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1996 1.6 16v engine noise
#1
I rebuilt this engine recently and I’ve got this squeaking noise I cannot pin down. It sounds like it’s coming from the head of the engine, but it’s hard to tell. To me it sounds like camshaft speed and not crank speed. Camshaft looks a little worn but not horrible. What do you guys think? It’s quiet when cold but as it warms up the noise becomes present. I linked a video on YouTube to let y’all hear the sound.

https://youtu.be/r-97hZhBhBc
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#2
one test is drop all belts, (hot) and run for 1min, only see if noise ends belts off, (alt,AC.water pump..PS belt) only
short time. as it will overheat fast longer.
or warm it up until noise starts and drop belt.
other wise if inside engine is the noise, make sure the rocker springs are not missing. 8 of them below.


and lash set right. TDC firing each piston.

[Image: 3_18_01_19_3_28_02.jpeg]


make sure all things attached to engine not loose. even that huge air pip up top has 2 read exh,man. bolts, and more. not loose.
put pressure with hands or short 2x4 board, on to things, see if sound changes
flex the exhaust header to CAT with a board, to make sure it is not bad or the bad header flange donut not bad. and loose, (horrible pounding sound with tha bad, sounded like bad rod bearings. on mine, new engine and scared me...
keep open mind on externals. use pressure or yank thing to find any thing loose.
good luck you , on you project !!!
http://www.fixkick.com
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#3
(01-21-2019, 12:52 PM)fixkick Wrote: one test is drop all belts, (hot) and run for 1min, only see if noise ends belts off, (alt,AC.water pump..PS belt) only
short time. as it will overheat fast longer.
or warm it up until noise starts and drop belt.
other wise if inside engine is the noise, make sure the rocker springs are not missing. 8 of them below.


and lash set right. TDC firing each piston.

[Image: 3_18_01_19_3_28_02.jpeg]


make sure all things attached to engine not loose. even that huge air pip up top has 2 read exh,man. bolts, and more. not loose.
put pressure with hands or short 2x4 board, on to things, see if sound changes
flex the exhaust header to CAT with a board, to make sure it is not bad or the bad header flange donut not bad. and loose, (horrible pounding sound with tha bad, sounded like bad rod bearings. on mine, new engine and scared me...
keep open mind on externals. use pressure or yank thing to find any thing loose.
good luck you , on you project !!!

So I warmed it up and dropped all belts, the noise was still there. I even removed the camshaft and inspected the cam bearings, lobes, and rocker surfaces and all seems fine outside of some wear due to mileage. I went ahead and had the cam polished as well while it was out and even had the rocker surfaces re-arched by a machine shop I noticed when I open the oil fill while it’s running you can hear it much more pronounced so it seems to be coming from inside the engine. It sounds at the speed of the cam and not the crank. If I pull injectors one at a time the noise doesn’t change. I even pulled the pan to check rod bearings and all that. Everything seems fine. It still seems to be coming from the head. I checked the oil and cut open the filter with no bearing debris present, looked fine to me. The head was re decked and all the valve guides were replaced because they were worn when I rebuilt this engine. I’m running out of ideas outside of maybe there were some mismatched valvetrain components (since I bought this head used).

Attached is a link to the sound so you can hear it.
https://youtu.be/jMBIFMJD0ps
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#4
how do you not know that is NOT ping you are hearing. (detonation)
i guess that noise happens hot, engine cold engine and any rpm? (please tell all)
if the head was both milled and engine decked too. the total combustion chamber volume may be radially too small. (HIGH CR)
in fact a pro shop CCs them before head is put back, after all he does not know how many times that head was milled,(shaved or what ever) 55cc rings bells but IDK, forgot spec. its in the book.
Some even (wrongly) shave warped head now needing huge cuts, and then CR is way to high. and detonation.
one easy proof is compression checks show it way too high.
185 is par, seen one at 220+ due to shaving, head, (2 head gaskets can fix that)

one way to prove PING too is force engine AFR rich, and it must stop pinging or retard spark ,like turbo guys do to end the blown up engine event, under boost and AFR goes lean.
AFR (air fuel ratio)
one way more way is pull the FPR vacuum hose and plug how with golf tee, now fuel pressure goes 6 psi higher, (fuel pressure is opposite of vacuum HG inches ) this makes injectors squirt more fuel. ping ends.
and you see if ping ends if it is ping.
THE EGR (anti ping tech) is tuned off at idle or not not moving 1996+ its off parked)
so EGR is no help pinging at idle. (ON THIS CAR ONLy moving EGR goes LIVE)
if the engine is cold it should never ping, but you never told all ways it does nor does not make noise. (or I forget and is easy at my age.. eheheheheh)
http://www.fixkick.com
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#5
[quote='fixkick' pid='11172' dateline='1550444346']
how do you not know that is NOT ping you are hearing. (detonation)
i guess that noise happens hot, engine cold engine and any rpm? (please tell all)
if the head was both milled and engine decked too. the total combustion chamber volume may be radially too small. (HIGH CR)
in fact a pro shop CCs them before head is put back, after all he does not know how many times that head was milled,(shaved or what ever) 55cc rings bells but IDK, forgot spec. its in the book.
Some even (wrongly) shave warped head now needing huge cuts, and then CR is way to high. and detonation.
one easy proof is compression checks show it way too high.
185 is par, seen one at 220+ due to shaving, head, (2 head gaskets can fix that)

