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Tips on replacing lower intake

  • Thread starter Thread starter 1993SSP
  • Start date Start date Jul 27, 2007

1993SSP

Founding Member
Sep 5, 2001
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Ky
Jul 27, 2007
#1
  • Jul 27, 2007
  • #1
Any tips or preference on gaskets and sealing procedures for the lower intake, I will be adding a typhoon upper and lower to my car soon, I thought I recalled using black silicone or something similar on the ends instead of the gaskets, suggestions welcomed........ thanks
 

hogt2

Founding Member
Oct 28, 1998
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Montgomery,IL.(West of Chicago)
Jul 27, 2007
#2
  • Jul 27, 2007
  • #2
Just use rtv on the end rails and no gaskets. Put a good bead on the rails and extend the bead up the head until it contacts the intake to head gasket.
 

1993SSP

Founding Member
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Jul 27, 2007
#3
  • Jul 27, 2007
  • #3
Thanks,!
 

Aliate X

Member
May 9, 2005
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18
Rockland NY
Jul 27, 2007
#4
  • Jul 27, 2007
  • #4
dont skimp on it either, put a good thick bead on it man, I just smeared it and it leaked oil out the back.
 

Blandnuts

I don't swallow; I only swoosh
Founding Member
Aug 21, 2000
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FloorDuh
Jul 28, 2007
#5
  • Jul 28, 2007
  • #5
For the end pieces I used the rubber gaskets with a small bead of rtv. I've heard of all these wonderful stories of use cork, use gasket sealer, use rubber gaskests..... I will note that using cork is a pain when you need to take it off and using just rtv will leak if your ventilation system isn't up to par.



Fred
 

SMOKEDYA

20+ Year Stangneter
Jul 13, 2003
3,637
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79
Tucson AZ
Jul 28, 2007
#6
  • Jul 28, 2007
  • #6
I used the gaskets on the sides and for the front and rear use straight up rtv. ONLY USE THE RIGHT STUFF RTV! From permatex! It's spendy but is a 100% leak proof if done right. A can that is 7oz will set you back about $15.00. BUT WELL WORTH THE PRICE. Its in a black can. I've done about 10 cars with this stuff and 100% seccuss no leaks! peace



john
 

jrichker

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Dublin GA
Jul 28, 2007
#7
  • Jul 28, 2007
  • #7
Vacuum line connections:
One large vacuum line from the upper front goes to the carbon canister

One large vacuum line from the rear goes to the vacuum tree.

One small line in the front feeds the Smog pump solenoid control valves on the rear of the passenger side wheel well..

One small line in the rear goes to the fuel pressure regulator.

One small line in the rear goes to the EGR suction regulator.

One large line in the rear goes to the PVC valve.

Diagram courtesy of Tmoss & Stang&2birds - Typical Vacuum Routing for a Fox stang 5.0:


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Here's some tips...

Tools: a good torque wrench is a must have item. A razor blade scraper that holds a single edge razor blade from Home Depot or Ace hardware is another handy thing. Get a Chilton or Haynes shop manual - you'll need it for the bolt torques and patterns. The intake manifold has an especially odd pattern. You'll need access to a timing light to set the timing after you re-stab the distributor. Look in the A/C repair section for the fuel line tools. They look like little plastic top hats. You will need the 1/2" & 5/8" ones. The hat shaped section goes on facing the large part of the coupling. Then you press hard on the brim until it forces the sleeve into the coupling and releases the spring. You may need someone to pull on the line while you press on the coupling. Put some motor oil on them when you put the line back together.

The A/C Compressor comes off with lines still connected. Mark all the electrical, smog and vacuum lines with tags to help you remember where to re-connect them. If you have a digital camera, take several pictures.

