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1979 305 chevy rebuild or replace?

84Ed

New member
Hello to all. This is my first post and I need some help. I have a 1979 Century 3000 with a 228 mercruiser that needs rebuilt. I have pulled the engine and am trying to decide if rebuilding this 305 is the best idea. I have read that the 305 is a poor cousin to the 350 and that rebuilding a 305 is a mistake.

What do you think?

If I rebuild, I will have a local machine shop do the machine work, heads etc. and I will reassemble. If I do this, do you recommend any special pistons, cam, double timing chain, oversize oil pumps etc. that would be worthwhile?

thanks in advance for any help!

Ed
 
Re: 305 chevy rebuild or replace?

Ayuh,... Rebuild long block 350s can be found for $1500. or so....

You'll spend more than that, 'n end up with an inferior motor doin' up the 305....

Mistake is the nicest word I can think of to describe the idea.....
 
Re: 305 chevy rebuild or replace?

Bondo, why do you say that "mistake". local machine shop pro wants $1250 to put reman crank, new main bearings, new cam bearings, oil pump, timing set, lifters, valve job, gaskets, pistons installed on rods: I would put the crank in, cam, lifters, pushrods, etc. into my original 305.....is it a bad engine compared to a 350, or is just the 45 extra cubic inches that much better?

Ed
 
Re: 305 chevy rebuild or replace?

Bondo, why do you say that "mistake". local machine shop pro wants $1250 to put reman crank, new main bearings, new cam bearings, oil pump, timing set, lifters, valve job, gaskets, pistons installed on rods: I would put the crank in, cam, lifters, pushrods, etc. into my original 305.....is it a bad engine compared to a 350, or is just the 45 extra cubic inches that much better?

Ed

Ayuh,... For another couple hundred bucks, the work is done, just swap the accessories, 'n install, Go Boatin'...
is it a bad engine compared to a 350, or is just the 45 extra cubic inches that much better?

It's a FREE 45cid, 'n the Horsepower/ Torque that comes with it...
 
Re: 305 chevy rebuild or replace?

I get the point.....free works. Ok. where would you get a reman. engine?

thanks.....
 
Re: 305 chevy rebuild or replace?

by the way, if I am going to shop a rebuilt 350, would you recommend any performance enhancements?

thanks again

Ed
 
Re: 305 chevy rebuild or replace?

by the way, if I am going to shop a rebuilt 350, would you recommend any performance enhancements?

Ayuh,... A 350/ 4bbl. is 260hp, over your 228hp, Original hp....

How much ya Want,..?? It comes down to Dollar$ after the initial move...
 
Re: 305 chevy rebuild or replace?

do you have any experience with US Engine Inc. They have a 350 with 300hp that with their winter discount of $200 is $1900 7yr 500hr warranty.

and just to make your point.....where they list for the 305 reman engine, instead of a price it says replace with 350....

link to there web site:

http://www.usengine.us/marine.html
 
Re: 305 chevy rebuild or replace?

Look on craigslist, they have plenty to offer.

I have seen complete 350's with all accessories for $1500.

WHat you need is a LONG block and swap all your stuff if you go with a remanufactured from a reliable source.

to ask someone here what is a good source is like asking what beer do you like best.........too many possibilities.........just sayin.......


Do a google search for your area for marine remanufactured engines.

I did one a few years ago for a 1996 20 ft inboard ski boat, Motor was 350 vortec roller cam and was $1695 delivered and they took the old core.....I just swapped all accessories and was done. ONE DAYS WORK!! No messing with engine rebiulding. Leave that to the PRO'S...

Boat ran like a raped ape!!
 
Re: 305 chevy rebuild or replace?

While all these points are true about swapping, I recommend that you take more than one day to do it. Specifically in the area of the paint. Usual SOP from these places it to do a quick spray with some random unknown cheap enamel. All they care about with the paint is appearance. You, Mr Boat Owner, on the other hand want the paint to be a rust barrier and protectant for your engine. Before you go to all the trouble of installing the accessories I submit that you take time to put at least two coats of POR-15 Engine Enamel on all the parts; block, exhaust, manifold, etc. This paint is not like hardware store enamel. It has lots of solids and enough body so that it doesn't drip and run when you brush it on. I use this on every engine I have ever put in a boat and it lasts and lasts. This is important for two reasons...one, you will never see rusting on your engine when it has been painted properly, and two, when it comes time to sell the prospective buyers will be impressed by a pretty engine over a rusted lump every time...you'll get more dough.

The one other thing to be watchful of is shipping costs. One vendor may be cheap up front but the freight may be 50% more than the other guy.
 
Re: 305 chevy rebuild or replace?

can buy a new 350 crate from GM for what these rebuilders want.

You forfeit the warranty putting it in marine app though.... but it's a brand new motor
 
You forfeit the warranty also if a marine engine and not installed bye a certified mechanic. Say it's a merc then the shop must be a merc certified shop.

Here are a few options as i see it.

What Hy said would be my first choice. Also to add to his post i would go with new mani's risers, and keep your starter and alt. 500-600 for the mani's risers and all the gaskets in one box. Many sites have that package. Then you would be good to go for at least 5 years before you have to pull risers. In fresh water many years more then that.

Buy a rebuild, use your stuff, who knows how long the used stuff will last.

Buy a good running 350 out of a truck they are now in junkyards by the 100's, and you could i guess get a good running one for 500-800, change out the casting plugs use marine gaskets if you boat in salt and use your old stuff. This option will get you on the water the cheapest.

Shop around for a good running marine 350 used in fresh water and just drop it in. Who knows with this option also.

My question is why the motor you have is no good it blow ? Got water in the oil, no compression what ???

I came back to edit the post, you asked about the oil pump, do not use a hv pump a standard pump is more then enough. This is not a race car, race car mechanics are great for race cars.

You don't want to suck the pan dry. Marine engines are different. Single chain is good also.

This boat has what drive ?

See we need that info, cause how many poinies we recommend depends on what the drive can handle.
 
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I'd recommend that you custom build a 5.7L and get away from the fully dished pistons.
Start with an automotive core that has NOT been raw water cooled.
With the correct Q/E (quench effect) piston (for the cylinder head chamber size), you'll still have the desireable Marine C/R!
Any good machine shop staff can help you with your selections.
Cost increase is minimal, and you'll end up with a better suited Marine SBC.

.
 
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84 ED

Where do you live?

That would help to know this so someone may be able to point you in the right direction...........
 
I had a 1979 Century 200 with a 228. Great motor, I got 3000 fresh water hours out of mine without getting into it. But I would replace it with a 350.
 
Theres nothing wrong with rebuilding the 305, as long as the bores are OK, block rust OK, and it requires only an inexpensive hone.

Dont assume a re-build requires lots of machining. this is a boat, not a NASCAR.

305s' just as good as 350s' (except for the extra cubes of course....)

Re-use the old pistons, get a new time chain and gears, can usually re use cam and lifters. Get the heads done of course. you save a ton of cash, although it is a lot of work.

Ive done many sucessfull Hone, Rings and bearings only rebuilds, with great success.

If the 305 requires a re-bore, thats different. Cost of new pistons etc tip the scales in favour of the options everyone suggested re 350 upgrade.

No matter what you do, like others suggest, corrosion prevention, good paint job, lotsa anti seize lubricants IS A MUST!

Just my 2 cents worth...Mark. (still alive)
 
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