small block chevy 350 hey guys have a issue with no.1 exhaust rocker arm putting out excessive oil .also has developed a knock after a load is put on it. shut motor off shake the rocker arm has the same sound as the knock when its running. broken valve spring? have a 15 second video but looks like it cant be posted . taken it to 3 shops no one can figure it out, man could use the help
I've had bad wrist pins dig into a cylinder wall before , when does it smoke ? Idle accelerate or decel. If you kill the cylinder does it quiet up? You may just have to tear it down to do some inspection. Valve guides or rings are about the only thing that'll make it smoke or something affecting those. Valve stem seals usually don't matter on the exhaust. Hell a lot of old school guys never ran seals on the exhaust side on drag cars. Sent from my iPhone using The H.A.M.B. mobile app
Well I'd venture to say they are clueless. If the rocker arm is loose there will be an obvious reason. Pulled a stud, broke a spring, bent pushrod, collapsed lifter. I sorta gather that the one pushrod is oiling excessively so I'd bet the lifter collapsed and pumping oil instead
Guide will also make a knock sound , Lifter bleeding off , Stud pulling out of head , rocker wear , Several ways to check , just a few , leak down test , ,run out indicator , Bore scope , Flat piece of gl*** ,
wow thanks no smoke cam lope looks like still functioning up and down. yes noise still there with plugs off. only in rev or drive with foot on the brake with some rpm does it rattle. neutral or park nothing. will dissemble this week and get back thank you
You can quickly check for a pulled stud with a straight edge across the tops of all studs. Obvious if there's a high stud. You can quickly chech for a bent valve with a measuring device and a compression test. It will be obvious that the valve stem or top of rocker will be lower and that cylinder will be down on compression. You can quickly check for a collapsed lifter by pushing down on the push rod. It should be solid, if it moves it will be obvious the lifter has an internal problem. The term "flat" cam is misleading. It's not that the lobe is gone but wearing and not as tall as it once was, it usually wears the base circle as well. When that flattening of the lobe happens it eats the lifter base as well- the lifter is now shorter and one obvious symptom of that is a rocker out of adjustment. You will still see valve action but the measured lift will be less. If you have the lifter out the end will be dished. Quicky check for a bent push rod by taking it out and roll it on a flat surface. It will be obvious if it's bent. At that point you can inspect the rocker arm and ball for abnormal wear-it should be obvious. If you don't know what it should look like compare it to another that's functioning. This should be less than 30 mins to determine where the problem is once the valve cover is off.
no high stud no bent valves 85-80 on comp test lifters solid no pushing down no play rocker arm and ball normal start it and few tenths of a mile just huge clatter what seem like out of valve train. Then goes away. clutters then hit p***ing gear all goes away. Great oil pressure. Runs like new. not a good photo but shows how much oil is coming fro the rocker compared next to it . wrist pin? piston slap? gets it all goes away.sometime gets the sound of detonation .
80-85? That's really low for cranking compression if the test was done per standard operating procedure
If a valve guid is bad , it will make a clunk & knock noise. Not as much at Idile , it's the vavle trying to center its self in seat when closeing . Stethoscope will help narrow down wicth cylinder.
You said it doesn't do it in park or neutral, that means it cant be a lifter or in the valve train. it must be elsewhere. JW
Roller or flat lifters ? Self aligning rockers? Only in drive or reverse , I would be looking elsewhere>
stock hydraulic maybe leaning wrist or piston slap. not much left to do is there for them 2 issue beside major work
Piston slap or wrist pins and excessive oiling at 1 specific rocker are 2 separate and unrelated issues. my foot hurts, I think Ive gotten something in my eye.
checked converter 3 bolts tight and the weight from the factory good. oiling issue now wondering if it was because on a slight slope . haven't tried the automatic case for cracks. just starting to notice a miss. leak down tester the ticket next. just drove to parts store rattled like no other then just comes right out of it. it crazy
I've seen the actual Flex Plate fracture and break out right at the outer edge of the Crank shaft hub. At first sound owner thought it was a lifter, a short time later thought it was a broken piston skirt. It too came and went with dropping in gear and shift point. Seldom at idle in N . Last noise was like a Duck when you step on it's tail. Then it kept running but wouldn't go anywhere. Broke the center out of the flex plate. I have no idea how you would test for that other than physically looking. It was easy to find once it broke out. The Wizzard
I'm confused about your lifter issue as others. Is #1 exhaust working correctly or not ? But that's not why I'm quoting you here. I chased a knock for nearly 2 years. That's right 2 years and this thing never broke or could I find anything anywhere so I said let it blow. It never did. Then one day and why I don't remember but I had the timing light out and was checking where my full advance was. It shocked me to see that it was so high, no super high but did not pinging sound. So I did a test. I disconnected the vacuum advance hose and locked out the mechanical timing and set the timing @ 32. My noise went away. How it never broke a piston I don't know. Maybe because I didn't drive it hard and that it was a stock. But crazy just the same.
You can check the flex plate centre by spraying some penetrating oil on it, if that the problem it will change its sound. JW
flex plate is first thing in the morning so that noise can travel towards the front of engine I guess it can no limitation
A cracked flex plate can drive you bonkers. Yes the noise can travel right thru the crank but it's not a knock sound, it's different. The oiling issue--- Let's use Logic - I know right? The oil is excessive at the rocker that's the obvious symptom. Seeing more oil than you should. Well, That means that the lifter is getting excess oil or the lifter is letting go of more oil than it should. The first option is highly unlikely because it's really difficult to feed it more however it's possible. The second idea that the lifter is pumping excessive oil means that the oil available to work the lifter and keep it pumped up isn't there! it's coming out the rocker. Thats going to leave something makings noise. What up with that low compression
Maybe the front exhaust push rod being furthest from oil pump is the least plugged up and oiling as it should. The Wizzard
Swap a rocker with the one you are concerned about I've had rockers on a SBC shoot oil clear over the finder and the one next to it wouldn't.
man wish I could load up my 15 second videos how about if it was on a small decline in my drive front end lower than the back compression no idea il recheck it make sure that was correct.
A non level surface should not have any effect on cranking compression numbers. A wet dry check will tell you if you have ring issues or not. The Wizzard
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