Valve noise

[TJM70's_48]

I have had my car for just over a year; in that time it has always had a little valve noise while running. Nothing major, but, not perfectly quiet either.

I am one of "not broken, don't fix it" people so I don't want to mess with anything if a little noise is acceptable. But how do I tell what's OK?

I have never messed with valves or much internal engine work on any car. Not that I am opposed to it, but, I'd have some learning to do first. Part of the fun of having this old girl is the chance to maintain her.

I ran the motor at a car show last summer for a guy who also drove a flathead and he said it sounded OK to him. But, I'd like to get a better opinion.

How do I know if I need to adjust the valve tappets? What kind of learning curve is there?

I have the shop manual and read the instructions last night; also have a Motors manual. But I don't have any specialty tools (gauges, valve wrench, ???)

Is this something that I should not attempt myself for a first time? Do I need to get a mentor?

[greg g]

The number one error that people make when adjusting valves it that they set the lash or opening between the lifter and the valves to small. When the engine heats up the gap becomes smaller through expansion and may to 0. this means the valve may not be fully seated in the block when closed.

Keep in mind that the only time the valve can be cooled is when it is in full contact with the seat. So if it does not fully seat, it doesn't get cooled. If it doesn't get cooled it won't take long for exhaust valves to start to melt and errode.

Go to secondhand garage website and check out thier section on reading a vacuum gauge and interpreting the results. Then connect the gauge to the intake manifold and see what it tells you. If you feel you need to adjust them, read the procedural how to that resides in the maintanence section of the main page that hosts this forum.

To access that information, go to the opeing forum page and in the gray header bar on the left hand side push the "return to P15- D24".

[TJM70's_48]

Greg...that's the kind of help I'm looking for...thanks.

Is this the page you meant? http://www.secondchancegarage.com/public/186.cfm

I don't know what I don't know...it makes it tough to do diagnostics. I've always been OK at turning the wrenches, but not so good at determining what course of action to take.

I know it's a learning process -so thanks.

~Tom

Edited May 5, 2010 by TJM70's_48

[boxer_inv]

Tom

I've got nothing of technical assistance to add to your quest, but just wanted to encourage you and say thanks for the way you approached your problem/query. I've learnt from Greg's response too! - now I've got heaps more reading to learn from through that link. Keep us posed if you end up doing some adjustment.

I'm very much a novice to this game BUT am not afraid to get in there and give things a go on MY car AFTER doing MY own research - just as you are doing. "onya - mate!!":D

Question asked...response given...acknowledgement of response...learning outcome... I doubt this thread will stretch to 3 pages.....

[greg g]

Yep you cangain lots of insite into the condition of an egine from reading the vaccum gauge readings.

[TJM70's_48]

OK...vacuum test is done.

I am at 1500 feet above sea level, if that is a factor. According to my specs, this should show about 16 inches to 20 inches of vaccum at my altitude.

At idle, the gauge moves rapidly between a low of about 15 or 16 to a high of around 17 or 18 inches. It's consistent, but difficult to read as it is moving rapidly between the two points on the gauge.

Per my tech data this is most similar to the middle diagram in the service guide: "Rapid vibration of needle at idle speed indicates worn intake valve guides."

Is this what an experienced mechanic would determine from this? I'd be happy to shoot a brief video of the gauge & post it to YouTube if it would be helpful.

If this is worn valve guides, what is my course of action and how fast do I need to tend to this? Can I drive the car or should I get to this right away?

[greg g]

A worn guide will lead to slightly higher than normal oil consumption as some will get sucked along the vavlce stem an into the combustion chamber. It is not a "critical" item as far as operation is concerned. The guides are brass and the valve stems steel, so the guide is actually the wear part in the system. They can be knurled. A process by which a tool is threaded into the guide which raises ridges or dimples effectively creating a new wear surface effectively smaller in diameter than the area that was worn. This process is a stop gap ad it is ulikely you could find any one to do it any more.

[aero3113]

People also think valve noise when it is just the fuel pump arm.

[Dodgeb4ya]

A worn guide will lead to slightly higher than normal oil consumption as some will get sucked along the vavlce stem an into the combustion chamber. It is not a "critical" item as far as operation is concerned. The guides are brass and the valve stems steel, so the guide is actually the wear part in the system. They can be knurled. A process by which a tool is threaded into the guide which raises ridges or dimples effectively creating a new wear surface effectively smaller in diameter than the area that was worn. This process is a stop gap ad it is ulikely you could find any one to do it any more.

Aren't the OE valve guides cast iron except on the big H-duty trucks W/ sodium exhaust valves- those guides being bronze?

Bob

[Niel Hoback]

Flathead valve guides are bronze, I believe. At least they break like bronze when I knock them out the wrong way!

Cast iron guides are for SBC's, not real motors.

[greg g]

I stand metalugically chagrined.

[TJM70's_48]

As I mentioned at the outset of the thread, I'm in a learning curve - so the information is very appreciated. I think I'm going to leave well enough alone...for now.

After I clean up some other house projects, and it's not spring & summer, I may look into learning enough to replace the guides. It's a little bit daunting to think about as a project. Is there anything else that could be learned from my vacuum test readings?

Edited May 6, 2010 by TJM70's_48

[DutchEdwin]

TJ, Yes, there is one more thing, let the engine warm up before you take any conclusion on the readings, but you probably knew that.

[TJM70's_48]

Dutch...I did not know it; so don't assume anything!

If it's not in the shop manual, I don't know it. I don't have a "Homer" (ham radio term...helper or mentor) and I'm going along as I learn, trying not to learn by trial and error when this type of resource is available.

However, in this case, it was warm after bringing her in from a drive. So even a blind squirrel finds a nut, sometimes.

Thanks,

Tom

[Don Coatney]

Not all vacuum gauges are created equal. My engine is "fresh" with new valve guides etc. A couple years back while on a long road trip I connected Greg G's vacuum gauge to my engine and it fluttered same as you describe. When I returne home and connected my vacuum gauge to my engine it was rock steady. I am not sure why Greg's gauge was bouncy on my engine. But you might try another vacuum gauge for a second opinion.

[james curl]

Some gages require a restrictor to dampen the pluses. I have a fulltime vacuum gage installed in my 55 chevy pick up, installed a motor meter vacuum gage during the gas shortage in the early 70's to try to get better gas milage. Back then they suggest that you drive like you had an egg between your foot and throttle pedal. Almost any movement of the foot feed moves the needle a long ways toward 0" of vacuum.