1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with oil

saltybutwet

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1993 Mercruser Alpha One 3.0 Litre Digital Electronic Ignition

Numbers From The Breather Cover
Engine Seral Number 0F023390 the 6th digit could be 3
0F023890 the 6th digit could be 8

Outdrive is a Mercruiser Alpha 1


Sorry that this is a little long, however I wanted to give as much info as possible, thanks for reading


I started a thread in another forum, however I feel like this thread will be in the correct location for some answers, and troubleshooting, with patience, I have, time I have, money limited

I bought this boat yesterday for $ 1300.00 knowing that it could possibly have a busted block, from improper winterizing from the po.

The po has already been messing with the engine trying to fix it, however they gave up, now it's up to me to move forward with the troubleshooting, some engine parts were already removed and laying in the engine compartment

Major Problems that I know of, as of today after some troubleshooting, here are my findings thus far

1. Water mixed with engine oil, oil level appears to be normal on the dip

2. Water oil mix, appears on the rockers , and push rods

3. No rust on rockers or push rods as of today

4. The intake was removed by the po, I inspected it, and it appears to have some type of repair on the casting, rust inside

5. The exhaust riser was removed by the po, it looks rusty inside

6. removed all the spark plugs, they look to be original? and the gap looked good, the center electrode has little wear, creamic around the copper core looked normal tan, and the ground electrode looked normal, timing on the grounding electrode looked in normal range, didn't appear to have been running hot

7. The hex of the spark plug , and the creamic insulator has some rust

8. I attempted to turn over the engine wth plugs removed, to ensure that it was not locked up. I do not have a locked engine , but at this point it just means the pistons aren't seized

This is as far as I got with the engine today

Now for the Alpha one outdrive testing

I used the power trim just to test it, and it works, however it pushes out milky fluid out the cap vent hole when operating
I am not sure what is the issue with this. I feel like water intrusion also.

Question
What is my next steps in troubleshooting?.

I do have a lot on knowledge of auto engines, small engines, ect, however the marine engine troubleshooting is a bit different
I have compression gauge, leak down testing equipment, about 20,000 dollars in tools and equipment in my shop, that i have accumulated over the years, so i am willing to test, teat, and test

thanks for any help that all can provide. I appreciate...hope this will not be a junk block...

pics below may help some
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0202141010_zps9ff2e08d.jpg


0202140958a_zpsa69c28c2.jpg


0202140958_zps0b1fb5e5.jpg


0201141525_zps61ec2dc7.jpg


IMG957779_zpsb51b7c45.jpg
 
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Bondo

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Ayuh,.... The best way to test the block's coolin' jacket it to, drain it, isolate it, pressurize with air, 'n listen,...

Is there water under the oil in the oil pan,..?? water is heavier, 'n will settle to the bottom,...
Ditto for yer drive,...

The trim system will need to be drained, purged, 'n refilled with fresh oil,...
Then ya gotta find out where the water came from,....
Possibly the pump was flooded, 'n it got in that way, donno...
Could be the seals on the rams,...
 

wrench 3

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

I don't like the look of the second picture. Looks like some one JB welded the block. You can water pressure test the engine by plugging the hose that ran from the thermostat housing to the manifolds and connect a garden hose to the hose running from the rear of the engine to the thermostat housing. If the drain plug is out of the oil pan, water will exit there if there's an internal leak.
If you have some heavy gasket material, you can make up a solid gasket to go between the manifold and the exhaust riser. Connect a garden hose to the hose from the thermostat housing to the manifolds and you can pressure test the manifold.
 

fishrdan

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

1- Drain the engine of water, remove the fresh water supply hose going to the engine, cap all other water passages, then test from where the fresh water hose connects to the engine to see if the block will hold pressure. 15PSI should do, and I suspect that you'll find the pressure dropping from a crack somewhere. Pic #2 shows a big grey splotch on the block which looks like JBweld to me... If the block is loosing pressure, listen for where it's hissing.

2- Check the manifold for cracks by filling the water jacket with acetone, then looking for acetone leaking out. With the rust marks in the head's intake runners, I would be very suspect of a cracked manifold. (or water got in through the carb).

