Hey fellas,
So the 305 in my friends boat is junk (see 77 mercruiser milky oil thread). We have purchased a '78 350, carb to pan, that we want to place in the boat. It is still sitting in the CAR and we have heard it run, checked the oil pressure, pressure checked the cooling system, and all is good. Should be a fairly straightforward swap since both engines are of the same vintage. Now for the questions:
1) The donor engine has a Holley non-marine 4bbl carb and steel GM intake. We ARE (please no posts regarding driveability problems and the like) going to use this since niether of us have time or money to spend on another 2bbl intake (old one is shot) and carb rebuild. Will I run into any issues with the linkage? I know the Holleys are pretty easy to hook up usually, in cars, but the shift/throttle linkage in a boat is more sophisticated and any helpful advice on getting it to all work together would be appreciated.
2) This boat will never see saltwater while under it's current ownership. So I'm not too worried about the core plugs. But I am slightly concerned about the head gaskets. Should we disassemble a perfectly good running engine to replace them with marine grade gaskets, or, more to the point, CAN we leave the gaskets as is and expect them to live a while?
3) I will be swapping the oil pans, I think. We dont have the broken 305 out yet, but if the pans are the same shape (I know they hold the same amount of fluid), can I leave the donor pan on the donor engine?
4) Camshaft. This one has me most concerned. There is a lot of information (all of it true, of course) out on the 'net regarding the differences between marine and auto camshaft selection. I need to restate that we DO NOT have a lot of money (or time) to finish this project. Will the stock 350 cam be ok in this installation? I mean, can he use the boat for a season or two and then swap cams as he saves money for the necessary parts? The stock 898 cam is in good shape on the broken 305, and I have read several posts right here on this forum that state the MCM 260 uses the GM 305 cam. Do we NEED to swap cams (with the expense of new lifters, or course) to give him a decent running, reliable boat to enjoy?
Thanks to everyone for the help on this and my other threads. This place is great!
-Tommy
So the 305 in my friends boat is junk (see 77 mercruiser milky oil thread). We have purchased a '78 350, carb to pan, that we want to place in the boat. It is still sitting in the CAR and we have heard it run, checked the oil pressure, pressure checked the cooling system, and all is good. Should be a fairly straightforward swap since both engines are of the same vintage. Now for the questions:
1) The donor engine has a Holley non-marine 4bbl carb and steel GM intake. We ARE (please no posts regarding driveability problems and the like) going to use this since niether of us have time or money to spend on another 2bbl intake (old one is shot) and carb rebuild. Will I run into any issues with the linkage? I know the Holleys are pretty easy to hook up usually, in cars, but the shift/throttle linkage in a boat is more sophisticated and any helpful advice on getting it to all work together would be appreciated.
2) This boat will never see saltwater while under it's current ownership. So I'm not too worried about the core plugs. But I am slightly concerned about the head gaskets. Should we disassemble a perfectly good running engine to replace them with marine grade gaskets, or, more to the point, CAN we leave the gaskets as is and expect them to live a while?
3) I will be swapping the oil pans, I think. We dont have the broken 305 out yet, but if the pans are the same shape (I know they hold the same amount of fluid), can I leave the donor pan on the donor engine?
4) Camshaft. This one has me most concerned. There is a lot of information (all of it true, of course) out on the 'net regarding the differences between marine and auto camshaft selection. I need to restate that we DO NOT have a lot of money (or time) to finish this project. Will the stock 350 cam be ok in this installation? I mean, can he use the boat for a season or two and then swap cams as he saves money for the necessary parts? The stock 898 cam is in good shape on the broken 305, and I have read several posts right here on this forum that state the MCM 260 uses the GM 305 cam. Do we NEED to swap cams (with the expense of new lifters, or course) to give him a decent running, reliable boat to enjoy?
Thanks to everyone for the help on this and my other threads. This place is great!
-Tommy
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