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  1. #1

    Default Uneven exhaust flow

    Got a 87 cobalt 223 it’s got a BBC and a Alpha drive. Recently just installed the engine and I’m getting less water return out the starboard side exhaust as well as a noticeable difference in temperature between the two manifolds (one getting, and being hotter then the other).

    This is being ran off the hose, haven’t had it in water yet

    the old manifolds were replaced and the old risers cleaned and dipped in muriatic acid prior to reinstalling. The impeller is new. All hoses and everything else related hooked back up correctly.

    I suspect the starboard side riser is to blame but wanted to post to see if there is anything I may be over looking.

    Obviously there is a restriction somewhere, any input would be great before I go taking things apart and spending money.

    thanks guys!
    Last edited by 805HD; 04-22-2019 at 07:51 PM.

  2. #2
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    Default Re: Uneven exhaust flow

    Get one of those small cheap borescopes off amazon and poke around inside the exhaust
    Practicing the ancient art of ren-ching

  3. #3

    Default Re: Uneven exhaust flow

    Quote Originally Posted by o2batsea View Post
    Get one of those small cheap borescopes off amazon and poke around inside the exhaust
    not a terrible idea...

    i feel like the problem is in the elbow. But the boat didnít have any exhaust restriction or overheat conditions before I pulled the engine. Used to get good even flow of water out of both tailpipes. So that makes me think itís something else Iím over looking.

    As as I said before the exhaust manifolds are brand new. I decided to reuse the elbows hoping to save a few pennies..

  4. #4
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    Default Re: Uneven exhaust flow

    So that makes me think it’s something else I’m over looking.
    Ayuh,..... If the boat is unlevel, that can happen,......

    As for the temp differences,.... They never ever run the same temp on both sides,.....

    That said, if you dug out the risers, 'n acid washed 'em,........ They're Junk,.... Replace 'em, before they cost you a motor,....

    All that junk you dug out of 'em,.... Used to be cast iron,.....
    Any Grease is Better,... Than No grease at All....

  5. #5

    Default Re: Uneven exhaust flow

    Quote Originally Posted by bondo View Post
    Ayuh,..... If the boat is unlevel, that can happen,......

    As for the temp differences,.... They never ever run the same temp on both sides,.....

    That said, if you dug out the risers, 'n acid washed 'em,........ They're Junk,.... Replace 'em, before they cost you a motor,....

    All that junk you dug out of 'em,.... Used to be cast iron,.....
    thanks Bondo

    and yea I know I know! And your totally right but you wouldnít think that after the risers were cleaned out they would cause a restriction. I just canít come up with anything else that could be causing the problem.

    New manifolds, new risers, new impeller, new water pump new everything but the old elbows. The problem is definitely isolated to the starboard side exhaust. This boat has through hull.

  6. #6

    Default Re: Uneven exhaust flow

    Okay update**

    I removed the thermostat from its housing, started the boat and now have even flow of water coming from both exhausts. Which has me absolutely puzzled, so if anyone can shine some light on that it would be appreciated. Ran the boat for a while and she’s holding at 160f on the dash.

    My only other concern is the amount of what I'm fairly certain is steam coming out of the pipes. See video link. What could be causing this? It’s cool outside but I’m in California, it’s not that cold.

    Thanks guys, couldn’t do it without you!

    https://m.youtube.com/watch?feature=...&v=stnOb2jV3vQ

  7. #7
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    Default Re: Uneven exhaust flow

    Take a picture of the thermo housing and hose routing.


    My first thought is the "poppet balls" are stuck shut or not opening properly.

    The two hoses going from the T to the elbows, Remove from the T and check the balls. If stuck that would be a problem.

    If they are no longer round where they seat in the T the pull apart and reverse them. Note the specific thread count on the LONG screw they are mounted on.

    Report back
    Jack
    Northborough Ma
    Helping others sometimes with an attitude....haha..

  8. #8
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    Default Re: Uneven exhaust flow

    Quote Originally Posted by 805HD View Post
    Okay update**

    I removed the thermostat from its housing, started the engine and now have even flow of water coming from both exhausts.
    Although that appears to have solved the problem, I would want the thermostat in place so that your engine is able to reach normal operating temperature.


