think about 10% is normal) remember that intake and exhaust lift numbers can be different...

or 3

A rocker arm stud could be pulling out. If he doesn't have screw in studs.
11-22-2010 06:24 AM
bowtie76 I am sorry my posts are confusing. i have been just as confused as anything else overdrive. it seems like I am constantly coming across something new that seems like it might be an issue. But I have 4 days off this week. So I am going to rent the compression tester adn be doing that. I did get a chance to get underneath the car yesterday for a bit. found the motor mounts were bad. i bought some replacements. got them installed but the damn passenger-side bolt won't line up to save my life. So I will be elbow deep into it Thursday. So I will definitely do what you suggested. I will check the valves as well. As far as I know they had never been touched other than the one that I found loose and I just tightened it down so I wouldn't damage it or the push-rod. So I will check the lash on them. So again sorry it seemed very confusing. It just gets to a point that what you initially find as the problem and fix it. Just doesn't help out at all. I just think it is time to buy a built 383 from Engine factory adn call it a day LOL
11-19-2010 09:01 PM
kc8oye two things can cause a rocker to become loose.

a) wear.
b) the nut backed off.

a is much more common, usually the cam lobe going away.. but occasionally those lock nuts can back themselves off and you just need to replace the nut and re-lash it.

if the cam lobe is going away, the valve won't open as much. to accurately check the cam lobes, you need to set up a dial indicator and measure all of the rockers. if you know the cam specs, compare your measured numbers to that, if you don't, the numbers should all be within a close tolerance of each other (I think about 10% is normal) remember that intake and exhaust lift numbers can be different...
11-19-2010 06:29 PM
Overdriv I suggested you adjust the pre-load on the lifters because it sounded to me you either didn't do it right or might have messed up the adjustment by just tightening one or more down.

Now you are saying an intake valve is not closing?? That is a serious problem.

You are a bit confusing in your posts.

Step back, take a deep breath. Do the following if you want us to help you. Do not skip any step.

1. Adjust the lifter pre-load to 1/2 turn from zero-lash, COLD.
2. Warm up engine, that means till the engine is at normal operating temp.
3. Pull all spark plugs.
4. Prop the throttle wide open. Do not open wide for each one.
5. Pull the coil wire off the distributor and the coil.
5a. If HEI equiped, disconnect the large red or pink wire going to the HEI terminal.
6. Connect new compression tester to a cylinder to test. Start at #1.
7. Crank engine with starter till the gauge on tester quits increasing.
8. Write down reading on a piece of paper numbered 1-8.
9. Repeat steps 6-8 till you have tested all 8 cylinders.
10. Post your results so we can maybe help you further.

If you can't accomplish #1 then there is not much need to check compression.

When you are finished adjusting the lifters, look at the amount of threads sticking above the adjusting nut. If all nuts are the same, and no stud has pulled out of the head, and the cam lobes are OK, and there is nothing else broken or bent, there should be about the same number of threads above all adjusting nuts. If not, find out why not.
11-19-2010 02:32 PM
454C10 bad gas (old gas) can stick valves open. Especially on the intake valves.

Old gas gets sticky and stinky with age and gums up the valve guides and sticks the valves.

if the valves are sticking in one place, then that also tends to eat cams due to the extreme force on the lifter that is trying to move the stuck valve.

I have seen valve seats fall out which get trapped and hold the valve open.

but a cam lobe only can push, not pull (opposite of a rope).

compression test will show the dead cylinders. autozone rents tools for free (they give you the money back when you return the tool)
11-19-2010 02:29 PM
lmsport With intake off its easy to check the condition of the cam and lifters. Cam failure is so common in older cars when running modern oils that it is often the first thing that comes to mind with symptoms like yours.
11-19-2010 01:35 PM
bowtie76 Ok so here is a question i was pondering today at work. I know I had been told a possible bad lobe on my cam could cause the issue I have with my car. however, when I had the intake off and watching the valves open and close. They all did just that. the intake fully opened and just don't seem to close. So that would rule out a bad cam right? second It was mentioned to adjust the valve and make sure they are zero backlash. I read up on it. looks simple. But the question I have at this point. If i never had a issue up until recently, wouldn't the rocker be loose when the valve is closed? Not holding it open. A nut doesn't tighten itself down on a spring loaded valve. I am going to buy a compression gauge tomorrow morning and test the compression. but I wanted to get someones opinion on it before I start messing with the valves. There is one I know for a fact came loose and that was on the #4 cylinder intake valve. i just tightened it down to stop the slapping it was doing. So that I will adjust properly. but can someone answer the other questions I have please.
11-18-2010 05:50 AM
bowtie76 Thanks overdriv. i am going to try that this weekend. doesnt look tough at all. Most of everything I have learned so far has been hands on. So again thanks. I am hoping that helps some. Only because I dont want to start learning how to install a new cam yet haha. I was hoping to do that when I find another engine. i have always wanted to build one from the ground up to put in my camaro. It is looking like I might be doing that sooner than later.
but i do have anotehr question. I have read a few places about the popping also being linked to a lean condition or retarded timing. i know the timing isnt retarded. But as for running lean. Well that I am unsure of. I know it has plenty of fuel flow. Is there a way to find out if it is running too lean?
11-17-2010 09:47 PM
kc8oye hrrm.. I dont' see a delete post button.
11-17-2010 02:28 PM
Overdriv
Quote:
Originally Posted by bowtie76
Ok well at this point I wont lie. You just spoke spanish to me. LOL I uno dos tres and that is it. I got the basics and can take something apart and get it back together like it was new. IF I know what I am looking for and doing. As for what i have done to i. I have dealt with all that before. but i have never really messed with the rockers other than tightening the one up that was about to fall off.
Try this link from our knowledge base
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