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engine knock

changed my oil after my ho conversion finally after 3-400 miles, now i got a slight engine knock on first start up, but after a couple minutes it goes away.
sticky lifter(s) maybe? running 10w30 oil
  i don't think it could be bearings, they were replaced about a year ago plus you would think the knock would get worse after it got warmed up. she runs great with no complaints.

Thanks for any responses
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

engine knock

Reply #1 –
is it a knock or a tap? lifters are usually more of a tap, did you replace them during the conversion? sometimes if thier just clogged up a little, you can ad a quart of ATF to the oil, run it five or so minutes and change it with a lil thicker oil(10w30 if you prefer). i know that kinda sucks for you seein's how you JUST changed it. i'd wait to hear any other possible suggestions first
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

engine knock

Reply #2 –
My car did that when it had a brand X oil filter. Motorcraft filter fixed the problem.

engine knock

Reply #3 –
grutinator- kinda in between a knock and a tap, i used the original lifters that were in before the cam change.

soft touch- i will try the filter and see if that helps
thanks
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

engine knock

Reply #4 –
If you started the car only once since the oil change and heard the noise, it's nothing to be concerned about.

If you have started the car several times and it knocks a little on start up each time, then I would do as softtouch advised. Either Motorcraft or some other good filter such as WIX, Purolator PureOne, etc. Stay away from Fram. You may also have to go to a thicker oil. I always run 20W50.

engine knock

Reply #5 –
she's been started,ran and driven 5-6 times since the oil change and after a few minutes the noise is gone. i had put 20w50 in first and i had the noise and after a little reading on some forums alot of the stang guys are running the 10w30 so i drained and put some of that in and still the little tap/knock, and yes i am using the fram filter so i think i am going to change that as soon as i get home.
  if the filter fixes it then i am going back to 20w50 the next change
Thanks again guys
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

engine knock

Reply #6 –
well i changed the filter to a wix, no luck
any other suggestions? i know it's hard to diagnose something without being there but this start up noise bothers me. car sounds fine after a few minutes and runs fine with no other complaints except as always you still want more power,, ha! ha!

thanks again guys
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

engine knock

Reply #7 –
Sometime agao,I had what I thought was knock in the engine,and I got that sinking feeling of Doom.It turned out to be the smog pump knocking.Smog delete now,no knocking.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

engine knock

Reply #8 –
ATF fluid has a 30 weight to it so don’t be afraid to put it in as long as you mix it w/at least 2-3 quarts of motor oil to stop the foaming. ATF fluid is simpler to marvels mystery oil it has a high detergent to clean and free your lifters. This is if this is your problem.
Stay away from 20w50 oil was your motor built for it probably no. I don’t care what others say you stated you put bearings in the car so I assuming you rebuilt it- who did you machine work ask them what oil you should run I’m sure he will tell you 30 weight and no more then 40 weight.

engine knock

Reply #9 –
Some 5.0's are known to knock when cold till the pistons expand.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

engine knock

Reply #10 –
Quote from: 5.0willgo;188897
I always run 20W50.


:eek:
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

engine knock

Reply #11 –
If you use oil that is too heavy it will go through the filter bypass valve instead of the filter.
At least until it gets hot and thins out.

engine knock

Reply #12 –
sounds like it could be your bearings to me....

engine knock

Reply #13 –
Quote from: vinnietbird;189308
Sometime agao,I had what I thought was knock in the engine,and I got that sinking feeling of Doom.It turned out to be the smog pump knocking.Smog delete now,no knocking.


gots a new smog pump on it
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

engine knock

Reply #14 –
Quote from: flipnbird;189426
gots a new smog pump on it


Quote from: 1WLD BRD;189421
sounds like it could be your bearings to me....


if it was my bearings would't it get worse as the oil thins when warm?
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )