'78 Ericson27 Atomic 4 Universal Overheating

[CajunSpike]

Have ya'll watched his video?
Even sitting at the dock, the faster he runs the motor the less water flow he gets from the exhaust.

Thats not normal.

Dead idle puts out a lot of water.
But speed it up and the flow goes down to a trickle comparatively speaking.

[JOHN COOKSON]

I agree with Bill. The water flow is defiantly not normal. There should be more water out the back of the boat at higher RPMs.
Right from post #1 the thing I noticed the most is the intermittent nature of the water flow and the resulting overheating. I'm still of the opinion that something in the cooling system is acting as a sort of flapper valve and is letting water flow\not flow which is resulting in overhearing. The thing that appears to be closing the "flapper valve" is increased water flow through the cooling system. It look like you are going to have to keep after it until you find the blockage. If the restriction is after the water pump city water pressure city water pressure will probably be your best course of action.
Sorry I can't be more specific. Keep at it. You'll win in the end.
Aren't boats fun? It's like a marriage. There are good times and bad times.

TRUE GRIT

[chrisoelder]

@JOHN COOKSON

I performed an acid bath last weekend and got a lot of crud out of the engine. I also back washed it with about 20 gallons of water at city water pressure. A lot of debris was coming out that way.

I also have hooked up the cooling hose to the city water pressure and ran the engine, at your suggestion. A LOT of water comes out and the pressure is high enough that I noticed my exhaust manifold inlet was starting to drip a bit. At first, I thought it was just to much pressure between the city water pressure and the impeller pulling water. Could this be my sign that there is a "flapper" causing a blockage still in my exhaust manifold?

Boats are a lot of fun! Even with these issues, I have been able to take her out and have had a blast! Also, I bought this boat knowing she is old but that if I am patient and determined I can make her purr for many more years. Plus taking on this hands-on approach has allowed me to learn SO MUCH very quickly. Honestly, I owe you all a lot - thank you for giving me the confidence and knowledge to fix my own issues.

[CajunSpike]

Is there ANY chance the water pump intake line is collapsing under the pump suction?

As the pump sucks more, if the water intake line is old, it may be collapsing in on itself blocking the water flow as the pump speeds up and releasing pressure
as it slows down. This would have a valve effect.

Can you have somebody throttle the engine while YOU watch the pump intake lines for deformation?

It may also be slightly possible the exhaust pressure of a higher rpm is causing a flap of material to come off the exhaust tube interior lining and make a
temporary blockage.

I'd closely check both the intake water line and the output exhaust line for weakness/separation.

Not sure if its very useful but here's my E27 the first time I got it running consistently, for exhaust flow comparison(no speedup).

http://cajun.dyndns.org:81/seeker/running.avi

[chrisoelder]

@CajunSpike

That is very possible, the lines seem to be old and not have a lot of strength left to them. I am going to have to check that out, it is another great solution to this issue. It also makes sense to how it gurgles at the thru hull. When checking the lines I am going to look for leaks, pinches, and any excessive wear. I may just end up replacing the lines on the engine either way. It wont cost much to pick up hose and screw clamps from home depot

Is there any way it could be an issue with the exhaust?

The only thing that I cant make sense is when I was idling in the bay and it overheated. I was moving pretty quick but that could have been because of the valve being open.

[CajunSpike]

Overheat is nothing more than not enough water making it thru the engine consistently.
Whats blocking it from running thru freely is the mystery here.

I guess if you wanted to:

You could bypass the intake water line by removing it from the thruhull or disconnecting it from the water pump input. Then connect up a bypass hose and somehow extend the hose so you could drop it in a bucket or toss the end overboard to pickup water.
This would test if the thruhull is partially blocked and/or if the intake tube is good. Good flow by getting water another way, is a clue.

You could also bypass the exhaust output line and toss that bypass hose overboard or in the cockpit. If you still get good flow at higher rpm with the exhaust bypass, then the exhaust hose is not the issue.

Process of elimination.

[chrisoelder]

You could bypass the intake water line by removing it from the thruhull or disconnecting it from the water pump input. Then connect up a bypass hose and somehow extend the hose so you could drop it in a bucket or toss the end overboard to pickup water.
This would test if the thruhull is partially blocked and/or if the intake tube is good. Good flow by getting water another way, is a clue.

You could also bypass the exhaust output line and toss that bypass hose overboard or in the cockpit. If you still get good flow at higher rpm with the exhaust bypass, then the exhaust hose is not the issue.

Thats a really good idea, I am going to have to test that. I am going to head down to the boat tomorrow evening. I will try the hose collapsing theory and play with the bypasses. With the bypasses I will run the water from buckets so I can measure how much is being pulled or pushed out.

