Guys I need some input

[shu9265]

I have a Merc Crusier 488 140 hp, 1983 vintage. with an I/O

This is one of the 2 years( I have been told) Merc built there own blocks.

My question is, should I try and rebuild this puppy or put it to rest and buy a new motor? This is the one that has it's own self contained cooling system.

I don't know what I am going to find wrong in there if anything. It's been a great runner, and has brought me home every time we have been out.

I have the motor out and in the garage on a stand now. The reason I pulled it is that once in awhile at high speed, it would back fire for no apparent reason.

So that's where I am , between a rock and a hard place.

Waiting for some input on this Thanks in advance, Bill.

[Mike]

Rebuilding the motor will not correct your backfire.

I don't know what ignition system your engine is equipped with, but it sounds as if you have an intermittent ign system problem.

Shoot me some more details and we will sort it out.

[shu9265]

Mike,

the ignition setup has the old style with points and condenser, and round coil off to one side.

Another reason for wanting to rebuild, it that I am seeing a lot of oil at the breather, (blow by/ back)

[Priority1]

Shu,

Those 488 Mercruisers were used in 83 and 84 only. They are next of kin to the 485 used in yrs 80-82 and the 470 used 76-84. These engines were designed to run with different fuel than todays blends. The original ignition timing was 8 degrees BTDC. Lately a lot of those older Mercruisers have had piston damage especially in the #1 and #4 cylinders. It is recommended to set the ignition timing to 4 degrees BTDC, to avoid damaging the pistons. Premium fuel may help also.

I think basically these older Mercruiser 4s were half of a BIG Block Ford. They were troublesome. These engines are 3.7L or 224CI and had a bit more HP than a 140. I'm not sure what it would cost to repower, but I would spend my dime on that before I rebuild one of those engines. JMHO

Frank:)

[Rayman96]

Give these guys a call and price some different options. Good luck.

http://www.michiganmotorz.com/

[Priority1]

Give these guys a call and price some different options. Good luck.

http://www.michiganmotorz.com/

Good suggestion Ray.

Shu, You may want to check out Michiganmotorz eBay listings also.

[special x]

Shu the high speed back fire is ignition related ......worn dist shaft & bushings.Here is the Serria # for electronic conv 18-5297............The cyl head is a 460 Ford.... Block is Merc design..They are right about the fuel & timing , but if you do a reman with the updated lower comp pistons you can run the new fuel with the 8 degrees of timing. We have overhauled them for about 2500.00 seen them for as high as 5200.00 for a reman.... Water pump end of cam shaft is a critical area they do make a sleeve for it

[shu9265]

Update...

Well I got a rather unpleasant surprise when we took the engine out, after getting it on the engine stand and removing parts, and once we pulled the head, surprise ! there was a crack in the head above #4 cyl.

Well after much thought and debating, I went out and found a mid 70's Lincoln with a good 460 engine in it. After getting this thing home I stripped the heads off found NO cracks ! (yeah !) Now the fun part. I had to mill this head to put a water port into it.

Well after some planning and a bunch of rigging on the mill, we have succeeded in putting a water port connection into this thing ! ! !

First of the week it goes the the shop, where it gets resurfaced, pressure tested, and valves, guides, and seals put in. Then hopefully, my gasket sets will be here and it can go back together.

I love Merc crusier, just don't much care for there idea's. LOL

Anyone need a new head for a 488 ? I just happen to have a spare !