View Full Version : Help! Truck sounds like a helocopter!!

05-22-2009, 11:25 AM
I need to fix this thing fast, I am leaving on vacation for a month and the guy taking my lawns needs to use my truck while I am gone!

All started last night when I started it up and it was vibrating real bad after startup (the engine was probably pitching 2" or so!) Then it started sounding like a really bad exhaust leak or something is rubbing everytime it goes around. (but not metal..???) Even when cranking it make the noise really loud like a fan blades catching a lot of air. I do notice that it still starts up the same so i really dont think its something wrong with the engine like was my first thought (broken valve spring or a cylinder not firing or something) My next step is to remove the cover between the engine and tranny and see if something wrong with the fly wheel or something. I have checked everything over visibly from the outside so I am NOT just asking before I pop the hood... Anyone have any idea, its my first diesel and my first Auto tranny.

Last night it seamed to drive ok too maybe a little low on power though.

05-22-2009, 12:20 PM
no help on the truck, but taking a vacation this early in the growing season...must be nice...:)

have you tried taking the fan off of the truck(if its engine driven) and see if that helps. an out of balance fan can make the engine act/sound funny, but there should not be a loss of power...

Problem with the Turbo??? maybe an air leak between the turbo and intake manifold...???just tossing stuff out there...

05-22-2009, 12:47 PM
Its an N/A diesel, A fan can actually cause that much noise and vibration??

05-22-2009, 12:47 PM
I will try taking off the belts and see, it even does it while It is cranking so I will know immediatly.

05-22-2009, 01:13 PM
That didnt fix it.

05-22-2009, 01:29 PM
put a 1/2 of one blade on on your mower and engage the blades :)...a severely out of balance fan can create the illusion of much larger problems..

05-22-2009, 02:36 PM
I called 2 diesel mechanics, one said he never heard of a truck sounding like that, the second said 6.9's are notorious for throwing rocker arms or having the studs pop out of the head. I removed the drivers side valve cover and nothing is wrong so I am working on the pass side. Gonna take a while. Hope it didnt jack up the head... it would literally total the truck.

05-22-2009, 03:38 PM
My next step is to remove the cover between the engine and tranny and see if something wrong with the fly wheel or something.
What you're hearing may be roll-over noise from the tranny due to the vibrating engine.

Why exactly it vibrates I'm not sure. Miss fire due to leaky injectors or some sort of imbalance, i.e. faulty dual mass flywheel (if equipped) or problems with the transmission itself.

Just start it up again, watch and increase the revs slowly. See if the vibration has a rev sweet spot or just indifferent.

lawnboy dan
05-22-2009, 09:33 PM
your first mistake is taking a vacation this time of year.second is not having a backup truck

05-22-2009, 10:19 PM
Your right, but I am just a part timer and I got them covered while I am gone. I dont have anything back up... can't really afford it.

I got the truck towed to a mechanic tonight. Should find out tommorrow or Monday. This sucks.

05-26-2009, 09:41 PM
So what is wrong with it?

05-29-2009, 12:28 PM
Well I just got the news, its either a couple of burnt intake valves or some carbon buildup on some intake valves, causing them to not close all the way but the noise I was hearing was compression coming up thru the intake. I am just gonna wait till I get home and fix it myself as it was a minimum of a grand to have the guy fix it... plus parts

05-29-2009, 06:35 PM
Humm - sorry about this first off. Secondly, I wouldn't have suspected valves, that's a little unusual. I would have suspected a bad injector or two. This can cause a pretty unbalanced engine and (obviously) quite a miss as well.

Check out www.thedieselstop.com There's quite a few very knowledgable Ford diesel folks on there, and that old 6.9 idi, while not the strongest as far as it's reputation, is still a solid old engine. Don't worry - once it's back up to speed it'll take you a long ways. Good luck and enjoy your vacation!

05-30-2009, 12:28 AM
Ya but the noise made total sense when you hear it.

06-25-2009, 11:28 PM
In case anyone was still wondering I did find the actual problem to be a bad head gasket between the middle cylinders on the pass side.

It has taken me about 16 hours to get the heads off (the first 7 getting the engine tore apart enough get the drivers side head off) and the last 9 taking the air conditioning, injector pump, valley pan, and pass side head off today. One of the bolts was so filled up with junk that I had to use a breaker bar and cheater and spent 3 hours turning it, just to later find out it was already out of the head (when its that tight, you think its still in the block..???)

Its gonna end up costing me about $1100 to fix

$220 for diagnosis and tow
$99 16 hour lift/tool use
$225 for gaskets (head set and intake valley pan)
$240 for valve job, magnaflux cleaning (hopefully not a cent more)
over 200 for head bolts... if I can even find them
already had an injector install kit but that was about $65

To top it all off the jack azzes before me (the first owner) re used the head bolts... and over half of them on the pass side head had regular 1/2 split washers instead of the proper washers No wonder the head gasket went bad on that side.

06-26-2009, 01:47 AM
your first mistake is taking a vacation this time of year.second is not having a backup truck

Thanks for the help.

lawnboy dan
06-26-2009, 08:22 PM
buy a jap truck-you wont have problems

06-26-2009, 08:38 PM
buy a jap truck-you wont have problems

I don't know about the lack of problems, with a jap truck. But I know that you won't have much of a truck.:):):)

He's driving a 1983 F250 6.9 diesel. ( I wonder how many miles are on it after 26+ years?) Wouldn't you think that some repairs would be reasonable ?

06-26-2009, 10:18 PM
Very true Duallyvette.

I just wish I was paying out the butt for parts on this thing. The international parts guy gave me a deal at $6.15 per bolt and the washers are $2.43 So its gonna be around 300 bucks, but it was probably the reused bolts that caused this problem in the first place.

I really like this truck though.