Valve train noise of my very own!

E

Explodedscout

New member
Greetings all!
I have a 1968 Scout 800. Tapered 44 rear axle, and I think 27 front axle. Three speed stick. Stock fuel and ignition system. Initially it came with a 266 but now it has a 345 IH of unknown origin. It sat for 3 years in my yard before I got to it, and who knows how long it sat before I bought it. Yep it has a ticking noise. I put a cut away valve cover on it and the noise maker appears to be some part of the rocker set up on the driver's side, second one from the firewall , if that matters. On a cold start the offending rocker is not the first to start oozing but is only a few seconds behind, and is on par with about half of the other rockers. It appears to be "rocking" less than the others, but that might be my imagination. When I apply the hammer handle to the pushrod side of the rocker the tone/volume of the tapping is little changed, but when I push on the spring side of the rocker (hard) the noise disappears for about 6 seconds. During this 6 second interval, the engine sound changes (rougher/worse). Just before the ticking returns the idle smooths out. This effect was repeated every time I tried it. Pushing on the adjacent rockers makes no difference. I was able with a little effort to get the pushrod out and to my untrained eye it does not show any blatant damage. The rod is a ball/ball type that is 9.75 inches long. With the pushrod out, the rocker arm swivels freely on its shaft, and again the contact areas on the rocker do not appear beat up. The ticking noise is fainter at start up, but the time it takes to get louder appears to be getting shorter with each time I run it. It is on stands, so I have only had it above idle occasionally. I did whack the gas a few times to see if increased revolutions might make some kind of difference but it has not seemed to. I felt around the spring and I can't feel any brakes in it. It has had 7 quarts of 10w-40 oil in it the whole time, with a new nappa gold oil filter. Most of the info appears to be for non-oiling rockers but it does appear to be oiling. Is it perhaps not oiling good enough? Should I take off the spring and check out what I can of the valve stem? Try and fish out the lifter and inspect? I feel like I'm getting close, but I need a direction for the next few steps. Thanks for reading.
John
 
Not sure of your location and the associated climate but 10w-40 would be considered by the majority of binder owners to be a bit on the runny side for these engines. Straight 30 weight was the original call out back in the day. Nowadays, 20w-50 in moderate climates or 15w-40 in colder climates are the most popular choices. That coupled with the use of a quality oil filter such as a wix, baldwin, or hastings is a very good idea. This is not to say that switching in your case will be the holy grail soltuion to your issue. I suspect as you do that there is a mechanical cause responsible for your issue. You've come to the right place for diagnosis and you've already taken some good and logical steps all on your own. I'm not the one to give you your next marching order, but rest assured its coming.
 
explodedscout said:
greetings all!
I have a 1968 Scout 800. Tapered 44 rear axle, and I think 27 front axle. Three speed stick. Stock fuel and ignition system. Initially it came with a 266 but now it has a 345 IH of unknown origin. It sat for 3 years in my yard before I got to it, and who knows how long it sat before I bought it. Yep it has a ticking noise. I put a cut away valve cover on it and the noise maker appears to be some part of the rocker set up on the driver's side, second one from the firewall , if that matters. On a cold start the offending rocker is not the first to start oozing but is only a few seconds behind, and is on par with about half of the other rockers. It appears to be "rocking" less than the others, but that might be my imagination. When I apply the hammer handle to the pushrod side of the rocker the tone/volume of the tapping is little changed, but when I push on the spring side of the rocker (hard) the noise disappears for about 6 seconds. During this 6 second interval, the engine sound changes (rougher/worse). Just before the ticking returns the idle smooths out. This effect was repeated every time I tried it. Pushing on the adjacent rockers makes no difference. I was able with a little effort to get the pushrod out and to my untrained eye it does not show any blatant damage. The rod is a ball/ball type that is 9.75 inches long. With the pushrod out, the rocker arm swivels freely on its shaft, and again the contact areas on the rocker do not appear beat up. The ticking noise is fainter at start up, but the time it takes to get louder appears to be getting shorter with each time I run it. It is on stands, so I have only had it above idle occasionally. I did whack the gas a few times to see if increased revolutions might make some kind of difference but it has not seemed to. I felt around the spring and I can't feel any brakes in it. It has had 7 quarts of 10w-40 oil in it the whole time, with a new nappa gold oil filter. Most of the info appears to be for non-oiling rockers but it does appear to be oiling. Is it perhaps not oiling good enough? Should I take off the spring and check out what I can of the valve stem? Try and fish out the lifter and inspect? I feel like I'm getting close, but I need a direction for the next few steps. Thanks for reading.
John
Click to expand...

