I mentioned this problem in another thread a few days ago, but I figure it would easier to start a new thread for a different problem.
I get am getting a knocking noise that is hard to hear when standing over the engine, but it is very prevalent in the cab.
The first video is standing over the engine (idle has been turned down since taking video)
The second video is the from inside the cab.
Some information on the noise, it is there from the second I start it up, until I turn it off. Driving around and letting the engine heat up has no effect on noise.
If your tappets are set right, and your oil isn't super thin, or diluted with gasoline (washing down the cylinders from an overly rich mixture, or shot rings), you might want to drop the oil pan and check the clearances on your con rods, and mains.
hard to tell over the video. change your oil (don't use synthetic), check rocker lash (when warm). if it's still knocking i'd pull the oil pan..sounds like a rod bearing going out.
all of the journals on your crankshaft have bearings, i.e. 4 main bearings on your main caps and 6 rod bearings on piston rods. If your bearing has failed already your crank or rod is probably scared pretty bad and maybe need to be machined.
If you are getting gas in the oil, it will smell like gas (alot).
You might want to read the shop manual for the truck. The engine section starts with a description of the engine, and has lots of great diagrams and pictures.
i don't think its your rockers or lifters, i think you've got a bad bearing. If you arn't too mechanically inclined i don't recommend you investigating under the oil pan without someone who is. Just removing the oil pan isn't going to show you too much, the caps need to be removed, and if its not the caps, its your main bearings and that means you have to pull the whole crank. If that's the case a rebuilt might be in your future.
Bearing noise is almost always affected by engine temperature. As the oil warms up and the oil thins out they will get noisier. He stated the noise is the same cold or hot. I would sure start with the easy job first, adjust the valves.
Hard to really tell over video, but to me sounds like rockers badly out of adjustment. Set you valve lash first. If it quietens down, good on ya. If not, then time to get serious about dropping the pan.
I think the cab kinda filters out some of the quieter rockers and the louder ones are more prominant.
How long has it been sounding like this?
A bad rod bearing will get steadily louder as the engine is run and then fail. If it has been run a good bit without getting any louder, then likely not a rod, though a main bearing can knock a good while. But a main bearing usually has a deeper thump sound to it. I know, not a good description.
But does sound like valves needs adjusting to me. Good luck.
Before you get carried away. Use a broom handle and touch all over with one end and listen on the other. I don't hear anything on the first video. The inside cab video: I hear an exhaust leak. A stethoscope is nice to have also. HF has them. Yes when they say "mains" they mean main bearings, crankshaft bearings. Yes when you pull the oil pan you can see the bearings.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
I bought the truck a few months ago, sounded like that when I bought it.
I have not seen a visible exhaust leak... where should I be looking?
As for being mechanically inclined, I am pretty good with my hands but I have zero experience with internal combustion engines... I will take a jet engine any day though.
Just to be clear, when I set the valve clearance I keep the engine on?
As for the "thump sound" the video does not do the sound justice. It sounds like someone it hitting the firewall with a rubber mallet.
If you can handle a jet engine, with the right repair manuals you should be able to handle the old six. If you have a friend that does mechanic work, he can help you.
As was suggested you can take a sawed off broom handle and listen to the side of the block to try to narrow dwn where the sound is coming from. Put one end to your ear, the other to the bock just below each spark plug.
If it is a rod bearing, a lot of times if you remove one spark plug wire at a time when you get to the loose rod it will quieten down some. That will be the one that is bad.
When you remove the plug wire, if it doesn't quieten the knock, put the wire back on the plug and go to the next one.
If you pull the oil pan, and look inside th engine, you will see the rod bearing and main bearing caps, but won't see te bearings until you remove the caps.
