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Problem with my new engine install

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walldiver7

New member
Just fired up my brand new 4.3 Vortec (Long block) that I installed.
I'm hearing a whistling noise as if there's a vacuum leak... And there's no water going through the block with the muffs on.

I did install a new 2 barrel intake mani ... do I have a leak? How do I test for that? Idle was a bit high, but not rough like I'd expect with an intake leak.

With the old engine, the water flow through the engine was fine. The old engine had no more than 250 hrs on it, thus the drive too.

???
 
Get the waterflow issue solved first befroe you destroy the new engine. Does it need a new impeller? Sounds like it.

"do I have a leak? How do I test for that?" Spray carb cleaner aroung thr carb and intake gaskets.
 
Working on the water problem this morning FIRST. Did a brief run again this morning .. turned up the water pressure to the muffs and did get water running out through the prop, but not at the base of the transom.

Noticed that I had forgotten to screw in the exhaust drain plugs at the connection elbow at the base of the exhaust manifolds. No water was running from them when I did my test.

It's hard to believe that in the later part of April the impeller was fine with the old engine and now, not ok.

I guess it's time to pull the lower unit and take a look at the impeller?

Thank you for your comments/ideas/help!
 
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What year is the boat?

If the OD was off for any length of time it could have taken a "set" that won't allow a good seal in the water pump cavity. It may have broken apart--if it did, find the pieces and back flush from the thermostat fresh water connection.
 
What year is the boat? The hull is a 1999 Bayliner. The new engine is actually a 2009 with the roller rockers.

If the OD was off for any length of time it could have taken a "set" that won't allow a good seal in the water pump cavity. The OD was off for about 35 days wrapped up to keep the dust out.. and layed on it's side. It may have broken apart--if it did, find the pieces and back flush from the thermostat fresh water connection.
I don't have a fresh water connection in any of my hoses.

"Ding!" You know... I may have cause the impeller to fail. I was checking the OD for noises while it was off (I've had a vibration for the past 2 years that I've been unable to track down... even went as far as replacing the gimbal bearing) AND I hand rotated the OD drive shaft.... I think I may have rotated it backwards. I'd bet that this may have broken the impeller.
 
Pulled lower unit. The impeller is fine. Nothing broken, completly intack, and not brittle. Whether it has taken on too much of a "set" is unknown to me. I will replace it since I've gone this far.

The Question remains: Why is water not passing through my new engine? I'll go back and check hoses for kinks and mis-connections.... I did replace the thermostat.... hmmm...
 
Calm down and think along these lines to find the problem.

Remove the hose coming in from the trasom from the heat exchanger or t-stat housing you want to put water to the drive and start the motor and see if good water is coming in from the drive, understand.
 
Closed system or raw water? I assume it's raw water. If you installed the wrong intake or intake gasket you might have blocked off a main cooling passage. Start taking the system apart at the thermostat and see if water is getting to that point. If not, work your way back towards the drive. If so, work your way through the motor but I would suspect the wrong gasket.
 
Water circulation solved

The new impeller, evidently, did the trick ! So, I guess it's safe to say that the "set" of the original impeller was the cause of no water circulation.

Now to the other problem: finding the vacuum leak.

Thanks to all that chimed in on this!
 
Glad to hear it was the problem. Is there a manifold port you can attach a nipple to in order to use a vacuum gauge? It will tell you if it is a vacuum leak or just a noise from a better engine.
 
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