Coolant in my engine oil

[121GWATT]

When changing my oil recently I noticed green coolant draining out with my engine oil. I'm not sure how long this has been happening. There is no coolant leaking from underneath the car, and there doesn't appear to be any coolant being burnt during the combustion process. I'm hoping this is only a head gasket problem.

What are other people's experiences with coolant in the oil? And what are the most likely causes?

And then the big question... is my engine pooched? Or is it salvageable?

Thanks in advance.

[Delorean Industries]

One of three things has happened.

Your cylinder liner lower seals are failing
Head gaskets failing
Engine block rotted out in valley and water pump leaking at same time.

[David T]

Coolant in the oil is a big deal. If you keep driving with it you will ruin the motor. You need to find and fix the problem. Was the motor ever overheated? If so you probably just need head gaskets.

[121GWATT]

Engine didn't seem to be overheating. And yes, thankfully as soon as I saw the coolant in the oil I immediately stopped driving the car.

Looks like I'll have to start taking apart the engine to find out exactly what's going on. Any decent online walkthroughs out there on engine dis-assembly?

[David T]

Engine didn't seem to be overheating. And yes, thankfully as soon as I saw the coolant in the oil I immediately stopped driving the car.

Looks like I'll have to start taking apart the engine to find out exactly what's going on. Any decent online walkthroughs out there on engine dis-assembly?


The Workshop Manual is your best reference. When removing the heads you must know what to look for to see evidence of head gasket failure. If you can't see that you may have to assume a liner seal failure and that would mean taking the liners out. Heads can be done with the motor in the car but to do the liners the motor should come out.

[Rich]

Looks like I'll have to start taking apart the engine to find out exactly what's going on. Any decent online walkthroughs out there on engine dis-assembly?

Based on the good advice so far in this thread you could still hope that somehow it's "only" a failed head gasket and rule that out first. Have a mechanic sniff the coolant tank for signs of combustion gases or buy a test kit for head gasket checking.
LINK: Combustion-Leak-Detector (http://www.amazon.com/Lisle-75500-Combustion-Leak-Detector/dp/B0007ZDRUI/ref=sr_1_2?ie=UTF8&qid=1434677303&sr=8-2&keywords=head+gasket+test+kit)
Your "not overheating" note suggests this isn't the problem but it's easy to rule it out sooner than later.

If it's time to tear it down the next-easiest thing to check may be the in the VOD. Pull the intake manifold to see if there's evidence of leaking coolant in the valley - and, if so, any hole in the top of the block that the coolant found into the crankcase from there.

[David T]

Based on the good advice so far in this thread you could still hope that somehow it's "only" a failed head gasket and rule that out first. Have a mechanic sniff the coolant tank for signs of combustion gases or buy a test kit for head gasket checking.
LINK: Combustion-Leak-Detector (http://www.amazon.com/Lisle-75500-Combustion-Leak-Detector/dp/B0007ZDRUI/ref=sr_1_2?ie=UTF8&qid=1434677303&sr=8-2&keywords=head+gasket+test+kit)
Your "not overheating" note suggests this isn't the problem but it's easy to rule it out sooner than later.

If it's time to tear it down the next-easiest thing to check may be the in the VOD. Pull the intake manifold to see if there's evidence of leaking coolant in the valley - and, if so, any hole in the top of the block that the coolant found into the crankcase from there.

To pull the heads he has to remove the intake manifold so he will see if the top of the block has any problems at that point and if so he doesn't have to pull the heads. One thing that can be done, get the crankcase pan off, pressurize the cooling system and maybe you can see where the leak is. If it is a lower liner seal it should be easy to see.

[121GWATT]

Excellent advice, thank you to all so far. Looks like I could be going on quite the repair journey here. Oh the adventures!

[Jeffu]

get the crankcase pan off, pressurize the cooling system and maybe you can see where the leak is. If it is a lower liner seal it should be easy to see.

+1 agreed with Dave

If it is the liners, don't waste your time on the NOS paper replacement shims. Source out the metal Volvo replacements (part# 1218421) that they now make which supersedes the previous paper ones. Use a light coating of Hylomar Blue sealant on each side and you are set!

35125

[SS Spoiler]

What would be the cause of High oil pressure? I'm starting to read 100, 110 lbs.
I do have severe blowby and some low comp. figures [30, 65, 80, 95, 120 and 175. Also
have BAE turbo. Assume ring lands are shot, going to check oil condition and level after
it cools down.

[SS Spoiler]

Ok, oil level is good, changed oil filter still high oil pressure. Sending unit?

[David T]

Ok, oil level is good, changed oil filter still high oil pressure. Sending unit?

