replacing 4.3 merc need insider info

[lilhitman2986]

Ok guy and girls, I am new to this I just got my first boat a 1990 with a 4.3. it is a one piece rear-main seal and I put an electric fuel pump on it. The motor is dead and I am replacing it with a junk yard motor. The first thing I ask is will a 4.3l vortec work with my intake and setup I have now? 2nd is do I need a marine camshaft or do you all think the auto cam will work? I have been told many things about the camshaft. I still have the cam from the original boat motor but having a mechanical fuel pump on it I do not know if it will fit into the block. Im sorry I have worked on many cars but the boat is new to me. I thank you for any help.

TJ

 

[Bondo]

Re: replacing 4.3 merc need insider info

Well,..... The Intake will Not fit the Vortec Heads.....
As for the Cam,.... If the Donor motor comes from a Truck,.... I'd just run it.....
You haven't said what this is Hooking Up to Either,..... That's pretty Handy Info.....

1 possibility is that you could reuse the current Heads on the Donor Motor........

 

[lilhitman2986]

Re: replacing 4.3 merc need insider info

sorry about that its hooked up to an alfa 1.

so the intake wont fit the vortec heads but if i swap the heads it will fit the engine.thats good info.

also the newer vortecs have the balance shaft over the cam... will that get in the way of the intake?

the info is helpful i will save alot of time knowing this thanks

 

[Bondo]

Re: replacing 4.3 merc need insider info

The Balance Shafts started long before the intro of the Vortecs......

And, I'm not Sure about the Non-shaft motors,Vs. the Motors With the Shaft in regards to the Intake,......
I Believe it Doesn't Matter........

 

[bruceb58]

Re: replacing 4.3 merc need insider info

If you have an intake manifold from a non-balance shaft engine and put it on a balance shaft engine, the balance shaft will hit the manifold.

 

[lilhitman2986]

Re: replacing 4.3 merc need insider info

thanks guys for all the information i foung a vortec without bal-shaft and bolted it up and she fired. a good motor swap for under 200.00

thanks

 

[bjcsc]

Re: replacing 4.3 merc need insider info

Wish I could get that much done in 24 hours...

 

[lilhitman2986]

Re: replacing 4.3 merc need insider info

beleave me it was more like 30 hours and it was non stop. i took the boat out today and ran about 30 miles with out a problem. i have got to get new mounts due to the fact that my'n are completly rusted out and i could not get it alined... but the ride was smooth i just wanted to see it run before i put more money into it. being my first i/o i have no idea how it works and its kinda worys me.

 

[bjcsc]

Re: replacing 4.3 merc need insider info

You're doing the right thing by learning it yourself. For every good marine mechanic there are 10 imposters. Even at 30 hours that's darn good. Good job and good luck with the mount replacement. You did well finding iboats - there are real marine mechanics here and they have a lot of patience for those of us still learning...

 

[shelikesit]

Re: replacing 4.3 merc need insider info

damn good job TJ.

smooth, is that what i caught? im 50/50 cut between jealous and happy..........

hit me up one day

dana

 

[tommays]

Re: replacing 4.3 merc need insider info

Nice BUT dont run it without fixing the alignment as you dammage the coupler and be pulling the motor again


Tommays

 

[lilhitman2986]

Re: replacing 4.3 merc need insider info

im working on the alinment ishue at the time. beleave me i dont want to do this again any time soon. it was almost to much work. i now have some water coming into the boat i do not know it it is from the exsaht or what but it is hot water and i need to look into that anyways as i replace the mounts.

i will not tell a lie i spent 2 years as an auto mechanic so i know a thing or two about the process. i just dont know how everything in the boat works.

hey dana i will be giving you a call everytime i head out that way.

TJ