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Just changed my timing belt, now I hear a slight tapping under the hood. Its possible and I am hopeful that I just did not notice this before.
Seems like I hear it at an idle. Also when I rev it up it goes away, but seems to make it again as the RPMs die down.
Does this symptom sound like piston slap? Its not especially loud but I definitely hear it in there. Or could I be off a tooth on the timing belt? Car does not miss or seem underpowered when driving? I had assumed that I would definitely notice a difference driving it if the timing was off.
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I listened to you post on YouTube.
Despite the wind noise and the whine from revving, I could hear a slight noise of tapping.
It does sound like a piston ticking.
In my experience that noise does go unnoticed when the hood is down and more so if you are in the divers side of the cabin. To me it's louder from the exhaust side. I think because it's more open on that side of the engine.
Having it parked in between garage walls helps drive you even more crazy than the hood being up!
That ticking noise should go away after you have driven the car for awhile or at highway speeds. More so because ALL of the engine components have completely warmed up.
I say this because in most cases the piston has gone round or is worn more round due to the side loading of the piston perpendicular to the wrist pin.
A Crankshaft grows bigger and longer.
Until things are back to a place they have worn too, expect some variations of noise.
Well design Engines can and do grow old gracefully!
A wrist pin can create a noise, sounding, very closely to this as well. Just needs to get just a tiny bit loose on the little rod end or in the piston.
We are not talking about much but these engines can run a long time under these conditions.
Things in there are sized nicely for the long haul!
In either case, the piston is riding on the rings, of course and the skirt of the piston expands out to fill a gap left for oil support. What you hear is most likely the clacking, clapping against the cylinder wall. It's a hollow sound coming from the hollow underside of the piston.
What weight oil are you using? A thicker oil might make it quieter, just a thought? A friction modifier might help it cling longer on the parts up there while running.
The oil squirters on the later Volvo engines "deaden" that sound by coating up or flooding the under side of the pistons.
This helped compensate for the newer shorter piston height design chosen to reduce weight, for smoother and higher revolutions.
Also the extra cooling was needed because of the reduced mass.
Those Pistons got pushed even harder with inter coolers, turbo pumps and better electronic tuning.
Turbos and the Smaller cubic inch engines have to burn as much fuel (energy) to produce the same "amount of work = horsepower," as larger their counterparts, in the same amount of time!
Remember Volvo use to advertise," they could blow the doors off some V8's!"
Ha! I saw recently a V8 emblem on a newer Volvo X. What happen was "American Sales Greed!"
It's ALL about air/fuel exchange. Efficiency or longevity is debatable.
It's a long "dirty" stick when looking at it from both ends.
Today's engines are "hopped up or one race minded" in a sense, whether you believe it or not!
Just drive your engine conservatively, for the first few minutes, because it warms up faster under light loading.
Treat it like it was new expensive car and it will give you many more miles of service!
You might get ten more years out of it!
In fact, maybe more miles the "mistreated / tire burning sliders" the new cars are getting hit with today.
Beats me how they can honor warranties on these type drivers!
Maybe they don't?
Phil
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Thanks, Phil for listening to my youtube clip and giving me your advice. I appreciate your opinion that this is nothing too significant, outside of the engine aging with gracefully. Currently using a synthethic 10w-30 oil. Will switch to something a bit thicker for the next change. Do you think that maybe using a non-synthetic oil would be better?
You are spot on - the noise is more noticeable from the passenger side of the engine.
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posted by
someone claiming to be CB
on
Tue Apr 14 12:28 CST 2015 [ RELATED]
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Not to open another can-of-worms. But your "Valve Hushers" are undoubtably shot.
No need to replace them, never done it on my 1980, but happened to have the cam off on my 87 so I did them there.
Little rubber round bumpers, fit on top of the valve stems. Requires removing the Cam, and removing each of the the adjuster shims. You will find the old ones either rock hard or disintegrated and/or missing all together.
Not required, replace only if you happen to have the cam off. Engine will be fine without them. But another source for the ticking.
If the valves are adjusted to specs there should be no unusual ticking sound.
