How to change intake on 4.6L V8

[fordysenior]

I'm in the process of replacing my intake manifold using the Dorman product. I took off the factory original and also noted the noise reducer/insulator is falling apart. Per your comment I will throw it away but I'm curious to know if anyone has noticed the engine being louder or hearing new "unwelcomed sounds" since the noise insulator is not longer in place.

I have not noticed any noise problems or weirdness from it. The biggest weirdness was when I touched that plastic thing and it broke off some pieces -- then I wondered 'oh no, what did I do now'. Glad it's gone.

 

[ROBinGa]

I changed my 2003 XLT 4.6 manifold yesterday. I ordered a Ford manifold from an eBay Ford parts dealer and it was $308 delivered. I bought FelPro gasket kit which also includes thermostat oring. The job went well using lots of guidance from this thread and others on this site. It looks very intimidating but you can do it with very few tools and basic mechanical knowledge. I also changed the spark plugs, put on new belt and put new bottom orings on injectors. Here's a couple observations and tips:

• Use silicone spray on all the vacuum and rubber hoses to help with removal and let soak for a few seconds before
• No need to remove cables and brackets from throttle body. Just remove connectors, vacuum tubes, EGR bolts and after unbolting lift it up to set on windshield cowl and support with bungee. Very easy this way
• There are two places on back of manifold where a wiring loom is attached and it makes getting fuel rail line that goes to other bank hard to get off and eventually the manifold itself hard to get off. You need to be mindful of how it's connected to rear of manifold and find best way to get that loose. Mine was brute force and breaking the plastic connector which probably wasn't right but what happened.
• When you start it first time it may run very very rough depending on how much cleaner and solvent you use to get intake mounting surface super clean. I used 3 cans of carb cleaner and my engine ran so bad at first I thought I screwed something up big time. It smoothed out eventually and runs great now.
• The fluid in my plug wells was definitely coolant mixed with grime. All wells on driver side had it, none on passenger. The internal gasket in the manifold coolant channel where thermo housing seats to head had warped and was allowing coolant to seep between manifold and the head surface and it runs along surface and deposits in spark plug wells. New manifold and new gasket set should solve my problem for another 130,000 miles

 

[SyberTiger]

I added several installation tips specific to the 2002 4.6L right HERE using the Dorman aftermarket part since this thread is generally concerning the 4.6L and some people have questions about the 2003-2005 models which may not apply to the 2002.

 

[edcantu9]

just curious why does dorman/amazon 615-175 says this dosnt fit 2003 explorer v8 4.6l?

Where you able to find an answer to this? Did it fit your mountaineer?

 

[Number4]

Where you able to find an answer to this? Did it fit your mountaineer?

Dorman makes a model for the ‘03-‘05 now.
615-775
Vs. the ‘02 615-175.

The difference is in the size of a screw in nipple fitting.

 

[edcantu9]

Dorman makes a model for the ‘03-‘05 now.
615-775
Vs. the ‘02 615-175.

The difference is in the size of a screw in nipple fitting.

Thank you for taking the time to reply. Amazon does not have the 775 in stock, and it is about $60 more expensive than the 175 (which is in stock).

Did the 175 work for your 03 Mountaineer?

 

[Number4]

Thank you for taking the time to reply. Amazon does not have the 775 in stock, and it is about $60 more expensive than the 175 (which is in stock).

Did the 175 work for your 03 Mountaineer?

I purchased the 775 from Rock Auto. I watched the price go up and down over month before buying it.

 

[edcantu9]

I replaced the intake manifold. Now I have a leak in the back passenger side of the manifold. I clean the area good. No leaks elsewhere

torqued manifold in two stages as directed.

did pressure test , i can see the coolant leaking out that corner.

I have an 03 mountainneer. any advice? used dorman 615-775.

 

[Number4]

Did you seal the little holes in the heads? Where the old gaskets tabs went?

 

[edcantu9]

Did you seal the little holes in the heads? Where the old gaskets tabs went?

Hi thanks for taking the time to give me some advice, was that part of the instructions? There was a sheet that came with it, but maybe it was not made clear to me.

I know the holes you are talking about, they are on the aluminum surface. Should I have stuck some RTV in those holes?

EDIT: I see the sentence that states to fill in with RTV. It says that sometimes the original OEM gasket alignment holes in the head were placed in a position near or under the dorman gasket centerline to fill it in.

I read it before hand but didnt quite understand what it meant. How is a person to be certain that these alignment holes are not near the dorrman gaskets?

 

[edcantu9]

Hi thanks for taking the time to give me some advice, was that part of the instructions? There was a sheet that came with it, but maybe it was not made clear to me.

I know the holes you are talking about, they are on the aluminum surface. Should I have stuck some RTV in those holes?

Doesnt make sense though because its only leaking in that back passenger corner.

 

[Number4]

Hi thanks for taking the time to give me some advice, was that part of the instructions? There was a sheet that came with it, but maybe it was not made clear to me.

I know the holes you are talking about, they are on the aluminum surface. Should I have stuck some RTV in those holes?

EDIT: I see the sentence that states to fill in with RTV. It says that sometimes the original OEM gasket alignment holes in the head were placed in a position near or under the dorman gasket centerline to fill it in.

I read it before hand but didnt quite understand what it meant. How is a person to be certain that these alignment holes are not near the dorrman gaskets?

You should be able to see. Best to just put some rtv gasket maker in them.

 

[edcantu9]

You should be able to see. Best to just put some rtv gasket maker in them.

I can't get the leak to stop.

The area is smooth, im torquing like supposed to, but it wont stop leaking. I am thinking putting a 1/4" bead around the coolant port and then set the intake on top.

You think that would seal the leak or its a waste of time?

 

[Joe in NY]

Are you getting the area as dry and clean as possible ?

Are you letting everything sit for 24 hours still dry for curing and then doing a light torque check afterward ?

 

[edcantu9]

Are you getting the area as dry and clean as possible ?

Are you letting everything sit for 24 hours still dry for curing and then doing a light torque check afterward ?

Yes I let it sit for 24 hours. But I read the instructions on the rtv. It says to put rtv on, then lightly torque it, after 24 hours then torque to full value. I torqued it to 18ft right away. Maybe that was my mistake?

 

[Joe in NY]

Well if the RTV says light toque and you didn't the first time try it the second time.

When you torque it right down you squeeze out all but the very least amount of RTV. When lightly torqued there is more there to setup and cure

 

[Number4]

I think you have a bad intake. Shouldn’t be this much problem. You sure all the gaskets were present?

 

[edcantu9]

I think you have a bad intake. Shouldn’t be this much problem. You sure all the gaskets were present?

I ended up putting the old OEM one back on and bought new upper intake manifold gaskets and it sealed it right up. Learned lesson, no more messing around with Dorman products.