Can you identify this bad engine noise?

[66horse]

My new rebuilt engine is making a bad noise.<br><br>It did not make this noise at first. Drove it about 5 miles and then next time I Started the bronco the noise was there.<br><br>Sound files of it here:<br>66Horse bad engine noises<br><br>As always any help is greatly appreciated! This is the 3rd enigne in a year. Doh!

 

[Jeepster]

something is lose.

 

[66horse]

Any idea on what might be lose? I am pretty sure that it is not the rockers. When I pull the valve covers, the noise does not get louder. It actually gets harder to hear.<br><br>I know it is a bad recording but you can really here the bad noise. Other than that the engine sounds good.

 

[Krusher]

This must be a test. It sounds exactly like a Caterpillar 3208 diesel.

 

[66horse]

[quote author=Krusher link=board=5;threadid=12788;start=0#95931 date=1041363930]<br>This must be a test. It sounds exactly like a Caterpillar 3208 diesel.<br>[/quote]<br><br>Unfortunately it is a Ford 289. :-U :-[

 

[Jeepster]

I do notice the "ticking"(?) goes away if you rev it a little. Exhaust leak?

 

[CG]

[quote author=jeepster link=board=5;threadid=12788;start=0#95936 date=1041364114]<br>I do notice the "ticking"(?) goes away if you rev it a little. Exaust leak?<br>[/quote]<br><br>Funny you say that...mine is having this very problem.

 

[Jeepster]

look around the manifold? just a guess. might need to retorqe.

 

[66horse]

[quote author=jeepster link=board=5;threadid=12788;start=0#95936 date=1041364114]
I do notice the "ticking"(?) goes away if you rev it a little. Exaust leak?
[/quote]

I don't think it is an exhaust leak. It seems to be too loud for that. But on the rev thing that is true. Well when you rev it, the sound is there and quickens but gets drowned out more by the engien noise. when you let off, it actually goes away for about a second and then starts again.


Adn congrats on 3000 there Jeepster

 

[BwoncoHowie]

It's tough to say by the recording unless you can pinpoint the area where the noise is coming from. I have experienced similar noises. Here are a few...<br><br>1) Mechanical fuel pump going bad.<br>2) Piston skirt slap.<br>3) Wrist pin loose in piston.<br>4) SPS rod bolts hitting a Boss 302 windage tray<br><br>I hope it's #1

 

[Krusher]

[quote author=66horse link=board=5;threadid=12788;start=0#95943 date=1041364433]<br>[quote author=jeepster link=board=5;threadid=12788;start=0#95936 date=1041364114]<br>I do notice the "ticking"(?) goes away if you rev it a little. Exaust leak?<br>[/quote]<br><br>Well when you rev it, the sound is there and quickens but gets drowned out more by the engien noise. when you let off, it actually goes away for about a second and then starts again. <br><br><br>The more I listen to this, the more I'm conviced it's a lower end problem. Possible spun rod bearing.<br>[/quote]

 

[76Broncofromhell]

Hows the oil pressure look? If you are in the lower than 30 at idle I would be wary of a rod bearing. Could be a lifter tick, bad fuel pump, or if you have roller rockers it could be the arm taping the the splash shield on the valve covers.

 

[66horse]

DOH!<br><br>Ok it has an electric fuel pump so cant be that. Oil pressure is about 50 at idle.<br><br>It seems a little loud to be a lifter tick to me, but I am not really experienced at engine diagnosis so not sure.<br><br>It is hard to tell where the noise is coming from but it does seem to be coming from down in the depths.<br><br>So if it is a rod bearing how do I tell this. Cant if be diagnosed without pulling the engine? What I am looking for and how do I tell?<br><br>Thanks for your helps guys and any other opinions will also be gladly listened to.

 

[BwoncoHowie]

Now would be a nice time to have a magnetic drain plug, like was discussed on this site a week or so ago.

 

[Explore74]

If you want to check for a rod bearing try this:<br>*pull the plugs out.<br>*get a wooden dowel rod about 18"long(1/4" will work)<br>*rotate engine till a cylinder is 1/2 way up/down bore<br>*put dowel rod in that plug hole and push down on piston slightly(don't break rod)<br>*now with a wrench, rock engine back and forth a few degrees.<br>*repeat for all 8 cylinders.<br>This is time consuming, but if a rod bearing is spun, you should feel crankshaft movement with the wrench, but on the dowel, you will feel little movement and you should feel the crank contacting the upper or lower half of the big end of the rod. This is no garauntee, but usually when you spin one, it "eggs" the big end and you will be able to detect this clearance. Good luck.

 

[Krusher]

First thing I'd do is drain the oil. If you have a bad bearing, you'll see some metal/copper looking stuff floating in the oil. Although with only 5 miles on it, it may not have worn enough to see a trace, but could have. With the oil drained out, pull the pan off. I notice you have a 2 1/2 suspension lift, so with a jack lifting up the frame, not the axle, you should get enough clearance to clear the front diff with the oil pan. once off, you got a clear view of the crank and the rods.

 

[Explore74]

krusher makes a good point. You could manipulate all the rods and easily see if it is a problem with a rod/journal.

 

[66horse]

Alright, gonna go pull the pan right now. So once i get it off, am I just trying to find some play there, Visually see the problem?<br><br><br>Thanks again guys!<br><br>Steve

 

[Explore74]

[quote author=66horse link=board=5;threadid=12788;start=15#96021 date=1041370079]<br>Alright, gonna go pull the pan right now. So once i get it off, am I just trying to find some play there, Visually see the problem?<br><br><br>Thanks again guys!<br><br>Steve<br>[/quote]<br>You will get a TINY bit of movement normally. But, if you can rock the big ends back and forth or up and down, there is a problem. If you are pulling the pan anyway, I would pull the caps off one at a time and check out the bearings. If you pull a cap, and the two bearing halves are rolled one on top of the other, this is a spun bearing, and the fun begins.

 

[Krusher]

[quote author=66horse link=board=5;threadid=12788;start=15#96021 date=1041370079]
Alright, gonna go pull the pan right now. So once i get it off, am I just trying to find some play there, Visually see the problem?


Thanks again guys!

Steve
[/quote]

Once the pans off, and you got a clear view of the internals, have someone put a wrench and socket on the crank bolt, and turn the crank back and forth only enough to "rock the crank". This is easier to do with the plugs out and no compression in the cylinders. You should not only be able to hear a knocking sounding of the rod contacting the crank if it's a bad rod bearing, you should be able to see it rock.