Sounds are very difficult to describe on the written page or verbally. To one person it might be a tap, to another it might be a thump, and on and on. If the engine has a good many miles on it the main bearings are probably worn and you will hear a dull thump when you first start the engine because the crankshaft isn't yet supported by the oil pressure. This usually quiets down after the engine starts and the oil pressure starts to show on the gauge. There are ways to isolate a loose connecting rod (rod knock) but I would agree that the best way to isolate where your noise is coming from is with a stethoscope. This discussion on engine noise is very well done and may help you . But as is pointed oout even for an experienced mechanic engine noise can be a tough nut to crack. http://www.supramania.com/forums/showthread.php?20486-Rod-Knock-Diagnosis-and-FAQ Unless the truck has had someone that took good care of it and gave it all the required maintenance over the years you most likely have bad motor mounts . This usually results in the engine sitting unsupported on the cross member because the rubber has turned to jelly. That can transfer a lot of the engine noise into the cab. As far as setting the valve lash or adjusting the rockers or valve adjustment (all the same ting) there are a number of instructions here on the ‘Bolt that describe how to do it with the engine off once it is warmed up. Some people prefer to adjust the valve lash with the engine running. That is a bit more difficult but it assures that they are all adjusted at the same temperature. It could take fifteen minutes to a half hour to adjust them and with the engine off that’s enough time for the last valve to cool down a lot more than the first one. Properly adjusted, a valve train with solid lifters will have some high-pitched metallic sound similar mama’s sewing machine.
Don’t rush into tearing your engine down if it’s got good oil pressure and running ok. These old Stovebolts will run for a long time even after they are well worn. To cure your oil burning your only option is to have the engine rebuilt, which will run you somewhere around 3k.
I used these instructions when I set my lash with the engine off. (But engine hot after long drive) ...link...
I would really like to see a video of someone setting the lash with the engine running.
I young guy was walking around the nieghborhood and heard my truck running. I had the hood up parked in front of the house. He asked me whats wrong with my engine.
You can't see an exhaust leak unless it smokes and that could be an oil leak. Hard to "feel" it because of the fan. If you're lucky it's an easy mechanical fix, exhaust leak, vibration (as mentioned) or normal noise. The louder the sound, the easier to find. If you're unlucky, just buy a used engine. One that you and a mechanic can listen to, check oil level, oil leaks, oil pressure,compression and maybe even drive it around under load to test it. You can buy 5-10 of those for $3K. If I were you I would buy a more modern engine. The AD guys here will tell you which ones fit. More power, better bearings, reliable. Chevy made some nice 6's in the mid 50's-60's and up. If you are a person who wants your truck to be totally original, buy a used one from that era. Denny says they last a long time so you have got a good chance to find a good one. A guy could to tear it down and then say you need a new block!, parts and labor are way high. Finding a guy who really knows what he is doing is not easy. Rebuild is sometimes a real PITA. For a total restore you need to have a "new" engine. You don't want to do all that work and have a used engine, But are you in that category? Buy a cherry picker and pull it out, very easy and mechanically straight forward. Keep all the parts that you can unbolt and $crap the rest. (IF someone says it's bearings or worn engine parts.)
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
Well if I weren't so dang busy with trying to make some sort of sense out of 40 years worth of collecting that I've got piled up from the move this summer, and if I had three hands, 2 to adjust the valves and one to hold the camera and if I knew how to take a video and knew how to post it.....takes a breath....I'd post one for you to see Gus. But here’s an old Jam Handy film strip of a guy tuning up the valves on a running Stovebolt engine at the factory in the 30’s. Skip down to 3:25 minutes on the video to see that part.
Also around that part of the film it shows a guy with a prop who is listening to the engine for noises. Pop taught me that was the best way to adjust valves more than half a century back and that’s the way I do it now. Here’s a fuzzy picture of the New Britain valve-adjusting tool that I’ve been trying out lately. Never had one of those back in the day, a stubby screwdriver and box wrench always worked for me. http://www.pbase.com/dennygraham/image/136174534
Denny I have a similar tool as the New Britain valve-adjusting tool. Except mine was made by Zim. It's what I use when I have the engine warmed up and running to set the valves. I adjust them by (ear) same as you and your Pop. I'll use feeler gauges to cold set the valves, but then it's Zim's turn.
Thanks for the link Denny. I was wondering how it was done running. Looks easier without a fender in the way and in the shop. I'm vertically challenged and diameter impaired so leaning over the bay didn't seem like a good idea with the engine running.
I'm going to give that a shot next time. In my mind all I could see is smashing feeler gauges.
I've been using the pointer on ball method (1 and 6 firing) but that seems to be frowned apon here.
