Announcement

Collapse
No announcement yet.

351 exhaust manifolds, 1989 Prostar 190

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 351 exhaust manifolds, 1989 Prostar 190

    I've got to replace the manifolds and a lot of places are out of stock. I've found a set of Sierra 18-1998-1 which would fit. Has anybody had any experience with these on a Indmar 351?

  • #2
    Originally posted by slking67 View Post
    I've got to replace the manifolds and a lot of places are out of stock. I've found a set of Sierra 18-1998-1 which would fit. Has anybody had any experience with these on a Indmar 351?
    Those work just fine. I think Barr makes them with the Sierra stamp as a replacement for the Barr FM-1-83 universal center riser exhaust manifolds. Fit is no problem. If they are available, I would not hesitate to use that issue brand.

    If you can find a kit set, I recommend that kit; includes gasket for the block and the riser and new bolts. I have seen the manifolds mounted without a gasket but I prefer gaskets in that application. Also use anti-seize on the bolts. I have torque specs if you need that data.

    The OEMs with the MC logos are long gone.

    .
    93 190
    .

    Comment


    • #3
      perfect thank you

      Comment


      • #4
        Curious, what is the cause for manifold replacement on this engine?

        Comment


        • #5
          Originally posted by RxMC View Post
          Curious, what is the cause for manifold replacement on this engine?
          Rust degrades the manifold resulting in water leaking through the manifold. Water can leak externally or more so, undesirably internally to the engine block into the oil.

          Plain old wear and tear from iron oxide hydrate.

          .
          93 190
          .

          Comment


          • #6
            Inboard online has them. That’s Indmars online parts company (and they own Barr Marine). Use code IOLROCKS for 10% off.
            Wherever you get them check shipping costs - they are heavy!

            https://inboardonline.com/ford-short...ifold-fm-1-83/

            Comment


            • #7
              That link in the post above this post is the way to go (availability and 10% off).

              Get all new plugs, elbows, and bolts. Check back here before you put the new back plugs in. There is a seemingly logical way (not) or an easy way I can share to get it right the first try with no leaks. There is a trick to it. Same with the elbows.

              .
              Attached Files
              waterlogged882
              MC Master Poster
              Last edited by waterlogged882; 11-07-2021, 10:54 AM.
              93 190
              .

              Comment


              • #8
                Originally posted by RxMC View Post
                Curious, what is the cause for manifold replacement on this engine?
                Originally posted by waterlogged882 View Post
                Rust degrades the manifold resulting in water leaking through the manifold. Water can leak externally or more so, undesirably internally to the engine block into the oil.

                Plain old wear and tear from iron oxide hydrate.

                .
                There is a water jacket that surrounds the exhaust manifold and the riser, which is mounted to the manifold with a gasket between them. The hot exhaust temps are buffered by the water jacket. Waterlogged's on point as usual: rust will deteriorate them from the inside out. Freshwater inboards can run for years and years. Boats used in salt water usually replace manifolds and risers every 5-7 years b/c the salt destroys the cast iron much quicker than fresh water. I just replaced my riser gaskets as they had a 'small' leak visible by white streaks down the sides of the manifolds. I had a machine shop grind the mating surfaces to remove the pitting that was evident....but I'm saving for replacements next year.
                Here is cutaway of a manifold (from planetnautique):
                Click image for larger version

Name:	image_14391.jpg
Views:	1
Size:	27.7 KB
ID:	2413599

                Comment


                • #9
                  Trouble is that until they actually leak it is almost impossible to know the condition of those inner webs.

                  More commonly the gasket at the top between the upper and lower manifolds leaks and allows water to drip down into the center - but silty crud builds up in there at the bottom and they corrode from within.

                  Probably should be a common thing to remove the inlet hoses and make a pressure washer fitting and while running blow those out with a pressure washer.

                  Comment


                  • #10
                    When I drained the starboard side manifold the other day about a tablespoon of iron came out with the water. Looked just like sand.

                    Comment


                    • #11
                      Originally posted by RxMC View Post
                      When I drained the starboard side manifold the other day about a tablespoon of iron came out with the water. Looked just like sand.
                      That is pretty common. As the sand changes to chunks the size of pennys, nickles and quarters you'll know there is serious rust going on.

                      Comment

                      Working...
                      X