Cylinder numbering?
05-09-09, 06:44 PM
#32
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Ok, update here! I havent gotten to pressurizing the cylinder with a compressor because I do not currently have the equipment to do it, the compression tester I have will not detach and hook up to the compressor hose because I have a cheap one.
I started working on checking the valves, but I have never actually done anything like that before so it took me a while to figure it all out. After thoroughly searching the internet I found that I need to find Top Dead Center on the cylinder and then check the valves clearance, but here is where I get confused.
Do I find TDC on cylinder 4 to check it, or do you use TDC from cylinder 1 to check all the valves?
I did check the gaps for the valves on #4 after I found TDC for that specific cylinder, but my readings are strange, one problem I am having is that I do not fully understand how that sheet you gave me works, am I only using the two numbers at the top of the sheet for intake and exhaust? I believe they are 0.15 for intake and 0.25 for exhaust, which valves are for intake and which are for exhaust?
Cylinder #4 is definitely the problem, it is hardly producing ANY pressure at all when I crank the engine through the pulley and I can hear a slight let-out of air quite well when it is on the compression stroke but I can't quite pin-point it.
I started working on checking the valves, but I have never actually done anything like that before so it took me a while to figure it all out. After thoroughly searching the internet I found that I need to find Top Dead Center on the cylinder and then check the valves clearance, but here is where I get confused.
Do I find TDC on cylinder 4 to check it, or do you use TDC from cylinder 1 to check all the valves?
I did check the gaps for the valves on #4 after I found TDC for that specific cylinder, but my readings are strange, one problem I am having is that I do not fully understand how that sheet you gave me works, am I only using the two numbers at the top of the sheet for intake and exhaust? I believe they are 0.15 for intake and 0.25 for exhaust, which valves are for intake and which are for exhaust?
Cylinder #4 is definitely the problem, it is hardly producing ANY pressure at all when I crank the engine through the pulley and I can hear a slight let-out of air quite well when it is on the compression stroke but I can't quite pin-point it.
Last edited by Cling; 05-10-09 at 01:48 PM.
05-09-09, 07:28 PM
#33
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might as well do it the quick easy way, just turn the engine over till either the intake, or exhaust lobe ( is pointing up), and then check the clearance at those valves. Then turn the engine over further, till the other set of lobes are pointing up.
If you have a good gap, or at least some gap then you will want to start pulling the head.
Are the gap readings you have in mm?
If you don't have the equipment to pressurize the cyl, I wouldn't sweat it too much. Chances are (since oil in the cylinder did not improve the compression). That you have a blown head gasket. Once you pull the head, look at the gasket closely, you will probably be able to see the blowout. If there is nothing obvious, turn the head upside down, and fill the cylinder head with rubbing alcohol, if you have a burned valve you should see it drain out.
If you have a good gap, or at least some gap then you will want to start pulling the head.
Are the gap readings you have in mm?
If you don't have the equipment to pressurize the cyl, I wouldn't sweat it too much. Chances are (since oil in the cylinder did not improve the compression). That you have a blown head gasket. Once you pull the head, look at the gasket closely, you will probably be able to see the blowout. If there is nothing obvious, turn the head upside down, and fill the cylinder head with rubbing alcohol, if you have a burned valve you should see it drain out.
05-10-09, 02:28 PM
#34
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Ok George, I figured out how to check the valves finely. Here are my findings. Looks like I have a few bad readings, but the worst of course is on cylinder number 4. The bottom right valve is extremely tight! I put down .0015'', but it was actually less then that because .0015 would not fit under that and my feel gauge doesnt go any lower.
05-10-09, 03:50 PM
#35
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Try pulling the shim out and see if you get your compression back. You can run with too much clearance (actually better than too little clearance - that's what causes burned valves and carbon buildup on the seat) - you just might not get all the power out of that cylinder, but it won't hurt it.
05-10-09, 04:38 PM
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Do you have a manual on this car? Like a hayes. Or you could go on line to alldata and purchase a sub for your car.
Mind you I am at work now, and do not have access to my manual. But I believe that these cars have hydralic lifters. I would suggest looking up the procedure for replacing the lifters. What we want to do now is pull the lifters (the two exhaust for #4). Measure the valve stem height, and then take a close look at the lifter.
It is odd that you have too little clearance. It would seem that the only way that could happen is if the valve seat was receding into the head, or the lifter has a problem.
On a good note, it looks like you may not need to take the head off. It is a good possibility that when you figure out why you have no clearance, and correct the problem. Your compression will go back up. I'll keep my fingers crossed for ya
Mind you I am at work now, and do not have access to my manual. But I believe that these cars have hydralic lifters. I would suggest looking up the procedure for replacing the lifters. What we want to do now is pull the lifters (the two exhaust for #4). Measure the valve stem height, and then take a close look at the lifter.
It is odd that you have too little clearance. It would seem that the only way that could happen is if the valve seat was receding into the head, or the lifter has a problem.
On a good note, it looks like you may not need to take the head off. It is a good possibility that when you figure out why you have no clearance, and correct the problem. Your compression will go back up. I'll keep my fingers crossed for ya
05-10-09, 05:17 PM
#38
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Thanks guys, I bought another car today so that I could keep this thing taken apart long enough to fix it, I will start again tomorrow and completely disassemble the valves for #4 and get back to you on the matter.
05-10-09, 08:08 PM
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I was aware of the adj discs, but I thought the lifter itself was hydraulic. I wish I had my manuals here to look that up, I know I could very well be wrong.
If it is a mechanical lifter, I would suggest following the valve adj procedure and finding out exactly how much difference on disc size that you require in order to get it into spec, and then check compression. If it is not too much of a change, and compression comes back. I would run it as is, and then re-check the gap at the next oil change.
If it is a mechanical lifter, I would suggest following the valve adj procedure and finding out exactly how much difference on disc size that you require in order to get it into spec, and then check compression. If it is not too much of a change, and compression comes back. I would run it as is, and then re-check the gap at the next oil change.
05-11-09, 07:11 AM
#41
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Which is strange - I ALSO thought most cars had hydraulic lifter now adays! But mechanical are more reliable, and have zero slop, so are probably better for the high output engines they are putting out now.
05-12-09, 06:26 PM
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Ok guys, good news, thanks matheny for the idea, I took apart the cams and just ended up pulling that whole valve cap out, and then I reassembled and ran another compression check on #4 and BINGO!!! 210PSI! .... so, now I am at a loss, whats the next step, I suppose I need to have 0.007'' shaved off the top of that shim or what? There is no other way to actually adjust the height other then changing the size of the shim thats in the cap right?
05-12-09, 07:59 PM
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I would not recommend shaving the shims. And I am a little confused, where did you get a number of .007? If you look in the manual, there is a special tool that is used to compress the valve enough so that you can slide the shims in/out without removing the cam. It would be a good idea to try to either rent one, or purchase (they are not too expensive). Then you will need to try to figure out what thickness of shim that you require. As a good guess, I would suggest measuring the shim that you removed, subtract the optimal valve clearance ( I am guessing that this is .007, and then subtracting .002 more). My reasoning behind this is that valve was obviously not closing at all.