55 series 62 coolant in oil

[mark55]

I have a issue with antifreeze getting into my crankcase on a 1955 series 62 with a rebuilt 331 v8. Note: Engine was rebuilt (25) years ago & reinstalled in the vehicle.
(I did not do the rebuild) I can see that when the spark plugs are removed the tops of the pistons are new. The radiator,heater cores are freshly rebuilt and my factory carburetor rebuilt.
I was expecting to finally be able to road test this vehicle & make some final adjustments etc.
When the engine is started cold & running on its fast idle approx 975 RPM
My engine oil pressure is reading 30psi (using a wet gauge tool)
The engine is running remarkably smooth & quiet with "NO" white exhaust
or any other color smoke for that matter.
The radiator coolant level has dropped so the top tank is empty though coolant can still be seen & I've probably drained as much of the lost coolant from my now "Brown murky" crankcase oil.
I'm sure if I drain the crankcase & leave the plug out of the pan I will just get antifreeze coolant. I could even put a pressure test tool on the radiator to speed the process up.
I'm thinking possibly whoever rebuilt this engine didn't have the block Magna Fluxed to check for possible water jacket cracks etc.
I guess my question is: Did the 331 v8 have issues or have I totally missed something??
Well thanks for listening & any helpful information would be appreciated

[wheikkila]

Lets not jump into a bad block yet. Lets start with something simple. I would pull the intake first just to make sure there is not a problem there.  If I didn't find anything, than I would boll both heads. It may not be that easy to spot. If this is a rebuilt engine started for the first time. I understand it is an older rebuild. I would not run the engine any more till it has been repaired. 
                          Thanks Wayne 

[V63]

The 331 intake does not have water in it.
Best not to run it with contaminated oil.
It certainly sounds as if it is not getting into the combustion chambers? (No miss no water in exhaust?).

I rebuilt a 365 once and learned its block was cracked (to the outside) and how I learned it was because I could see a 3" line of micro droplets of anti freeze along the crack. Anti freeze will Find a leak before water will.
Does your system pressurize? You might try and isolate the block coolant passages remove all the spark plugs , pressurize it with compressed air to see if you can hear a leak and isolate it?

Problem now is water/moisture is inside the engine and it will RUST.
Remove water from cooling system.
Remove crank case oil as best you can.

Minimally:
Remove the valve covers, oil filler  To allow moisture to escape.
Rinse valve train with brake clean, pour trans fluid into the cylinders leave Spark plugs out.
Remove intake and valley cover
Clean valley of contaminated oil.
Remove oil filter and drain it's housing.
Fill crankcase with fresh thin oil, new filter.
Crank engine, spark plugs removed to build oil pressure and flush clean oil thru it.

All said, Probably best to pull the heads, and all the tin (oil pan, valley, and front cover)

[mark55]

I did see the coolant flow pictured in the repair manual.
Your correct. The intake manifold has no water flow in it.

[mark55]

The 331 intake does not have water in it.
Best not to run it with contaminated oil.
It certainly sounds as if it is not getting into the combustion chambers.
I rebuilt a 365 once and learned its block was cracked (to the outside) and how I learned it was because I could see a 3" line of micro droplets of anti freeze along the crack. Anti freeze will Find a leak before water will.
Does your system pressurize? You might try and isolate the block coolant passages remove all the spark plugs , pressurize it with compressed air to see if you can hear a leak and isolate it?

Not sure about isolating the block coolant passages ??
I do have a air operated cooling system pressure tester I can use on the radiator to pressurize the system with the spark plugs removed

[PHIL WHYTE CLC 14192]

I had the same problem with my 54. It was a cracked head. It seems this was quite a common occurrence on the 331s. I managed to get a good replacement. I had both the new head and the good one (which had been welded by a previous owner) magnafluxed and pressure tested before I put them back on. This was on a rebuilt engine and the water had damaged a cylinder. I had the cylinder sleeved so I didn't have to buy a replacement set of oversize pistons as the ones in there were new. Good luck. Phil

[Tom Boehm]

Is it possible this could be as simple as a bad seal on the head gasket?

[fishnjim]

This is why I recommend to have any rebuild run on the engine stand or dyno before you put it in the car.
Best not to run it at all until the leak is fixed.  Quiet don't mean much yet.    It must be going through an oil galley or wall.   
I think you're just wasting time, if you go looking for the leak externally, as it's internal and you won't see it.  Dismantling will answer all the questions each one of the "tests" will ask.   You may not want to hear the results but that's life.   Grinch type Xmas present 4 U.
Take top off down to the block, and inspect.   You can spray the cylinders with WD40 to mitigate rusting and clean out the pan and oil pump, if you pull the pan.    Spray the crank area too.  May have to do dye penetrant or magnaflux for hairline cracks, if not obvious.   Your call if better to do on or off the car.   These fat fenders are difficult to work on for me.   You might get lucky and only a bad gasket, still has to be located but can't tell till it's apart.  I don't think you want to Xray your engine.   

