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engine problems...part3
As the engine noise sounds like it's coming from the lifter valley (see previous thread for fuller description) could I have a damaged lifter? what damage could it sustain?
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Do hydraulic lifters collapse? I'm not for sure....maybe someone else could answer that. I guess if it has, you could check to see if you're getting the lift that you should be with a dial indicator. Does this make sense guys?
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Hey, do you have an MSD coil on the engine?
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Didn't see the previous post (maybe I did,don't know), but in answer to whether Hydraulic lifters collapse the answer is YES. They make a hell of a racket as well when they do,like a loose mechanical lifter. It is virtually impossible to get them to pump up in a running engine as well. If it is a collapsed lifter,trace which one and replace it, once it's collapsed it will probably do it again. You should be able to tell which one by pulling the valve covers and turning the engine over so you can check each cylinder, the one that is loose is your culprit. It could be more than one.
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I have watched your thread and thought about some of the demons I have chased over time and here is a pretty good way to eliminate your valve train.
Get some old towels, unbolt both valve covers, lay towels around your heads and not on your headers so as to catch any oil that may splash off your rocker arms. Start your engine and walk around and remove each valve cover and observe each lifter and listen for any noise. After you pull the valve covers off one side and check it out set the valve cover back on ad do the other side. If you still cannot pin point the noise. Drain your oil and pull your oil pan and take a look at your bearings the noise could be a loose main or rod bearing. I had a spun main bearing last spring that sounded like a bad lifter. Good luck. Clois Harlan |
Thanks guys,
MSD coil and ign, yes Had the covers off (this started when a roller rocker came loose and the engine started "coughing" back through the carb) but all the valvetrain's been adjusted and seems nice and quiet took off the rockers for no5 cyl and removed the plug to see If I could isolate the noise, but the noise of the air coming out through the plug hole drowned out everything else, guess I('ll have to take off the inlet and have a look see. Simon |
Simon...this may be a shot in the dark...but I have heard MSD coils make quite a bit of noise.......and usually they're mounted pretty close to that area.
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Thanks, but it's not close enough (I did have a listen though)
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Hi,
Do you run a mechanical fuel pump? if so then the cam eccentric or bolt could be loose under the timing cover. There is also a cam 'walk' plate there at the front of the cam with 2 bolts holding it on. The only other thing attatched to the cam is the distributor, do you have the proper cam gear on it for a hydraulic cam, it's different than the roller cam gear. Good Luck, Perry.:cool: |
OK,
I've taken the intake manifold off and unfortunatly, there's absolutly nothing wrong with any of the lifters. Also from what I can see, there's nothing wrong with the camshaft either. The cam is an edelbrock performer plus with an MSD electronic distributor, the gear on both seems fine. Also I have an electric fuel pump I guess this means it's something deeper in the engine. I suppose a complete teardown is the only way to go now. DAMN:CRY: |
Is it possible that this is something to do with end float on the cam? I've not got down that far yet so can't tell.
I'm guessing that whatever it is has got to gave something to do with the rocker arm coming off, as the engine was lovely and quiet before that happened. Could it be a broken piston skirt? could that have been caused by my problem. Thanks guys. Simon |
Simon,
You may want to send out a plea to Wilf Leak, his bio says he is in Leicester, UK. Wilf has offered up some very good advise to me from time to time. Good luck Simon and keep is posted as to what you find. Clois |
I know this sounds implausible, but bear with me. I witnessed it myself.
I was chasing a clicking sound that I attributed to lifter/valvetrain noise. Nothing was amiss anywhere that I looked. The stethoscope was nonspecific in telling me the source of the noise. I took the fan belt off and ran the engine. No help. I removed the fuel pump and blocked off the opening, then ran the engine. No help. Finally, I noticed that the big oval air cleaner base was rubbing on a spark plug wire to the point that the spark was arcing to ground there. The snapping noise was amplified through the aluminum base and it sounded like a metallic tapping. An easy fix after a tough search process. You might look for something similar. |
Good Grief Simon, you are going through it, aren't you! My sympathy, FWIW.
With a non-operative exhaust valve, you will have generated some "interesting" pressures within the affected cylinder. Head gasket would be suspect, also your noise may just be something as simple as an exhaust gasket blow. I would also be concerned about the health of the affected rocker, lifter, and pushrod - they would have taken quite a beating. You would be very unfortunate, IMHO, if you had cracked a piston skirt, or otherwise damaged the piston in that cylinder, but it could happen. Only one way to be 100% certain - pull the affected piston and inspect it and it's conrod bearings. Did you do a compression check on the affected cylinder? Or a leak down check? Data from these could be illuminating. Just think how much advice you will be able to give others once that thing is sorted! (sorry, just trying to look on the bright side). If it makes you feel any better, I shall be swapping out the diff on my car sometime soon, and that is not a job I look forward to. Luck Wilf |
w
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simon ,
As long as we are taking potshots.......a blown exhaust manifold gasket makes a loud metalic click that can sound exactly like valve train noise.....I loose one on my passenger side once a year due to engine torque....always sounds like a stuck lifter. KK |
Finally, I think I've got it sussed.
It seems to have been a collapsed lifter causing my problems. I didn't quite understand how they worked until someone explained it and I realised that the intake had been trying to open the valve on very high pressures and this had obviously damaged the non return valve (in my stupidity I thought because I couldn't compress the lifter easily, it was ok) I stripped the intake off again and removed both lifter for no5 cylinder. Sure enough after cleaning them of oil I was able to blow backwards through the intake lifter. I'll get a new set tomorrow. Thanks for all your help, please pardon my ignorance. Simon Have a happy Xmas.:p |
Simon - you have NO idea how tightly my fingers are crossed for you. It's about time you ended up with a serviceable engine.
Luck. Wilf |
OK, put in two new replacement lifters in the affected cylinders, re assembled the engine....still knocking.
I give up Theres going to be a big fiberglass and sbf bonfire round at my house tonight and you're all invited:CRY: |
Wilf,
How far are you from Simon? He sounds as if he is really getting frustrated and you know how these things can do that. Then someone else comes along that hasn't listened to it and gotten stuck on a certain train of thought and they quickly point out something obvious that you are overlooking. I have had this happen to me several times and then I felt like a fool for not noticing what the real problem was. Ron :) Simon, Don't give up yet. That comes when you replace the engine with a brand new one and still have the knock.:LOL: :3DSMILE: |
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