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loud enguine- valve like

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AH67

AH67

Senior Member
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Hi all,

My 65 BJ8 was frame off restored including engine rebuild. Car runs immaculately expect for the loud and unusual what seems to be un-adjusted valves. Three shops and attempts the valves are adjusted but the loud unusual noise persists.

Engine has less than 500miles on the rebuilt.. So what could that be if not the valves..
 
Clutch plate installed wrong.???
 
Keoke said:
Clutch plate installed wrong.???
Click to expand...
That should not make any noise with clutch released...if wrong, only when disengaged and rotational speed difference between the parts.
Use a piece of fuel line and listen to the areas you think it's coming from.
Could be dished tips on the rockers that were not addressed in rebuild. Either catching the end of the stem or preventing proper feeler gauge insertion. I have for sure seen that in a lot of various vehicles over the years.
Rocker cover off, engine running, do all the rockers oil properly?
Loose guides. Improper valve springs (coil bind?) or shims. Wrist pin? Piston slap?
Broken rings?
You may have to pull the rocker shaft off and actually look at the end of the rockers. Let's say they have a .010" dish....and you set them to .006".....and now it's .016" and going to make quite a noise.

You won't have the issue, but I had cams 30 degrees advanced on my Jag, and for the 8 years I have driven it (and not able to find a loose valve lash anywhere) it ended up the noise was the valves impacting the pistons.

Distributor bushings. Loose flywheel. Pickup tube on oil pump hitting the rods.

Hook up a timing light to any plug, watch the light (at idle) and listen. If the knock comes every flash, valve train. If double that, head gasket downwards.
 
Any way to attach an audio or video clip so the experts can hear it?
 
Does sound valve train-ish with maybe some exhaust leak thrown in.
Again, timing light to make sure.
Look for dry rockers.
FEEL the rockers at both ends lightly with engine idling and of course, rocker cover removed. You should be able to feel any that are making noise.
Then engine off, remove rocker assembly after marking suspect ones with chalk or tyre crayon, and look at the pushrod end, both ends of the rocker, end of valve stem, and then work the end of the vales in all four compass points to see if a guide has perished.
I have a letter in my filing cabinet from NASA telling me this is NOT rocket science.
You'll find it.
Oh...and before you tear down rotate the pushrods to make sure you don't have a bent one hitting the head.
 
TOC said:
Does sound valve train-ish with maybe some exhaust leak thrown in.
Again, timing light to make sure.
Look for dry rockers.
FEEL the rockers at both ends lightly with engine idling and of course, rocker cover removed. You should be able to feel any that are making noise.
Then engine off, remove rocker assembly after marking suspect ones with chalk or tyre crayon, and look at the pushrod end, both ends of the rocker, end of valve stem, and then work the end of the vales in all four compass points to see if a guide has perished.
I have a letter in my filing cabinet from NASA telling me this is NOT rocket science.
You'll find it.
Oh...and before you tear down rotate the pushrods to make sure you don't have a bent one hitting the head.
Click to expand...

I had a dry rocker and it would make a startlingly loud clattering noise on and off. Like someone was hitting the engine with a hammer.
 
AH67:
Below is a link to a thread of mine from a while back, trying to diagnose a somewhat similar noise. You can read all the great suggestions of others and see if any relate to your situation. In my case, the noise was due to pistons scraping on the cylinder walls, caused by insufficient clearance. The clearance problem was likely due to chronic overheating (or acute overheating), but may also have been due to poor decisions by the mechanic during an engine rebuild.

https://www.britishcarforum.com/bcf...oncerting-engine-noise-please-help-if-you-can

I hope your issue is valve-train related, as the resolution is likely to be cheaper and easier.
 
I don't think it's a good idea to run and engine that sounds like for any longer than necessary. You could remove the fanbelt and see if that stops it and you could remove the rocker shaft and pushrods, take off a tapper cover and lift a few tappers to see if the cam and tappers have worn out.

you probably need to pull the engine and carefully strip it out.
 
