Hey Gang,
It's my first attempt at replacing the fan belts on my 1985 Ford F150, Inline 6.
I never even thought to inspect until one of the belts (To a compressor I believe) started squealing very loudly about 2 weeks ago.
(I don't drive it everyday)

So, I have a look and i see 4 belts and I (of course) do not see a spring loaded tensioner. I wrongly assumed all vehicles had one.

Any quick advice on swapping out the belts? Do the individual components all have to be loosened and swung to where the belt is loose, then old belts come off, new ones go on, everything is tightened back up?

Also, it looks like either the fan has to come off, or I have to snake the new belt around the fan somehow.

Thanks in advance, pictures to follow...

 

This is old school. so yes, things have to be loosened. And some of this stuff can be difficult to figure out which bolts to loosen to get them to move, you will have some in front and in back.

Take a picture before you start taking the belts off.

You should be able to snake them around the fan inebtween the fan shroud and the blades.

Make sure to spin and wiggle all your components once you get the belts off. Any play or roughness is a sign something is going bad.

I would get quality Dayco belts. You can run the cheaper belts, but you will find you will have to re-tighten the cheap belts several times in the next few weeks to get them to quit slipping. The higher quality belts only once if they need it at all.

For the least amount of trouble, mark the belts where they came from and take them with you to the store. With all the different options, it can be confusing what belt you need, so just make sure they give one the same length as what you had.

 

That's great advice, thanks a ton for that. Picture coming in a few min.

 

Shot from the drivers side

the truck doesn't have A/C...is this an A/C compressor?

shot from above from the passengers side

From the alternator, under the myster compressor

looking at the fan from the drivers side

 

likely emissions air injection pump

 

That's a smog pump.

 

That probably makes sense...it looks like an A/C compressor but this truck has NEVER had A/C, so it was a bit confusing.
Now I think I need to return the belts that I bought because he asked if I had A/C, I said...I think I do...

Thanks!
J

 

Thank you!
I've got antique plates and live in Virginia...as long as I own it, It'll never have to pass an emissions test...
Do I really need a smog pump?
Is it recommended to lose the smog pump off of an 85 inline 6 cylinder?

 

it is called an air injection pump and it does perform part of emissions.

 

You may have to make another trip. There is no guarentee they have the correct belts listed that are on your truck right now. That is why I said take them with you. Or get the numbers off of them.

All your belts will have a 13 or a 15 in the number. That is the belt width in mm. Most Fords use a 13mm wide belt or a 15mm wide belt. The other part of the number is the length of the belt in inches.

So a 15mm wide belt that is 40 inches long will either be a 15400 or a 40015 belt. A belt that is 40 1/2 inches long and 15 mm wide will be a 15405 or a 40515.

A belt that is 13mm wide and 27 1/2 inches long will be a 13275 or a 27513

 

Ah, the much maligned air injection pump, aka smog pump.

Follow the lines out and see where they go. On my 351W, one function of the air injection system is to spray cool air on the back of the exhaust valves. Engines of this era were calibrated slightly lean, which causes high combustion temperature. Helpful for emissions, but kinda tough on certain components such as exhaust valves.

Whenever somebody joins the "Rip Out All That Pollution Crap" club, the poor air injection pump is usually the first thing to go. It takes a fraction of a horsepower to spin the pump, so the performance increase is virtually nonexistent. You also lose the benefit of cleaner emissions, but practically nobody cares. You also lose the exhaust valve cooling (if so plumbed), but this may not be a big deal. I haven't heard any horror stories about burnt valves, but who knows. I work my truck hard at full gross weight, so I'll take any advantage I can get.

FWIW

 

Ya another myth about the air pump cooling exhaust valves. It actually increases exhaust temps as the fresh air injected to the exhaust causes any unburnt hydro carbons to combust as they come out of the cylinder.
If the emissions system is functioning properly and no one has messed with it , and you are not looking for more power leave or better fuel economy leave it in place. But it is one of those thing if you start tering parts out the whole system will need to be re-gigged to compensate. The only exception is the air/thermatic system it can come out with out affecting anything else except the cat, as that will have to come out as well....

 

Does the air pump do more than assist the cat? Also can I bait you into discussing emissions systems with me? Been thinking about starting a thread.


Also OP most everything should have a radiused support bracket, top or bottom that's slotted. It's used to set the tension. Should just have to loosen the bolts and let them slide on the arms to get the belts free.

 

It does assist the cat to a point, but primarily reduces the load on it increasing it's efficiency.. The thermatic system burns unburt hydrocarbons (fuel) in the exhaust manifold/port by providing ambient air (oxygen) allowing the unburnt hydrocarbons to combust . With out the thermatic system the cat can be can be over loaded with unburnt fuel, in turn over heating it and and melting it internally. It also increases the temp of the exhaust shortening the time till the cat starts to "cook off" on warm up...

And any discussion of emissions system is a good conversation especially on these trucks where so much was trying to be accomplished with mechanical control systems. Some are pretty convoluted and not all worked as intended by any stretch and more than few were in place for show and the manufacturers cheated their way past emission testing.... not that, that has ever happened