Yep, I ran into those way back when I was looking for one of them Tim. I noticed then that the Zim tool is identical to the New Britain tool. Zim is still making that tool to this day.
Oh yeah, before I forget, I've never hammered a feeler gauge out of shape while adjusting valves. If you do that you're cranking them down WAY to much. DG
just drive the crap out of it, if it blows get another engine I had a noise in my van once, just drive it... could not make it go away or blow the engine...drove it that way for 2 yrs and sold it...
Redryder pix My Hotrod A veteran - whether active duty, retired, national guard, or reserve - is someone who, at one point in his or her life, wrote a blank check made payable to The 'United States of America', for an amount of "up to and including my life." I am fighting cancer and I am winning the fight | Pain is part of life; misery is an option.
Back in high school in the late 50’s the little band of bad guys that I hung around with, cruised around on Friday nights in a 49 Chevy 4dr stick shift. Back then you could find an old Chevy beater for fifty to a hundred bucks. Craig, the guy that owned the beater, worked construction so he had money to burn and didn’t really care if he burned up one beater, he’d just go out a pick up another. One Friday night we picked up our case of beer at the Old Mill Tavern and were cruising around in the country sucking up suds and for some reason, probably because the shifter box was worn, it got stuck in first gear. So he just drove it around the rest of the night in first gear, wide open. Once when we stopped to tap a kidney the old 216 was steaming like old faithful and when we popped the hood the exhaust manifold was glowing bright red. Craig went on to drive that old Stovebolt for the rest of the school year to work and all, and it never did give up the ghost that I can remember. They will take one ell of a beating and keep on tickin’.
That's right, run it, enjoy the sound. That sound is the sound of the good old days. All you gatta do is keep it oiled. I had a 56 Chevy 2 dr 265 V8 that smoked so bad I used 90 wt gear oil in it. Ran til I wrecked it. Is that RTIWI?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
I just got done adjusting the valves and it sounds 100% better. There are still some that are off a little but I no longer need ear plugs in the cab.
Also, in the process of idling for as long as I need I got more information on the oil problem. I probably had the truck idling in the garage for an hour, and when everything was all said and done there was oil and water right below the exhaust outlet. Any ideas?
The combustion process produces a lot of water, it's normal for water to condense at the end of the "tail pipe". If you have some oil vapor condensing there also them it's just telling you what we have been saying all along, you are probably in need of an engine rebuild if you want to stop the oil usage.
You are at 20 lbs from highest to lowest. Some books say should be less than 20 lbs diff. You're not terrible, but tolerable. Take it three times and make sure the throttle and choke are WIDE OPEN!! A 1949 216 is 110 lbs new according to the web. Squirt two squirts of oil into cylinder on test three. I assume a 216? I re read the post, no one ever said what engine this is? Can someone state what engine? Does it have babbit bearings?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
If you are going to run it til she gives up, you don't need to get more readings. I just thought you were still working on her. I read your other post now. Keep her oiled and take it easy. Don't fret over the engine. Do a swap when your ready. It's a nice looking truck! Fun I'll bet. Later.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
In my experience,"rod-knock" is usually more prevalent when engine is idling. If bearings aren't too-far-gone,the rod knock will be substancially quieter,or dis-appear when "under-load" If the knock quiets-down, when you let the clutch out,with your foot on the brake, the crank MAY be salvagable,so shut her down,pull the pan, remove,(in sequence),mark,(with masking-tape,and "Sharpie"), all the bearing-caps. Check the bearings,and the crank for scoring. Even if crank "looks O.K.,I'd still plasti-gauge the journals,to make sure they're in tolerance.you put the gauge between the bearing and the crank,torque the bearing to spec's,loosen,and remove cap,and the "spread" of the gauge reflects the clearance between the two. Test and record all bearing-caps' measurements. If crank is still "in-tolerance",I believe,(Not 100% sure),that you may drop the crank,(May need to jack the engine for this). If the journals are slightly scored,but not grooved,or gouged,i have been successful,using emery cloth to restore the surface. Just make double-sure surfaces are surgically clean before re-assembly. This will help prevent pre-mature wear,which would bring you back to this post way too soon. Hope this helps.