Very nicely done diagnostics john!

This one is acting a bit different from the norm per your description. And the ball/ball pushrod tells me ya gotta "boat"-style rocker assembly.

When you apply pressure to the valve spring side of the rocker, you are causing the valve itself to momentarily not completely close, thus the change in engine sound and stagger, that replicates a leaking valve which is not the root here. And doing so allows the lifter to "extend" ever so slightly which then takes up the tiny amount of additional slack in the system for just an instant. Then when you release the pressure, the lifter bleeds off to it's normal operating length, but it May not be holding proper pre-load internally. But don't condem the lifter right now until ya do the following steps. So...I have three things to look at for this one:

1) remove the entire rocker assembly, then remove the offending rocker arm and carefully inspect the wear pads on the boat rocker and on the rocker shaft at the contact points. If those wear points are excessive, the ability of the lifter itself to "compensate" for the overall change in pre-load on the lifter would be root cause. The boat rocker assembly is simply very sloppy when new, the combination of shaft wear and rocker wear over time simply can't be compensated for by the lifter (my opinion).

2) remove the offending valve spring using an air hold and a spring compressor for removing without removing the head. It's possible that the spring itself has collapsed though that would be very unusual on one of these engines. Simply install another spring (known good) and then test the system again for any change.

3) the lifter itself May have a problem (sludging and contamination). I don't normally point a finger at a single lifter itself but it's entirely possible. So pull that one lifter out and inspect the base for extreme wear, then carefully disassemble and clean and see if anything strange is going on inside. If the lifter base is worn, then that points to a bigger issue which is a cam lobe/lifter interface problem.

As trev alluded to, oil viscosity is not the issue here, those lifters will run on anything!

You have done a nice job in working through this systematically, continue to do so and you will get to root cause!
 
Thanks for the replies!
Hopefully I get this posting pictures thing right.

Ok, here is a photo of the offending lifter in the center.

rockers.jpg


One of just the shaft.

shaft.jpg


And one of the shaft viewed so that perhaps you can see the slightest wearing along the top profile, just to give you an idea of the level of wear.

shaft_2.jpg


I do not have any experience to judge an acceptable amount of wear, but all but the end rockers seem to be about equal. The end ones don't seem to show half as much use. If I had to pick the most worn one, I would choose the noise maker but it's darn close.

I haven't had the chance to remove the spring, and it May not be necessary because when I fished out the lifter, the part that rides on the cam is 'dished'. I get the impression that it is supposed to be flat. I have not done a search to find out because I'm a little pressed for time. Neither did I pull out any of the others (pita) but can if it serves a purpose.

lifter_2.jpg


lifter.jpg


So go on with checking the spring, and lifter disassembly? I will do some more research later, and might find the answer. I just wanted to post and keep the ball rolling. Thanks guys.
 
Rockers and shafts look typical for usable parts..

Lifter : toast
cam: toast.


Just an observation.
That small depression on the lifter face is not however typical for a lifter and cam that spent there entire life together.

Most likely the lifter was replaced on a badly worn cam in a sad attempt to save the cam. In a normal situation the dish develops across the entire face as the can wears out and gradually deepens till it starts to make a racket.

The picture I attached is of 2 lifters that lived on the same cam for there entire life. Pay close attention to the curve and depth of the dish on the two. While one is way deeper, the dish extends across the entire face

also note the wide polished area on the ones I posted from a long life as opposed to the narrow wear band on the one from your picture.
 

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Well nuts.

Looks like I will be slapping it back together and getting a loud stereo. Replacing the camshafts is in neither the time nor fiscal budget. Am I risking catastrophic failure with this course? Don't get me wrong. I love this little truck...I would just love it more if it were rolling.
For future reference, once you have the engine apart that far it only makes sense to replace both camshafts, but if money were a huge object, is it unheard of to just do one?

Confession time:
I might drop a new lifter in there. With as much as I plan to use it, if it gets me say, 10k noiseless miles, that might translate to 3-5 years. Don't worry. It hurts me more to do it than it does for you to read it. Ha, ha. Man I hate doing a half fast job.

