Community Forums

whiterhino11 · 08-17-2010, 05:30 PM

Hello Folks,
I'm back and so is the engine noise.. It seems too had disappeared for a short period of time but now it’s back and more frequent. I have continued to use injector cleaners along with a high octane gas but it doesn't seem to make a differences. I took a few minutes and removed my serpentine belt so that I could get a true feel of each pulley thinking that it might be coming from one of them but they all seem tight with the exception of the water pump. This seems to have some play in it but I not sure if that's normal? And looks like a real bear to replace.

Your thoughts please.

1999 Fleetwood Bounder 32H, V10

Lt46 · 08-17-2010, 06:07 PM

Well, if it were mine, I'd take the engine cover off and go for a ride uphill with a mechanic onboard. You'll have to try and locate where the sound is coming from somehow. This would be my 1st attempt at doing that. That is unless you have other engine performance issues that might steer someone into a certain direction. Good luck.

whiterhino11 · 08-17-2010, 06:28 PM

The engine runs great and I have no other issues. It seems to have enough power to climb any hill and I don’t hear any other noises other then the bucket of marbles. I replaced all of the spark plugs to a stainless steel and I looked at each one after removing them and they seemed fine, my son and took a ride up the highway and did just that. I lifted the engine hood and tried myself to locate where the noise was coming from but with all the roar of the engine it made to difficult to identify.

Gary - K7GLD · 08-18-2010, 05:59 PM

Perhaps bad bearings in one of the external engine devices - alternator, AC compressor - or fan/idler? And then, there's the universal joints or center driveshaft support bearings...

whiterhino11 · 08-18-2010, 06:13 PM

I'm going with bad bearing within the water pump.. Once I removed the belt so that I could put my hand around all the pulleys, I found that the water pump is loose and make a noise when I pick up on the fan blade. I've looked at what it's going to take to change it and it doesn't appear to be an easy job..but I really think it could be coming from there?

Gary - K7GLD · 08-18-2010, 10:28 PM

Quote:

Originally Posted by whiterhino11

I'm going with bad bearing within the water pump.. Once I removed the belt so that I could put my hand around all the pulleys, I found that the water pump is loose and make a noise when I pick up on the fan blade. I've looked at what it's going to take to change it and it doesn't appear to be an easy job..but I really think it could be coming from there?

YUP - sounds like you found the problem!

PlayItForwrd · 08-18-2010, 10:38 PM

(*edit* just read the water pump theory, hopefully that's the problem---but I'm leaving this below anyway, as I've experienced this problem before....)

Working on the assumption that your noise IS engine knock...

I'm not absolutely certain, but 99% or so--- that your engine is run by computer, and your engine has a knock sensor to detect 'the marbles'-- when it does, it tells your computer, and your computer will start backing off the ignition timing to reduce or eliminate the knock. Most modern engines are rather efficient at eliminating knock, even when using the crappiest gas. Since yours is sounding like marbles, I am of the opinion that your timing isn't backing off whatsoever. This is an indication that your knock sensor is bad, or disconnected. Most everything else in the knock-detect circuit, if bad, would likely throw a "service engine soon" trouble code. However, the knock sensors that I'm aware of are usually in a passive state, and the computer has no idea if it's working or not.

If your engine IS knocking as bad as you say it is (by the sound you describe), you're doing it no good-- You should explain to a mechanic what's going on, and request a test drive with an engine analyzer connected, to determine if the ignition timing is doing what it should be...

speed racer · 08-19-2010, 09:18 AM

Did you start the engine with the belt off to see if it still made the noise? If the knock sensor is working it should take care of any low octane gas noise. You can check this by tapping on the side of thr block while checking the timing. Tapping on the block should retard the timming.

whiterhino11 · 08-20-2010, 04:30 AM

I didn't start the engine while the belt was off but I put it back on last night so that I could take a 20 miles ride up the road to dump my tanks and I never heard a sound from the engine??? The only thing I've done to it in the last couple of days was remove the belt so that I could take to my local auto parts store and match it up to have a spare then I checked the pulleys while it was off also, This is when I found the loose water pump..I looked around the engine for the knock sensor but I'm not sure if I've located it but I found a sensor located bottom driver side front which I check to make sure that it was plugged and pulled on the wires a little just to be sure they weren't broken. we are heading back out tonight for a short 3 hour drive to do some camping, I'll see if it comes back again but in the meanwhile I've ordered a water pump which I tend to replace next week.

Thanks everyone for all your help!

txdutt · 08-20-2010, 05:14 PM

buy a couple of cans of Seafoam & put into your gas on the next fill up, will help clean out your fuel injectors--check your air filter out & change it if it's dirty, may also want to change the fuel filter (if it's changeable, no idea about a Ford chassis) cheap preventative maintenance IMO....

Gary - K7GLD · 08-20-2010, 06:01 PM

Quote:

Originally Posted by whiterhino11

I didn't start the engine while the belt was off but I put it back on last night so that I could take a 20 miles ride up the road to dump my tanks and I never heard a sound from the engine??? The only thing I've done to it in the last couple of days was remove the belt so that I could take to my local auto parts store and match it up to have a spare then I checked the pulleys while it was off also, This is when I found the loose water pump..I looked around the engine for the knock sensor but I'm not sure if I've located it but I found a sensor located bottom driver side front which I check to make sure that it was plugged and pulled on the wires a little just to be sure they weren't broken. we are heading back out tonight for a short 3 hour drive to do some camping, I'll see if it comes back again but in the meanwhile I've ordered a water pump which I tend to replace next week.

Thanks everyone for all your help!

YUP -regardless of whether or not the loose water pump is the source of your noise, you had better get it swapped out ASAP! Otherwise, you can count on it completely failing at the worse time and place - lots better to fix it at YOUR time/place of choice than Murphy's!

whiterhino11 · 08-30-2010, 08:28 PM

Hello everyone,

I've replaced the water pump last week in hopes it would correct the problem but no such luck!! Can anyone tell me the location of the knock sensor? It seems that the noise is most prominent when the motor is turning at 2700 RPM and it doesn't matter whether I'm climbing a hill or cruising the flats and even going down hill it really loud at 2700 RPM??

Thanks again..
Bob & Donna

DAN L · 08-30-2010, 10:50 PM

Quote:

Originally Posted by whiterhino11

Hello everyone,

I've replaced the water pump last week in hopes it would correct the problem but no such luck!! Can anyone tell me the location of the knock sensor? It seems that the noise is most prominent when the motor is turning at 2700 RPM and it doesn't matter whether I'm climbing a hill or cruising the flats and even going down hill it really loud at 2700 RPM??

Thanks again..
Bob & Donna

I don't know where the knock sensor is on your engine.

check this out for some ideas of where to look for the noise and how to possibly fix it.

I have a 99 f-350 v10 gas engine. It is knocking... - JustAnswer

whiterhino11 · 08-31-2010, 06:02 AM

Hello Dan,

I don't believe that my noise is coming from the bottom end, it seem to be located in the top front and the only time you'll hear it is when the RPM hits 2700.. I'm not sure why but it will do it every time no matter what speed but only after the engine has warmed up..

1999 Bounder v10 6.8.

Thanks