    I agree with the idea of a restriction within the spent seawater path on the Starboard side. You should have much more and more even seawater flow coming out from both exhaust tips.

    Since the elbows were not replaced (although they did undergo an acid bath), you may want to look at both the seawater transfer ports, and the elbow's spent seawater mixing chamber outlets.
    If the mixing chamber outlet is rust compromised, it may explain the reduced seawater flow on that side.

    Keep in mind (raw water cooled engines) that most all seawater will be bi-passing actual engine cooling demands, especially at low RPM and with no engine load. The correct T-stat housing provides this function.
    Perhaps post a photo of your T-stat housing and the hose routing.


    Since you used the garden hose/water muffs, I assume that you are relying on the A drive seawater pump for cooling this BBC engine!


    .
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP's

    Please... no PMs! Post your questions on the forum.

  9. #9

    Default Re: Uneven exhaust flow

    Quote Originally Posted by kghost View Post
    Take a picture of the thermo housing and hose routing.


    My first thought is the "poppet balls" are stuck shut or not opening properly.

    The two hoses going from the T to the elbows, Remove from the T and check the balls. If stuck that would be a problem.

    If they are no longer round where they seat in the T the pull apart and reverse them. Note the specific thread count on the LONG screw they are mounted on.

    Report back
    i had the same thought and actually removed the “poppets” prior to this video. I’ll take a picture and post it as soon as I get out to the boat.

  10. #10

    Default Re: Uneven exhaust flow

    Okay now Iím really confused lol I understand that the other video was recorded in the evening and that the colder weather will create more steam. The thing Iím confused about is the water return being even.

    Let me recap, the first fire after the engine install I had less water return from the starboard side exhaust. Like ghost stated I was thinking the poppet valve in the T was stuck causing less water to flow to one side so I completely removed it from the equation with no change. I then removed the thermostat just to see and that gave me more water return from the starboard exhaust.

    Today its about 78 degrees out, I started the boat and things are SUBSTANTIALLY better. Good amount of warm water coming out the pipes, even on both sides. Exhaust elbows warming up In sync warm to the touch but I can rest my hands on them. Temp gauge at idle without thermostat seems to lock in at 160f at idle 550-600rpm. Oil pressure is good 35-40psi. And the oil itself looks good. No milkshake or any apparent signs of water intrusion.

    The question now is, what changed?! And where do I go from here? Obviously things donít fix themselves or else I wouldnít be here right now lol maybe I had a piece of something that was causing a restriction that has now moved? Thatís not comforting!

    please watch the video and let me know what you guys think. All hoses and water return looks good to me. FYI video quality is not the best. Keep in mind there is more water coming out then it may seem.

    https://m.youtube.com/watch?v=UM_FNl...ature=youtu.be

    the knocking noise in the background is not coming from the engine! Itís coming from the in-line Hardin marine flappers I installed while engine was out.

    Thanks again
    Last edited by 805HD; 04-23-2019 at 03:15 PM.

  11. #11
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    Default Re: Uneven exhaust flow

    Are you certain that the garden hose/water muffs is supplying enough water?
    Is the seawater pump in good condition?
    Have you replaced the seawater pump impeller?
    Is the tube from the seawater pump to the upper unit installed correctly?
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP's

    Please... no PMs! Post your questions on the forum.

  12. #12

    Default Re: Uneven exhaust flow

    Quote Originally Posted by RicardoMarine View Post
    Are you certain that the garden hose/water muffs is supplying enough water?
    Is the seawater pump in good condition?
    Have you replaced the seawater pump impeller?
    Is the tube from the seawater pump to the upper unit installed correctly?
    I completely rebuilt the drive minus gears, impeller is new new carrier bearing and seals.

    The muffs im using are the clamp style that have the rod that runs though the water pick ups off the drive sandwiching the water pick ups off the drive between the muffs.

    I know just as well as you do the muffs off a hose is no substitute to floating in water. But I do have a good connection and the hose on FULL BLAST. I’m happy with the water return now but am worried it may come back. New elbows are definitely going on. Cheap insurance in my eyes. From the video though, how do you feel about the water return?

