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Mercruiser 4.3 and Chevy/Astro Vortec Block?

T

tintinek19

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Hi everyone as my bottom end have seized I needed to find a solution to rebuild cheaper I've managed to get hold of

4.3 1994 astro block which has balance shaft i didn't check that when i brought it now the problem i think i have is

my 4.3 1994 (non vortec i think) boat block does not have balance shaft and it had mechanical fuel pump.

my question is what are my options here?

thank you,

Mike
 

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Keep all the parts balancer engine etc with the Astro engine, change freeze plugs, head gaskets, circ pump marine. Install a marine electric fuel pump powered through and oil pressure switch.

Thee may be some issues lining up pulleys but should be able to mix and match to get it to work. Would think both are V belt engines not serpentine?
 
tintinek19 said:
Hi thank you for you answer , yes they are v belt. So the balance shaft will not make difference for the manifold intake? Thanks
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Only difference in intake is if one engine has vortec heads with 8 vertical intake bolts. Despite vortec being on the valve covers pre 1996 when the vortec head design came out, neither engine if it is a 1994 will have vortec heads.
 
Thank you again ! , I have checked and my heads of the original engine are not vortec. The donor block is from a vortec engine. Not sure if it had vortec heads.

Thanks
 
tintinek19 said:
Thank you again ! , I have checked and my heads of the original engine are not vortec. The donor block is from a vortec engine. Not sure if it had vortec heads.

Thanks
Click to expand...
As Dieter posted, the intake manifold bolts will be vertical, not at a right angle to the mating surface on the heads. OTOH, a Vortek intake manifold shoudn't be expensive.
 
Dieter said:
Are you swapping long blocks or mixing and matching parts
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I have short block with crankshaft pistons rods etc. from astrovan (vortec).

so what i want to do is put the heads and everything else from my original short block engine that was in bayliner boat and seized
 
tintinek19 said:
I have short block with crankshaft pistons rods etc. from astrovan (vortec).

so what i want to do is put the heads and everything else from my original short block engine that was in bayliner boat and seized
Click to expand...
Should fit would just be careful if valve train is different- pushrod length adjustable vs non adjustable. I'm not saying it will be different just something to look out for

Would also make sure the heads are checked out by a competent machine shop. Once swapped a head on an engine that had rod bearing damage, got a new short block, swapped head over.... it dropped a valve/ valve hit piston and smoked the short block. Was a real money saver vs getting a long block

this thread on Iboats forum goes over some of the generational differences of the 4.3s over the years

complete history of the 4.3 liter with casting numbers

thought I would post the complete history of the 4.3 liter that I could find. These are links and articles that I have bookmarked for my own use, however they should help many people. it may help some people when looking for parts or sourcing a salvage yard motor or a reman. keep in mind that...
forums.iboats.com forums.iboats.com
 
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Dieter said:
Should fit would just be careful if valve train is different- pushrod length adjustable vs non adjustable. I'm not saying it will be different just something to look out for

Would also make sure the heads are checked out by a competent machine shop. Once swapped a head on an engine that had rod bearing damage, got a new short block, swapped head over.... it dropped a valve/ valve hit piston and smoked the short block. Was a real money saver vs getting a long block

this thread on Iboats forum goes over some of the generational differences of the 4.3s over the years

complete history of the 4.3 liter with casting numbers

thought I would post the complete history of the 4.3 liter that I could find. These are links and articles that I have bookmarked for my own use, however they should help many people. it may help some people when looking for parts or sourcing a salvage yard motor or a reman. keep in mind that...
forums.iboats.com forums.iboats.com
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Hi Thanks for you answer again the heads I have are 14094768(non vortec) they fit good on the block so far with all bolts aligned.

The intake manifold does not sit properly because of the balance shaft in the way.

The bulge is hitting on the balance shaft I’ve searched everywhere can find any answers.
 

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If you look at this web site it has a master listing for all engines

I just found this, V6 with balance shaft, Intake without the stamped steel part you reference.

So anything prior to that year does not have the balance shaft If I understand it correctly

Parts for MerCruiser 4.3L (Gen+) (2 Barrel.) GM 262 V-6 1998 Cylinder Block & Camshaft​





Parts for MerCruiser 4.3L (Gen+) (2 Barrel.) GM 262 V-6 1998 Intake Manifold & Front Cover​


Master parts list for balance shaft gen II engines


Master engines and outdrive listings from this site

 
tintinek19 said:
Hi Thanks for you answer again the heads I have are 14094768(non vortec) they fit good on the block so far with all bolts aligned.