one way to prove PING too is force engine AFR rich, and it must stop pinging or retard spark ,like turbo guys do to end the blown up engine event, under boost and AFR goes lean.
AFR (air fuel ratio)
one way more way is pull the FPR vacuum hose and plug how with golf tee, now fuel pressure goes 6 psi higher, (fuel pressure is opposite of vacuum HG inches ) this makes injectors squirt more fuel. ping ends.
and you see if ping ends if it is ping.
THE EGR (anti ping tech) is tuned off at idle or not not moving 1996+ its off parked)
so EGR is no help pinging at idle. (ON THIS CAR ONLy moving EGR goes LIVE)
if the engine is cold it should never ping, but you never told all ways it does nor does not make noise. (or I forget and is easy at my age.. eheheheheh)
[/quote/]
The noise happens only when warmed up or near warmed up. I have an aft gauge and it’s not lean at all at idle, timing is correct. I have a lower compression ratio than stock because I’m going turbo but I have the waste gate open running no boost yet, just naturally aspirated. My compression ratio is 8.5:1 or somewhere close to that since I don’t know exact specs due to head and block decking. . My compression on all cylinders is 150psi because of the pistons. The egr is bypassed and not used at all. Noise never occurs when cold, only when warm. The noise sometimes is louder than other times but not by much. I will try messing with timing at idle to see if it quietens down some.
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#6
ok ping happens warmed up, never cold as cold is rich and rich is very cool combustion.
The ping is called more accurately Detonation as that is what it does when lean and hot and the fuel (poor grade) try high octane fuel yet?
The fuel detonates as apposed to normal and simple burning of the fuel.
It also lowers power, due to less time pushing down on the piston,
Im not saying its really lean, Im saying lean and normal from rich and cold, Im saying it can ping at STOICH mixtures, all engines can. and do if CR is wrecked.
Compression ratios.
OK step one on all good turbos is lowered CR. (base NA engine) Like done on Toyota's stock turbo' factory engines,
to that when horrible happens (boost and lean lean out) the detonation ends due to 2 things, (act 1, retards timing, act 2, the natural CR is lower than stock so the flame front cools even faster.
do the pistons have clips on pins? and are loose? some best full floating pistons use, teflon caps on ends of pins, so is safer.
I think you need and electronic sethoscope to find noise like this , its cheap.
ok 150psi I did not know that, sorry, and so is not ping, no way can it ping, unless running Coleman stove gas (lol) Naptha.

this engine has a head boss in the compubustion chamber that cause the AFR mix to pinch and move fast across that pinch point and this prevents PING on the stock engine
until a very hot day flogging it up hill with back of car with 1000 lbs or bricks and EGR goes dead it pings.
otherwise it should never ping
but 150PSI is a pussy cat, there is not enough CR to detonate, fuel,.

so try high octane
or try, moving distributor (spark time freeze jumper set) the and retard to. I'm sure its at 5deg BTDC now, and not at 20.
retard to 0 TDC firing.
if no change its not ping.
its not piston tops full of 1/4" thick carbon, its rebuilt engine,
so use this. a nice electronic stethoscope, (its just mike and amp and ear buds, i chuck the buds, and bet walmart real head phones and OMG what dream.
you can hear flea fart in dust storm. can find bad alternator bearings, bad PS pump bad water pump bad, any thing that spins, or the engine actual
[Image: steelman.jpg]
http://www.fixkick.com
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#7
I guess you have those funky retains springs in 2hd post?
the cam pulley cracked, we've see that here.
cracked valve spring, Im sure you checked all that. but it pops to my mind.
noise is bad, only the normal valve steim to lifter are normal to make very tiny tick sound .006" is tiny and not loud.
noise usually gets worse
that is why we worry it. (like call , saying fix me, fix me....)
http://www.fixkick.com
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#8
seen one 96 the
top induction pipe (huge) mount cracked and making tons of noise, huge, scary
and the loose bottom of header flange sounds like bad main bearings , 10x scary that, for sure on new engine, yikes. and simple
do not fear removing parts, or even using a 2x4" but 5 foot board and lever force the engine, left,right or even front to rear. use force, see if odd sounds end. or get worse.
just making sure its inside the engine, we do that.
Im sure this is old hat stuff that.
http://www.fixkick.com
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