You people have been really great. Thank you for you time!
John.
 
Not only is the cam/lifter deal bad, so is the "boat" style rocker shaft/rocker assembly! If you can see the wear it's excessive, and I can see it both on the shaft and in the rocker.

See the latest post in this thread for a referral regarding the same issue:

http://www.forums.IHPartsAmerica.com/gas-engine-tech/4700-stock-pushrod-length-304-a.html

Trust me...you are not alone regarding this issue! If you read through the threads in this section of the forum you see just a tiny sampling of posts regarding this issue. You should see the volume of individual email strings I receive regarding the same thing from folks who don't wanna discuss in public!
 
sdowney717 said:
it will work.
People drive around all day long with worn parts.
Click to expand...

Total bullshit statement!

Obviously you don't have any experience with the IH "poor lubrication to the valve train syndrome". And the resulting on-going "lifter noise" which has it's root in crapped cam bearings.

We've put hundreds of hours of time over many years in developing this information posted here on this forum just to repudiate statements like this!
 
I did not say it would work for ever, it was running before he took it apart. As far as the engine grenading itself, I dont think so.

am I risking catastrophic failure with this course?
Click to expand...

Whenever and if you decide to or are forced into fixing it, you likely will tear it all down anyway.
 
The "don't think so" is not a helpful bit of advice.

The fact is that at least one entire system of components seems to be well past the glory days. Exploded doesn't know anything about the lower end of the motor, except that it seems to all be there. Remember, with the "right" kind of previous owner, anything is possible! I would recommend a minimum of dropping the pan to check for foreign objects, that can cost you as little as the price of one pan gasket and an oil change Unless you're really attached to the used fluid or you see a sign from above in the varnish.

Also, there is only one camshaft to replace... Plus 5 bearings and 16 lifters, you shouldn't swap in a cam without replacing those. Concerning the upper valvetrain, it's likely that the guys at ihon can piece together a set of only those parts which need replacing. I'll vouch for the fact that they don't try to screw with ya!

I'll be crossing my fingers that your rig (like mine) holds together until the time it can really feel the luv it needs, because we like seeing these things last forever - it makes the "other" guys wanna convert!
 
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Many people are just getting by, out of work and no money to spend. The cheapest solution for them is too let things go until they go and then just get another cheap used car or truck. I personally cant stand it when something is making noise. The only car I let slip was an older GM diesel wagon. We drove that into the ground. Eventually it split the crank in half, so when you cranked it, the engine spun but the front of the engine did not turn.
 
sdowney717 said:
many people are just getting by, out of work and no money to spend. The cheapest solution for them is too let things go until they go and then just get another cheap used car or truck. I personally cant stand it when something is making noise. The only car I let slip was an older GM diesel wagon. We drove that into the ground. Eventually it split the crank in half, so when you cranked it, the engine spun but the front of the engine did not turn.
Click to expand...

This bullshit addition to an existing thread has nothing to do with providing technical assistance for the subject matter posted by our member.

Simply "letting this go" is not a solution for anyone requesting assistance in these threads and posts. This is not some kind of game with us here at ihon, this is a business where we do whatever we can to take care of our customers. There are other forums where crap like this can be bantered around all day and all night for finger exercises.
 
He already said he was just going to put it back together and fix it at some future time.
So he is not interested in any more technical help right now.
well nuts.

Looks like I will be slapping it back together and getting a loud stereo. Replacing the camshafts is in neither the time nor fiscal budget.
Click to expand...
 
sdowney717 said:
he already said he was just going to put it back together and fix it at some future time.
So he is not interested in any more technical help right now.
Click to expand...



You have to differentiate the right of an owner to not fix it and risk catastrophic failure from supporting that it is sound advise to do so...

He absolutely has the right to stick it back together and run it till he can afford to fix it right.... If that is all he can do so be it. Just understand that recommending that that route is fine is irresponsible and in a very technical sense just wrong.

When the lifter finally decides to shed metal like a grinding wheel the filter will plug up , begin to bypass and along with the bypassed oil goes all of the metal. More than likely the bearings will be wiped out along with the crank. Wow that is a lot of cost that could have been avoided if only the thing had been fixed right the first time.

We try to point people in the best technically responsible direction. Never down a dead end road.
 
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