rebuild or replace and from were

[badbowtie]

I have a 85 mercruiser alpha one that I replaced the outdive last spring. It has been running bad most of the year last yearr but keep using it. Well needles to say I decided to pull it up in the garage and get a idea what is up with the motor. I bought the boat 6 years ago and was told the motor was just rebuilt but had no proof go figure. I tested only 6 out of the 8 cylinders and had 4 good and had 2 with 42 and 52 percent leak down doing a leak down test. I am thinking about just buying a 1985 5.7 from rapido marine like many others have. I decided to look around on BBB and they have a D- score not to good there. But can get one shipped to my door and no core for 1550.00. Made a couple calls today and will have close in it after I have machine work done and buy a rebuild kit. Is there anywere else that has really good deals around the cincinnati ohio area that sells them.

 

[Bondo]

Re: rebuild or replace

Re: rebuild or replace

I tested only 6 out of the 8 cylinders and had 4 good and had 3 with 42 and 52 percent leak down doing a leak down test.

Ayuh,... A halfazzed diagnostic tune-up isn't what I'd base my decision on,...

What are the compression #s,..??
Where was it loosing air in the leakdown test,..??
Are ya Sure it's the Rings,..??
Or could it be the Valves,..??

Either way,.... I'd update to Vortec heads, 'n a 4bbl. manifold....

 

[Alpheus]

Re: rebuild or replace

Re: rebuild or replace

I tested only 6 out of the 8 cylinders and had 4 good and had 3 with 42 and 52 percent leak down doing a leak down test

When you did the leakdown, where was the air escaping from? Valves or rings???

 

[badbowtie]

Re: rebuild or replace

Re: rebuild or replace

I should of been more specific on the leakdown test. Number 5 cylinder was leaking out the exhaust so I figured okay when I do heads fix that problem and then I went two number 7 and had air coming out the exhaust and I also had air coming out the oil fill cap in the valve cover and could hear air coming out the oil dipstick tube when you put your finger over it. I also have a good edelbrock 4bbl manifold already on the motor. As long as I don't switch to vortec heads.

 

[badbowtie]

Re: rebuild or replace and from were

So with the rest of the information what you guys think?

 

[Black as]

Re: rebuild or replace and from were

Replace it !