Building A Mercruiser 350 Few Questions.

[kenny nunez]

The 2 sizes that I remember were 7/16 “ 20 or 1/2” 20

 

[Scott Danforth]

Crank bolt holes go off the crank being used. Is this a GM crank, SCAT, or other?

 

[jws123]

Found a crank bolt that fits oil pump installed. Now the question is the oil pan I had to use is automotive It has a built in baffle already. Should it keep it or cut it off and use the one from old motor bolts to the end of the rod cap bolts.

 

[Scott Danforth]

Baffles are needed more in a boat than in a car

if you are referring to the windiage tray, use it

 

[jws123]

Baffles are needed more in a boat than in a car

if you are referring to the windiage tray, use it

Im going to upload a pic of the pan I got tomorrow and of the other piece have to use one or the other doesnt fit with both.

 

[jws123]

 

[jws123]

as you can see the pan has some sort of tray built in what one should I use ? It has to be one or the other the one built into pan fits with my dip stick. The other one i would just have to cut a hole in it.

 

[alldodge]

The flat tray is bolted to the mains, so you would also need mains with a stud. Pic in this thread shows similar one installed

Don't need both,

https://www.corvetteforum.com/forum...y-oil-baffle-bolt-locations.html#&gid=1&pid=1

 

[jws123]

The flat tray is bolted to the mains, so you would also need mains with a stud. Pic in this thread shows similar one installed

Don't need both,

https://www.corvetteforum.com/forum...y-oil-baffle-bolt-locations.html#&gid=1&pid=1

I have the studs from the old motor Would i be ok with using whats in the pan? or would you use the one with studs i could cut the one out of the pan.

 

[alldodge]

Not sure, lets see what @Scott Danforth thinks

 

[Bondo]

as you can see the pan has some sort of tray built in what one should I use ? It has to be one or the other the one built into pan fits with my dip stick. The other one i would just have to cut a hole in it.

Ayuh,..... If the pan with the windage tray bolts on without interference, go ahead, 'n use it,....
Either one will get the job done,.....
The idea is to stop the crankshaft from slappin' the oil into foam,....

 

[Scott Danforth]

I prefer the windiage tray over a baffle. My guess is the studs from the center caps are hitting the pan baffle. In that case, just use the baffled pan

 

[jws123]

Ok thanks for the Input hopefully have this thing running shortly.

 

[Scott Danforth]

Ok thanks for the Input hopefully have this thing running shortly.

If you have a new flat tappet cam. Make sure to use proper break in oil (high zinc) and once started, bring to 2000 RPM for 20 minutes to break in the cam

 

[alldodge]

bring to 2000 RPM for 20 minutes to break in the cam

Meaning it needs to be in the water for break in, a hose can not supply that amount

 

[Scott Danforth]

Meaning it needs to be in the water for break in, a hose can not supply that amount

Without the outdrive (on the stand), good pressure (over 80psi) and a 3/4" hose, you can do it. However I would break it in on the water

 

[tank1949]

I am trying to build a 350 for my speed boat the old engine was 100% trash and is gone nothing was salvageble except some small parts. The motor had salt water in it sat for years it was a 1985 merc. I have a auotomotive GM shortblock 1973 first gen? block #3970014 bored 30 over I already installed brass freezeout plugs.

My question is for the camshaft I currently have a flat tappet cam from a mercruiser 305 would that work in a 350? or is it to diffrent I am getting conflicting awnsers if they are the same or if it would be less HP?. I also have a roller cam from a newer mercruiser 350 but from what I gather I would have to use retrofit lifters. The cylinder heads I plan to use are from the newer engine that had a roller cam if that makes any diffrence? Its the only good set of rebuilt heads I have laying around currently.

Make a stroker and get at least 50 more HP and if you add vortex heads maybe 70 more hp. MC Thunderbolt 5 with knock sensor would be better than TB4, as far as you ignition system.;

 

[jws123]

So I got busy took a break from this wound up actually getting a diffrent boat LOL. But back to working on this I am about finish things up and throw the motor back into the boat. But I have a choice of 3 ignitions/Distributors boat came with nothing on it. I know one is for sure from a older 350 and has the older style Distributor but it doesnt look the best. The other 2 I am not sure had them laying around pics below what one should I use.

 

[Bondo]

Ayuh,..... Either of the bottom 2,..... One is 24* advance, 'n the other is 22* advance,....

 

[jws123]

Ok thanks hopefully will be firing this thing up this weekend if put it off way to long ahhaha.