Knocking sound?
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
Basically a well worn engine, tolerances get loose, noticeable especially when cold.
We're not trying to beat up on ya, just save time and aggravation. Do a good by the book compression test - remove all the spark plugs first, block throttle & choke wide open all the way, and use a fresh charged battery. Record the compression numbers for each cylinder after the same number of pumps - say 5. Each cylinder should hopefully rise quickly to a high number, and all cylinders about the same.
We're not trying to beat up on ya, just save time and aggravation. Do a good by the book compression test - remove all the spark plugs first, block throttle & choke wide open all the way, and use a fresh charged battery. Record the compression numbers for each cylinder after the same number of pumps - say 5. Each cylinder should hopefully rise quickly to a high number, and all cylinders about the same.
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Keep the plugs in order by cylinder #, between the compression test and reading spark plugs we can learn a lot about the internal condition and state of engine tune. A piece of scrap cardboard works well enough to store the plugs.
Let's say for example all the compression PSI #'s look pretty fair, except, 6 & 7 are both real low. Uh-oh. That may mean a bad head gasket. Then we look at plugs again and #6 looks almost clean compared with the others, engine coolant burning in the cylinder will do that, so it kind of confirms diagnosis.
Don't worry too much if the #s aren't super great, but we hopefully want to see them even across all cylinders. Compression will often improve as we get things tuned up. Rings will get sticky over time and usually respond to some heat cycles and maybe some Rislone or Marvel oil. But if there's a bum cylinder with a broken ring or burned valve no chemicals are going to help. That's why we want to check this first before getting too deep into a tuneup and buying parts or spending time on it.
Let's say for example all the compression PSI #'s look pretty fair, except, 6 & 7 are both real low. Uh-oh. That may mean a bad head gasket. Then we look at plugs again and #6 looks almost clean compared with the others, engine coolant burning in the cylinder will do that, so it kind of confirms diagnosis.
Don't worry too much if the #s aren't super great, but we hopefully want to see them even across all cylinders. Compression will often improve as we get things tuned up. Rings will get sticky over time and usually respond to some heat cycles and maybe some Rislone or Marvel oil. But if there's a bum cylinder with a broken ring or burned valve no chemicals are going to help. That's why we want to check this first before getting too deep into a tuneup and buying parts or spending time on it.
Lead Driver
Joined: Aug 2003
Posts: 6,305
Likes: 18
From: Boulder Creek, Ca
As already noted by member's, found it helpful to narrow source, I have since purchased a stethoscope but in the past used a hose to pin point a problem, in my case took a nano second to determine a lifter was sticking in a specific cylinder. Took a compression test as described by TA455HO to confirm. Pulled the lifter and found it was 1 step removed from collapsing. Purchased a cam and lifter kit, now all is well.
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
idk...the tip looks nice and brown...
anyway, odd question, could a worn water pump cause a knocking type sound? I was checking the belt and for some reason grabbed the fan and it moves back and forth roughly a 1/16 of an inch or so (laterally). And when I jiggle it it sounds like it could be making the same sound as the knocking I'm hearing. I suppose I could just remove the belt and run it for a sec to see if it stops making noise couldn't I?
anyway, odd question, could a worn water pump cause a knocking type sound? I was checking the belt and for some reason grabbed the fan and it moves back and forth roughly a 1/16 of an inch or so (laterally). And when I jiggle it it sounds like it could be making the same sound as the knocking I'm hearing. I suppose I could just remove the belt and run it for a sec to see if it stops making noise couldn't I?
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
really not necessary comments tbh. If you can't put in somewhat thoughtful advise please don't comment on my post then. Thanks
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
I'm sorry, I take things literally most of the time. And I just don't like when an experienced person is making jokes to someone just starting out in this hobby.
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Well OK, I really didn't mean to offend anybody by that. Running it without the belt for a few is a good troubleshooting test, that's all I was saying! There really shouldn't be hardly any sideplay if that's the problem you'll find out quickly.
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
well hey it's not a big deal. And I noticed you live in waterloo? You're like 10 minutes away from me lol. I'll try pulling off the belt tomorrow quick, then do compression test
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
Well did compression test. Not too good. 90 in cylinder 1, then 75 in 2-4, then 90 in 5-8. I adjusted the carb to run a little leaner at idle and now it makes this odd backfiring noise. Seems like it's coming from the drivers side. Sometimes it almost sounds like a screwdriver tapping the valve cover. Also, is the driver side valve cover correct? They seem to be mismatched. I'm not sure.
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
Ok, so not real good, but we know what we're looking at with real numbers now instead of guessing. One thing to narrow it down is squirt maybe a teaspoon or so of engine oil in the spark plug hole and try again. If the compression in that cylinder jumps, then the rings are worn. No change, look at valve issues.
How fast a cylinder pumps up is diagnostic too. Ideally it reaches 90% of the high # on the first pump or two. Now, one thing to keep in mind an engine way out of tune, and has sat for a long time, the compression is apt to be low. Rings and valvetrain parts are gummed up and sticky. If you can get everything above 110 say it might be a nice runner for just zookin' around in. Kinda depends on your goals and budgeting. Maybe drive this for a while and keep an eye on a short block for rebuild. But it's possible with some oil changes & Marvel oil or Rislone, ATF, etc, and get it through a few heat cycles - good and hot, it will unstick rings and compression come back up. Maybe, or good enough for your purposes.
How fast a cylinder pumps up is diagnostic too. Ideally it reaches 90% of the high # on the first pump or two. Now, one thing to keep in mind an engine way out of tune, and has sat for a long time, the compression is apt to be low. Rings and valvetrain parts are gummed up and sticky. If you can get everything above 110 say it might be a nice runner for just zookin' around in. Kinda depends on your goals and budgeting. Maybe drive this for a while and keep an eye on a short block for rebuild. But it's possible with some oil changes & Marvel oil or Rislone, ATF, etc, and get it through a few heat cycles - good and hot, it will unstick rings and compression come back up. Maybe, or good enough for your purposes.
Thread Starter
|
Tuned
Joined: Dec 2017
Posts: 387
Likes: 22
Ok, so not real good, but we know what we're looking at with real numbers now instead of guessing. One thing to narrow it down is squirt maybe a teaspoon or so of engine oil in the spark plug hole and try again. If the compression in that cylinder jumps, then the rings are worn. No change, look at valve issues.
How fast a cylinder pumps up is diagnostic too. Ideally it reaches 90% of the high # on the first pump or two. Now, one thing to keep in mind an engine way out of tune, and has sat for a long time, the compression is apt to be low. Rings and valvetrain parts are gummed up and sticky. If you can get everything above 110 say it might be a nice runner for just zookin' around in. Kinda depends on your goals and budgeting. Maybe drive this for a while and keep an eye on a short block for rebuild. But it's possible with some oil changes & Marvel oil or Rislone, ATF, etc, and get it through a few heat cycles - good and hot, it will unstick rings and compression come back up. Maybe, or good enough for your purposes.
How fast a cylinder pumps up is diagnostic too. Ideally it reaches 90% of the high # on the first pump or two. Now, one thing to keep in mind an engine way out of tune, and has sat for a long time, the compression is apt to be low. Rings and valvetrain parts are gummed up and sticky. If you can get everything above 110 say it might be a nice runner for just zookin' around in. Kinda depends on your goals and budgeting. Maybe drive this for a while and keep an eye on a short block for rebuild. But it's possible with some oil changes & Marvel oil or Rislone, ATF, etc, and get it through a few heat cycles - good and hot, it will unstick rings and compression come back up. Maybe, or good enough for your purposes.