    Can an I drop the lower leg of the drive to inspect the impeller while keeping the upper half on the boat?

  13. #13

    Default Re: Uneven exhaust flow

    I ran the boat for about ten mins off the hose. Didn’t get above 160 water

  14. #14
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    Default Re: Uneven exhaust flow

    No explanation as to why it is good one day and not the other.

    Mercruisers typically have more flow at low rpm to one side, one elbow will be warmer/hotter than the other.

    I would not recommend running without the poppets or thermostat.

    I would also say that without a thermostat and the temp staying at 160 tells me you have a restriction somewhere.

    You should be seeing temps around 110-120 with no thermostat. When a thermostat sticks open that's is what temp you would see, 110-120*.

    So my only thought is you have a floater in the thermostat housing. A chunk of scale waiting to be found.

    Maybe a Timguy or Ricardo left a turd floating........that would reek havoc with any system..........lol
    Jack
    Northborough Ma
    Helping others sometimes with an attitude....haha..

  15. #15
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    Default Re: Uneven exhaust flow

    I would not recommend running without the poppets or thermostat.
    Ayuh,..... Ditto this, ^^^

    Without the poppets you'll get random overheat at idle, 'n the t-stat helps direct the water through the t-stat housing,....
    Any Grease is Better,... Than No grease at All....

  16. #16
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    Default Re: Uneven exhaust flow

    .........................
    Quote Originally Posted by 805HD View Post
    I completely rebuilt the drive minus gears, impeller is new new carrier bearing and seals.

    The muffs I'm using are the clamp style that have the rod that runs though the water pick ups off the drive sandwiching the water pick ups off the drive between the muffs.
    Those should be OK.

    I know just as well as you do the muffs off a hose is no substitute to floating in water. But I do have a good connection and the hose on FULL BLAST.
    Correct!
    However, you should be able to supply enough water via the garden hose/water muffs for what you are doing.
    Many times I have checked/set ignition TA (at/near 3k rpm for several seconds) with the engine using garden hose/water muffs for cooling.
    Even while most OEM's will suggest NOT doing this (basically a disclaimer), short duration increases in RPM are not an issue.

    Iím happy with the water return now but am worried it may come back.
    When you say "water return", I assume that you are speaking of the water that is exiting the exhaust system.

    New elbows are definitely going on. Cheap insurance in my eyes. From the video though, how do you feel about the water return?
    While I do see a bit more on the Stbd side, at low RPM it would appear to be OK.
    Does it even out some if you were to increase RPM?


    Can an I drop the lower leg of the drive to inspect the impeller while keeping the upper half on the boat?
    With an A drive, yes.

    As for engine operating temperature (generally speaking for an "open system" ...... i.e., raw water cooled):

    Running in River/Lake water.... engine temp should be close to 160*
    Running in Salt or Brackish water...... engine temp should be close to and not exceed 143* as to avoid salt crystallization.



    .
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP's

    Please... no PMs! Post your questions on the forum.

  17. #17

    Default Re: Uneven exhaust flow

    Quote Originally Posted by kghost View Post
    No explanation as to why it is good one day and not the other.

    Mercruisers typically have more flow at low rpm to one side, one elbow will be warmer/hotter than the other.

    I would not recommend running without the poppets or thermostat.

    I would also say that without a thermostat and the temp staying at 160 tells me you have a restriction somewhere.

    You should be seeing temps around 110-120 with no thermostat. When a thermostat sticks open that's is what temp you would see, 110-120*.

    So my only thought is you have a floater in the thermostat housing. A chunk of scale waiting to be found.

    Maybe a Timguy or Ricardo left a turd floating........that would reek havoc with any system..........lol
    well this morning I put the thermostat and poppets back in, fired her up and
    We are back to the original problem. Weak water return from starboard exhaust as well as starboard side elbow getting real hot real fast. Temps climbing quickly up to 180f on the gauge.

    I don't think the poppets are the problem because originally I removed those first with the same results. From what I can tell the thermostat is causing the issue. Cause I know if I remove that thermostat again the problem will go away again. What could it be?