First you have to confirm the actual pressure and make sure it is not an instrumentation error. Remove the sender unit on the right side and hook in an accurate pressure gauge. If you do have high pressure that would mean the oil system is plugged up AND the bypass on the oil pump is not functioning. At this pressure you must be careful you don't blow the spin-on filter apart, they are not made for such a high pressure.

[SS Spoiler]

Ok, I didn't change the oil filter, I'm using one of those permanent oil
filters that a guy was selling at the Gettysburg show. Opened it up, cleaned it out
and reinstalled. Everything inside looked good, no buildup of anything. Replaced
oil sender with DMCMW upgrade in 2014. A mystery

[David T]

Ok, I didn't change the oil filter, I'm using one of those permanent oil
filters that a guy was selling at the Gettysburg show. Opened it up, cleaned it out
and reinstalled. Everything inside looked good, no buildup of anything. Replaced
oil sender with DMCMW upgrade in 2014. A mystery

Try an ordinary spin-on filter and get an accurate mechanical pressure gauge on the motor and see what the pressure is. I saw those "permanent" cleanable filters but didn't like them. A solution for a problem that doesn't exist. Spin-on filters are not THAT expensive and you don't change then that often.

[DMCMW Dave]

I'd still suspect the sending unit, new(ish) or not. It's pretty hard to have high oil pressure.

[PJ Grady Inc.]

What would be the cause of High oil pressure? I'm starting to read 100, 110 lbs.
I do have severe blowby and some low comp. figures [30, 65, 80, 95, 120 and 175. Also
have BAE turbo. Assume ring lands are shot, going to check oil condition and level after
it cools down.
It wouldn't be broken rings lands (although overboosting will certainly cause that via detonation) as that would cause a very noticable engine knock. Perhaps the rings have lost their tension/ seal with the liners. The big problem with the BAE turbo is oil use do to improper positioning of the seal retension groove IIRC. I think Bruce Benson and/or Marty Maier researched this heavily some years back. You must be using an external gauge to obtain that reading since the dash gauge only goes to 80 LB's. The sender is often the cause of the needle going above 80# if that's what's happening.
Rob

[SS Spoiler]

I was just guessing on the pressure reading off the dash gauge.
The blow-by is bad enough to pop the oil fill cap off. My milage has dropped
about a third and power is weak. It's crazy but it starts and runs well. Oil
is clean, smokes a little. Looks like an engine build this winter. Now the question
is keep the turbo and add forged pistons, or toss the turbo and go for cams and
headers. What's the best way to go? Meanwhile got a car show coming up.
Took another first place last week. Sometimes it's nice being the only DeLorean
in town.

Paul/Kate Cerny
# 2691 Kalispell, MT

[David T]

I was just guessing on the pressure reading off the dash gauge.
The blow-by is bad enough to pop the oil fill cap off. My milage has dropped
about a third and power is weak. It's crazy but it starts and runs well. Oil
is clean, smokes a little. Looks like an engine build this winter. Now the question
is keep the turbo and add forged pistons, or toss the turbo and go for cams and
headers. What's the best way to go? Meanwhile got a car show coming up.
Took another first place last week. Sometimes it's nice being the only DeLorean
in town.

Paul/Kate Cerny
# 2691 Kalispell, MT

From a purely economic standpoint you are probably better off keeping the turbo. From a performance and reliability prospective the Stage II is the way to go. If you keep running the motor you will be going for liners as well. If you pull the spark plugs you will be able to see which cylinders have the blown pistons. They will be the ones with oil all over the plugs.

[PJ Grady Inc.]

I was just guessing on the pressure reading off the dash gauge.
The blow-by is bad enough to pop the oil fill cap off. My milage has dropped
about a third and power is weak. It's crazy but it starts and runs well. Oil
is clean, smokes a little. Looks like an engine build this winter. Now the question
is keep the turbo and add forged pistons, or toss the turbo and go for cams and
headers. What's the best way to go? Meanwhile got a car show coming up.
Took another first place last week. Sometimes it's nice being the only DeLorean
in town.

Paul/Kate Cerny
# 2691 Kalispell, MT
Ok then changing the sender usually solves the gauge problem. Stay away from Fram filters as they tend to blow out the sender.

I have cams and headers should you decide to go that route. I also have NOS liners/pistons. If you keep the turbo get in touch with Bruce or Marty to get the details of their turbo fix for the BAE. If you do that then you could keep the turbo setup.
Rob

[Farrar]

OK, I'm a little late to the party, but here is some advice I found elsewhere, and perhaps it will be useful to the next person who has this kind of engine trouble.

If you get the cylinder at TDC compression stroke and put air in it, there are a couple of things you can do, assuming your valves are properly adjusted. If you have a compression tester, remove the Schrader valve in the bottom of the tube that screws into the spark plug socket. Now you can put shop air into the cylinder. Once you have air flowing into the cylinder, there are three tests that you can do.


