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Water in Intake

boatingfun1

boatingfun1

Contributing Member
Hello, i have a 1999 GM 5.7 marine motor, with Indmar intake. Looking for the best gaskets to get. It has a heat exchanger freshwater. Raw water cools the exchanger. I have water when i pulled intake pulled dipstick milky. I have the black rubber gaskets with metal. I did not add silaco e to the water ports.
 
with Fresh water cooling, the gaskets dont need to be made from anything special....you should be able to order them from our host - call the 800 number if you cant find it online...

Sad part is with the intake pulled you can't pressure test the cooling system so the source of the leak is hard to say...so there may be more work ahead...
 
makomark said:
with Fresh water cooling, the gaskets dont need to be made from anything special....you should be able to order them from our host - call the 800 number if you cant find it online...

Sad part is with the intake pulled you can't pressure test the cooling system so the source of the leak is hard to say...so there may be more work ahead...
Click to expand...
What do you suggest i start with?
 
not knowing the history, this is just a crap shoot...you may get lucky with the cause being the intake gasket...so replace it and see what happens...

Hopefully, the milky oil was removed and fresh oil replaced it ...and the filter was changed...and the engine run to dissipate any remaining water inside of the engine...
 
makomark said:
not knowing the history, this is just a crap shoot...you may get lucky with the cause being the intake gasket...so replace it and see what happens...

Hopefully, the milky oil was removed and fresh oil replaced it ...and the filter was changed...and the engine run to dissipate any remaining water inside of the engine...
Click to expand...
Thank you!
 
makomark said:
with Fresh water cooling, the gaskets dont need to be made from anything special....you should be able to order them from our host - call the 800 number if you cant find it online...

Sad part is with the intake pulled you can't pressure test the cooling system so the source of the leak is hard to say...so there may be more work ahead...
Click to expand...
I put the intake on with the old gaskets and Compression test all cyl. at 180 psi. I also went and had to readjust the valve. Watch a good video on recheck valve adjustments. Get tdc then adjust the up and down movement, then half turn. do this every 90 degrees through the firing order. Was having odd compression reading on bank 1 which was the side miss firing. Gonna buy new Intake gaskets. Think put water in and pressure test with new intake gaskets?
 
makomark said:
This is contradictory....

the intake gaskets shouldn't have any impact on the compression test results...
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No but i did find the bank 1 off when i went and readjusted the valves. That bank was misfiring. Will pressure test with old gasket. Should i use silicone around all 4 coolant ports on the heads? Do you think the old gasket will hold ok?
 
not being able to see what you have its hard to say if the old gaskets will work...normally, I'd say replace the gasket set.

The service manual states to apply Locktite PST to the inner manifold bolt threads...and then torque them
 
makomark said:
not being able to see what you have its hard to say if the old gaskets will work...normally, I'd say replace the gasket set.

The service manual states to apply Locktite PST to the inner manifold bolt threads...and then torque them
Click to expand...
 

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makomark said:
not being able to see what you have its hard to say if the old gaskets will work...normally, I'd say replace the gasket set.

The service manual states to apply Locktite PST to the inner manifold bolt threads...and then torque them
Click to expand...
What do you think? Should i get another kind of Intake gasket?
 
i think I would have replaced the gasket set a month ago....I don't think you will have many options regarding the style of gasket available...
 
makomark said:
i think I would have replaced the gasket set a month ago....I don't think you will have many options regarding the style of gasket available...
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Yeah this i rebuild the motor my self. Was a autotech for over 25 years. All new gaskets think i might of screwed the torques on it. Wish i could get more information. I know it a 1999 GM 5.7 closed cooled water heat exchanger. Salt water is what keeps it cool. I see some say the one i have is no good and other said to get the other one. Would like a little guidence.
 
If you are talking about the intake gaskets, with a heat exchanger, then the regular auto gaskets should be acceptable...either way, proper installation is key to getting a good seal...
 
makomark said:
If you are talking about the intake gaskets, with a heat exchanger, then the regular auto gaskets should be acceptable...either way, proper installation is key to getting a good seal...
Click to expand...
Make sure 1/4 thick bead of black rtv, front and back on the block and aaround both coolant ports, correct? Tourque for Aluminum intake 18 ftlbs or inches?
 
makomark said:
If you are talking about the intake gaskets, with a heat exchanger, then the regular auto gaskets should be acceptable...either way, proper installation is key to getting a good seal...
Click to expand...
This correct one? Even if the coolant ports on gasket not totally square?

1999 CHEVROLET TAHOE 5.7L V8 Intake Manifold Gasket | RockAuto

RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Easy to use parts catalog.
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I’m not sure that there are marine gaskets for Vortec engines that are different than auto style gaskets.
The main thing is to make sure the mating surfaces of the intake manifold are flat & level and proper torque specs are used..the torque for them is like 15 ft lbs vs the old pre-Vortec who’s was 30-35 ft lbs.
 
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