Thank you for sending the video over! Gives me a good idea of how my water should be flowing. After I get this worked out i need to fix my engine temp gauge

Thanks again! This is really clever

[JOHN COOKSON]

You could bypass the intake water line by removing it from the thruhull or disconnecting it from the water pump input. Then connect up a bypass hose and somehow extend the hose so you could drop it in a bucket or toss the end overboard to pickup water.
This would test if the thruhull is partially blocked and/or if the intake tube is good. Good flow by getting water another way, is a clue.
You could also bypass the exhaust output line and toss that bypass hose overboard or in the cockpit. If you still get good flow at higher rpm with the exhaust bypass, then the exhaust hose is not the issue.
Process of elimination.

This is what I call divided and conquer. Work on one section of the system at a time, be sure it is working correctly then move on to the next section. For me it is helpful to start at one end (the water inlet or the water outlet end) and work to the other end. It results in less scattered thinking. This having been said others have other valid approaches to trouble shooting.

TRUE GRIT

[edwardc]

... It wont cost much to pick up hose and screw clamps from home depot ...

If you do this, be sure to take a magnet with you to test the clamp's screw. Often, hardware store "stainless" clamps will have a mild steel screw which will corrode and jam or fail. Nothing on the clamp should stick to a magnet.

[Antibes]

I think Marine clamps are one of those must do. Hose clamps failing underway is too scary to save a couple bucks. Remember two clamps per end

[alcodiesel]

"Do other boats have a T bard after the thru-hull?"

Mine does not.

[chrisoelder]

ISSUE FOUND!

Alright. Last night I went down to the boat to diagnose the overheating issue.

@CajunSpike 's Suggestion I ran the engine and started checking the hose for a pinch or any kind of wear. I couldn't find any wear or damage but I did notice something interesting. The pressure on the hoses is very strong until I get to my exhaust manifold outlet.

With that info, I decided to place a bucket under my exhaust to see how much water I was pushing out. After 30 seconds of idling, I was able to collect 1.25in of water in a home depot 5 gal bucket. I figured at a higher RPM I would get 1.75xs the amount of water. After 30 seconds of collecting water at a higher RPM, I was only able to collect 1.25in of water in the bucket.

There was my issue. Either with my exhaust manifold or the hose.

Decided to take both the inlet and outlet off the exhaust manifold and boom there is my issue. Both inlet and outlet were caked with goopy, junk. I guess the acid bath cleaned it up but didn't do the heavy lifting.

Here is an image of the exhaust manifold outlet.

After cleaning both the inlet and the outlet, I did my best to break up/ clean anything left in the manifold. Did a quick rinse with my slip hose (city water pressure) then put her back together.

When I ran her the amount of water being spit out was night and day compared to how it was after the acid bath. @CajunSpike I believe you first suggested this and you were right!

Here is a video of the exhaust after the manifold being cleaned (sorry about the quality, I shot it at 925pm :P )

https://drive.google.com/open?id=1M5Tf2dVlld0-M6EGdPKKyipnBH7CWvJZ

And here is before

https://drive.google.com/open?id=16zglsp7pRmeG57QNFaFobY9AMhiviH3f

The girlfriend and I are planning on taking her out this evening to see how she does in moving water but I am feeling pretty confident that was the source of my issue.

Through this experience, I have learned a TREMENDOUS amount of knowledge about my A4 (and engines in general). Thank you, everyone, for the support!!! I really appreciate it. I owe you all a nice cold beer.

Fingers crossed this evening will go beautifully this evening

[ndutton]

Just to acknowledge Cajun’s contribution, that was in the second post (first reply) in this thread 11 days ago. Something else to be learned here is the quality of advice available on this forum. Following the advice carefully can usually save a lot of time, angst and sometimes money.

Good on ya Chris for finding the blockage.

[CajunSpike]

Now THAT'S a good water flow.



I had JUST fought this same battle except I had even less flow than he did, out of the exhaust.
Was -nearly- totally blocked on the manifold outlet.

So if my suggestion can help somebody else, its definitely worth a try.
Just like to do what the rest of you good people do, and help someone.

[chrisoelder]

Sorry :/

Just to acknowledge Cajun’s contribution, that was in the second post (first reply) in this thread 11 days ago. Something else to be learned here is the quality of advice available on this forum. Following the advice carefully can usually save a lot of time, angst and sometimes money.

Good on ya Chris for finding the blockage.

I'm sorry, I felt like such a dummy last night, I should've done that first and this would have concluded a lot faster. I was under the assumption that the acid wash would have cleaned out most of the blockages. Also with backwashing my exhaust manifold that would have been cleared up.

To my ignorance at the beginning, I was very certain that my issue was the lack of blocking off the thermostat housing.

You are right, the info on here is quite amazing and I am extremely grateful for everyone time, knowledge, and insight. I hope that during tonight's sail I won't overheat and we can close this up.

I really hope this thread will be a great resource for others with similar issues and limited knowledge... like myself.

Thank you again!