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noise after cam swap please help

Discussion in 'The Hokey Ass Message Board' started by lurch423, Jul 16, 2008.

  1. lurch423
    Joined: May 2, 2008
    Posts: 100

    lurch423
    Member

    help i swapped the cam on my 64 ford witha 289 it runs fiine has good oil psi but has a knocking sound in top of the engine its loud at idle seems to go away some if you run the rpms up it sounds like its in the front of the engine but i cant pin point it with a scope it echos threw the motor pretty bad could ihave a cam bearing proublem the cam turned good and smooth when we put it in went in fine i took the fuel pump off and cranked it sound was still there i put a comp 268 cam in it new lifters chain etc checked the piston to valve clearnce all was ok like i said it runs good just got this god awfull sound im gonna take the timming cover off to make sure somthings not rubbing but if it isnt i dont know what to do any ideas how to check or were to look :confused: any help is appreciated
     
  2. Dyce
    Joined: Sep 12, 2006
    Posts: 1,980

    Dyce
    Member

    Does it miss? Pull plugs and see if something dropped in a intake port. I've seen flat cams make a clatter, and if a exhaust valve stops opening it will cause a pounding miss with the piston coming up to compress an already packed cylinder. Check the fuel pump too.
     
  3. 38plymouth
    Joined: Apr 11, 2008
    Posts: 419

    38plymouth
    Member

    Check the dizzy
     
  4. chopper99
    Joined: Jan 27, 2006
    Posts: 513

    chopper99
    Member Emeritus

    Check the harmonic balancer and pulley.
     
  5. 49ratfink
    Joined: Feb 8, 2004
    Posts: 25,070

    49ratfink
    Member
    from California

    when I had my 289 built the machine shop ***embled most of it and I put the tin and intake and other stuff on.

    I remember there was some sort of clearance issue with the new chain and gears and the timing chain cover. I can't remember what the **** it was now. must be getting oldtimers disease, I remember the shop owner telling me what I had to do because of the different chain... don't remember what that was either.

    somebody here will know what I'm talking about.
     
  6. Is it hydraulic? Are your lifters not pumped up? Seems like when you give it revs the oil PSI goes up and pumps them up?

    Good luck, what ever the case! It can get frustrating!

    Jay
     
  7. beetlejuice55
    Joined: Feb 18, 2007
    Posts: 738

    beetlejuice55
    Member

    did you put a cam ****on on the front of the cam ? to keep the cam from "walking" ?
    maybe the cam is walking in and out, and the timing gear is hitting the cover ??
    i don't know much about fords, but i used always use these cam ****ons on big block chevy's to prevent cam "walk".

    come to think of it, the cam would probbaly have to move out a long way for the gear to be hitting the timing chain cover. how much clearance does a ford have between the cover and the timing gear anyway ?
     
  8. are you running stock ratio rockers or 1.72 rockers? small block fords with stock pistons are really low on piston to valve clearance. are you running a stock fuel pump or electric? i've had the fuel pump eccentrics break before, it wont run if your using a mechanical fuel pump though. the cam cant walk forward cause fords have a plate that bolts to the block that prevents the cam from coming too far forward.
     
  9. That happened to me a long time ago.
    Mine turned out to be the cam gear bolts being just a tiny bit too long, sticking out a tiny bit and tapping on the block.
    Changing the bolts- one or two threads shorter made it go away.

    It was on a Cadillac I think.

    I have heard of mechanical fuel pumps making a similar noise if they didn't fit perfect.
     
  10. junkyardjeff
    Joined: Jul 23, 2005
    Posts: 8,703

    junkyardjeff
    Member

    I put a new timing chain set in a 60s 390 and did not realize there was a spacer inbetween the cam and gear that needed to be removed and made the fuel pump thingy hit some ribs on the inside of the cover,I an mot certain if the 289s were made the same but if it originally came with the spacer and you installed it remove it. Jeff
     
  11. Bingo!! And make sure the dowel pin in the cam is the right length. Comp sends two lengths with the new cam and I've had to modifie these for proper fit. And the easiest way to check the fit is to install the cam,cam retainer plate,top timing gear,fuel pump eccentric. Then check for clearence and that the cam will spin with no resistance>>>>.
     
  12. hotroddon
    Joined: Sep 22, 2007
    Posts: 28,240

    hotroddon
    Member

    Since you say it seems like it's in the top of the engine and it goes away with rpm, I'm going to bet it's a lifter/valve adjustment issue. Do you have adjustable rockers or the stock run em to the bottom type? If they are stock you may have to change pushrod length or go to adjustable rockers. I'd start there.
     
  13. liljgoneman
    Joined: Dec 31, 2006
    Posts: 160

    liljgoneman
    BANNED

    my first guess was too much lift in the new cam causing interference up top i.e. rocker bumping a spring retainer or some such......
     
  14. Mr T body
    Joined: Nov 2, 2005
    Posts: 2,227

    Mr T body
    Alliance Vendor
    from BHC AZ

    I hope when you replaced the cam that you also replaced the lifters at the same time. Did you break the cam in properly? How long have you run it since breaking it in? Sure hope you didn't flatten a lobe.....
     
  15. lurch423
    Joined: May 2, 2008
    Posts: 100

    lurch423
    Member

    ok thanks for the help we found it it was hitting the timming cover the early 289 had this molded in pice thats diagnal on t he cover its a sheld to keep oil off the end of the crank chain was hitting there ive changed alot of cams but this is my first 289 the first cam i wanted to use didnt have enuff clearance no valve pockets so we backed it way down this one has plenty but when we fired it up it had this god alfull knock you ever herd when we pulled it back apart you can see it was hitting bad on the end of this oil shild thingy boy was i glad easy fix justa pain in the *** i guess the double roller chain took up the clerance that the single stock chain had thanks for the help
     
  16. Hey dude be careful here. I've not seen the double roller chains make this happen. Be sure all the **** lines up right on the front of the engine. Ford had a bunch of concoxisions back in the earlier 289's,right around 64-65-66. If it aint right it will bite you and it won't be pretty. I've seen the wrong spacer/cam gear/cam retainer/fuel pump eccentric/dowel pin combination break all kinds of stuff on the front of the engine behind that timing cover>>>>.
     
  17. BigChief
    Joined: Jan 14, 2003
    Posts: 2,084

    BigChief
    Member

    Retainer to seal clearance, valve spring coil bind and rocker arm geometry and rocker to retainer clearance are also very important to check for when jumping to a new cam. More times than not you can't simply (or shouldn't) just dump a cam in a motor. The heads have to be set up correctly for the cam specs and valve spring requirements. Most times this requires machining for PC/Viton seals, adjusting spring pocket sizes/depth for the required valve spring and installed height/seat pressure....typically involving the use of non-stock retainers, keepers and/or addtional machining the of the heads.

    You may have more homework to do here........
     
  18. BigChief
    Joined: Jan 14, 2003
    Posts: 2,084

    BigChief
    Member


    Amen! There are a couple of timing sets available for these. You HAVE To make sure the right combination is there or you'll have 289 soup in a jiffy.

    -Bigchief.
     

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