OMC loud Clunking

[cowlotter]

with the drive off, you have half the work to pull the motor done. disconnect the cables, exhaust, fuel lines, remove the front motor mount bolts and transom shield bolts and lift the motor out. maybe a 30 minute process

any 1986-1995 5.7 from a truck out of a pull-a-part salvage yard would work. just change the core plugs for brass, and use marine head gaskets. you can be back on the water for under $500

or have your motor rebuilt and be back on the water for about $1700

what do you think could be brokem? rod bearing or something?

[Scott Danforth]

without pulling it apart, its a guess

could be valve train, could be broken piston, could be bearings.

either way, your motor is coming out.

[cowlotter]

without pulling it apart, its a guess

could be valve train, could be broken piston, could be bearings.

either way, your motor is coming out.

what do you think about something like this? ill keep the truck block in mind, i dont think i want to rebuild the current one. its was a jasper rebuilt in 2012 and its already needing another. on this new half package though from michigan motorz what do you think? currently the onlly brand new parts on current engine are the fuel pump risers manifold and starter. which it looks like i could use those on this.

[cowlotter]

[Scott Danforth]

You can build a brand new stroker motor for $4200. However its your money

[cowlotter]

You can build a brand new stroker motor for $4200. However its your money

i just mainly want something reliable and i dont personally build any of the engine or have tools to install it. i can put on the manifolds and other minor parts no problem, thats why i was considering the silver package from Michigan motorz. whats the deal with building a stroker engine vs just having this one shipped in the have the mechanic drop it in? if i decided to do the stroker what conversions would i need with my current 87 5.7 omc setup or do all parts just transfer and engine drops in and go? what brand of engine should i be looking at as well?

[Scott Danforth]

starting from scratch and buying new parts, a 5.7 and 6.2 are the exact same cost. the dimensions of the engines are the exact same.

your dealing with a small block chevy with OMC stuff bolted to it. your replacement motor will be a SBC with your existing OMC stuff bolted to it.

not sure by what you mean brand..... because the brand is General Motors, and you are dealing with the corporate marine motor which is a SBC.

the 315 hp is the flywheel hp for a 260hp motor/drive package

going to a vortec motor is vortec heads and a roller crank.

reliability is purely a function of maintenance.

[cowlotter]

starting from scratch and buying new parts, a 5.7 and 6.2 are the exact same cost. the dimensions of the engines are the exact same.

your dealing with a small block chevy with OMC stuff bolted to it. your replacement motor will be a SBC with your existing OMC stuff bolted to it.

not sure by what you mean brand..... because the brand is General Motors, and you are dealing with the corporate marine motor which is a SBC.

the 315 hp is the flywheel hp for a 260hp motor/drive package

going to a vortec motor is vortec heads and a roller crank.

reliability is purely a function of maintenance.

basically by brand i mean who would i buy a new 6.3 383 stroker from thats marine rated and a direct replacement for the 87 omc. i see a couple remaned ones on ebay linked here, what do you think.

1 - https://www.ebay.com/itm/Reman-6-2L-...OIAAOSwqVBZZNY D

2 - https://www.ebay.com/itm/383CI-Strok...kAAOSwrXVde5pY

3 - https://www.ebay.com/itm/ATK-Chevy-3...wAAOSwKt5ZlxGq

[Scott Danforth]

No, I would buy a brand new virgin block and build a 377. a 383 is a 0.030" overbore in addition to the 3.75" stroke crank

read this (in its entirety) https://forums.iboats.com/forum/engi...-a-383-stroker

there are GMPP links, etc.

a new 377 is $4200, a reman stroker from someone not price-gouging would be about $3k talk to your local machine shop

I built my 468 for less than $3k

[cowlotter]

No, I would buy a brand new virgin block and build a 377. a 383 is a 0.030" overbore in addition to the 3.75" stroke crank

read this (in its entirety) https://forums.iboats.com/forum/engi...-a-383-stroker

there are GMPP links, etc.

a new 377 is $4200, a reman stroker from someone not price-gouging would be about $3k talk to your local machine shop

I built my 468 for less than $3k

sounds good so i was reading here and it says to repower the 87 it might need new parts. will i need a new intake manifold, electric fuel pump? also will my current power steering pump and other belt pulleys hook right up to this 6.2 from center state? also u stated in the other forum about the intake manifold and a 715cfm carb hooked up, u also mentioned new mainfolds for the exhaust. i believe i have a 600 holley and i have brand new exhaust manifolds and risers for my current 5.7. would i need a upgraded carb and get new exhaust manifolds aswell?
http://vi.vipr.ebaydesc.com/ws/eBayI...rsion=d04531b9

[Scott Danforth]

yes, vortec heads have different bolt pattern for the intake
vortec blocks (unless you go GMPP block) do not have a mechanical fuel pump pad that is machined

your exhaust manifolds will bolt to any SBC (from 1954 to today)

600 CFM is a bit small for a stroker

[cowlotter]

yes, vortec heads have different bolt pattern for the intake
vortec blocks (unless you go GMPP block) do not have a mechanical fuel pump pad that is machined

your exhaust manifolds will bolt to any SBC (from 1954 to today)

600 CFM is a bit small for a stroker

so just a new intake manifold, fuel pump and carburetor if i did the conversion? the old belt pulleys will bolt right up with my old power steering to and is there any other new parts id need?

[Scott Danforth]

keep it a 5.7 and your 600 CFM would be fine

[cowlotter]

keep it a 5.7 and your 600 CFM would be fine

the easiest way say is grab this , http://centerstateengine.com/new-mar...-1996-present/ , throw all my current parts on it and call it a day except a new intake manifold since its vortec? or would i have to do the 87 - 96 pre vortec block and no intake manifold?

[cowlotter]

without pulling it apart, its a guess

could be valve train, could be broken piston, could be bearings.

either way, your motor is coming out.

since ill probably be replacing the motor but i cant until next spring would i be fine not changing engine oil or filter during winterizing this season and just treat gas, fuel filter and drain water and call it a day. im trying to avoid spending money on something im going to replace anyways. what are your thoughts?