04 Mach 1 Coolant leak

rabidscoobie

10 Year Member
Jun 21, 2007
616
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College Station,TX
My 04 Mach has a coolant leak from the metal hose that runs under the shaker on each side to just behind the water pump and pushes into the manifold. No clamps or anything,just pushes in.

This summer I had to replace the water pump and ever since then I get a small leak on the driver side of that metal hose where it presses into the manifold. I lose about a 1/2-1 cup every month but I cant seem to find a way to stop it.
There are no seals or gaskets that go there.
Its not damaged just a small leak.

Any ideas what happened or maybe what I might of done wrong?

This pic shows the the hard lines Im talking about,this is just a random pic from the web,not my car.
 

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The Ford service manual says there is an O-ring in that location. While I don't know for certain but I would think that a leak in that location might be fixed with a new O-ring.

>>>
  1. NOTE: Do not cut the O-ring seal during tube installation into cylinder heads (6049) or engine coolant leakage may occur.
    NOTE: Wipe the O-ring sealing surface on the cylinder heads with a soft cloth, if necessary and lubricate the O-ring seal. Use premium engine coolant
 
The Ford service manual says there is an O-ring in that location. While I don't know for certain but I would think that a leak in that location might be fixed with a new O-ring.

>>>
  1. NOTE: Do not cut the O-ring seal during tube installation into cylinder heads (6049) or engine coolant leakage may occur.
    NOTE: Wipe the O-ring sealing surface on the cylinder heads with a soft cloth, if necessary and lubricate the O-ring seal. Use premium engine coolant

Thanks I'll have to check again but today I didnt find any o-ring on either tube but only one side seems to leak. Guessing just an average o-ring. Hopefully not a speciality ring. The bushings that go into the shaker are something like $18 each.

Ill have a look again in a day or two.

thanks again, hope thats all it is.
 
Ok well I got around to it this weekend and yes the O-ring was leaking. The o-ring was so flat it looked like just part of the black metal tubing.

Bad news is I was still leaking coolant and it was a tough leak to locate. The oil cooler gasket just above the oil filter, so I guess I get to pull that all apart soon,doesnt look all that fun. Doesnt look hard either.
 
Similar issue for me today.......

I’ve read many of the posts about these o rings that fit on the metal horseshoe shaped tubes that go into the Mach 1 engine. I’ve tried finding them at Ford & AdvanceAuto, and tried an assortment of o rings but none fit. Original was drip, drip when I put it back into hole. I read they should be replaced anytime the assembly is taken apart. Most of the replacement o rings I found available were too small, or are two big and the metal piece won’t go into hole even when lubed.

I noted the o ring I pulled off is kind of flat cut and none from the auto parts store are the flat cut type. Originally, I thought the o ring had become flat from being in the tube for the past 15 years. But, someone posted they needed to be flat cut or they wouldn’t seal tight....drip,drip.

Has anyone found these rings at a local franchise auto parts store or do they have to be ordered online (eBay).

And, a part number of 391533-s100 is thrown around. Is this the part number for flat cut type o rings?
 
Similar issue for me today.......

I’ve read many of the posts about these o rings that fit on the metal horseshoe shaped tubes that go into the Mach 1 engine. I’ve tried finding them at Ford & AdvanceAuto, and tried an assortment of o rings but none fit. Original was drip, drip when I put it back into hole. I read they should be replaced anytime the assembly is taken apart. Most of the replacement o rings I found available were too small, or are two big and the metal piece won’t go into hole even when lubed.

I noted the o ring I pulled off is kind of flat cut and none from the auto parts store are the flat cut type. Originally, I thought the o ring had become flat from being in the tube for the past 15 years. But, someone posted they needed to be flat cut or they wouldn’t seal tight....drip,drip.

Has anyone found these rings at a local franchise auto parts store or do they have to be ordered online (eBay).

And, a part number of 391533-s100 is thrown around. Is this the part number for flat cut type o rings?


Ok the reason the O rings are flat is from being pushed into the holes they go into and then heated.
I didnt goto Ford to get mine. I went to Napa and there they have it were you buy single Orings that are resistant to oils and chemicals and were something like .50 cents.
I cant remember the size I got but I just took an old one and matched it up, so far no more leaking.

Now for the actual Ford O rings, look closely at the pics, they are not flat.
https://parts.ford.com/shop/en/us/seal-7816547-1

Or here:
http://rover.ebay.com/rover/1/711-5...0001&campid=5335821607&icep_item=331566009377

As you can see they look lkie normal O rings and not flat,flat is just from being shoved into and heated from the motor.

Now my issue is I need the flex tube that goes on the shaker scoop and Ford no longer makes them and used ones are just as trashed as mine.

Its the scrunched part of the assembly here:
https://www.fordpartsgiant.com/parts/ford-tube-asy_3r3z-9a624-ad.html
Ford Part No.: 3R3Z-9A624-AD
 
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Also I forgot to add that the pipes do not push easily into the holes. Even with my old ones that were leaking it did not slide in easily.
I just got a 1"x 2" short board and a rubber mallet, set the board on the top of the pipe and tapped the wood(just dont wail on it) with the mallet.
But I had to do the same with the old o rings to so I didnt think much about it.