I'm always suspect when things sit for a long period.   They sit for a reason. 
There's a history of head cracks with these early exhaust cross over motors.   I've got a 365 in parts partly sitting here that was under rebuild and sat for 10 years as the owner didn't pay.   It's got two cracked heads and they were refurbished(?).   It had a bad cylinder crack too and several sleeves already.   I bought it thinking I'd use it while the original was rebuilt, but it was a scrapper.   I was smart to have my rebuilder dismantle/go through it, first before I swopped engines.   He found all sorts of issues that went undetected.   We did salvage a bunch of new parts off it so was not a total loss.   I gambled a little money for time and lost.   C'est La Vie.

[Caddy Wizard]

I have had many 49-56 models.  And done much engine work on them.  The 55 heads are prone to cracking.  A bad head gasket is quite possible, as is a cracked head.  A cracked engine block is less common.


I would remove the heads and take them to a high quality automotive machine shop to be magnafluxed.  If check out okay, reinstall with new head gaskets.  If not, find new head(s)...

[mark55]

I have a issue with antifreeze getting into my crankcase on a 1955 series 62 with a rebuilt 331 v8. Note: Engine was rebuilt (25) years ago & reinstalled in the vehicle.
(I did not do the rebuild) I can see that when the spark plugs are removed the tops of the pistons are new. The radiator,heater cores are freshly rebuilt and my factory carburetor rebuilt.
I was expecting to finally be able to road test this vehicle & make some final adjustments etc.
When the engine is started cold & running on its fast idle approx 975 RPM is
My engine oil pressure is reading 30psi (using a wet gauge tool)



The engine is running remarkably smooth & quiet with "NO" white exhaust
or any other color smoke for that matter.
The radiator coolant level has dropped so the top tank is empty though coolant can still be seen & I've probably drained as much of the lost coolant from my now "Brown murky" crankcase oil.
I'm sure if I drain the crankcase & leave the plug out of the pan I will just get antifreeze coolant. I could even put a pressure test tool on the radiator to speed the process up.
I'm thinking possibly whoever rebuilt this engine didn't have the block Magna Fluxed to check for possible water jacket cracks etc.
I guess my question is: Did the 331 v8 have issues or have I totally missed something??
Well thanks for listening & any helpful information would be appreciated

[mark55]

I have removed approximately 1/2 gallon of coolant from my crankcase via the oil dipstick tube using a 3/16in. Brake line & air suction gun. I have also refilled my radiator with approximately 1/2 gallon of fresh coolant & have just let everything sit a few days(not starting engine) I've rechecked my levels today My coolant level in the radiator is still full & oil level is good. So naturally my I know my problem only exists when the engine is running. Even though as I have previous mentioned I don't have any misfire or white exhaust smoke etc.  I plan on removing all my spark plugs & charging the cylinders individually with air at 100psi. If I don't see any air getting into my radiator coolant/that should confirm I have no combustion leakage.
Next I will remove the rocker covers & pressurize the cooling system at the top of the radiator. Hopefully this may reveal a "Head bolt" that's allowing coolant leakage.
My 1954 Cadillac Shop repair manual mentions a engine block flushing procedure in the
"Cooling System" that has you removing certain #No. bottom head bolts for the flush but says nothing regarding using "Thread Sealer" on them when reinstalling them.
The cylinder head replacement section only lists a torque of 65-70 Foot pounds & doesn't mention anything regarding "Thread Sealer"
I'm assuming from what I've read in the "Cooling System Section" the bolts they have you remove go down into a water jacket area.

My question is: Does anybody know possibly from their past experience which bolts would require "Thread Sealer"  ? 

[Jay Friedman]

I have had many 49-56 models.  And done much engine work on them.  The 55 heads are prone to cracking.  A bad head gasket is quite possible, as is a cracked head.  A cracked engine block is less common.  I would remove the heads and take them to a high quality automotive machine shop to be magnafluxed.  If check out okay, reinstall with new head gaskets.  If not, find new head(s)...

In addition to what Art Gardner wrote, I would also check the length of the 12 bolts holding the exhaust manifolds to the cylinder heads, since if too long they can penetrate into water jackets.  The threads of these bolts are 3/8"-16 tpi.  However, their lengths are not nominal lengths.  Seven of them are 1 5/8" long and five are 2 3/8" long, which are uncommon lengths. 

Some years ago, after having my '49's 331 rebuilt I decided to replace these bolts.  Not being able to find the correct length bolts, I (foolishly!) installed 1 3/4" and 2 1/2" long bolts which are widely available.  Despite being only 1/8" longer than the correct bolts, the replacement bolts penetrated water jackets with dire results.  When I warmed up the motor, steam came out from around the bolt heads.  I didn't run the motor long enough to determine whether coolant entered an oil gallery or not. 

I had to remove the heads and take them to a machine shop which repaired them.  I eventually obtained new bolts of the correct length from the Fastenal Company.  My point is that even though you've not seen white exhaust or "any other color smoke" as I did, it's possible that the rebuilder may have used incorrect exhaust manifold bolts resulting in a cracked head. 