The intake manifold does not sit properly because of the balance shaft in the way.

The bulge is hitting on the balance shaft I’ve searched everywhere can find any answers.
Click to expand...
Heads are same bolt pattern vortec or pre vortec.

what is behind the heat shield that is riveted on. I would try to knock rivets out. usually that is only there to keep hot oil off the bottom of the intake.

On edlebrocks site it has a listing for 1985 thru 1995 intake and a vortec which is 96 and up. I'm not suggesting you use the intakes just that that is the split on the fit
 
@kghost thanks for the input , the issue I'm facing here my heads are non vortec (but the replacment block is from vortec engine)therefore I need 12 bolt intake not 8.

@Dieter so removing the shield will solve my problem?, will there be consequences?

Thank You
 
I understand but its not clear that you were understanding what your dealing with. Now I know.

I would hope removing rivits and steel pan will work. Balance shaft appears to deflect oil. I have no personal experience with this swap.
if it works, You will appriciate the balanve shaft engine. Lots smoother running.




tintinek19 said:
@kghost thanks for the input , the issue I'm facing here my heads are non vortec (but the replacment block is from vortec engine)therefore I need 12 bolt intake not 8.

@Dieter so removing the shield will solve my problem?, will there be consequences?

Thank You
Click to expand...
 
tintinek19 said:
@kghost thanks for the input , the issue I'm facing here my heads are non vortec (but the replacment block is from vortec engine)therefore I need 12 bolt intake not 8.

@Dieter so removing the shield will solve my problem?, will there be consequences?

Thank You
Click to expand...
I would think you can take off the shield (should be done for cleaning anyways), and maybe some more hot oil gets on the intake and it is warmer?

I doubt you would be the first one to take off the shield and not put it back on over the last 50 years...

This may be the intake you need but I cant confirm 100%. It says vortec but it does not have 8 vertical bolt holes but the heat shield is flatter may be what you need

https://www.ebay.com/itm/316615520852?_skw=marine+4.3+intake+manifold&itmmeta=01JSCT77SNTJ0A2RXHYDWV659D&hash=item49b7c17254:g:X6QAAOSw1uVn0uAU&itmprp=enc:AQAKAAAA4FkggFvd1GGDu0w3yXCmi1emOOiTUx0DmxdvA9efeWD7NMplmhXmXWFCxc74wxgRcQEjGUK+4tOSnjp2HWQR4g93Xa9K2xll0w9NEoy+jBVT3KhTeWySzc33Pq93tWpF0V6QZowK7u3RdXDa23eY22jpDTbPyQ1kgFAYiwFc2WWAXHt8WiiDMR5NsmspwmYoKoUdfqa7eUCvr9ajrYay8r7ch2+vCUlQvnQ0g4xW9zzgeArIa+/VpDHd9+7SwEa/67pE6WOrkPHIgj42NdViCjaLJ/Jbk+M1gAttYJVEURdy|tkp:Bk9SR4D9nJrLZQ

when ever you get into mixing and matching a certain amount of SWAG is involved. If it were mine I'd knock of the rivets, clean out the crud , see if it bolts up, if it does use it

here is another listing for intake with flatter shield see note about for balance shaft 10 bolt metal timing cover

www.nlamarine.com

MerCruiser 824324 824324T Intake Manifold 4.3L 2BBL 12Bolt 1993-1996 GM 14097289

Part Number(s) Included MerCruiser 824324 / 824324T Intake Manifold 12-Bolt Intake Manifold 2-Barrel For early Pre-Vortec balance shaft engines with the 10-Bolt Metal Timing Cover GM 14097289 Casting Number General Application / Compatibility MerCruiser V6 4.3L / 4.3LX (GEN II) engines with an...
www.nlamarine.com www.nlamarine.com

looks like part numbers are 824324T and 824330T for 2 and 4 bbl intakes respectively. booth are listed without the T then superseded to same P/N wit the T ...
 
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Hi guys i have finally put it together and started it on the pallet!! and it lives, now I'm facing problem with the damper/pulley on the crankshaft the old engine had the 3 grove pulley/damper the replacement block came with car/truck pulley therefore the harmonic balancer is different as well because the auxiliaries on the donor engine were run by serpentine belt. what solutions do i have?

attached image is the damper/pulley i have from old block. the bolts dont reach trough it , even if i use longer bolts it wont align with other auxilaries. the second one is the one that came with the donor engine

thanks!
 

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