Toasty Merkruzer / Fish Smoker
I go through a lot of engines!!!
I think yours is a 6 cylinder I/O ?
I would take off the outdrive and clean out the cooling passages and replace the water pump or at least the impeller, I am not sure if you have a replaceable plastic impeller housing. $50 kit?
I would clean out all parts of where salt water goes through. I think you said you are fresh water cooled, so your block should not be affected by the uptake of crud. Disconnect all the hoses and drain plugs and maybe replace any pencil zincs (just because everything will be apart). Basically chase all the passages where salt water goes and make sure the sediment is gone.
Manifolds? I don't think they will be a problem unless the boat always overheated under a load at speed.
Now that your salt water stuff is clean, probably a good time to flush the motor and put new water/antifreeze miture.
So much for the cooling system pennance.
Now for the motor - note the stuff that comes out of the salt water passages, is garbage even coming out?
Note the coolant that you change in the motor ... is there any oil in there? Let's hope not. Bad head gasket.
Change your spark plugs. Run the motor, go for a ride. Take them out if stuff feels wierd, do any of the plugs look different? Is one really clean? Let's hope not, Bad head gasket.
Probably better to do up front... do a compression test.
I was wondering how come one of my motors was running badly... I 'did everything' ... then I did a compression test, one cylinder, no compression at all. Dang!! Motor number one!
If you have oil in the coolant, or coolant in the oil, a really different looking spark plug from the others and or low or no compression in a cylinder or two, a head gasket needs replacing, and possibly a head needs to be machined straight. Just exchange the head(s) at that point for a rebuilt one ($150 plus gaskets?).
I am doing motor number two this year (the other side), why not, I now know where all the bodies are buried with the job!
A good source for hard engine parts (heads, blocks, etc) is Rapid O Marine in Florida. www.rapidomarine.com
Good Luck,
vk
I go through a lot of engines!!!
I think yours is a 6 cylinder I/O ?
I would take off the outdrive and clean out the cooling passages and replace the water pump or at least the impeller, I am not sure if you have a replaceable plastic impeller housing. $50 kit?
I would clean out all parts of where salt water goes through. I think you said you are fresh water cooled, so your block should not be affected by the uptake of crud. Disconnect all the hoses and drain plugs and maybe replace any pencil zincs (just because everything will be apart). Basically chase all the passages where salt water goes and make sure the sediment is gone.
Manifolds? I don't think they will be a problem unless the boat always overheated under a load at speed.
Now that your salt water stuff is clean, probably a good time to flush the motor and put new water/antifreeze miture.
So much for the cooling system pennance.
Now for the motor - note the stuff that comes out of the salt water passages, is garbage even coming out?
Note the coolant that you change in the motor ... is there any oil in there? Let's hope not. Bad head gasket.
Change your spark plugs. Run the motor, go for a ride. Take them out if stuff feels wierd, do any of the plugs look different? Is one really clean? Let's hope not, Bad head gasket.
Probably better to do up front... do a compression test.
I was wondering how come one of my motors was running badly... I 'did everything' ... then I did a compression test, one cylinder, no compression at all. Dang!! Motor number one!
If you have oil in the coolant, or coolant in the oil, a really different looking spark plug from the others and or low or no compression in a cylinder or two, a head gasket needs replacing, and possibly a head needs to be machined straight. Just exchange the head(s) at that point for a rebuilt one ($150 plus gaskets?).
I am doing motor number two this year (the other side), why not, I now know where all the bodies are buried with the job!
A good source for hard engine parts (heads, blocks, etc) is Rapid O Marine in Florida. www.rapidomarine.com
Good Luck,
vk
