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light engine knock/tick
https://slantsix.org/forum/viewtopic.php?t=52865		 Page 1 of 1
Author:  young&dumb [ Sat Jul 27, 2013 7:10 am ]
Post subject:  light engine knock/tick
hey everyone, I drive an 82 Plymouth gran fury 225 /6
recently a slight knock has developed but does not seem to be getting any worse.
it is most audible at first start but the fades quickly to barely noticeable knock/tick sound and sometimes you cant hear anything.
it seems to be down in the motor

it has 223,000 original miles
no rebuild known

if its was a main of rod bearing it would get louder under load and fast change in rpm but it doesn't seem to I can barely here it driving and idle.
it has been doin it for a few weeks now and hasn't changed so im thinkin the problem is in the head could it be a stuck lifter maybe?

any and all advice is more then welcome
Author:  robertob [ Sun Jul 28, 2013 4:26 pm ]
Post subject: 
Cracked exhaust manifold.
Author:  young&dumb [ Tue Jul 30, 2013 7:27 pm ]
Post subject: 
sorry it took so long to get back.
sound is still the same, i looked at the exhaust manifold as best i could with it still on the motor.
one place catches my attention toward the front whare it looks white around what looks like a seam the runs front to back, but i cant get a good look to see if there is actually a crack its the only place the i guess looks discolored.


the noise is loudest under heavy load. if i sit stationary and rev the engine i cant hear the noise at all in the cab or under the hood. can sometimes hear it at idle from in the car but its barely audible like you cant hear it unless you listening for it.
under load its slightly louder.
motor runs the same as before havent seen any material in the oil gonna check again at the next oil chang. (cut the filter open)
and oil presser is 45 cold 40 warm and about 20 idling warm (10w-30 pennzoil high mileage)
Author:  mattelderca [ Wed Jul 31, 2013 6:55 am ]
Post subject: 
Use a piece of hose to probe around the manifold. Put one end in your ear and use the other to listen to various parts. Like a stethoscope. White residue certainly could be near a crack.
Author:  young&dumb [ Thu Aug 01, 2013 5:53 pm ]
Post subject: 
ok so my brother and I used a piece of hose as described and no noise from the manifold so I guess its ok.
it seemed like the noise was louder toward the bottom end :shock: need to borrow a stethoscope somehow to pin point the noise.
still hasn't changed only audible at idle and under load I cant feel any vibration in sync with the noise. its just like a low thud you can here through the firewall while under load as soon as you let off its gone until you stop and idle and you can here it again

also did a compression check today and heres what I got

#1. 130 psi #4. 135
#2. 125 psi #5. 135
#3. 108 psi #6. 130

I added a little oil to #3 and it rose to 120 psi I don't know if this helps put I thought I would share the results

thanks for any input this is a daily driver and would like it stay on the road its a nice car the paint not the best but not to bad you know 31 years of door dings
Author:  young&dumb [ Fri Aug 02, 2013 8:38 am ]
Post subject: 
so good news turns it it was exhaust related but not the manifold, there has been an exhaust leak in the CAT since we got the car with it bein so noisy we decided to replace it with a piece of pipe to quiet things down so we could here the noise better.
turns out that when they were done the noise was gone like all of it now all you here in the engine bay is belts fan and accessories the not even I hint of a knock now
thank you for any inpute
now to receive the new carb and then work on the irratic mis which is minimal just annoying
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