    T-stat is a 140f Marine. Perhaps it’s faulty? What are the long term consequences of running without a thermostat? I boat in Utah California and Arizona rivers and lakes. There isn’t a day when I’m out there when it isn’t at least 90f. Perhaps I can remove the expanding element of the t-stat and run it that way as to keep the directional properties that it provides?

    Thank you everyone
    Last edited by 805HD; 04-24-2019 at 02:09 PM.

  18. #18
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    Default Re: Uneven exhaust flow

    The actual thermostat should have zero to do with the unequal seawater flow to the exhaust elbows. I would suggest that you have something wrong within the T-stat housing, hoses, hose routing, fittings, etc!

    Running without a thermostat will prevent the engine from reaching operating temperature.




    .
    Last edited by RicardoMarine; 04-24-2019 at 02:47 PM.
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP's

    Please... no PMs! Post your questions on the forum.

  19. #19

    Default Re: Uneven exhaust flow

    Well fellas, I am officially a idiot!

    Pulled the thermostat housing off and discovered the nipple that the hose from the impeller feeds into still had tape over it from when I painted it while the engine was apart. Hole was about 75% closed off. IDIOT!

    I almost didn't even post back, but figured you would all get a good laugh from this one... how embarrassing!

    Anyways, truly appreciate all of you helping me out. You gentlemen are all the real MVPs. Will certainly be cracking beers for each and everyone of you tonight while listening to the sweet sound of a cool running 454!

    thank you!

  20. #20
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    Default Re: Uneven exhaust flow

    Well fellas, I am officially a idiot!
    Ayuh,...... Congratulations,......
    Any Grease is Better,... Than No grease at All....

  21. #21
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    Default Re: Uneven exhaust flow

    Good job!

    By the way...... did you find any havoc reeking turds in there from Tim or myself?




    .
    Last edited by RicardoMarine; 04-24-2019 at 10:55 PM.
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP's

    Please... no PMs! Post your questions on the forum.

  22. #22

    Default Re: Uneven exhaust flow

    Hahaha

    I thought I saw one, but it was just a small piece of tape!

  23. #23

    Default Re: Uneven exhaust flow

    Quote Originally Posted by RicardoMarine View Post
    Good job!

    By the way...... did you find any havoc reeking turds in there from Tim or myself?




    .
    Ricardo, question for you. I’m in the process of replacing my exhaust elbows. It’s configured as follows... exhaust manifold, gasket, 3” riser, gasket then elbow. These gaskets come in two styles. p/n27-863724 has 2 out of the 4 water jackets sealed off and p/n27-863726 has all 4 of the water jackets open. Which gaskets should I be using between the manifold, riser and riser, elbow. ?

    When I pulled my elbows I noticed the starboard side (restricted) elbow which had poor water return had gasket p/n27-863724 while the port side (unrestricted) elbow which had ample water return had gasket p/n27-863726. Coincidence? I think not.

    Why the two two different styles?

    Thanks in advance.

  24. #24
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    Default Re: Uneven exhaust flow

    805HD

    Ricardo is the last and wrong person to ask questions about Mercruiser.

    Remember this.

    He answers questions in generalities and quotes most from the internet or others.


    His supposed area of understanding is Volvo Penta (Swedish fish)

    He lurks here for post count.......

    Based on the original Mercruiser manual (which Ricard the turd does NOT have)

    See image I have attached for 3 inch spacer gasket type. Part numbers may be old as manual is also old.

    In the image you either choose A-B-A or C

    It shows gasket between manifold and spacer is open all 4 holes. Gasket between spacer and elbow is open two holes only and restricted the other two.

    The reason for the restriction is you have cold water to the elbow from Tstat housing.

    If the water flow was only through the exhaust manifold (from bottom up) then the gasket would be open on all 4 holes on both sides of spacer.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	454 3 spacer gaskets.jpg 
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ID:	20113  
    Last edited by kghost; 04-26-2019 at 02:38 AM.
    Jack
    Northborough Ma
    Helping others sometimes with an attitude....haha..

