89 5.0 mercruiser

[wellyboy]

Good morning all, I have a 1989 5.0 mercruiser that I am thinking of changing. what are the differences in the years and what years would I be able to use ? thanks so much in advance

 

[NHGuy]

Re: 89 5.0 mercruiser

What are you trying to accomplish? The motors don't wear out or fail usually. But if you are going for more power or speed, sure a 5.7 or a stroked 5.7 will fit right there. If the existing motor doesn't run right, make sure the ignition, fuel system and driveline are correct. That's needed with any motor. And if fixing that stuff gets a big improvement with your existing engine that leaves money saved for enjoying it.
To check your existing engine warm it up on muffs and then do a compression test.

 

[tpenfield]

Re: 89 5.0 mercruiser

Yes, a serial number from the engine would be helpful to know. . .(check for a tag on the flywheel housing near the starter).

Can we assume that this engine was used in salt water, since you are in Long Island? and would the new one be the same? AS NHguy said, what issues are you trying to address?

 

[wellyboy]

Re: 89 5.0 mercruiser

Yes, a serial number from the engine would be helpful to know. . .(check for a tag on the flywheel housing near the starter).

Can we assume that this engine was used in salt water, since you are in Long Island? and would the new one be the same? AS NHguy said, what issues are you trying to address?

In the event that I may have a cracked block, Thanks for the fast response

 

[Scott Danforth]

Re: 89 5.0 mercruiser

the big changes are as follows
Motors build in 1986 and later have the one-piece rear seal (smaller crank hub) and center-bolt valve covers
Motors about 1988/1989 started getting roller cams (this is a transition year)
Motors built about 1994 and later started getting electric fuel pumps (the mechanical pump boss is not machined), and again this is a transition)
Motors built in 1996 and later get the Vortec heads and require a different intake manifold

so depending on what you are replacing on your 1989 motor, I would move to a 1996 or newer motor that is complete. this gets you a roller cam and the vortec heads.

 

[Bondo]

Re: 89 5.0 mercruiser

In the event that I may have a cracked block, Thanks for the fast response

Ayuh,.... I'd be Sure of that, before ya call it junk,...

As noted, Any SBC from 1955 to today can be bolted in,... another '89 bein' the Easiest,...

That said, if yer Right, 'n it's Junk, go for a 5.7l replacement,...
All yer parts will bolt on, 'n work,...