Top-end rebuild. What else?
 

330/454 Mercruiser

I'm about to replace my manifolds & risers. Then, I figgered I should replace the head gaskets while my hands are greasy. Oops, gotta take off the intake manifold....change those gaskets too.

My question is, while I have the top-end apart, what else should I check, look for and/or replace?

Thanks in advance,

D. Ocean
Pompano Beach, FLA

Depends on how many hours are on the engine. I have seen 330's run for 500 hours without needing anything. If the motor is old, you may want to have the heads checked out. Older heads tend to rot out. New springs and a valve job may be something to look into, but those 330's seem to last forever. i wouldn't have even changed the headgaskets.

Were the manifolds and risers bad? Sometimes you get water into the engine if the riser goes bad, or manifold cracks etc.

>Were the manifolds and risers bad? Sometimes you >get water into the engine if the riser goes bad, or >manifold cracks etc.

Exactly. I just purchased the boat and am unsure of its maintenance history. Looking at some of the visible repairs, I have to assume the engine has been neglected or not maintained regularly.

So, while elbow-deep in Mercruiser guts, I thought I would do everything "right".

D. Ocean
Pompano Beach, FLA

Danny it also depends on how much you can do your self or how much you can get good help for cheap.
It would not hurt at all to have the heads gone over ie: big valves and pocket port job or even ditch the p-nut ports (if that is what you have) for some big ovals. I also think pulling the low pro cast iorn manifold off and replacing it with a better one would not hurt. Might as well toss some 1.8 ratio roller rockers on it also.

:D Rag's :D

Sheesh...and so it begins. I'm not interested in going faster, I just want to go!

I plan on dropping the heads off at a shop and having them checked/rebuilt professionally (if needed).

Thanks again,

D. Ocean
Pompano Beach, FLA

I Know of a set of used big block (gill Exhaust & tail pipes)
if you are in the market, I live in Pompano also.
You can probably get a good buy on them

L.S.

***

Danny,
Call me after 10 am
954 270-5999
Steve

While the intake is off, give it the hammer test under the t-stat crossover. I've seen too many people put bad intakes on rebuilds, only to let go prematurely and require another rebuild:mad: You don't have to hit too hard, but tap another area of the manifold and notice the ringing sound, tap area described and maybe notice a dull thud maybe with a little more hammer bounce. If this happens hit a little harder with ball pein end. maybe it will go through. If any doubt, throw it out. These parts are all over e-bay usually for $20 -$30 Because someone put an aluminum on on their car.