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Cracked Head or oil cooler?

L

lovestotroll

Member
Hello, we are dealing with an 89 VP AQ151c. After changing the oil, we noticed antifreeze coming out outdrive onto cement. Also, when we looked into Heat exchanger, it was empty. Noticed antifreeze laying on top of new oil. As we uderstand, the coolant doesn’t come in contact with the oil unless there is a breach in the system. Either or O ring, gasket or something. Can someone help me narrow this investigation? If it was a crack in block, why would it show up when engine hasn’t been ran since before oil change and a day after oil change, we notice it coming out outdrive? Is there a way to test the oil cooler for leaks?
 
Not really my area on outboard as cooling system is a bit different than outboard and automotive (to some degree). a cylinder leak tester / or compression test would help narrow down if you have a crack head or not. Harbor freight or amazon can find some cheap tooling, just to narrow down what and where. One of the other for tooling wise as the leak tester would mostly check for cracked heads / head gasket, and compression test is how strong each cylinder is, both do about the same but up to you.

now the exchanger is out of my knowledge, and someone here might be able to guide you more on that.
 
It would probably be easier to test the oil cooler off the engine... A conventional radiator pressure tester available at any auto supply store
can be used. The pressure rating on the cap should be observed, This test usually done with a hot engine however in this case, I'd
run the test cold.
 
Thank you Capt Bob! Will report after it’s tested. Just can’t figure why antifreeze would leak out of intake on outdrive when boat hadn’t been started in 2weeks.
 
Depending on heat exchange design.. leak in one or more tubes, defective gasket that isolates FW from raw water side.... on some designs it's on the end caps.
 
sandkicker said:
Depending on heat exchange design.. leak in one or more tubes, defective gasket that isolates FW from raw water side.... on some designs it's on the end caps.
Click to expand...
Hey Capt Bob, after pressure testing heat exchanger, the antifreeze leaked and drained out outdrive. After closer inspection, there never was antifreeze laying on new oil. We have not started this because we don’t want it to overheat but now not sure if it is a gasket on exchanger or the core. This was pressure tested with cold engine. If this is the core, we are in trouble. Cannot find one online anywhere except for a new one over $1500! Thank you for your help!
 
When we took the core off to take to radiator shop as you suggested, we found one of the sealing gaskets on it was turned inward, the isolation rubber pad was all wrinkled and no O rings on either side. So we are keeping out finders crossed and going to replace the main gasket, the two seal ring gaskets and two O rings and see how she does after.
 
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