Hey all long post buckle up!!

I purchased a 78 f150 351m 2wd long wheel base truck 2months ago. I bought the truck running and driveable. The person I got it from said the engine and transmission were both rebuilt about 1year ago. Well truck has been great!! I was driving home cool evening, the trip would have been about 50miles one way, I get 2/3rds through the trip the truck starts sounding different and not responding to throttle as much so I let off the gas and push back down and sure enough it's not responding above like 20-30 mph.
Luckily I'm right at an exit ramp I take it slow down truck still running but now it's smoking. I got onto the on ramp for the tow truck to find and park truck shut it off by now it's smoking very heavily. I get out go to open the hood to see my damage, but typical Ford truck I have to do the hood think so by time I got back to latch explosion. Upper radiator hose blew.
Backstory, truck drive instate 45-55 miles from where I bought it to my work then another 30miles to my house (break in between) then drove interstate 50miles to were it was all in great time and no issues at all. I don't know what my temp was bc one of the P/O took the wire off the thermostat housing and I don't know where it is to put it back on
(If anyone has routing I'd love a picture) fast forward I bought new radiator w built-in electric fans got those wired in got new belts bc the one for a/c was missing (it works btw) got all that installed started the truck and now is screams and sounds like someone hitting a bell so logically I start removing the belts I put on. I get all the three off and still squeak/squeal. I looked at the crank pulley and harmonic balancer and looks fine?? It didn't make this sound before now it does help!!

 

is the noise definitely coming from the front of the engine? when the belts came off, did it bend the transmission cooler lines so that they are in contact with the crank pulley? (can't really tell from the pic)
I assume you've checked the oil? did it get hot enough to hurt the engine internally?

 

It is definitely the front end somewhere, and no it didn't get too hot running it's been 45°f here at night and engine was cold prior to starting. It only ran seconds at a time to see if it would keep squealing. And I turned on my rad fans just to be sure. I'll check the oil when I get in this evening, prior to noise it was on the full level and clear.


Also the lines weren't bent in any way so there shouldn't be interference, but I'll double check that too!

 

Are you sure that pulley isn't rubbing a cooler line?

Also, my '77 temp sender is in the block just to the passenger side of the fan/water pump. I removed it to use a tube type mechanical temp gauge.

 

I know where the sensor is I don't know where the wire for it is. It was removed when I bought the truck and no one has a picture of wire color or routing.

Also I was informed that the screws from where I removed the fan and clutch may not be tight enough and will cause a ringing and squeal. I'll check when I get home

 

So if it lost power, was smoking the belts came off and it blew a radiator hose it was way overheated. this can cause a multitude of serious problems but squealing with no belts on it shouldn't be one.

It's hard to say without seeing it but the only external thing turning on the front of your engine now is the distributor and that won't squeal for long before it locks, a bad vacuum leak can squeal as well . now anything else making noise is internal .

It's check the oil good for water or metal. if it's clean you might have a chance it's an easy fix but I wouldn't bet on it.

 

Maybe was the line in your post lead me to even mention it? Yes, if the 4 bolts are left loose on the pulley after fan removal, it'll drop and contact the crank pulley. It is being pulled down too if a belt is then run on it.

 

tbear853 it's all good, do you have a picture of the routing for the sensor wire hopefully I can find the wire and plug it in an see if that sensor works.

 

No picture, it was just a single wire that had a black rubber molded L shaped connector on it, it was wrapped in the harness wrapping that I believe is in your picture just between the water pump and alternator, near a loosened bolt it looks like.

 

Not as loud for the squealing part but you can hear the ringing well

 

have you crawled underneath to see if the exhaust is rubbing on the frame or anything else?

 

Do you have any oil pressure ? are the belts still off ?

unless you can find something rubbing on whatever you've done with the front of the engine pull the distributor. if it's okay you might as well start pulling the engine.

I had a overheated FE once with a collapsed piston trying to seize that sounded just like it.

 

I got the ringing to go away Alt and P/S were just loose enough. But the squeal is still there. It's now only with raising RPMS. giving it gas and is it at idle before increasing throttle.

My oil pressure gauge doesn't work just like my temp gauge. which thank you to whomever pointed it out in my picture I tried to move it to a different sensor and the end was too small for a good connection.

 

Sounds like piston slap in the second video , consistent with an overheated collapsed piston. or , it could be fuel pump noise I can't say from the video.

The first video is the worst , I can't think of anything it could be that would make you feel better.

If you're not ready to declare it dead yet I'd do a compression check .

 

It's a rythmic knocking or slapping noise for sure. The squeal .... I'd suspect a bearing trying to seize. It sounds really sick. Before I started it again, I'd hook up a real non electric type oil pressure gauge even if just temporary. Doesn't help with the squeal, but the slapping could be timing chain, but seems too regular to my ears. Could be fuel pump noise but I've never heard one quite so loud .... but maybe.


When my 351M needed the bearings replaced, it was the very first main bearing that was worn the most, only had 75,xxx miles on it, no knocks but the lifters were a little loud from what turned out to be 4 psi on a real gauge, that's just almost 5 psi. I did the bearings (rods & mains) on my back in the yard, oil pump too. Saved the crank. Was just over 30,xxx miles ago in November 1992. Mine didn't overheat or make that squealing or knocking sound though.

Good Luck ........ Really.