Newbie rebuilding 4.3l mercruiser

[hudsonc2004]

How's it going everyone. First time posting! This is my first boat! I've been working on cars since I was young though so I'm very knowledgeable when it comes to wrenching.

I bought a 1988 Regal Medallion 185 a couple months ago with a blown motor. Paid 1000 for it. The previous owner removed one of the heads and left a bunch of water sitting for awhile causing plenty of pitting corrosion in the cylinders. They told me it lost compression in two cylinders and upon inspecting the head gasket I found that it was torn so that was the issue. Long story short i just finished rebuilding the engine! Only reason it took so long was machine shop took their sweet time!

I just started it up for the first time today and am super excited! Had a great time rebuilding this engine. This is number two for engines I've rebuilt myself. First one being a subaru. Anyways! Just wanted to share with y'all! Any tips for me for when I actually take it out to the lake? Again this is my first boat and have never launched one let alone driven one! Thanks!!

I should have taken alot more pictures but hands were usually covered in grease most of the time!

 

[alldodge]

Welcome aboard
Did a nice job and thanks for sharing. Hope next time you start a project maybe let us in on it as you go so we can make side track ya whith some "what if" things

 

[achris]

As this was your first marine engine I'll ask a few questions.
1. You removed the drive before removing the engine?
2. You used marine head gaskets and brass (or stainless steel) core plugs?
3. You checked and adjusted the engine alignment before refitting the drive?
4. You serviced the drive water pump before refitting the drive?

Nice job on the rebuild...

Chris.

 

[hudsonc2004]

As this was your first marine engine I'll ask a few questions.
1. You removed the drive before removing the engine?
2. You used marine head gaskets and brass (or stainless steel) core plugs?
3. You checked and adjusted the engine alignment before refitting the drive?
4. You serviced the drive water pump before refitting the drive?

Nice job on the rebuild...

Chris.

Thanks Chris!

1. I did remove the drive.

2. I did alot of research before I made my decision on this. Seems like everyone's opinion is different but I went with automotive head gaskets. Seems like alot of marine companies are selling snake oil also it'll only see fresh water.. I'm sure I'll get alot of flak for this but it's my engine! But appreciate any constructive criticism that'll come my way. Machine shop installed stainless steel plugs.

3. I did check Alignment with an alignment tool.

4. I cracked open the water pump to check for corrosion and it looked good inside so I sealed her back up and slapped it on. I planned on replacing it and have an extra in the garage but I'll keep it as a spare just in case.

Clayton

 

[hudsonc2004]

Welcome aboard
Did a nice job and thanks for sharing. Hope next time you start a project maybe let us in on it as you go so we can make side track ya whith some "what if" things

You're right I should have started it before! Next time will do that for sure.

 

[achris]

...2. I did alot of research before I made my decision on this. Seems like everyone's opinion is different but I went with automotive head gaskets. Seems like alot of marine companies are selling snake oil also it'll only see fresh water..

While I agree with you about a lot of 'marine' is just a 'tax', in the case of head gaskets, it's not. A lot of automotive head gaskets have steel in them. That's not good in a marine environment (salt or fresh!). You CAN get away with automotive head gaskets, as long as they are 'all composite' gaskets...

Even in fresh water, steel gaskets will rot.

Chris.........

 

[hudsonc2004]

While I agree with you about a lot of 'marine' is just a 'tax', in the case of head gaskets, it's not. A lot of automotive head gaskets have steel in them. That's not good in a marine environment (salt or fresh!). You CAN get away with automotive head gaskets, as long as they are 'all composite' gaskets...

Even in fresh water, steel gaskets will rot.

Chris.........

I can appreciate that. Is this from experience?

I actually did use a composite head gasket. I figured if the gasket fails then that'll be my que to upgrade to a v8 .

 

[achris]

I can appreciate that. Is this from experience?

Yes. I use to be own a service shop. Was a Mariner outboard/Mercruiser dealer, back in the 90's. I don't push the 'dealer' line, and recommend people buy parts from the OEM where possible, not Merc! But there are some real differences between automotive and marine on a lot of things. Things electrical and fuel systems especially (starter motors, alternators, distributors, fuses, relays), but a few that people don't really 'see' until explained, like head gaskets. And yes, I've seen rotted out automotive head gaskets on boat engines.

I actually did use a composite head gasket. I figured if the gasket fails then that'll be my que to upgrade to a v8 .

Composite should be fine.

 

[Lou C]

Fel/Pro makes a nice set of marine head gaskets for those engines and intake gaskets as well, I used both when I did my top end overhaul 4 years ago. I'm in salt water so I have to use marine...
Nice job looks like the machine shop did a great job. The little 4.3 is a nice engine, they are durable and cheap to rebuild.

 

[hudsonc2004]

Yes. I use to be own a service shop. Was a Mariner outboard/Mercruiser dealer, back in the 90's. I don't push the 'dealer' line, and recommend people buy parts from the OEM where possible, not Merc! But there are some real differences between automotive and marine on a lot of things. Things electrical and fuel systems especially (starter motors, alternators, distributors, fuses, relays), but a few that people don't really 'see' until explained, like head gaskets. And yes, I've seen rotted out automotive head gaskets on boat engines.

Composite should be fine.

Hey that's awesome appreciate the information. I assume the differences are more corrosion resistant?

I guess that makes sense that there would be rotted put head gaskets. Well I hope my gaskets hold up! I mean the engine as a whole is made out of cast iron so have you seen them usually last awhile before corrosion takes over?

 

[hudsonc2004]

Fel/Pro makes a nice set of marine head gaskets for those engines and intake gaskets as well, I used both when I did my top end overhaul 4 years ago. I'm in salt water so I have to use marine...
Nice job looks like the machine shop did a great job. The little 4.3 is a nice engine, they are durable and cheap to rebuild.

I looked at the felpro set but I couldn't justify the cost. The machine shop did do a good job! But that's where alot of the funds went so I ended buying most of my parts from rock auto on the cheap! I'm pretty confident though in the build.