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Disconcerting engine noise, please help if you can.

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I do have one followup question (sorry if I am overstaying my welcome)... based on discussing this here and with friends, I have received slightly conflicting information and I am hoping you can clear something up. If I pull off one spark plug and the noise changes a lot, what does that indicate? Some folks said that indicates a problem at the crank (and not piston slap) and others said that indicates piston slap or other problem at the piston (and not problem at the crank). When I run this test, I guess I need to better understand what the results indicate so I know what to do next. Thanks.

Well It can be either a piston problem or a crank problem .However, the problem will exist at that cylinder that you removed the spark plug wire from.
 
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Re-read my post. I told you to push down hard on the tappet side of the rocker.
There is a possibly that you could get lucky. If the rebuilder did put the lifters back in the wrong holes, they will go away very quickly. The cam lobes are a lot harder than the tappets and I have seen many cases where the lifters (tappets) went bad because of improper break-in and the cam was fine. If that's the case you can simply install new lifters and then do a proper cam/lifter break-in and you're good to go.... hopefully!
Of course, the best practice would be to pull the cam, have it re-ground to a mild performance specification (nothing over 270 degrees), and then put it all back together with new lifters.
 
Hi Richard-
My reading comprehension is fine. It is my writing skill that could use some work. I am only around the car occasionally when I visit my Mom's. I tried to convey, over thanksgiving, prior to this thread, I coincidentally did try pushing down on a rocker, but on the valve end. So I was lamenting that I was so close to running the test that you ended up recommending, but didn't quite come up with it correctly. I will most certainly run the test you suggest when I am at the car next, which won't be until Christmas or even later. Thanks for your clarifications. I plan to read up on cam/lifter break-in right now. Thank you.
 
It sounds like a piston to me. Could be a broken top ring or a piece of the piston unsettled and tapping the head. I haven't seen a wrist pin fail, but I have seen several piston failures due to detonation/lean running that can lead to this type of noise. Hopefully I am wrong!

Before you head to your Mom's order one of these endoscopes for your laptop or cell phone. They are $15-$20. You can feed it into the spark plug holes and look around, or remove the tappets from the top end and look at the cam lobes. In the final assembly of my overly complicated S38 M5 engine, I dropped a tiny wave washer. It didn't hit the floor. Sure enough it dropped straight into a fuel injection port and it landed right on top of a piston. What are the odds? That $15 endoscope saved me from tearing down and reassembling the motor.

https://www.ebay.com/itm/5-2M-Andro...hash=item5d5c4fab68:m:mp6u701th_plARFSOsP9btg

Not for medical use:smile:

Dean
 
One other (slight) possibility is a loose piece of carbon in one of the combustion chambers. This can occur on older engines and it was not uncommon "back in the day." The endoscope idea is terrific and could help diagnose this problem if you can isolate it to one cyl.
 
Thanks everyone. I now have a great plan of attack for when I am at the car next. I will run all the tests that were suggested and get that oil sample for analysis. I actually have one of those inexpensive usb endoscopes and plan to bring it with me when I next visit my mom. If I cannot diagnose the problem after a long weekend of work, I think the car will be finding its way to a proper mechanic. It will be a few weeks before I get to work on the car, but I will be sure to post any future findings if and when they occur. Thanks again. I really do appreciate all of the help and hope that I can return the favor someday.
 
Shortsguy--

When trying to diagnose problems such as the one you are having I always start with what would be the most obvious and easiest fix.

Do what Richard Mayor suggests and if you get lucky you'll find you have a hung up valve or some other problem in the valve train. Report back.
 
