|07-18-2012 11:27 PM|
|boothboy||Might be time to run a compression test.|
|07-18-2012 05:52 PM|
Pull the plug wires one at a time to see if that isolates it at all.
A lot of old Fords have broken pistons that make all sorts of strange noises.
Worn piston pins can allow the piston to hit the head which makes a lot of noise at idle.
|07-18-2012 05:45 PM|
|67MercCat||well I hooked up the vacuum gauge and boy was it hopping all over the place. I told my buddy he's gonna have to get the heads rebuilt, but he now says he rather I build him a 347 stroker....I checked all the lifters on the side its making noise but they all checked out fine as far as lift measurements|
|07-18-2012 04:21 PM|
Ford 289 lifters......
Hi,i put a crane cam and lifters in my 289 back in 1975,ran good,then started banging,i pulled the valve covers,and i rocker arm was not lifting much,i pulled the intake to check the lifters,one lifter was almost 1/8 inch shorter, dont ask,i replaced lifter and no more
|07-18-2012 01:59 PM|
|Irelands child||Try a vacuum gauge - bouncing readings will show a burned, stuck or broken valve|
|07-18-2012 12:37 PM|
|67MercCat||Well I pulled the valve cover and readjusted all the valves. the sound still persists, no broken springs and valve travel is consistent. it sounds like its coming from beneath the head, I'm banking on a bad valve or collapsed lifter. I'm about to pull the rocker arms off and push the rods down to see how much travel the have. Hydraulic lifters should be able to to give me a little play when I press the push rod down. it sounds awful.|
|07-17-2012 04:02 PM|
|boothboy||You may have a collapsed lifter or a flat cam lobe. Pull the cover and watch the amount of rocker travel. Or it may be any of the previous answers. Pull the cover.|
|07-17-2012 02:36 PM|
There are a couple different kinds of stud that Ford used - all press in. Straight ones where you can actually do a decent lifter preload adjustment, another with a stop where you just torque down. These early engines are easy to convert to screw in - pull the originals 3/8", run a 7/16-20 bottoming tap down, screw in the new studs, add roller rockers and away you go.
Later GT40/whatever version - these have pedestal mount rockers. You can either have the stud boss machined .230, the existing 5/16" threaded hole drilled out and threaded for either 3/8 or 7/16 studs - or do it the easy way with a Crane mod kit and Crane roller rockers. Also, the GT40 heads - much larger comb chambers, i.e. loss of compression ratio, round numbers 50cc for a 289, vs 60cc for a late GT40---
Now, the clank - see if one of the rocker studs has pulled out or at least one or more of the rockers has gone out of adjustment - replace the locking nut if so, but occasionally the stud strips as well. Then, it might be a broken valve spring.
|07-17-2012 02:02 PM|
@JeffB I thought that screw in studs where better that press in studs though for roller rockers (he wants to install some)? Can I have the heads milled a few thousandths to increase the compression or is that not a good idea?
@454 Rattler I pulled the valve covers this morning and it doesn't look strange at all. but looks can be deceiving. I'm going to go ahead and set the valve lash again and see what happens then. I'm guessing that these are hydraulic lifters right?
@1971BB427 I'm sorry I'm not very good at explaining sounds, it's a loud clicking but it goes away as rpms go up. It might be a valve hitting the piston, or even a worn timing gear is making the cam go out of timing a few degrees because it missing too.
|07-17-2012 11:51 AM|
|1971BB427||Can't imagine what would be described as "clanking" noise? Lifters make a clicking noise, and rods/bearings make a worse noise as rpm's go up, so probably not that.|
|07-17-2012 10:33 AM|
So pull the valve cover off and take a look. Then you would know a little more.
|07-17-2012 02:37 AM|
There is a down side!
Your 289 heads have smaller chambers than the GT40's so the GT40 heads will lower the compression ratio,also early 289 heads have stud mounted rockers which is a plus.
|07-16-2012 11:47 PM|
Well apparently the engine has not been rebuilt to my knowledge. He put an Edelbrock intake and carb but thats pretty much where it stops. I hear it coming from the drivers side for sure though. I have one of those mechanic stethoscopes to detect where the sound is coming ffrom and I can't hear it under the valve cover which makes me think it a deeper problem around the 7 and 8 piston.
It stops when the rpm rise and that kinda excludes the piston tapping thing right?
These are the original 289 heads. The guy isn't to hung on keeping it original. I was thinking about slapping some gt40's on there for him and ditch the 289 heads. My work is to get it running smooth and quiet and do some minor electrical work.
|07-16-2012 05:29 PM|
|68NovaSS||I had large roller rockers that would hit the one inch valve cover spacers on the back side on my BBC only when warm, I ground clearance behind them.|
|07-16-2012 05:20 PM|
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