Whatever you do, don't skimp on cleaning the gasket surfaces. New gaskets need to seat against bare metal and not the residue left from the old gaskets in order to seal leak free. This is the most time consuming and tiresome part of the job. I suggest that you make good use of a shop vac while you are scraping and cleaning to avoid getting the old gasket material lost inside the engine. Look for little things that need to be replaced like the short hose from the thermostat hosing to the water pump, damaged vacuum lines and hose clamps that are rusted or broken.

Plan on cutting the thermostat to water pump hose, or removing the thermostat housing. Also plan on removing the distributor to get clearance to remove the intake manifold. Remove #1 spark plug, stick your finger in the spark plug hole and crank. When your finger gets air moving past it, stop cranking. Turn the engine until the timing marks line up with the pointer. Now you can pull the distributor out.

My favorite trick that saves time and effort is the stay in place gasket. Be sure that you scrape (don't use a wire brush) all the old gasket material off, then clean all the surfaces with acetone or MEK.

When the surfaces are clean, use weather strip adhesive on the head to manifold surface. Also use the weather strip adhesive on the side of the gasket that mates to the head. When you are done, the head surface and the gasket surface that mate together will have weather strip adhesive on them. Follow the instructions on the tube or can and when it gets tacky, press the gasket down on the head.

Clean the area where the rubber rails mount to the block in front and in the rear with more acetone or MEK and do the same trick with the weather strip adhesive that you did to the heads.

Coat the rubber seals and the gasket area around the water passages with lots of Blue Silicone gasket sealer and put it together. TADA! no leaks, and no gaskets that shifted out of place.

Fuel injector seal kits with 2 O rings and a pintle cap (Borg-Warner P/N 274081) are available at Pep Boys auto parts. Cost is about $2.74 per kit. The following are listed at the Borg-Warner site ( http://www.borg-warner.com ) as being resellers of Borg-Warner parts:

http://www.partsplus.com/ or http://www.autovalue.com/ or http://www.pepboys.com/ or http://www.federatedautoparts.com/

Most of the links above have store locators for find a store in your area.

Use motor oil on the O rings when you re-assemble them & everything will slide into place. The gasoline will wash away any excess oil that gets in the wrong places and it will burn up in the combustion chamber.

Plan on doing an oil change within 2 hours of run time on the engine. This will get the debris and coolant out of the oil pan.

Consumable items:
Upper manifold gasket
Fel Pro 1250 or equal lower manifold gasket set.
Short formed hose between thermostat hosing and intake manifold
6 ft 7/64" or 1/8" vacuum hose
2 ft 1/2" heater hose
1 1/2 ft 5/8" heater hose
Blue Silicone sealer
ARP antiseize or equal for the bolts
4 each 3/4" hose clamps (spare item in case the old ones are bad)
4 each 1/2" hose clamps (spare item)
 

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Fett

New Member
Nov 2, 2004
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Jul 28, 2007
#8
  • Jul 28, 2007
  • #8
SMOKEDYA said:
I used the gaskets on the sides and for the front and rear use straight up rtv. ONLY USE THE RIGHT STUFF RTV! From permatex! It's spendy but is a 100% leak proof if done right. A can that is 7oz will set you back about $15.00. BUT WELL WORTH THE PRICE. Its in a black can. I've done about 10 cars with this stuff and 100% seccuss no leaks! peace



john
Click to expand...

MotorCraft makes a silicone for use on diesel engines that works great also, it is part number ta31. It is a gray silicone that holds anything. I use it on everything from sealing the intake end rails, to water pumps, even a hole in a transmission. My mothers 99 Cougar threw a shift bolt through the case, and I used a small peice of a tin can to cover the hole, and diesel silicone to seal it to the case. So far it hasn't as much as seeped a drop in 5 years and 90k miles. On the same car I put a water pump on it that didn't come with a gasket, so I smeared a bead on the pump and a bead on the housing, let sit for about 10 minutes, then put together. Again, no leaks in over 50k. Stuff works amazing. It was recommended to me by guys who own a performance shop and build turbo engines.
 
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