  25. #25
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    Default Re: Uneven exhaust flow

    .............................
    Quote Originally Posted by 805HD View Post
    Ricardo, question for you. Iím in the process of replacing my exhaust elbows. Itís configured as follows... exhaust manifold, gasket, 3Ē riser, gasket then elbow. These gaskets come in two styles. p/n27-863724 has 2 out of the 4 water jackets sealed off and p/n27-863726 has all 4 of the water jackets open. Which gaskets should I be using between the manifold, riser and riser, elbow. ?
    See the image that Jack posted. Then perhaps find an image that also shows the T-stat housing and the hose routing that are the same as what you have.

    When I pulled my elbows I noticed the starboard side (restricted) elbow which had poor water return had gasket p/n27-863724 while the port side (unrestricted) elbow which had ample water return had gasket p/n27-863726. Coincidence? I think not.
    That was very likely and incorrectly put together by perhaps the previous owner.
    Both sides should be gasket-ed the same.

    ...........................
    Quote Originally Posted by kghost View Post
    805HD

    Ricardo is the last and wrong person to ask questions about Mercruiser.
    Remember this.
    He answers questions in generalities and quotes most from the internet or others.
    What is the purpose of a post like this? Does it benefit the the OP or the other members?
    Jack appears to be obsessed with me and my posts here in the Merc Section, and he has now added Tim to his list!
    Here are just a few examples of his past responses:

    http://www.marineengine.com/boat-for...ession-results

    http://www.marineengine.com/boat-for...on-Base-Engine

    http://www.marineengine.com/boat-forum/showthread.php?454362-94-4-3-Mercruiser-getting-7-5-PSI-from-fuel-pump-too-
    much-carb-flooding-after-rebuild&p=639159#post639159



    I am not a psychologist, however in my 70 years of being human and in my opinion, this type of behavior is the result of either an over-inflated Ego or a lack of self esteem, or a bit of both.
    There is no reason for any of us to feel threatened by another member's posts! If we disagree, we simply voice our opinion in a polite and an adult like manor!
    Most of us will simply disagree in an adult like manor, and we will explain why in an adult like manor.


    He lurks here for post count.......
    Post counts mean ZERO as to one's knowledge and/or experience.
    Post counts indicate one's participation only, regardless of content!


    Based on the original Mercruiser manual (which Ricard the turd does NOT have)
    Again.... a very unnecessary and immature response!

    See image I have attached for 3 inch spacer gasket type. Part numbers may be old as manual is also old.

    In the image you either choose A-B-A or C

    It shows gasket between manifold and spacer is open all 4 holes. Gasket between spacer and elbow is open two holes only and restricted the other two.

    The reason for the restriction is you have cold water to the elbow from Tstat housing.

    If the water flow was only through the exhaust manifold (from bottom up) then the gasket would be open on all 4 holes on both sides of spacer.
    Had I posted that, Jack would have likely said: "useless information! As we can clearly see from the OP's video, his "open" system feeds both the manifolds and elbows separately. "


    Jack, please take a few minutes and read how you post.
    I would hope that you can see how you sound to the other members!
    Try to find a way to not feel threatened by other's posts.
    805HD, look at these two images.
    Is there a way that you could show us how your system is plumbed to the manifolds, spacers/risers and elbows (shown by Jack), and with the T-stat housing shown in the image to the right?
    If you have a PC with MS Paint, you can manipulate the schematic to show what you have.... or print it and mark it up with a pencil.



    Click image for larger version. 

Name:	805HD Merc BBC exhaust cooling .jpg 
Views:	16 
Size:	39.5 KB 
ID:	20115
    Last edited by RicardoMarine; 04-26-2019 at 08:31 AM.
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP's

    Please... no PMs! Post your questions on the forum.

  26. #26
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    Default Re: Uneven exhaust flow

    Quote Originally Posted by RicardoMarine View Post
    .............................

    805HD, look at these two images.
    Is there a way that you could show us how your system is plumbed to the manifolds, spacers/risers and elbows (shown by Jack), and with the T-stat housing shown in the image to the right?
    If you have a PC with MS Paint, you can manipulate the schematic to show what you have.... or print it and mark it up with a pencil.


    Click image for larger version. 

Name:	805HD Merc BBC exhaust cooling .jpg 
Views:	16 
Size:	39.5 KB 
ID:	20115
    To quote the above """"What is the purpose of a post like this? Does it benefit the the OP or the other members?"" from the floating TURD

    Answer..............NOT AT ALL and you are the bug TURD who is infamous for doing so!