[mark55]

Thanks to everybody who replied to my previous posting regarding coolant in engine oil. Just a little update on a recent test I've just completed.
I filled my radiator coolant level all the way up to the bottom of "Filler Neck"
Removed all ( spark plugs & charged each cylinder (piston on top dead center)
with 100psi of air pressure each time looking for any air getting into the cooling system. I've even put a cooling system pressure test gage on the radiator neck & always have "0" pressure in the cooling system & no coolant loss.
With these test results I'm confident I don't have a "Head gasket combustion issue"

My next test will be to "Pressurize the cooling system" with the valve covers removed to see if I can locate any coolant leaking at the top of the heads.
(Possibly a Head bolt loose or in need of thread sealer)
Unfortunately in order to get the valve covers off. The "Cooling System" needs to be drained & (1) bottom head bolt on each head must be removed to get the "Power steering pump" & "A/C compressor" brackets out of the way. Then the (2) head bolts reinstalled & the cooling system refilled.
I believe this 331cid engine has (17) head bolts per side. What I've been researching & still don't know is: Do any of these head bolts especially the ones underneath valve cover require "Thread Sealer" to prevent coolant leaking into engine
Again thanks for reading

[J. Gomez]

Thanks to everybody who replied to my previous posting regarding coolant in engine oil. Just a little update on a recent test I've just completed.
I filled my radiator coolant level all the way up to the bottom of "Filler Neck"
Removed all ( spark plugs & charged each cylinder (piston on top dead center)
with 100psi of air pressure each time looking for any air getting into the cooling system. I've even put a cooling system pressure test gage on the radiator neck & always have "0" pressure in the cooling system & no coolant loss.
With these test results I'm confident I don't have a "Head gasket combustion issue"

My next test will be to "Pressurize the cooling system" with the valve covers removed to see if I can locate any coolant leaking at the top of the heads.
(Possibly a Head bolt loose or in need of thread sealer)
Unfortunately in order to get the valve covers off. The "Cooling System" needs to be drained & (1) bottom head bolt on each head must be removed to get the "Power steering pump" & "A/C compressor" brackets out of the way. Then the (2) head bolts reinstalled & the cooling system refilled.
I believe this 331cid engine has (17) head bolts per side. What I've been researching & still don't know is: Do any of these head bolts especially the ones underneath valve cover require "Thread Sealer" to prevent coolant leaking into engine
Again thanks for reading

Mark,

If you have the 1954-9155 Service Manual handy it will list the head bolts that do go into the water jackets (I believe you will need to get the 1954 Service Manual to get the details).

The ones inside the cover none of the bolts would need to be seal as they do not cross over the water jacket but the ones on the outside close to the exhaust manifold do, those would be second, third, sixth and seventh on both side (this is from the '56 Service manual). The cooling section list these for removal to flush the cooling system.

Although you have done a pressure check from the cylinder sides if you have a bad head gasket, a crack, and/or any other issues around these areas on the heads it is possible to get oil in the coolant.

Good luck..!   

[mark55]

J. Gomez   Thanks for the quick response !
I do have the 1954 Cadillac Shop Manual & the 1955 Cadillac Shop Manual Supplement. I did mention earlier in my posting that the shop manual (1954) has you removing certain #numbered bottom head bolts for "Cooling System" Flush Procedure & I would assume those bolts require thread sealer  But it doesn't say anything about "Thread Sealer". Not even in the "Engine Mechanical Section"
(Installation of cylinder head)
You answered my question regarding the head bolts underneath the valve covers.
Thank you.
Do you know if the #1 bottom head bolt that has the power steering bracket underneath it also goes into a water jacket area ??
Because if it doesn't I should be able to remove it along with the power steering pump/oil filter housing without loosing any coolant & be able to get valve cover off.
I know on the other (Right side cylinder head) the #3 head bolt has the A/C compressor bracket underneath it. So I would have to drain the cooling system to get that valve cover off.
Thanks again

[J. Gomez]

Mark,

Do you know if the #1 bottom head bolt that has the power steering bracket underneath it also goes into a water jacket area ??

I do not think this one goes through a water jacket as the next one does according to the Service Manual.

I do have the 1954 Cadillac Shop Manual & the 1955 Cadillac Shop Manual Supplement. I did mention earlier in my posting that the shop manual (1954) has you removing certain #numbered bottom head bolts for "Cooling System" Flush Procedure & I would assume those bolts require thread sealer  But it doesn't say anything about "Thread Sealer". Not even in the "Engine Mechanical Section"
(Installation of cylinder head)

You are correct the Service Manual for the Cadillac has a few caveats that are "head scratching" dealing with particular, maybe it was not a normal practice or they did not had the proper sealer back them to apply for these applications.

I know on the other (Right side cylinder head) the #3 head bolt has the A/C compressor bracket underneath it. So I would have to drain the cooling system to get that valve cover off.

The '55 rear A/C brackets is the same as the '56 so removing the valve cover does requires to removed them and the compressor unfortunately. There could be enough space to lift and move the compressor over to one side once the brackets are out but it will be a tight area aka knuckles busting as well. If you unit has the $$ R12 Freon I would just skip removing the compressor unless you must.

Good luck..!