4.3L OMC engine swap time

[jpwdesigns]

Re: 4.3L OMC engine swap time

You need to replace the freeze plugs(casting plugs) with brass ones.

Will do

 

[Joshua Nichols]

Re: 4.3L OMC engine swap time

The truck heads should be fine.. Same year and everything...
Here is the issue with the marine head gaskets.. The marine head gaskets are more corrosion resistant..

You can buy a new plug kit for that engine on ebay...

There is a upper gasket kit.. Marine grade sold right here on iboats.. It's not too bad.. Anything you can buy to fix a boat for around a hundred bucks is cheap.. Learning that huh?

I wouldn't use permatext on anything if I could help it...

 

[Joshua Nichols]

Re: 4.3L OMC engine swap time

one was welded.

Well that is so when you bought the boat you wouldn't see water pouring in the engine compartment..
They are cast and bet you anything they was welded like crap.. Snap a picture of the weld... Just replace em..

Since you didn't go vortec.. The osco manifolds are pretty good.. I have a set and after painting.. Look pretty good.. They are a pain to drain, but little in the world is perfect.. American made... I found em on ebay for $799.. Warranty everything.. You gotta be a hunter when you run this OMC stuff..

Goodluck

 

[RiggerMark]

Re: 4.3L OMC engine swap time

good morning jpw,
i'm in the middle of the same swap, but it seemed to me that the main difference between truck and boat was the cam, went all over the net, and it seemed that the cam was the one item ( other than bolt-ons) that needed changed, cause i know that when i looked at that truck motor, the last thing i wanted to do was remove the heads and cam, in for a dime, the marine heads are fine, they seem heavier than the stock, did a visual inspect, then inverted them and filled the jackets with acetone, all good, nice looking heads, going to swap them out, removed marine cam and will swap it also, new timing and hopefully a shakedown cruise on sat, if you go the auto route, keep us posted on performance... Mark

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

good morning jpw,
i'm in the middle of the same swap, but it seemed to me that the main difference between truck and boat was the cam, went all over the net, and it seemed that the cam was the one item ( other than bolt-ons) that needed changed, cause i know that when i looked at that truck motor, the last thing i wanted to do was remove the heads and cam, in for a dime, the marine heads are fine, they seem heavier than the stock, did a visual inspect, then inverted them and filled the jackets with acetone, all good, nice looking heads, going to swap them out, removed marine cam and will swap it also, new timing and hopefully a shakedown cruise on sat, if you go the auto route, keep us posted on performance... Mark

HI Mark, let me know how Saturday goes.

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

The truck heads should be fine.. Same year and everything...
Here is the issue with the marine head gaskets.. The marine head gaskets are more corrosion resistant..

You can buy a new plug kit for that engine on ebay...

There is a upper gasket kit.. Marine grade sold right here on iboats.. It's not too bad.. Anything you can buy to fix a boat for around a hundred bucks is cheap.. Learning that huh?

I wouldn't use permatext on anything if I could help it...

Thanks Joshua. I've not decided yet how far i'm going to take it. Planning to pull the engine on Saturday. Either way I'll post what I end up doing and results.

 

[Joshua Nichols]

Re: 4.3L OMC engine swap time

Hardest part of pulling the engine is finding something tall enough to yank it out with...

GoodLuck

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

Hardest part of pulling the engine is finding something tall enough to yank it out with...

GoodLuck

Got me a 4000lb come-along and engine stand from Harbor Freight. 2 sets of 2 2x12's for rafters in my garage. Going to borrow some chains and a big A piece of lumber from my contractor neighbor to straddle those sets of 1x12's and back the boat in. Should be good to go.

 

[Joshua Nichols]

Re: 4.3L OMC engine swap time

Take some pictures and show us how it goes.. Don't tear up your garage

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

Tearing into the engine and looking for the right small block or salvage.

 

[Joshua Nichols]

Re: 4.3L OMC engine swap time

https://picasaweb.google.com/jpwdesigns/EngineHoist?authuser=0&feat=directlink

Tearing into the engine and looking for the right small block or salvage.

The link doesn't work

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

The link doesn't work

:facepalm:
Sorry, edited.

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

Just spoke with a local machine shop. They are quoting me 370 to rebuild my block using my marine cam, and do my heads (resurface, valve job, check for cracks) for 160 + parts.

Sounds pretty good to me, you?

 

[RiggerMark]

Re: 4.3L OMC engine swap time

evening jp,
sounds like a heck of a deal, i just spent 150 bucks on just gaskets for my 4.3, had the heads checked but nothing done to them, heck, i had 200 bucks into the truck block i used, ( the block, pistons, rods, and oil pump is all i used from the truck) not even counting the amazing amount of time to do the job right, ( my shakedown was today, ran better than i hoped 50 mph @4300 rpms, i thought that was cool) i did hate using the different cam bearings, i hope it was all wearing the same..lol if it gets me thru the rest of the season, may do a real rebuild this winter, anywho, didn't mean to hijack your thread, but misery loves company, try to enjoy your build, gets a bit long and kinda costly, but we also save a great bit and i know my boat like nobody ever has.... peace, Mark

 

[Joshua Nichols]

Re: 4.3L OMC engine swap time

That's a cute little engine isn't it? Looks big till ya tear all the goodies off..
We are pretty sure you have a cracked block at this point.. Remember.. You tested it...
See if the shop has a known good block you can buy(Needs to be around the same year.. You can look up GM 4.3 and find out what will work).. They are pretty common and people drop em off and leave stuff all the time( I scored some cheap heads for a diesel this is way).. You might get a good deal..
The heads... Well if your heads are good.. You can buy a short block then.. That is a good way to save a dime.. I guess

You are not going to be able to rebuild a cracked block... It is as good as junk at the recycle yard..

WOW... That is one hella beam you got there....

 

[bruceb58]

Re: 4.3L OMC engine swap time

I thought he found a new block back at post 17.

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

50 mph @4300 rpms

NICE! Good job Mark! I would be thrilled at that result.

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

That's a cute little engine isn't it? Looks big till ya tear all the goodies off..
We are pretty sure you have a cracked block at this point.. Remember.. You tested it...
See if the shop has a known good block you can buy(Needs to be around the same year.. You can look up GM 4.3 and find out what will work).. They are pretty common and people drop em off and leave stuff all the time( I scored some cheap heads for a diesel this is way).. You might get a good deal..
The heads... Well if your heads are good.. You can buy a short block then.. That is a good way to save a dime.. I guess

You are not going to be able to rebuild a cracked block... It is as good as junk at the recycle yard..

WOW... That is one hella beam you got there....

Yeah not going to rebuild a cracked block. The machine shop is going to use a different block. They quoted me $370 for a short block in exchange for my core. I told them I wanted to reuse my cam and they said no prob, just drop off my cracked block and they'd do the rest.

 

[jpwdesigns]

Re: 4.3L OMC engine swap time

I thought he found a new block back at post 17.

Correct, I did find that engine but I thought it would be better to get a professionally rebuilt block using my marine cam and heads rebuilt for about the same price from a local shop than getting a complete truck engine with 100,000K on the clock and have to do all the tearing into it myself. Someone else recommended local since if I have any questions or problems they are there to help. The machine shop i'm talking to has been here in Dallas for decades and came to me by recommendation.

 

[bruceb58]

Re: 4.3L OMC engine swap time

So why aren't you using that block for the rebuild?