I was in the same situation with a similar sound. It was very pronounced in the cockpit of the car. More when the motor was loaded under acceleration. Pulled one plug at a time and sound went away when the number six plug was pulled. Mine was the rod bearing. Mine was a rebuild with about 8000 miles on it. I had hot lapped road America in a touring event when the sound started. My motor guy really helped out with the re rebuild. We had to turn the crank on that journal to an uncomfortable.060 undersized. All has been good for the past 10,000 miles. Needless to say I don't hot lap the Healey any more. I have more of the .060 over bearings if needed.

if the rockers were brazed closed this indicate to me that the oil pressure was low before they "fixed it" by limiting oil flow at the end of the oiling system. As others suggested have a professional rebuild that too.
Good luck KevinR
 
You can see a few of the rockers are dry. I would take rockers off and look for dry wear and also mushroomed pushrods. looks like the consensus is lack of oiling in upper area.
 
Update:
I got to visit the car yesterday and today and did as many diagnoses as possible. Unfortunately, I was unable to change the noise with anything I tried:
1) I pushed hard on the pushrod end of each rocker and could not get the noise to change.
2) I pushed hard on the valve end of each rocker and could not get the noise to change.
3) I removed one spark plug at a time and the noise didn't change. The engine rpm dropped slightly, but the knocking was the same. I got shocked a few times which was fun.
4) I ran Marvel Mystery Oil in the fuel and oil for only a short drive, but the noise didn't change.

I collected an oil sample and will send that to Blackstone and update this thread when possible. I took the sample before I added any MMO.

I also did a compression check. 145-160 psi cold, dry, all spark plugs out, foot on gas pedal. The all jumped up 5-7 psi if I added a squirt of oil to each cylinder. So compression is okay in magnitude and somewhat balanced between cylinders.

I took off the rocker assembly and some of the rocker pads (at the valve stem) had erosion. I remounted everything and did a valve adjust, and no matter how tight I made those valves, I could not get the noise to change. So while I still think it is valve train related, I cannot figure this one out.

I removed and inspected all the pushrods. They are all straight. None have any damage at the rocker end. All have small amounts of erosion at the cam end.

I took off the oil pan. That was fun. There are several small metallic shards/wires in it and a couple larger chunks of black maybe rust-like material. And lots of little silver and/or reddish flakes.

I cannot see any damage from below the engine. The cam looks fine. Nothing moves when I push on it. But I am pretty ignorant of what I should even be looking at from below.

I will post some pictures in case anyone is interested. The piston faces appear really rough, almost like they are rusty, but that makes no sense since I believe they are aluminum.

Unfortunately, I think the car has beaten my mechanical abilities. I don't know what to do next besides pull the head, and I am probably not qualified to pull the head. At some point, I just need to accept failure and move on.

So I guess my question is: if my next step is to take the car to a mechanic, should I put it all together (oil pan, oil pan gasket, rocker assembly, rocker cover, add oil, new oil filter, etc.) so they can hear it run. Or is it better the leave it in parts so they don't have to waste time taking it all apart again?
IMG_2554.jpgIMG_2562.jpgIMG_2571.jpgIMG_2589.jpg
 
Here is a pic with my cheapo USB borescope. You can see the roughness of the piston face, as well as some scoring on the cylinder walls. Wonder if it is piston slap? The noise is most noticable at idle. I tried to blip the throttle to see if it goes away under load. And it is true that you hear it much less when the engine is above idle, but it may just be other engine noises drown out the knock. I guess my point is, I don't know if the noise goes away when you blip the throttle, or if the other noises just increase in volume and overwhelm the knock.

Also, here is the junk from the bottom of the oil pan. It is sitting on a paper towel folded twice. So the largest chunk of material is about in inch long. Much of it is magnetic, including those little wirey strands. Any ideas what that sort of material suggests has happened to the engine?
C5c.jpgIMG_2595.jpgIMG_2597.jpg
 
Those push rods are junk and the cam/tappets are probably damaged to . The wire is probably from a wire wheel used by the so called mechanic who did the botch job . Basically your looking at a full engine overhaul to check everything .
You will be replacing pushrods and grinding the camshaft replacing tappets and more than likely replacing most of the valve train at a minimum . While it's apart you will need to check the crank bearings Pistons rings etc and decide if they are useable or not . And don't forget to either overhaul the oil pump or replace it as obviously you had oil pressure problems that started the downward spiral in the first place .
 
