Steam

[boatdock]

I have a 1989 5.4L Mercruiser with Apha I, that started steaming and running hot while out in the bay, i had the water pump and spark plugs changed since then, but engine is still not running correctly. I have the ear muffs and garden hose on it while running it in the yard, the port side of the engine gets very hot while the other side is at normal temp. Steam starts coming out of the outdrive after running 10 min, the boat is also missing slightly and making a ticking noise by the rear exhaust cross connect. Do i have a blown head gasket? or Cracked head?( Oil looks fine) and what is that noise? SOS

 

[Trent]

Re: Steam

Right after you run it. Remove the sparkplugs and look and see if water is on the plugs. Or that one looks VERY CLEAN. Also a compression check would be in order. You could have a bad riser thats caused water intrusion. Do the above and come back.

 

[Bondo]

Re: Steam

I'm with Trent.... You've got a Rusted out, time to Replace, set of Manifolds,+ Risers...<br />The ticking Noise is Most Likely the Exhaust Flappers.... The rubbers are Burnt Off...

 

[boatdock]

Re: Steam

Thanks Trent, i will give it a shot and report back. i thought for sure it was the heads because the first time it happened the RPM's dropped and steam started coming out of the water. <br /><br />Bondo are the exhaust flappers important? or can i run it with the ticking noise.<br /><br />Thanks again.

 

[Boatist]

Re: Steam

Dock<br />I agree with Trent. Probably have low compression on Number 8 because Manifold or Rises bad and allow water into the exhaust valve and cylinder. Exhaust valve rusted to point will not seal.<br />Compression check will tell for sure. Have you ever replaced the manifolds and risers??

 

[boatdock]

Re: Steam

Risers and Manifolds are original, i have not changed them, is it hard?

 

[Fouled Plug]

Re: Steam

Replacement isn't technically difficult, but working with corroded fasteners is never fun. If they aren't too far gone, risers can sometimes be soaked in a muriatic acid solution and rodded out. If they are the original 15 year old units and have seen mostly salt, they may well be toast. The flappers are very important parts...they prevent water from backing up into the engine. Cheap insurance. (Though I've never had anything related to boat ownership be cheap!)

 

[Boatist]

Re: Steam

Dock<br />Replacement of risers and manifold is not hard but first need to find out why you have no compression and fix that problem.

 

[boatdock]

Re: Steam

Ok , i done a compression check and the reading are (1)140(3)0(5)0(7)140 (2)145(4)110(6)145(8)145.<br /><br />I pulled the heads and manifolds, i found two leaking head gaskets and one chipped valve, i plan on getting a valve job done tomorrow.<br /><br />Question: i found large chunks of rusty metal in the riser outlet hose, it was in the shape of the hose boot. is this part of the riser or is this what is left of the flapper. The manafolds looks great, the risers are not so great.<br /><br />Question: My risers have tiny open holes at the output of the riser seperate from the big outlet hole that the exhaust comes out, is this normal, or is this why water comes out of the exhaust.<br /><br />I would like to Thank all the people out there that take time out of their schedule to answer these boat questions, i am very new to boating , your input is very much appreciated.

 

[Trent]

Re: Steam

Number 6 is your "shutter" (flapper if you want to call it that) You said in your first post and I missed it. 1989 5.4L. You shure its not a 5.0 or a 5.7?? Look down the "y" pipe and look for the "shutter" an see if its intact. Replace the "risers" and have the manafolds pressure checked or replace them. My bet is you did not have leaking head gaskets. The risers when out. Main cause of the problem you got.<br /><br />

 

[boatdock]

Re: Steam

you are right it's a 5.7, my water flappers are still there, do they supose to have rubber around edges or should they be just metal. my compression test indicated leaky head gaskets. no compression on #3 and #5 and low compression on #6. exhaust manifolds tested out fine,(they look like they maybe newer than expected). i should get all the various parts back next week for reassembly. hopefully the tapping noise was the pieces from the risers hiting the flapper.

 

[boatdock]

Re: Steam

PS trent thanks for the picture.

 

[Trent]

Re: Steam

Remember when you start it that shutters will tap or make a clicking noise. Maybe your just listening real close now that you have a problem. Common at certain speeds to hear them.