Glad I waited until the teardown

[John_S]

I have a K series serial number 5.7L /alpha genII mercruiser. It is in a '97 2050 Bayliner. As far as I could tell it is a '97 engine. It has the serpentine belts (new in '97), composite timing chain cover, and larger vibration damper of the vortecs. I did allot of research and thought that the engine would have a roller cam ('97 merc brochure says all '97 V6s and V8s have roller cams) and flat top pistons w/9.1:1 compression ratio.

Well, I tore down the engine to make sure, before ordering parts for my winter project. After removing the intake, found no roller cam! Remove the heads and found what looks to be low compression type pistons. They are different than the old dish smog pistons.

I think low-compression pistons means vortec heads will be in my future d

Also, the exhaust elbows, risers, and manifolds look very good on the first quick inspection. Expected to run into a few stuborn bolts, but it went very well with no extra coaxing required.

 

[FreeBeeTony]

Re: Glad I waited until the teardown

I have the same pistons in my 350 Mag w/ a roller cam.
I installed the Vortec heads last fall..............very satisfied so far.

I'm surprised you already don't have the Vortecs with a '97.

 

[bruceb58]

Re: Glad I waited until the teardown

I believe the Vortecs started in the Mercs in 98.

Volvo appears to have done the same.

I wonder if Vortec heads were in short supply when they switched over to them in the trucks in 96.

 

[John_S]

Re: Glad I waited until the teardown

From that same brochure, merc offered numerous non-vortec head engines in '97. 5,7L, 5.7LX, and 350 mag were offered without vortec heads. There were three LX and mag models that were labeled gen+ that had vortex heads and either TBI or MPI. There was not a 2brl vortec head option. I believe in '98 the went to all vortec heads. I also think there was a few gen+ vortec models offered in '96.

 

[FreeBeeTony]

Re: Glad I waited until the teardown

What was the reason for the tear-down to begin with?

 

[John_S]

Re: Glad I waited until the teardown

To be sure of what was in there before deciding on what mods to go with. I considered using a bore scope to look at pistons, but couldn't find one locally to borrow or rent, that was cheaper than a set of head gaskets.

Instead of just a 4brl/intake, will probably go with vortec heads, and 4brl/intake. So far, it looks like converting to roller cam and associated parts, is not worth it. But will continue to hunt.

 

[Don S]

Re: Glad I waited until the teardown

In 97 Merc used the Vortec heads (and matching intake manifolds) on the EFI engines only, they were also know as the Gen+ engines.
Also, the piston cutouts are for the 5.7L engines (bigger valves), the 5.0L engine had flat top pistons.