Diagram Ref part #22
http://www.volvooemparts.com/a/Volvo_1985_24023l-Fuel-Injected/_51507_5706433/Cylinder-head-B230F/GR-63504.html
http://www.volvooemparts.com/p/Volvo_1985_24023l-Fuel-Injected/Absorber/42787333/3514432.html
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I think 10/30 oil is the oil recommended most of the time for the engines.
I have not gotten all warm and fuzzy with the idea of synthetics.
Mostly because their pricing and blending marketing games!
No one puts down "in writing" the percentage of blend or the grade of that synthetics PURITY!
They have gotten a lot thicker and thinner over the years.
The engines and oil philosophy with the EPA criteria breathing heavily on their necks scares me.
Car power trains being sold with less emphasis on longevity and lies of rated power is not compared across a board of any sensibility.
I still have about 65 quarts of SAE L&M rated oil to use. The N has "NO" phosphate additive.
I am old school and like 20/50 but then I live in a more temperate climate and it gets hotter more days than not. Label me "old school with an open mind" for now!
When I was thinking about a "friction" modifier, I was relating to transmission fluids as well.
Modifiers are used to make "fluids" cling to rotating parts.
The word friction takes some thinking about. You would think friction causes heat?
I like cohesion modifier as a better word.
It's Part of the Ford specification for type F fluid.
There is also a "hint" about it being in the newer trans fluids that Volvo recommends. Trick is their "synthetics" are at $20+ a quart.
They also have concerns with brass material and "extreme pressure additives" mixing, so it's reduced or not in there at all?
That EP stuff has to stay in rear ends or gear boxes without brass synchro's.
For several years I have been using a Lucas Transmissions product in my M46 &47's manuals.
I use only a 20 percent mixture.
I control that percentage myself for less than $14+ a quart for Redline's "four" different grades? Their guarantee's are as good as mine. If you read the fine print, that's not there!
If you read closely, it comes down to the percentage of pressure additives their using. Plain old, Games!
Lucas helped one of my M46's over drives shift after hot. The one M47 that I have has 265K on it without a whimper of any problems that I have read about others having earlier.
But then I probably drive differently than some people!
I have concluded its not "all" l about the synthetics being better or the oil level but getting that oil up and around on those moving parts. Manual transmissions have no pumps!
While, with this floating in my brain of "voids," I wanting to recommend an Lucas oil stabilizer to you!
The Trouble is, my "head" juror is still debating how well, it works against piston slap. It might help oil consumption but I think it looses that edge as well, over time.
Most additives are snake oil IMHO!
Once you lose that designed and machined-in out-of-roundness clearance of the piston skirt, nothing puts it back!
The thicker oil idea, deadens the sound and might provide some cushion. That is all that can be expected.
That is about all I can say for additives or oil viscosity for engines.
Phil
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Did you make sure to tension the timing belt correctly? It could be slapping the belt covers.
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If the noise wasnt there before timing belt change most likely you are off one tooth.
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I had a B230FT that rattled like a diesel at idle, but sounded fine at higher rpm, and did not seem to burn oil. The engine had over 450,000km on it. |Eventually i blew up the engine, and got a newer post '93 engine, with piston oilers.
Have you checked your valve clearances to see if perhaps you are out of spec. Honestly your description does not sound like anything dire.
JD
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Hi all,
thanks for your help and advice. I went ahead and recorded the engine's sound. If you wouldn't mind, appreciate it if you could go to the below link and listen to my engine and let me know what you think.
Engine runs great - no loss of power or anything. I don't think I am off a tooth on the timing belt but its a possibility. Otherwise, is there an engine issue going on here, or what do you suppose the slight tapping is?
Thanks for your help in advance!
https://www.youtube.com/watch?v=-E8bP8CmZuU&feature=youtu.be
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Ha! My engine has been making that noise for a year or two now - much louder, too. I have read several threads on TB and Brickboard talking about the piston slap, and how the owner has driven the car for over 100,000 miles with the noise. It is the "graceful wear" that machine man mentioned, I think :) My solution evolved out of other systems' wear - the exhaust leak covers that piston slap sound right up!
Could also be valves out of adjustment after being pounded into their seats so many times. Wouldn't hurt (just take up a little bit of time) to pop the valve cover and check clearances.
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Also, at first cold start up it does not make this noise. Only when the engine is warmed up...
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