If the block and manifold pass the pressure tests, install the manifold, change the oil and filter to get the milky oil out, then get the engine running ASAP to get remnant water out of the engine. Check for milky oil, some is to be expected with the prior contamination, but it shouldn't be bad or get worse the longer then engine is run.

For the trim pump, drain the reservoir, pull the hoses off the manifold under the gimble housing and manually lift/lower the drive to get the milky oil out of the trim rams. Reconnect everything, refill and run the trim up/down while checking the trim fluid level. Repeat drain/fill procedure until the trim fluid comes out perfectly clean. (My trim pump had water contamination which left a sticky/waxy layer of gunk over everything, had to tear the pump apart to clean it out.) Once the boat is in the water, check for milky trim fluid after the first couple of trips.

I would also drain the drive to see if it has water contamination.... And change the water pump impeller.
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Gosh! thanks folks! for the information
Now I have some sort of a starting pont

does this engine have an oil drain plug? I haven't checked yet. I do know that it has a threaded connector at the dip, for sucking out the oil, however I don't have a pump of that type yet.

I do agree with ya about what looks like jb weld on the block. I was going to kinda grind it off, and see what is under it

I will look for the block testing procedure, with pics, if there is any
 

Bondo

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Gosh! thanks folks! for the information
Now I have some sort of a starting pont

does this engine have an oil drain plug? I haven't checked yet. I do know that it has a threaded connector at the dip, for sucking out the oil, however I don't have a pump of that type yet.

I do agree with ya about what looks like jb weld on the block. I was going to kinda grind it off, and see what is under it

I will look for the block testing procedure, with pics, if there is any

Ayuh,... There's a Hole under it,... Grind it off, 'n ya gotta fix it Again,...

Pressure test it, if it don't leak, it don't matter,...
 

wrench 3

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

With that style dip stick tube they usually connect to the engine with a banjo fitting at the oil pan drain plug. Just watch out for gaskets when you pull the plug.
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

I don't like the look of the second picture. Looks like some one JB welded the block. You can water pressure test the engine by plugging the hose that ran from the thermostat housing to the manifolds and connect a garden hose to the hose running from the rear of the engine to the thermostat housing. If the drain plug is out of the oil pan, water will exit there if there's an internal leak.
If you have some heavy gasket material, you can make up a solid gasket to go between the manifold and the exhaust riser. Connect a garden hose to the hose from the thermostat housing to the manifolds and you can pressure test the manifold.

I don't like the look of that 2nd pic either, looks like the intake manifold gasket may have ruptured just above all the rust on the block.
The intake manifold is off, and was taken off by the po, the gasket is just laying in the engine compartment. I assume I will need to re-install this, along with the exhaust riser so can water test, though the intake gasket don't look to good.

I do have some heavy gasket material I can use for the exhaust riser

do I cut one end of the garden hose off? I am assuming I do
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Ayuh,... There's a Hole under it,... Grind it off, 'n ya gotta fix it Again,...

Pressure test it, if it don't leak, it don't matter,...

I got you, however I so some welding, and never used jb weld, is it any good?

Also if there is a hole under it, i assume it is in the water jacket area of the block?
 

Bondo

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

I don't like the look of that 2nd pic either, looks like the intake manifold gasket may have ruptured just above all the rust on the block.
The intake manifold is off, and was taken off by the po, the gasket is just laying in the engine compartment. I assume I will need to re-install this, along with the exhaust riser so can water test, though the intake gasket don't look to good.

I do have some heavy gasket material I can use for the exhaust riser

do I cut one end of the garden hose off? I am assuming I do

Ayuh,... Yer pressure testin' the Block, not the manifold,... Never reuse gaskets either,...

Isolate the Block's coolin' passages, then pressurize,...
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

With that style dip stick tube they usually connect to the engine with a banjo fitting at the oil pan drain plug. Just watch out for gaskets when you pull the plug.

any pics of what that looks like?
 

wrench 3

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Your engine doesn't have any water passages between the cylinder head and the manifolds, so they can be tested the way it is.
I have a replacement end for a larger garden hose that I clamp into the hose on the engine and then just screw on the garden hose.
 

wrench 3

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Ayuh,... Yer pressure testin' the Block, not the manifold,... Never reuse gaskets either,...

