4.3 Rebuild

[Lou C]

Good luck with it and report back!!!

 

[gergAlicious]

Will do!! Everything is setup for blocking off (ports on thermo housing) and I got a shraeder valve with a 1/8” x 1/4” pipe adapter to go into other side of block. Heading back to house now to test.

 

[gergAlicious]

So here is my setup:

Only initial leak was here - raw water input. Tightened the plug and went away

Holding this for about 7 minutes now. Letting it set longer. I think I read 15 minutes? That is what my timer is set for.

 

[gergAlicious]

OK - first pass lost 1 pound in 15 minutes.

Got the soapy water bottle out and found the circulation pump hose connection and the port side, lower exhaust hose connection were both seeping air.

Cleaned both (after tightening didn't work) and re-pressurized.

No more leaks.

Going another 15 minutes now. :thumb:

 

[gergAlicious]

OK - she's been holding 15lbs for well over 1/2 hour.

I feel like things are looking good?

Going to ride it out through a full hour.

Ready to start bolting on accessories!! :madgrin:

 

[gergAlicious]

Fix it

All - would a push rod for the same engine setup (roller rockers / lifers) from a comparable GM 4.3 engine be OK for this engine or is there some magic ninja sauce in the actual Mercruiser push rods?

Had a small faux pas and a couple of mine got wet, and pitted some. Hoping to source locally and cheaper

Trusted brands I have used before are all < $5 per push rod. Mercruiser is ~$30 each :facepalm:

 

[gergAlicious]

90+ minutes and still looking good.

Looks like my new thread got merged with this one - didn't mean to break forum decorum . . . but topic name changed too.

Headed to parts store for push rods.

 

[Scott Danforth]

nothing special, mercuiser bought the motor from GM. hit your local napa

 

[Lou C]

Great, like your set up for pressurization!

 

[Bondo]

but topic name changed too.

Ayuh,.... Let's keep this build all in 1 thread, for the full story,.....

The mod tools can get wonkysometimes,....

pm me with whatever ya want for the title, 'n I'll change it,....

I lost the ole one, Somewhere,....

 

[gergAlicious]

Thanks guys!

Got three push rods from AutoClone and they are in.

So here is where I am - engine pressure dropped ~ 1/2 pound in 3 hours.

I had installed and torqued the rocker assemblies in the mean time.

I know each time I lifted the port side valve cover I had to flex the hose that is looping that side exhaust connections (hose overhanging the valve cover).

So $50k question - is 1/2 pound in 3 hours alarming?

Thanks again!!

 

[gergAlicious]

Considering cobbling together a run stand / base. Any measurements / info hiding here for that?

I see a lot of engine vids running on what looks like a ground level base / support.

Also need to figure out how / what to connect electrically - or would I plug into the 10-pin connector with individual bullets?

 

[GA_Boater]

90+ minutes and still looking good.

Looks like my new thread got merged with this one - didn't mean to break forum decorum . . . but topic name changed too.

Headed to parts store for push rods.

Ayuh,.... Let's keep this build all in 1 thread, for the full story,.....

The mod tools can get wonkysometimes,....

pm me with whatever ya want for the title, 'n I'll change it,....

I lost the ole one, Somewhere,....

All fixed with the posts in the correct order. I made up a name for the title, want it changed, let us know.

 

[gergAlicious]

Many thanks!!!!!

 

[gergAlicious]

Should be dressed out by tomorrow.

Now to figure out a ground level stand to run it on, and where to tap into the 10-pin connector for essential power to do so.

 

[Rick Stephens]

I would think you wouldn't lose any air pressuring a sealed water jacket.... so I don't know what 1/2 pound in 3 hours would indicate.

So what needs power: starter and ground. Purple for ignition, fuel pump and choke. A wire to run up to slave solenoid - touch to start.

After being fully dressed I set my 4.3 on hunks of RR ties and stuck a few lag bolts in it. My garden hose screw end screwed in perfectly to the soon to be replaced transom hose going to the oil cooler.

 

[gergAlicious]

Trying something a little different. Filled with water and repressurised this morning.

 

[Lou C]

I wonder if you could use a radiator pressure tester somehow if you want to test it with water in the cooling passages? I think the issue would be getting it 100% full, you'd have to remove the thermostat and put a hose in the outlet of the stat housing facing straight up. Prob just easier to use air pressure. However, water is what is important in this case lol.

 

[gergAlicious]

Agreed! I figured it would be something to try - and the block is likely only half to mostly full. I did fill the top side of the thermostat too. I'm just going to run it on the ground as suggested here by many. Plan to get a small support / frame together today out of 4x4s and lag bolt it to the setup.

I read above here that I really needed power to the starter / ignition etc. But do I need the 'computer' that is bolted to the port side riser energized for anything to make it run? Figure on a test light to show oil pressure like I have on the VW run stand.

 

[poconojoe]

Following along...very interesting thread.