First, I have never seen anything like those metal pieces in your oil pan. It looks like scrap that came from some place other than from engine internals. Secondly, the rusty looking stuff on the tops of your pistons looks like carbon buildup. And that rocker is ........seriously horribly worn. And is that a photo of a pushrod tip? ... OMG. No way was this a rebuilt motor with only 200 miles on it.
Here's what you need to do next. Remove the side covers and generator bracket and pull out the tappets one by one and check the face that rides on the cam lobe. I believe this is where the problem with the noise will be found. I believe you will find many of them to be pitted and the curvature of at least one tappet face to be worn away to such an extent that it is causing that clacking sound. Please report back soon.
 
I had two engines go bad since I've owned my Healey since 1972. Both had clicking sounds. Both had a bad #6 piston with a beat up/rough piston top where the to piston ring broke and was beaten by the valves. Compression, oil pressure, etc were all normal. I removed the head and oil pan and pushed the piston up through the top and found the side from the top of the piston to the ring groove missing. I'd do this before removing the whole engine. The last time it did it I used a stethoscope and the noise was loudest at #1 piston but the actual damaged piston was #6.
 
Thanks everyone for your amazing help. I didn't expect so many answers so quickly. I checked the appearance of those wire strands from the oil sump and they are not the same as the strainer. But they are clearly man-made as their bend pattern is repetitive. I think the wire wheel hypothesis is dead on.

Patrick's comment about how the sound comes out the front of the engine even if the damage is at the back was very interesting to me. The sound for me (using a stethoscope) is definitely loud at both the front and back of the engine. I suspect the noise travels down the rocker shaft and exits at either end of the tube.

I started to pull the side covers off, but I have decided that, at this point, I need to hand this engine over to a trained professional. I only have a few hours to work tomorrow morning at my Mom's (where the car resides), and I think I will use that time to get the car back together. I have decided that it is probably best that a mechanic hear the noise first hand, rather than just rely on my videos.

So unfortunately, the conclusion to all this is still a ways off. But all the help you have provided has been great. Thanks everyone.

Oh, and I looked it up. The engine and transmission were both rebuilt in 1998. The engine was done at a local shop close to the prior owner. I have the parts list of the work done, and it seems like a complete overhaul with most of the parts ordered from Moss. As you all have figured out, the mechanic did not specialize in British Cars. Since the rebuild, the car has driven less than 4000 miles. Basically, the previous owner still used the car somewhat regularly between 1998 and 2005. But since 2005, the car has only driven 200 miles.
 
Shortsguy

Looks as if you are going to have to get a complete tear down and rebuild with new parts as required, its a shame that you are not engineeringly minded as you could have done most of the work yourself saving mega bucks, is there no Healey boys in the vicinity that could help?

:cheers:

Bob
 
Shortsguy--

Though the junk in the sump is somewhat disconcerting I would not attach any particular significance to any of the detritus. Without knowing the engine's history many things are possible including someone's having tapped some threaded holes with parts in situ resulting in the metallic shards making their way into the oil pan. Or just plain sloppiness on someone's part.

Finding such metallic junk in the oil filter would be much more of a concern and I would recommend that you get into the habit of cutting apart your oil filter on each change and examining the filter medium for shiny flakes (bearing material) and small bits which could be anything from broken piston rings to parts of the valve train, etc.

I would not go to the trouble of reassembling the parts just so someone can hear the engine as it will eventually have to come apart in any case.
 
Bob Hughes said:
... its a shame that you are not engineeringly minded ...
Click to expand...
This should give you a chuckle... I have a PhD in mechanical engineering. But being a good mechanical engineer is rather different than being a good mechanic and extremely different than being a good machinist. Sadly, my time on a lathe or mill can be counted in minutes, not hours or days. And with two small kids, a fixer-upper house, and a demanding University job, learning to be a good machinist is not in my near future. I am sure my students will get a laugh from your conclusion regarding my engineering abilities.
 
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