tapping/pinging/clicking noise under load

[dawnovsky]

Hi,

I know that subject had been discussed already, but i haven't find answer clear enought to adress the problem.
I have clicking/tapping/pinging noises (sound like clicks to me, but not sure of the exact name you gave it in english) under load only.
In Neutral i can give gas and rev , there no noise.
In drive (climbing hills, passing cars, or accelerating, even moderatly) i get clicks. at constant speed, i can't really notice clicks. I assume from my understanding, and reading, it's related to advance.
For information, i m running a stock 200 (66 mustang) with DSII ingnition and module (bought new or reman from rock auto (6month ago) (for farilane 78/79)) + flametrower coil. DS2 get vaccum from manifold (connect with a T on the vac line going to the C4 trans). The coil get 8v via pink resistor wire. module get full 12 from home made modified harness.
i ve got stock motocraft spark plugs and new silicon core plugs wires.

initial advance was 12° before TDC @ 700 rpm (vaccum disconnected). Total advance (vaccum connected) at 2500 rpm was about 30°.
i ve reduce initial advance a bit down to 10° then to 9, and it still gave me clicks under load.
I haven't try to reduce advance any further as i can't hear any chance after reducing advance from 12 to 9.
I then started to think it can come from hydrolic lifter. From numerous reading lifters will be noising mainly at idle after startup.
I m running short of idea so i'll appreciate any help and your wise advices.

thanks
regards

f.

 

[FalconSedanDelivery]

disconnect the vacuum advance , then drive it ,did it stop , if it does there are 2 reasons , 1 you have it hooked to manifold vacuum , 2 , it allows too much advance too soon , you need to have the mechanical advance and vacuum advance set for your particular combo ( its called Distributor Recurving ) and again , it amounts to much more than a spring kit and a tab bend .

 

[dawnovsky]

I guess i ll try that tomorrow. well if rain stops for a while.

Well so lets assume it will stops clicking.
I have the dizzy plug on manifold vaccum. From what i ve read this is the correct way to install it . Isn't it ?
if not where else should i plug it.
lets assume now i need to have the dizzy set (vaccum and mechanical advance)
i guess if i do have clicks it means there is to much advance.
- how come it just happend under load ? dizzy can't tell the difference between dry rev on Neutral and road driving. If it can, How ?
high RPM means low vaccum on manifold, eventually dropping to 0 and accordingly gives no advance at all. Should i understand it came from centrifugal advance ?
vaccum advance can be set with a help of an adjustable vaccum actuactor (should have on of those somewhere).
mechanical advance is centrifugal, and directly eralted to RPM and resistance from the springs.

when i m crusing at 2500 rpm for instance. 2600 rmp gives clicks; at 2400 no clicks. as vacccum advance should increase a bit from 2600 down to 2400, i should get more clicks at 2400 than at 2600, right ?? as it behaving the opposite way, should i assume vaccum in not in cause ?

I guess i ll have an answer when unplugging the vaccum.
if so, centrifugal advance will have to be to by the mean of ... springs and tab bending ...

please correct me if i m wrong.

regards

 

[dawnovsky]

Hi,

I ve have a ride with vacuum disconnect and style get that clicking noise under load.
I guess it came from the mechanical advance that need to be tune so.

 

[jahearne]

Could be a small exhaust leak at the manifold.

 

[dawnovsky]

thanks. I tought about it.
There s probably an exhaust leak to. Those cast iron manifold are really are to fit properly.
DO you have a trick to make them fit nicely ? cutting gasket around each exaust may be, to prevent it from bending ?
I have replace the gasket twice lately (second time was made by the good mechanic) and i still have light dark marks caused by exhaust gaz around some of the exaust ports.

I can exaust leaks related click could be load related ?? from my understanding it should clicks even at idle and at all RPM even in neutral.
do you guys thinks my clicking could be :
-fuel pump related
-transmission related
-valves/rockers/pushrod/lifter related
-carb float level

i ve drive the car for a while today. with and without vacuum advance connected. it makes no difference on clicking. I checkthe dizzy by itself and have it fully open. the mechanical advance arm is a 13L/18L and is installed in the 13L side, witch make an average mechanical advance limit of 26°.
what ever the rpm i m cruising at, i get clicks. when crusing at constant speed, increasing gaz a little give clicks, releasing gaz a little stops clicks ...


thanks for advice ...


regards

f.

 

[Invectivus]

With an exhaust leak, it usually (for me) changed as the engine warmed up as the block and manifold warped and shifted.

I don't know if i just missed it, but when did this start, and did you make any changes around that time?

 

[MPGmustang]

for exhaust leak;

get new gasket, get 'Ulta Copper RTV'
Place RTV on gasket, use alot, both sides
this should help fix any exhaust leak, be sure to tighten bolts after 3 heat cycles, and after 1 week.