Isolate the Block's coolin' passages, then pressurize,...

Hay Bondo, what's wrong with pressure testing the block and the manifold? It's picked out a couple of bad ones for me in the past.
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Ayuh,... Yer pressure testin' the Block, not the manifold,... Never reuse gaskets either,...

Isolate the Block's coolin' passages, then pressurize,...

sorry, this is a new avenue for me, and I appreciate the advce
I was thinking I needed to re install all the removed parts, even the gasket that i would not have used, to pressure test. now you mentioned isolate the cooling passages? any ideas?
don't want to sound stupid lol
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Your engine doesn't have any water passages between the cylinder head and the manifolds, so they can be tested the way it is.
I have a replacement end for a larger garden hose that I clamp into the hose on the engine and then just screw on the garden hose.

think I know what your talking about, thanks
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

so, I will begin testing the block this week, after work when I have some daylight left. I don't have cover to put her under, so every thing will do, will be done outside, unless it rains, s too hot, snowing, sleeting, ect...here in Ga you never know what kinda weather your going to get lol

Now I have search, and read that almost all the 3.0 Mercruisers when they freeze ( if that is what happened to this one) bust the block, however the freeze plugs on this block are not busted. In my experience over the years, the freeze plugs on an auto will almost always blow, before the block cracks, kinda a safety feature

Now is that the case with these marine engines using raw water, shouldn't the freeze plugs blow before the block cracks?
 

wrench 3

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Now I have search, and read that almost all the 3.0 Mercruisers when they freeze ( if that is what happened to this one) bust the block, however the freeze plugs on this block are not busted. In my experience over the years, the freeze plugs on an auto will almost always blow, before the block cracks, kinda a safety feature

Now is that the case with these marine engines using raw water, shouldn't the freeze plugs blow before the block cracks?

To start off with, the frost plugs are not a safety feature. They are a core plug to fill the holes necessary for casting the block. But they do tend to push out if things freeze. Hence the name.
A lot of freezing damage in marine engines is from poor draining rather than none. Water gets left in from the drain plugging up before all the water gets out. So the ice may have been below the frost plugs.
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

To start off with, the frost plugs are not a safety feature. They are a core plug to fill the holes necessary for casting the block. But they do tend to push out if things freeze. Hence the name.
A lot of freezing damage in marine engines is from poor draining rather than none. Water gets left in from the drain plugging up before all the water gets out. So the ice may have been below the frost plugs.

I agree, just trying to figure this out
 

bonzoscott

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Just a side note to consider: I once flipped a bout with a 3.0 Mercruiser. It was the type that had an engine cover and side by side jump seats adjacent to the cover. The back of the cover, on top where it hinged was directly over the carb / flame arrestor (water straight down the carb). It had rust in the intake like yours does. After I got it running, it also had an intake leak and was way under torqued. Your motor probably has more going on with the JB weld, but I thought it was worth mentioning.
 

saltybutwet

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Re: 1993 Mercruiser 3.0 new to me, with major problems, Not Running, Water mixed with

Just a side note to consider: I once flipped a bout with a 3.0 Mercruiser. It was the type that had an engine cover and side by side jump seats adjacent to the cover. The back of the cover, on top where it hinged was directly over the carb / flame arrestor (water straight down the carb). It had rust in the intake like yours does. After I got it running, it also had an intake leak and was way under torqued. Your motor probably has more going on with the JB weld, but I thought it was worth mentioning.
you know I have thought about this boat possible being under water, possibly the engine bay.This boat is way to clean for a 93 year and the boat has not been on a trailer much, no trailer rash or nothing. I think it must have been a lake boat at a dock in water all the time, or something like that, maybe someone left the plug in and with no top, it has rained here so much over the last 6 months or so, maybe she filled with water
I hope the engine can be saved
how did you flip your boat?

looks like a lot of rust there to me
0202141010_zps9ff2e08d.jpg
 
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