    Again you F'n Moron

    If you actually had Mercruiser knowledge and experience you would already know this answer...........We who do already know the answer!!!!!!!

    If you reread the entire post, your stupid, useless and post counting F'n question was already answered..........


    Stick with your Swedish fish and go away................

    The proof is in the FLOATING TURD!
    Last edited by kghost; 04-26-2019 at 09:02 AM.
    Jack
    Northborough Ma
    Helping others sometimes with an attitude....haha..

  27. #27

    Default Re: Uneven exhaust flow

    Quote Originally Posted by kghost View Post
    805HD

    Ricardo is the last and wrong person to ask questions about Mercruiser.

    Remember this.

    He answers questions in generalities and quotes most from the internet or others.


    His supposed area of understanding is Volvo Penta (Swedish fish)

    He lurks here for post count.......

    Based on the original Mercruiser manual (which Ricard the turd does NOT have)

    See image I have attached for 3 inch spacer gasket type. Part numbers may be old as manual is also old.

    In the image you either choose A-B-A or C

    It shows gasket between manifold and spacer is open all 4 holes. Gasket between spacer and elbow is open two holes only and restricted the other two.

    The reason for the restriction is you have cold water to the elbow from Tstat housing.

    If the water flow was only through the exhaust manifold (from bottom up) then the gasket would be open on all 4 holes on both sides of spacer.
    now now gentlemen letís not get crazy hahahah

    thank you for the reply! I will go this route once my new elbows show up..

    But let me ask you this, why not run the unrestricted gaskets? What would happen from running the unrestricted gaskets both sides of the riser. I only ask this out of curiosity cause in my mind more water flow would be better right?!

  28. #28
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    Default Re: Uneven exhaust flow

    Quote Originally Posted by 805HD View Post

    thank you for the reply! I will go this route once my new elbows show up..

    But let me ask you this, why not run the unrestricted gaskets? What would happen from running the unrestricted gaskets both sides of the riser. I only ask this out of curiosity cause in my mind more water flow would be better right?!
    My understanding is to control hot water flow thru the manifold to the elbow.

    Because you have the cold water inlet on the elbow, the restricted gasket restricts hot water flow from the exhaust manifold so the poppets work as this increases pressure thus allowing the colder water to elbows.

    In later designs they did away with the poppets and went to a fixed orifice.

    When there is no inlet to the elbows of colder water and all water flows up thru the manifold then there is a need for all four holes in the gasket to be open.

    That is my understanding but the design engineers would know exactly why.........
    Jack
    Northborough Ma
    Helping others sometimes with an attitude....haha..

  29. #29

    Default Re: Uneven exhaust flow

    Quote Originally Posted by kghost View Post
    My understanding is to control hot water flow thru the manifold to the elbow.

    Because you have the cold water inlet on the elbow, the restricted gasket restricts hot water flow from the exhaust manifold so the poppets work as this increases pressure thus allowing the colder water to elbows.

    In later designs they did away with the poppets and went to a fixed orifice.

    When there is no inlet to the elbows of colder water and all water flows up thru the manifold then there is a need for all four holes in the gasket to be open.

    That is my understanding but the design engineers would know exactly why.........
    finally, a explanation that makes sense. Thanks again brother!

  30. #30

    Default Re: Uneven exhaust flow

    Quote Originally Posted by kghost View Post
    That is my understanding but the design engineers would know exactly why.........
    Oh how I wish we were neighbors lol

    still having troubles. So I put brand new elbows on and have the right gaskets in the right order between the risers. And I’m still getting a restriction on the starboard side exhaust. Running at idle, the temp seems to hover around 160 give or take. Port side is returning plenty of water but starboard side is no where near enough. This is running with the drive lowered into a tub. Both pipes steaming. Nothings leaking. Water pump on the block is brand new. And the boat didn’t have this issue before the engine was pulled.

    I dont think it would be the impeller because because the problem, whatever the hell it is is isolated to the starboard side only.

    Ive eliminated a lot of variables now.. Any ideas?
    Thank you
    Last edited by 805HD; 05-04-2019 at 06:09 PM.

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