Rattle in the saddle (detonation?)

DoctorC

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hiya all,
So when I dialed in my Dizzy (viewtopic.php?f=1&t=80088) last year y'all were super helpful.
Now I've gone from the flat valleys of Santa Clarita to the foothills of the Alps. I have a rattle that I didnt have before, or didnt notice. So I made a video of it and I ask that y'all gimmie 2:50 of your time to help me understand if I got detonation?

I'm pretty sure I've had detonation at least once in Santa Clarita, dead stop to WOT there was a gawd awful buzz from the engine. But it was on regular gas @ 120degrees outside. Never had it again after that. I think I did at WOT on the highway when I was tuning the carb+dizzy when I had too much advance. But I backed it off. Until today it's been @ 17degrees (12+5 for the MSD).

But now I'm always going uphill as I live on the hills and work by the beach. And she rattles every day. Now I'm worried I'm killing me engine. Have a look hear on this here video for me and tell me watcha think?

https://youtu.be/mxql46yiZys

Much obliged.
DrC
 
Hi, it is hard for me to hear specific sounds. What I think I hear is valve train clatter. I'm guessing you have hydraulic lifters. Do you have adjustable rocker arms?
Just to be sure, you will not get detonation in park. You must be under load. I find that if the initial timing is too far advanced the engine will ping going up hill in second gear (that had always been my test).
If you think you have detonation I would retard the timing a little and see if it goes away. If you don't have a timing light you can mark the distributor shaft with a sharpie where it meets the engine block. That way you can put it back exactly where it was if you want to.
Good luck
 
Time for EFI !

https://www.vintageinlines.com/product- ... -injection

no, supposed ta B a joke, Matt just got this in (well it would adjust automatically to sea level/tip-top'o da mountain)
:shock:
yeah, I'm the same (just another ol, deaf, bronk driver). Can't hear too good. Sounds more like 'top end'. What is oil pressure, weight of oil, etc. Didn't U have some serious 'blow by' yrs ago (last visit here?)
Ping is a lot like 'pebbles in a can' ( tin-like rattle). Ever hear a motor 'dieseling' (at key shut off - still run)? That;s it exactly (but under load w/key on).
 
hi Guys, thanks for the replies.
Yeah, the blow by I had was wrong PCV hookup (good memory!!) However, I did notice that when i was tuning it the other day I got blow by out the KN filter at around 2k rpm. But when driving that my manifold vacuum (shared hookup to the PCV) seems pretty ok.

And here's my lifters. They dont look very adjustable.

(No comment on the EFI :banghead: :rolflmao: )
 

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:...dont look very adjustable..."
no, not very, a BFH might assist...

I saw no face on yer vid. Do U have long hair?
Some of us use items placed around & on engine components and the other end on the ear - to locate the exact location of bumps, grinds and other shimmy - stethoscopes, wooden dowels, 3 ft screw drivers, justa hose and bananas (no, not the last). We place them around onto the object to dig the vibes (sound that is). This can locate. I have long hair right now - I ask because this is now a dangerous endeavor 4 me & do not want to see a report here that I have caused injury. Rotating prts can really grab (as a machinist I saw a guy's head get grabbed & smashed into a...well. I'll leave it there) and do some damage. But for the adventurous (or safety conscious) it can assist.

When did the sound begin, what oil weight do U use, did the 'retard' assist w/noise reduction?, want some more fun?

U could (if conditions in that pic above still exists) fold, attach, tape. screw or other wise take some (americanese now) 'tin foil", alu foil (capese? camprende?) as a catch tray for wild oil drips and run the engine at idle, hear if the sound is on the top end as I think. Alternately pour 'upper cylinder cleaner' into a running carb throat after a change of filter/ oil to 20w30 or 40 (like a Castrol race oil) possibly available in ur fair country? Report back?
:beer:
 
