Oil in the Antifreeze

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Stanp1

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Folks

I have a 1989 4.3l OMC. I have oil mixed with the antifreeze in the purge bottle. Also, there is a film of oil on the radiator cap on top of the heat exchanger.

I am running this motor at 3900 RPM cruising at 26 to 28 mph. I'm wondering if there is a leak at the head gasket pushing oil into the water jackets on the intake manifolds.

Any Idea what's going on? Should I tighten the heads with a torque wrench to spec?
 
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Stanp1

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Re: Oil in the Antifreeze

Sorry,

"I'm wondering if there is a leak at the head gasket pushing oil into the water jackets on the intake manifolds." This doesn't make sense. However, is this a bad head gasket? There is no anitfreeze mixing in the Oil pan.
 
Bondo

Bondo

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Re: Oil in the Antifreeze

Ayuh,... Donno where it's coming from, other than it's Impossible to be coming from the headgasket...
 
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Stanp1

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Re: Oil in the Antifreeze

Bond-o said:
Ayuh,... Donno where it's coming from, other than it's Impossible to be coming from the headgasket...
Click to expand...

Bondo,

I did re-use my old intake manifold when I had a new block installed. It's pretty rusted out. any chance antifreeze is mixing here? I did have an intake manifold bolt leaking oil, 4th one back on the SB side. I pluged the bolt with RTV to stop the oil leak.
 
Bondo

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Re: Oil in the Antifreeze

Stanp1 said:
Bondo,

I did re-use my old intake manifold when I had a new block installed. It's pretty rusted out. any chance antifreeze is mixing here? I did have an intake manifold bolt leaking oil, 4th one back on the SB side. I pluged the bolt with RTV to stop the oil leak.
Click to expand...

Ayuh,... That makes more sense...
 
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Stanp1

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Re: Oil in the Antifreeze

Bondo,

What would you recommend doing with the old manifold? torque the bolts to spec? or replace the whole thing with a new one?

I've been thinking of changing out the old 2 bbl setup for a 4 bbl. This is not a vortec 4.3l. Is there a match for a non-vortec 4 bbl manifold? Or should I stick with a replacement 2 bbl. the boat could use the added HP from a 4 bbl, but it may be more of a headache.
 
Bondo

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Re: Oil in the Antifreeze

Stanp1 said:
Bondo,

What would you recommend doing with the old manifold? torque the bolts to spec? or replace the whole thing with a new one?

I've been thinking of changing out the old 2 bbl setup for a 4 bbl. This is not a vortec 4.3l. Is there a match for a non-vortec 4 bbl manifold? Or should I stick with a replacement 2 bbl. the boat could use the added HP from a 4 bbl, but it may be more of a headache.
Click to expand...

Ayuh,... That's probably what I'd do,...
There's All kinds of choices out there, both stock iron, 'n aftermarket aluminum...
 
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HT32BSX115

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Re: Oil in the Antifreeze

Stanp1 said:
I did re-use my old intake manifold when I had a new block installed. It's pretty rusted out. any chance antifreeze is mixing here? I did have an intake manifold bolt leaking oil, 4th one back on the SB side. I pluged the bolt with RTV to stop the oil leak.
Click to expand...

Howdy,

I confuse easily! How did you have a rusted out manifold if the engine was closed cooled?


If you had an intake manifold bolt leaking oil, you must have had fairly high crankcase pressures building up. (and still do maybe)

Maybe you have a plugged "breather" that is not allowing crankcase pressures to vent (usually into the flame arrester)
 
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Stanp1

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Re: Oil in the Antifreeze

"How did you have a rusted out manifold if the engine was closed cooled?"

HT3...,

The original engine had a raw water cooling setup. I replaced the engine and added an aftermaket heat exchanger. The mechanic re-used the old intake manifold. The gromits, hoses and holders are all clean and where they should be on the flame arrestor.
 
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Stanp1

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Re: Oil in the Antifreeze

Guys,

I want to convert a non-vortec 4.3l OMC 2 bbl to a merc 4.3 LX from 1996. Here are the list of parts I am looking at, can you tell me if they will bolt up to my current block:

MERCURY MERCRUISER 9600S 1255 CARBURETOR
MERCRUISER 4.3L INTAKE MANIFOLD WITH THERMOSTAT HOUSING

There is a throttle cable bracket as well. I want to use my exisiting distributor setup if possible. Can I used the exsisting mechanical fuel pump and re-route the fuel line to fit?

Here is a link to the manifold:

http://cgi.ebay.com/ebaymotors/MERC...at_Parts_Accessories_Gear&hash=item3f09690923http://cgi.ebay.com/ebaymotors/MERCRUISER-4-3L-INTAKE-MANIFOLD-THERMOSTAT-HOUSING-/270740818211?pt=Boat_Parts_Accessories_Gear&hash=item3f09690923
 
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Stanp1

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Re: Oil in the Antifreeze

I grabbed this quote from Bondo from another site:

"Ayuh,.... The motors tagged Vortec built before 1996 are Not Vortec motors,... It's Just the name Vortec...
The Vortec heads,+ intake were Intro'ed in 1996....

True Vortec motors have only 8 bolts holding the intake to the heads,...
Pre-vortec uses 12 bolts..."

I think I'm good to go as far as the manifold fit. I'd still like to know if the mechanical fuel pump and OMC ditributor will work.

I love these sites, I get all the answers I need.
 
Bondo

Bondo

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Re: Oil in the Antifreeze

I think I'm good to go as far as the manifold fit. I'd still like to know if the mechanical fuel pump and OMC ditributor will work.
Click to expand...

Ayuh,... That's a pre-vortec manifold, 12 bolts...

The fuelpump, 'n distributer don't care...
 
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HT32BSX115

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Re: Oil in the Antifreeze

Stanp1 said:
"How did you have a rusted out manifold if the engine was closed cooled?"

HT3...,

The original engine had a raw water cooling setup. I replaced the engine and added an aftermaket heat exchanger. The mechanic re-used the old intake manifold. The gromits, hoses and holders are all clean and where they should be on the flame arrestor.
Click to expand...



Ok....Got it.

Now if you want to quote something...... Use the quotes that are provided above ......when you click View attachment 91611
It will place a set of quotes in your message. that look like the following.

'[QUOTE ]************[/QUOTE ] The "***" is the text that you can type inside the quotes. and it will appear like your quote above.

If you highlight (left-click & drag) the text you want to quote, then click that little icon, it'll place those "quotes" around the text you want to quote!

Be sure to check your breather to ensure that you don't have crankcase pressure building up.


regards,


Rick
 
Joshua Nichols

Joshua Nichols

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Re: Oil in the Antifreeze

The motors tagged Vortec built before 1996 are Not Vortec motors,... It's Just the name Vortec...
The Vortec heads,+ intake were Intro'ed in 1996....

True Vortec motors have only 8 bolts holding the intake to the heads,...
Pre-vortec uses 12 bolts...
Click to expand...

Good info right there.. Bondo your the man
 
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