On the timing make sure your vacuum canister works, blow air in to the canister, if it can not hold air, then you need to replace the vacuum canister. (don't suck the air, fumes don't taste good)

EDIT: if you have clicks (ping) it can be too much timing or not enough timing under load. or exhaust leak

 

[dawnovsky]

hi,
I had a new inline fuel filter installed yesterday.
I had the fuel pump tested as well (according to the flow of fuel i get on my shoes, i guess it's working fine enough)
I've re-opened the duraspark to install a home made shim on the 13L arm to make it behave as a 10L. This surely producing less timing advance as the car now barely accelerate. However it did not make any difference in pinging. It might even sound worste as the engine now accelerate slower and devellop hesitation.
indeed it s surely reduce total advance of an amount probably around 6 to 8 °... and still get pinging. I will have this remove tomorrow.
I m starting to think it's exhaust related, but how can you explain relation between load and clicks ... exhaust valve can't tell the difference between load and dry rev .don't they?
from some reading it could also be caused by carboon deposit on the combustion chamber. once more how could this be load related?
from my understandment, mechanical and total advance were more likely in cause.

while the dizzy was open i ve noticed the lighter spring probably had no effect at all as it was not seating tight against supports, and heavier one seems not that heavy.
spring only determine how fast (RPM) full mechanical advance is applied, right ??

thanks

ps:
can pinging/clicking be caused by "not enough" advance ?

 

[Invectivus]

My two cents (because i'm not a mechanic)

So the difference between loaded and unloaded is throttle position at RPM. A load hangs the speed of the engine, so you can have reletivly sustained low or mid range RPM while stuffing as much air/fuel into the chamber as would at a higher RPM for that throttle position. So while you're correct, the exhaust valve doesn't really know the difference, more air/fuel means more heat and more exhaust pressure being exhausted and that can potentially be the extra oomph needed to breach the exhaust gasket.

As for carbon build up, yes, it can get hot and act like a disel Glow plug, igniting the mixture before the timed ignition event. I'm uncertain, but I would think that it would take some time for the engine to warm up for that to happen?

As for your spring, if it isn't working correctly (too light) you can get your advance too quickly, which can cause it. I'd think that, being RPM related, it would happen the same between loaded/unloaded.

 

[dawnovsky]

hi

it take me a lot a motivation this morning to decide to remove manifold completly and reinstall it with a lot of copper silicon. it takes blood and tears, removing the starter, bolts, manifold, cleaning up everything etc etc, but it surely make a big difference on the road ... no more clicks, or not enought for me to notify.
first good news about this problem since a while and for the first time i feel like going in the good direction. Plus it's really pleased my understandment of the problem.
for once i make the old guys lies as they usually said "whatever it looks like, it alway ignition related" ...

should have try this in first place, but the gasket was almost new and had been install by a garage ....


f.

 

[JackFish]

If you had an exhaust leak there would be telltale signs at that spot on the gasket you removed.
There would be a sooty spot where the gasses escaped and perhaps a dark spot on the block.
I am running without a gasket. As long as the surfaces are true I don't think it's necessary.
If Ford did it that way it must be OK. All you needed to do was retorque the bolts to spec, which is fairly low, about 30ft/lbs or so.

 

[MPGmustang]

Good to hear your ticking is muffled down

I'm always disappointed with garage mechanics, I like my outback mechanic (my cousin), someday I'll convert him that the i6 engine is worth keeping.

 

[dawnovsky]

I don't want to blame any mechanics, I m workin in an aviation hangar with lots of these guys, they are friends, give valuable advices and i they are doing great job.

the thing with "garage" is they usually don't have the time to take good care of old cars likes our. It makes much more sense for them to take 6 modern plastic cars a day for oil filter change or computer diagnostic than a single 40 y old falcon or mustang.Some ever refuse to do the job on my mustang and i have the same issue in france with my cadillac for things as common as chaging tires. When i'm doind things myself i don't mind the time i take on it, i just want the job done the right way. I m trying to do as much as possible myself, but some stuff requier garage equipements (like a lift or a press) or are just to boring or complicated to be done alone. that s why my exhaust gasket had been done, with freeze plugs and many others boring stuff in a garage.
i ve also noticed garage mechanics are less and less good at fixing or maintaining old cars. I m not a mechanic, but i ve spend time on books to understand basics and i m pretty sure i know stuff some local branded garage guys don't even know. of course there excelent at tuning 2011 BWM or VW computerized injection or things like that i have no idea about.

the thing is to locate the old guy that learn mechanics on former army jeeps or something like that, and he will tune your engine with on screwdriver and a good ear ....