:unsure: Yes your are correct that valve train isn't the adjustable type, so changing the push Rod lenght is the only means of adjustment. :shock: What's that thing that's growing on top front of the head casting? Hard to tell but sounds like couple problems going on togeather such as a lot of rocker arm noise. The rocker arm assembly may need to be rebuilt or else the push Rod lenght isn't quite right (may be to short) to give the proper lifter preload. Try watching the rocker arms for any bounce or slop on the shaft assembly and also look at the push Rod end with engine idling for extra push Rod clearance. Is there a slight ignition miss going on at idle? Maybe a little vacuum leak sound when you are raising the RPM from off idle, I also noticed some change in vacuum readings (the needle swings back and forth) on your gauge while its idleing. When you are Reving the engine off idle it seems kind of lazy like its laboring. Good thing is that it dosen't sound anything like detonation though with all the rest of the noise going on it's difficult to tell. Most people will never hear detonation at WOT operation. X2 What you should hear if there is a problem is a pinging or rattling sound at a light to medium throttle opening going up a slight grade so that there is a bit of load on the engine. Best of luck :nod:
 
Run higher octane fuel & advise from there. Sounds like detonation.
I set up your distributor for top performance & that requires 91-93 octane.
 
I highly appreciate all the feedback.

-> Fuel: I had about 1/4 tank left and filled up with 98 yesterday to see... no change
-> Hippy hair: Not at the moment... tried it once though. I do not have the valve cover off, but am willing to take it off and check. Last time was to change the gasket and I finally had no leaks afterwards.
-> Vacuum leak: what you hear is the Hiflow filter on the weber... sucks like a hoover and about as loud

"When did the sound begin, what oil weight do U use, did the 'retard' assist w/noise reduction?, want some more fun?"
I've noticed it for a while now, but I had an exhaust gasket leak and since i was always on flat roads, it was never very loud. But now i'm in the hills it's very obvious. I fixed the leak but it didnt go away. Oddly enough, I markedly remember one day a loud tick starting when i was tuning the carb. I seafomed the oil and ran it for 100 miles then changed the oil. But i was not used to the engine and dont rememeber if it was there before I started, but I dont think it was. The Seafoam helped but it never went away. It sounded like a tick from 1 or 2 and was synched to the timing light and followed rpm. Maybe I still have some gunk in there?

The retard made no difference

I want ALLL the fun.

-> Oil: I'll be dropping in some 5W30 synthetic mixed with my one left over quart of dino 10W30. Oil change should be this weekend. Always change the filter when i change the oil.

-> Bouncy vac gauge: The T for the gauge is hooked up to the tranny vaccum which is T'd with the PCV since I removed the carb spacer to fir the Weber. I always assumed this jump was the PCV opening and closing to various degrees.

" What's that thing that's growing on top front of the head casting?"
Cant tell if this is a sarcastic joke about the breather filter or a relevant comment. Will take as a sarcastic comment. It's the +40HP cover accessory i saw on EBay.
 
Your idea on the cause of the bouncy vacuum reading is highly unlikely! The vacuum gauge can be a valuable tool in diagnosing problems with engine operation, in this case it indicates an internal engine problem (a sticky valve?) see the link for Quick reference to vacuum gauge readings. https://www.onallcylinders.com/2016/03/ ... -readings/

That question wasn't meant to be sarcastic and its referance was to the item shown in your above picture of the internal casting under the valve cover (see below) at top of the head next to the rocker arm stand, but okay never mind. Good luck in your quest and hope that you are able to find any problems.

download/file.php?id=4323&mode=view
 
Oh, good call on the vacuum. I love the infographic. Thanks.
As for the stuff growing, I think it's just the rough surface out of focus. Makes it look like mold. It aint.
 
"...the stuff growing, I think it's just..."
yeah, I think I C it too. If it is the same thing - I thought it might B alota bubbles in the oil.
(dont take off valve cover till later in diagnosis. The other suggestions are earlier steps.)
I think the oil still too thin for what I was suggesting (5w; I'm thinkin 20W like 20W 50, the Castrol I mentioned.)
 
chad":a2ty4wuf said:
"U could (if conditions in that pic above still exists) fold, attach, tape. screw or other wise take some (americanese now) 'tin foil", alu foil (capese? camprende?) as a catch tray for wild oil drips and run the engine at idle, hear if the sound is on the top end as I think.

Alternately pour 'upper cylinder cleaner' into a running carb throat after a change of filter/ oil to 20w30 or 40 (like a Castrol race oil) possibly available in ur fair country? Report back?

So Chad, I dont understand the goal in this. Sorry. I assume the first part of you comment is assuming the cover is off.
But the second part. I think you mean like Seafoam. But why the oil change to a heavier weight. If cleaning is the goal, wouldn't i go thinner? They have 40 weight dino oil at my local shup, but I'm running 10W30 at the moment and I unnderstand the goal is to always run the thinnest oil you can get good pressure with.
I must be missing something...
 