Well, since he's already taken it to two shops to have the valves adjusted or find the noise, I think any advice of not driving it may be a tad late.
And unless the engine has grenaded, I personally want to try to locate the source and cause of the noise as closely as possible before a teardown that officially means the end of listening for any noises with the engine running.
But, if we need to go down this path, just replace the coil.
Nobody believes in logical step-by-step troubleshooting anymore, or following any kind of preliminary guidelines and reporting back so the path can be adjusted to get us all to the source of the problem.
So we just follow the "common wisdom" and replace the coil, mark it fit for duty with iodine, and off we go.
Done.
 
TOC said:
Well, since he's already taken it to two shops to have the valves adjusted or find the noise, I think any advice of not driving it may be a tad late.
And unless the engine has grenaded, I personally want to try to locate the source and cause of the noise as closely as possible before a teardown that officially means the end of listening for any noises with the engine running.
But, if we need to go down this path, just replace the coil.
Nobody believes in logical step-by-step troubleshooting anymore, or following any kind of preliminary guidelines and reporting back so the path can be adjusted to get us all to the source of the problem.
So we just follow the "common wisdom" and replace the coil, mark it fit for duty with iodine, and off we go.
Done.
Click to expand...

Yeah, I'm finding this to be true, more often than not anymore. I also follow another BB, that deals with another make that I own (from another country), and have wasted a lot of time trying to convince this guy that his electrical problem is a actually symptom of another problem. He's asked about three times if he can just replace the blown item with another new part-which hasn't worked at least twice. I keep trying to explain why the next new one won't probably work either, and what to look for that is causing the new parts to fail. I've now given up, since he's apparently not getting the answer he wants.

Back to the original question: The noise may or may not be a terminal thing. The suggestion of using a timing light to isolate a top end or bottom end problem is an excellent one. Once that is done, if it is in the valve train, then proceed with trying to isolate which valve or cylinder is the source. Lightly placing a finger on each rocker arm, and finding which one syncs with the click also works (Disclaimer: Don't try this at home, YMMV, etc!). If it's the bottom end, then it might be time to tear it down.

Years ago, I never could get the valve lash to be correct in my TR4, and it rattled and clicked. Drove me nuts. Turned out to be the rocker bushings and the shaft were worn, AND the face of the rockers were dished, as one poster already suggested. Rebuilding the rocker assembly solved the problem. Checking for a bent push rod is also a good idea; but WHY did it bend?

Another time, a friend (we were in high school, so no further explanation is necessary!) shaved the head on his TR4A to raise the compression. It ran like crap, and made all kinds of noises. We later found out from the "old guy" (probably about 40 at the time) that ran the local import shop, that the push rods needed to be shortened by the same amount that was taken off of the cylinder head's face, or the rocker arm geometry would be altered so much that the valve train couldn't work properly. This was actually described in the Performance and Tuning section of the Robert Bentley manual that I had. The car ran fine once he fixed that-wasn't much faster, though.

Good luck. I wouldn't panic yet, but don't run it any more than is necessary for troubleshooting until you have more information. Jim
 
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It's easy enough to drop the sump too and check big ends and the two centre mains. IMO a coil will make no difference.
 
Check with a hose or screwdriver or stethescope to see if noise is on top. If on top may not have installed pushrods in proper places or rockers. Needs cover off and an eyeball check of oiling and a finger or thumb on rocker one at a time to see if it quites it. If noise is in front would be timing chain. If noise in pan would be rotating parts. Good luck.
 
AH67 said:
here is a sound clip https://drive.google.com/file/d/0B3MA1fP4bETJVXVwX2lJY2ptaHM/view?usp=sharing
Click to expand...
Definately sounds like valve train. Although there does seem to be a hissing noise as well which could indicate water pump or generator issues. Does it sound the same when cold as when warm? What oil are you using? A thinner oil may well give you more valve noise. I would try a stethescope to see if you can narrow down exactly where the noise is coming from. If you don't have one, take a long (socket) extension and hold it against different areas of interest, put your thumb over the end of the extension then put your ear against your thumb. It won't be as good as an actual stethescope but it will do well enough.

Cheers,
Dan M.
 
Let me know when you find out what it is, I have a similar tick and it is not the tappets - gone over them so many times and the engine has done some 4000 miles since the rebuild and some of it at around 100MPH. The noise just fades into the background when you are going.

:cheers:

Bob
 
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