4.3 motor swap with truck engine

nola mike

nola mike

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achris said:
? You have a Gen II block? If so that means it has a balance shaft, so the timing cover and water pump WILL go over to the new block.
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Unless you go with vortec heads
achris said:
Most likely yes.
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As Scott said, the newer blocks use an unholy combination of metric and imperial fasteners. Your starter won't swap over because of this either.

You need to decide if you were going to use vortec heads and a four barrel carb or not. The swap will be a good bit simpler with your current heads and carb. But not nearly as cool.
 
T

timharper89

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Scott Danforth said:
Vortec heads are an honest 20hp because of the chamber shape. Used iron vortec manifolds are $50 or less
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I can seem to find any for $50. Not sure where to look other than Craigslist and fb marketplace..
Scott Danforth said:
PMGR starter is 22# lighter than a direct drive starter, uses half the power and has twice the torque

You use nothing bolted to the truck block and heads. You have to use the marine stuff from your current motor

If you do not have a mechanical fuel pump boss, you may already have a vortec block in the boat. Post casting numbers
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I could not get any visual on casting numbers. I'll pray pictures of what I could see. Intake manifold had a stamp
Scott Danforth said:
How many bolts holding the intake on the busted block? 8 or 12?
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6 on each side, so 12
 

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Scott Danforth

Scott Danforth

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here is a set of heads, intake and carb for $500. should be able to get it for $400 cash
providence.craigslist.org

GM Vortec 4.3 v6 marine Heads Intake Edelbrock Carb - boat parts -...

Marine GM 4.3 Vortec heads with low hrs complete with intake and edelbrock 4 brl carb. $300 OBO Send Text Leave your name and number i will call you back. Brian
providence.craigslist.org

iron 2-barrel marine - offer $50
charlestonwv.craigslist.org

2 BARREL CARB. INTAKE OFF 4.3 CHEVY ENG. - auto parts - by owner -...

PICK UP ONLY TWO BARREL GM STEEL INTAKE PART NO.12552422 CAME OFF MARINE 4.3 VORTEC ENG. PRICE $75.oo IF INTERESTED YOU MUST CALL NO TEXTING NO E MAILING PLEASE NO CALLING AFTER 11PM THANKS AND HAVE...
charlestonwv.craigslist.org

here are some in the $60 range. https://portland.craigslist.org/mlt/pts/d/portland-boat-intake-manifolds/7490512908.html


block casting is on back of engine block, above the flywheel housing flange, behind and below the cylinder head

12 is a non-vortec
 
Scott Danforth

Scott Danforth

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itsathepete said:
Salvage yard. Basically any full size Chevy or GMC pickup or van and some astro vans and S10s from 1996 to 2014 with a V6
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Those are EFI motors. You wont find a vehicle with a carbureted vortec 4.3
 
Scott06

Scott06

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nola mike said:
This confused TF out of me when I started stripping out the holes using nearly identical to M10 ⅜ bolts. Ridiculous.
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Threw me for a loop too - had old engine in air stripping parts to go on new base engine … no fit…. Rigger I use at work was doing me a solid was hoping to be in an out in a couple hours. Luckily he took care of me and came back for install 15 ton crane each time … was working at a brewery at time … ten cases each trip

I’m sure there is a reason that makes Sense in a bean counting corporate way but would like to know what it is
 
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timharper89

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Alright, so I hope I have this right. I am keeping the heads, intake and carb from my old motor due to unavailability of low priced vortec intake and 4bbl carb. I'll hang on to the heads and keep my eyes on the used marketplace in my area. I plan to use the bolts that are different from the donor motor for the starter and plan to, for now, keep the original starter from my current motor (this is kind of a bandaid to get us by until we find the right upgrade for us). The following is a list of things I am purchasing. I understand I may or may not need a new water pump. Any way to tell before I get a new motor? The picture I posted was what I could see of a casting number. "gm 4.3L" is all I could make out. I'll try to get eyes on it again and see what I can find, but there isn't a lot of room to see much else at the moment. There appears there are numbers under it, but they are not legible to me. Any other tools I need to pull a motor from a truck or for this job overall? I assume I will need to set the timing with a timing light? Anything I'm missing/overlooking?
1 of these:
www.summitracing.com

Sierra Marine 18-4319 Sierra Marine Powerhead Gasket Sets | Summit Racing

Free Shipping - Sierra Marine Powerhead Gasket Sets with qualifying orders of $109. Shop Marine Powerhead Gaskets at Summit Racing.
www.summitracing.com www.summitracing.com

8 of these:

2 of these:
www.wholesalemarine.com

Sierra 18-2909 Exhaust Manifold Gasket Replaces 27-99757

Sierra 18-2909 Exhaust Manifold Gaskets are available at Wholesale Marine. We offer Sierra Marine parts at the lowest prices with fast shipping.
www.wholesalemarine.com www.wholesalemarine.com

1 of these:
www.summitracing.com

Sierra Marine 18-2619-1 Sierra Marine Outdrive Gasket Sets | Summit Racing

Free Shipping - Sierra Marine Outdrive Gasket Sets with qualifying orders of $109. Shop Marine Outdrive Gasket and Seals at Summit Racing.
www.summitracing.com www.summitracing.com

an engine alignment tool
 
nola mike

nola mike

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timharper89 said:
plan to, for now, keep the original starter from my current motor
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Like I said, your starter won't work without modification. Definitely not worth it when you can get a PMGR starter for less than $100.
The core plugs might already be brass on the donor--check before replacing.
 
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timharper89

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nola mike said:
Like I said, your starter won't work without modification. Definitely not worth it when you can get a PMGR starter for less than $100.
The core plugs might already be brass on the donor--check before replacing.
Click to expand...
I thought the issue with the starter was just the mounting bolts. I must have misunderstood? What will not work with my starter?
 
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timharper89

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nola mike said:
Like I said, your starter won't work without modification. Definitely not worth it when you can get a PMGR starter for less than $100.
The core plugs might already be brass on the donor--check before replacing.
Click to expand...
What starter will fit on a new vortec block? my current block has no mechanical fuel pump, so it is newer than the original. What do I need to look for with a new starter to make sure it fits?
 
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itsathepete

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timharper89 said:
What starter will fit on a new vortec block? my current block has no mechanical fuel pump, so it is newer than the original. What do I need to look for with a new starter to make sure it fits?
Click to expand...
Just because the block doesn't have a mechanical fuel pump doesn't mean its a vortec gen 2. Get the casting number off the old block or remove the intake and look for a balance shaft. If you do have a balance shaft block, the starter will fit the new engine
 
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