Another Set Back (very Frustrated)

-
DARTLARRY

DARTLARRY

Well-Known Member
Joined
Mar 19, 2007
Messages
578
Reaction score
242
Location
FORT WAYNE IN
I Have Been Working On My Car Since Last January. Everything Has Been Fine Until I Fired Up The Motor Last Week (360). At Idle It Runs Great, Once Over 2 Thousand Rpm It Starts To Have A Loud Knock. The Motor Is Stock Except For Cam, It Only Has 60 Thousand Miles On It, The Bottom End Seems Fine (but Who Knows). Im Going To Drop The Pan And Check The Bearings Today. Im Out Of Time And Money. Its Hard To Raise Four Kids And A Dart. On Minimal Income. If Anyone Has Any Suggestions, Or Knows Where To Get A Rebuild Kit Or Pistons For Cheap. It Would Really Be Appreciated I Need Advice And Probably Parts For Cheap. Thanks In Advance.
 
Can you clarify if the motro was all ready running well (with the new cam) before you recently refired it or was the cam added during its hibernation? Before you go out looking for/buying parts, let's diagnose this thing.
 
The Cam Was Added This Spring, The Second It Ate In Two Years. Could It Possibly Be Cam Bearings, How Do You Check To See If Its Getting Oil Through The Gallerys
 
So, are you saying that the motor was fine until the cam was installed? If so it would seem logical that the noise has something to do with cam install. Did you change lifters, springs, chain and gears? Could camlift be high enough that valve is hitting piston, retaining hitting valve perch, etc.? Is cam installed properly? Was crank banged around removing or replacing balancer? Is distributor in properly? I would go back and check everything done doing installation to find problem. JMO, Mike
 
If it has a rod knock usually you can hear it at idle.

Is the knock there at with you just rev'ing it? Or does it have to be under load? A faster knock is at the crank side, slower at the cam I think, I could be wrong though.

Hopefully it's just a pushrod or rocker arm.
 
New Cam And Lifters, New Chain And Gear. Pulled Valve Covers No Broken Springs Valves Move Fine Not Stuck Or Broke. Noise Is Internal Not Up Front. I May Have To Pull Intake Manifold And Check Cam And Lifters
 
Check to see if your pushrods hit the guide holes in the heads maybe? You'll see a ring on the pushrod where it's making contact.
 
put a timing light on it and run it at 2000rpm. if it is in time with the light, its most likely in the topend. if it is at double the time of the light, it is most likely in the bottom end.
 
Piston hitting the valves? sounds like you might not have enough clearance with the new cam?
 
The Cam Is Supposed To Be Mild, It Is A Purple Shaft. I Bought It Used 455 Lift Should Be Fine. How Do You Measure It. If Its Bigger I Know A Guy That Will Not Like Me.( Actually My Fault For Buying Used Cam)
 
You should step back here a little, Tell us what happened to the first cam? Wipe out a lobe or did the bearing surface go out?
If the rocker arms are getting oil, than at least two cam bearings are getting oil.
To answer your question about the cam bushings, the engine would have to be apart, you can run a rod thru the hole on the main bearing up to the cam bearing or just use a flashlight and make sure there is light from the mains to the cam bushings.
You could cut the oil filter open and see if there are any metal filings in the filter media.
If you had a pushrod or rocker arm problem it should be missing all the time.
 
check the convertor bolts if you had the motor out,or see if the flexplate isn't cracked (happened to me 2 times)
 
smooth at an idle but ruff at 2000 rpm kinda of confusing what kind of noise and does it smooth out back at an idle after reving it up also what did this car originally come with a 6 or an 8
 
DARTLARRY said:
The Cam Is Supposed To Be Mild, It Is A Purple Shaft. I Bought It Used 455 Lift Should Be Fine. How Do You Measure It. If Its Bigger I Know A Guy That Will Not Like Me.( Actually My Fault For Buying Used Cam)
Click to expand...

Measure the base circle and subtract this from top of lobe measurement and multiply by 1.5
 
the first cam lost a lobe, i have only run the car a few minutes with the new cam the noise started right away. i ran a compression check on all cylinders 140 max and 120 min. so they seem to be holding compression. i filled each cylinder with 100 psi and never leaked down. so valves are good and rings are good. the noise is sharp and right in your face. its not hollow. i put stethoscope on oil pan, you could hear it, but it was not as loud as you would think it should have been. i will pull the timing cover, and intake manifold this week to look at the cam and lifters
 
HERES AN UPDATE, PULLED INTAKE, CAM AND PUSHRODS LOOKED GOOD, OUT OF COURIOSITY I PULLED ONE HEAD, EVERYTHING LOOKED REALLY GOOD, UNTIL I APPLIED PRESSURE TO THE NUMBER EIGHT PISTON. THE THING MOVED 3/16 OF AN INCH. IS IT SUPPOSED TO MOVE THAT MUCH? THE OTHERS DONT MOVE AT ALL. COULD POSSIBLY BE A BEARING OR WRIST PIN I THINK THIS IS WHERE THE NOISE IS COMING FROM. I WILL PULL THE PAN LATER TO CHECK THE BEARING. MY QUESTION IS IF THE BEARING IS GOOD CAN I JUST CHANGE THE WRIST PIN? or should i do a complete rebuild. this is an original low mile motor THAT IS VERY CLEAN. THE CYLINDER WALLS HAVE NO RIDGE AND THEY ARE SMOOTH AS YOU CAN GET. MAY NOT NEED MACHINING. BUT IM WORRIED THAT LACK OF OIL MAY HAVE CAUSED THE PROBLEM. CAN SOMEONE PLEASE POINT ME IN THE RIGHT DIRECTION. I DONT MIND DOING THE WORK. BUT I ONLY WANT TO DO ONE TIME.
THANKS
 
DARTLARRY said:
HERES AN UPDATE, PULLED INTAKE, CAM AND PUSHRODS LOOKED GOOD, OUT OF COURIOSITY I PULLED ONE HEAD, EVERYTHING LOOKED REALLY GOOD, UNTIL I APPLIED PRESSURE TO THE NUMBER EIGHT PISTON. THE THING MOVED 3/16 OF AN INCH. IS IT SUPPOSED TO MOVE THAT MUCH? THE OTHERS DONT MOVE AT ALL. COULD POSSIBLY BE A BEARING OR WRIST PIN I THINK THIS IS WHERE THE NOISE IS COMING FROM. I WILL PULL THE PAN LATER TO CHECK THE BEARING. MY QUESTION IS IF THE BEARING IS GOOD CAN I JUST CHANGE THE WRIST PIN? or should i do a complete rebuild. this is an original low mile motor THAT IS VERY CLEAN. THE CYLINDER WALLS HAVE NO RIDGE AND THEY ARE SMOOTH AS YOU CAN GET. MAY NOT NEED MACHINING. BUT IM WORRIED THAT LACK OF OIL MAY HAVE CAUSED THE PROBLEM. CAN SOMEONE PLEASE POINT ME IN THE RIGHT DIRECTION. I DONT MIND DOING THE WORK. BUT I ONLY WANT TO DO ONE TIME.
THANKS
Click to expand...

Did the engine have good oil pressure all the while? If it did you would think the rod bearing would be okay and the problem would be in the wrist pin area. If it is something in the area of the wrist pin, with 3/16" movement you may need a piston because something is going to be seriously worn out/broken. I look forward to hearing what you find.
 
You must log in or register to reply here.
-

Back
Top