Hello and good morning.

I picked up a 4.9L Air Box yesterday at the boneyard to replace my 5.OL 1987 unit. The 4.9L has only the breather connection from the valve cover.

There is a vacuum line (red) on my 5.0L that leads to the Plenum for the injection system so I want to remove and cap it.

Will this cause any problems?

I need your help and expertise.

Thank you guys!

Boon

 

Only red vacuum line I can think of on these trucks is the FPR to "T" on the plenum. You may want to reconsider what vacuum lines you are wanting to cap off. Also, I grabbed a airbox and breather(snorkel) for my 5.0 and didn't need to make any changes other than that.

 

Thank you for the information.

I will look at it again as I did not take the time to thoroughly check the vacuum line. It is red and is on the top of my 5.0L Air Box.

I suppose that I could remove the check valve and cap it off there as I may need it again someday.

What do you think? Did you notice anything after changing the Snorkle?

Take care and Godspeed.

Boon

 

I forgot to add that I picked up my snorkel and airbox plumbing from a '91, 4.9, 300. I have a '92, 4.9 as well, but for the life of me I can't see this red line from the airbox to the plenum. My apologies as I may have been thinking it was the red vacuum line that runs from the Plenum to the FPR on our 302's.

Could you post a pic of the line? Perhaps another member can guide us both. I feel like I don't know and hate being lost into something..

 

I am waiting for a forum brother to teach me how to post pictures as I do not know how.

Our 5.0L's have 2 vacuum lines on the very top of the box. One is for the original snorkel which is no longer needed as the new snorkel does not need it.

The second (red), has a check valve between the box and the firewall and this is the one to cap. I just assumed that the red vacuum tube runs to the plenum. I will track it down today.

What is the FPR?

Thank you!

Boon

 

Where did you cap the red vacuum line?

I thought that perhaps capping it at the check valve between the box and the firewall may be a good place considering I may need it again someday.

What do you think?

Thank you!

Boon

P. S. What is a FPR?

 

How about a FTE sister.......https://www.ford-trucks.com/forums/1...r-dummies.html

 

If I'm not mistaken the airbox sits on top of the motor in the '87 model(or was that '86?) so it's totally different than the later models and that's probably why the OP got the box and snorkle and hopefully he also got a set of 5.0/5.8 intake tubes as well. I can't think what those vacuum lines could be except maybe part of the AIR injection system but a picture will certainly sort it out.

 

Hello and good morning Conanski.

My Air Box is mounted next to the Anti-Freeze overflow and Windshield Cleaning fluid. I have the 2 long intake hoses to the Throttle Body.

One of the Vacuum Tubes goes to the stock snorkel.

The one in question, (red) goes to a check valve between the box and firewall. It continues across the Fire Wall. I have not actually pulled it from the covering so it may lead somewhere else.

I have not pulled it from the Loom but it may be the one on the Plenum for the Fuel Injection.

Thanks!

Boon

 

I sincerely apologize for not acknowledging our forum sisters and I hope that I did not offend anyone.

Thank you!

Boon

P.S. I tried to upload pictures from UserCP to no avail so I am working on Photobucket and I do not have it figured out either. I have 4 pictures saved to Photobucket, my Desktop, program files and finally Windows Photo Gallery.

 

The 4.9L Box does not have these lines from the factory as I noticed on a few at the Boneyard. The only line is the breather line from the valve cover that mounts on the firewall side of the box. Perhaps it came on the V8's when they came out with the EFI System. My 87 also has a "foil" hose from the heat shield on the exhaust manifold that leads to my stock 5.0L snorkel.

I do not know how to post pictures yet but I am working on it.

Thanks!

Boon

 

The red vacuum line you are talking about operates the heat riser diverter in the airbox inlet tube. I think that the part in the top of the airbox lid is a thermostatic valve to regulate when the heat riser valve is opened. As far as I know, this feature was only used in '87, otherwise the airbox and inlet system is in the same position as later years. I blocked off this vacuum line on my truck and have not experienced any cold-weather problems.

 

Hello and good morning.

My 87 5.0L has two vacuum lines: One going to the heat riser diverter on the top of the snorkel. Directly underneath is the "foil pipe" that runs to a heat shield on the exhaust.

The second line which I am describing starts on the top of the air box running to the fire wall with a small check valve inline. This is the line that I need to cap.

I thought that it is the same red vacuum line that is on top of the Plenum for the fuel injection system but I have not confirmed this.

As you stated this setup may be exclusive to the 87 and/or the 5.0L. Just speculation but perhaps the heat riser diverter remains closed until the engine reaches operating temperature because if it were open it would take more time to obtain operating temperature.

The 4.9L Airbox that I am installing does not have a heat riser diverter or vacuum lines. There is only one connection on this airbox and that is for the hose that connects the valve cover to the firewall side of the airbox.

Thanks for your help!

Boon

P.S. I will be at the boneyard tomorrow for a 3G alternator so I will look at some of the Ford engines to see if I can find the same stock setup that I currently have and note the year.

 

You cannot post from your local hard drive, they have to be hosted someplace else online (FTE Gallery, Photobucket, etc.).

This is the key to posting the desired photo on FTE or other online forums:

Now click on any of the photos you just uploaded to your album and scroll down to the bottom, you will see two code lines. Be sure you use the BB Code line for copying and pasting into your posts.


To get the photo into a post you just simply copy and paste the code like this

 

Hello and good morning rla2005

Thank you for the education as I most certainly need it.

I am going to upload the pictures from Photobucket as I opened an account with the website.

Thanks again and thank you for all of the help you have given me on my threads and replies.

Boon

P. S. I saved this page so I can use it for future photographs. I forgot to inform you that my pictures are JPEG. Will it work?