woodenboat01
New member
I have looked through all the posts on the 318 motor overheating problems and have not seen my problem. I have rebuilt the 318 Chrysler motor (pre 1966 model 318 BWR10 that was in a Correct Craft Barricuda) and installed it into a homemade inboard powered boat. The motor runs good - the RH block and head runs cool (105 F) but the LH Block and head runs 180 F).
I have done the following:
1) Rebuilt water pump - It is a double intake / double output Sherwood pump. The front chamber pumps water to RH block to RH head to (RH intake manifold) to LH block to LH head to LH intake manifold then to bypass hoses and thermostat to the exhaust elbows.
The rear water pump chamber sends water to the transmission cooler then to the exhaust water jackets. Both RH and LH water jackets run cool.
2) Took RH and LH heads off to check for any blockages. None found. What I did find which I do not understand was the Head gasket holes for cooling water flow matched up perfectly but the large holes (1/2 inch) in the block and head were constricted by the size of the holes in the gasket (1/8 inch). Both RH and LH head gaskets were like this. I have reordered a new gasket set (holes are still small) and plan on enlarging these holes unless someone tells me that these holes are small for a reason.
3) Took off intake manifold and checked thermostat. Thermostat expanded +1/2 inch when heated up to 190F. The temperature guage when running fluctuates from 120F to 190F constantly. I took the thermostat out and the temperature guage did the same thing.
Has anyone had this problem? Any suggestions would be appreciated!
I have done the following:
1) Rebuilt water pump - It is a double intake / double output Sherwood pump. The front chamber pumps water to RH block to RH head to (RH intake manifold) to LH block to LH head to LH intake manifold then to bypass hoses and thermostat to the exhaust elbows.
The rear water pump chamber sends water to the transmission cooler then to the exhaust water jackets. Both RH and LH water jackets run cool.
2) Took RH and LH heads off to check for any blockages. None found. What I did find which I do not understand was the Head gasket holes for cooling water flow matched up perfectly but the large holes (1/2 inch) in the block and head were constricted by the size of the holes in the gasket (1/8 inch). Both RH and LH head gaskets were like this. I have reordered a new gasket set (holes are still small) and plan on enlarging these holes unless someone tells me that these holes are small for a reason.
3) Took off intake manifold and checked thermostat. Thermostat expanded +1/2 inch when heated up to 190F. The temperature guage when running fluctuates from 120F to 190F constantly. I took the thermostat out and the temperature guage did the same thing.
Has anyone had this problem? Any suggestions would be appreciated!