"...Sorry. I assume the first part of you comment..."
yes, correct, I thought the pic U put up for a current issue was a current pic. I have learned this lesson B4, "never assume, ask 1st." I should B da 1 2 apologize as I didn't use the admonition. I DID try'n correct w/my comment abt the "don't take off now if back on"

"... I dont understand the goal in this. Sorry...."
good diagnosis. One of the most difficult in the process with the automotive system. Layer into that - that I am not there, local on the ground and my poor diagnostic skill (I am only a Shade Tree Mechanic III, I aspire to #II and know I will never make it to #I never mind ever a Professional). I have a fascination w/systems (a pro at "human systems") tho, yet am not a 'lubrication" expert either.

"...But why the oil change to a heavier weight. If cleaning is the goal, wouldn't i go thinner? They have 40 weight dino oil at my local shup, but I'm running 10W30 at the moment and I unnderstand..."
No, thicker. There are 2 spaces w/in the crankcase-lube-designation. The 1st, 0W, 5W etc is seen by the beginner like me as a 'start up number'. The oil acts like a lil jar of molasses ( my neighbor usta use the phrase "ur as slo as molassis goin upa hill in January"). So low #s are as U say, "thin". The 2nd # is more of a "during running" #. As w/the 1st space (occupied w/the "W") the higher the # the thicker. If the 'sludge' is gone and U bring ina thicker oil it may lower the noise heard (lube beddah) valves. Some of us R uncertain if U have 'ping' or 'clatter" (detonation v top end). A 'listening device' as listed above might assist w/location. Being old (hard of hearing) and ona vid (poor rep of actual events/occurances) makes it tough.
 
Ah, I c. You're suggesting I use a thicker oil to lube better.
Interesting. I'm thinking cleanup, your suggesting lube up. And it might quiet up.
I'm gonna have to meditate on this one. With a single malt.
DrC
 
Kou-well !
me, a number of 1,
can't tell from a vid,
keep talkin tho~
(& experimenting as offered by ALL, he's a pretty knowledgable guy)
 
They make stethoscopes for mechanics. You should be able to obtain one very reasonable. At least then you will be able to locate the area more accurately. Just don't flip out over all the other normal sounds you'll pick up.
 
sixtseventwo4d":n0ssofyo said:
They make stethoscopes for mechanics. You should be able to obtain one very reasonable. At least then you will be able to locate the area more accurately. Just don't flip out over all the other normal sounds you'll pick up.

chrlsful":n0ssofyo said:
...use items placed around & on engine components and the other end on the ear - to locate the exact location of bumps, grinds and other shimmy - stethoscopes, wooden dowels, 3 ft screw drivers, justa hose and bananas (no, not the last). We place them around onto the object to dig the vibes (sound that is). This can locate...
its been a wk now...gone I guess :unsure:
 
Naw... problem still there. Been travelling is all.
Also, I have a more pressing concern. The brakes need their backing plates fixed. The infamous groove in the contact surface... looking at fixing that and the car will be out of commision for a while from one shop to another over the next couple weeks.

I bought the 10W40 oil and have decided to fill the filter with 5W30 sythetic and the engine with dead dino 40. Hopefully that will take care of my tickety tick. I've also discovered that I have a leaky exhaust manifold and my whole carb tuning with my AFR guage is probably off...

soo.... one thing at a time I guess...
 
"... have a leaky exhaust manifold..."
so very often mis-diagnosed as tappet noise
(nother problem even w/an in-person witness)
esp if "justa lill leak". Have fun
(y)
 
Since I thought the problem was my donut gasket I just assumed my tickety tick was the exhaust leak. After replacing the donut is when I came to yall with my issue cuz I thought, therefore, it wasnt my problem.
BUT after using the spray can in the carb with the cleaner whatzit I saw a nasty white plume from the bottom of my exhaust manifold upon accel (lots cumin out the tail pipes too). Makes me thinkey there's a leaky.

And just to skrew me more, one of the bolts on the manifold is broken off already, and the front tab is also...
I would rather take this to a muffler shop and have them pull the manifold and put in the shiney headers I have from VI, but I'm hesitant they'll screw it up worse than I would. So, I'm gonna have to meditate this one for a while. With a single malt of course.

I'm a contemplater. Preferably with whiskey or rye.
DrC
 
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