1. take the radiator cap off and look for bubbles. Bubbles could indicate a blown head gasket or warped/cracked head.

2. listen for air escaping out the oil dipstick. Air escaping here could indicate leakage past the rings.

3. listen for air escaping out the tail pipe. Air escaping here could indicate a leaky exhaust valve.


Kind of old school diagnostics, but might give you an idea of what to look for. I'm sure there's probably more to it, but that's all I can remember right now.

Remember, I am not a mechanic.

[PJ Grady Inc.]

OK, I'm a little late to the party, but here is some advice I found elsewhere, and perhaps it will be useful to the next person who has this kind of engine trouble.

If you get the cylinder at TDC compression stroke and put air in it, there are a couple of things you can do, assuming your valves are properly adjusted. If you have a compression tester, remove the Schrader valve in the bottom of the tube that screws into the spark plug socket. Now you can put shop air into the cylinder. Once you have air flowing into the cylinder, there are three tests that you can do.


1. take the radiator cap off and look for bubbles. Bubbles could indicate a blown head gasket or warped/cracked head.

2. listen for air escaping out the oil dipstick. Air escaping here could indicate leakage past the rings.

3. listen for air escaping out the tail pipe. Air escaping here could indicate a leaky exhaust valve.


Kind of old school diagnostics, but might give you an idea of what to look for. I'm sure there's probably more to it, but that's all I can remember right now.

Remember, I am not a mechanic.

These procedures you describe are for the use of a "Leakdown tester" which is much better than a compression tester. We use it in the shop to measure the amount of air excaping from the cylinder. More than 15% leakdown indicates a problem. Occasionally the leakdown is bad enough (over 20%) that your three listed steps can help pinpoint the cause of the leakage. A new broken in PVR engine usually has about a 3 or 4% leakdown rate.
rob

[SS Spoiler]

Thanks for the ideas. I will dive into it this fall after I win a few more trophies....ha

[Farrar]

These procedures you describe are for the use of a "Leakdown tester" which is much better than a compression tester.

I don't have a leak-down tester, but I have perfect hearing (at least according to the U.S. Air Force). ;)

[David T]

I was just guessing on the pressure reading off the dash gauge.
The blow-by is bad enough to pop the oil fill cap off. My milage has dropped
about a third and power is weak. It's crazy but it starts and runs well. Oil
is clean, smokes a little. Looks like an engine build this winter. Now the question
is keep the turbo and add forged pistons, or toss the turbo and go for cams and
headers. What's the best way to go? Meanwhile got a car show coming up.
Took another first place last week. Sometimes it's nice being the only DeLorean
in town.

Paul/Kate Cerny
# 2691 Kalispell, MT

If you have a turbo and you keep popping the oil filler off and blowing out oil, you overboosted and damaged pistons. Yes, you can do all kinds of testing but why? You already know you have damaged pistons and have to take the motor all apart. It is either that or get another motor.

[121GWATT]

Ok, so lets get this thread back on the original topic.
I pressurized the coolant system, but was unable to find any exterior leaks. But I removed the intake manifold I most definitely found out where all my coolant has been going (see photo)! F***! Not sure how long this has been happening. I cleaned up most of the coolant pooling. Still haven't found the source of the leak. Further investigation will have to wait for a couple days due to my schedule.

36100

[Riley88]

I don't have a leak-down tester, but I have perfect hearing (at least according to the U.S. Air Force). ;) I died laughing. Navy here, couldn't it be more true? YOUR HEARING IS FINE DAMMIT!

[DMCMW Dave]

Ok, so lets get this thread back on the original topic.
I pressurized the coolant system, but was unable to find any exterior leaks. But I removed the intake manifold I most definitely found out where all my coolant has been going (see photo)! F***! Not sure how long this has been happening. I cleaned up most of the coolant pooling. Still haven't found the source of the leak. Further investigation will have to wait for a couple days due to my schedule.


Drain the oil, and then pressurize the cooling system again with the drain plug out. That will show any internal leaks, i.e. cylinder jugs or certain forms of head gasket failure.

The valley leak is probably the hoses. There are quite a few connections that will dump into that area.

[DMC5180]

Judging from the green residue at each end of Y-pipe connection, it would be a strong indicator of leakage.

[David T]

Once you find leakage under the intake manifold it really doesn't matter what is leaking, you are going to redo ALL of the hoses, gaskets, and seals under there.

[DMC-81]

Once you find leakage under the intake manifold it really doesn't matter what is leaking, you are going to redo ALL of the hoses, gaskets, and seals under there.

+1.

It's also a great opportunity to clean the carbon out of your intake ports and manifold. I used cotton shop rags, and spray cans of carburetor cleaner. A one-foot piece of small wooden dowel helps reach the inaccessible areas with the rag. When cleaning the ports, to avoid having the cleaner wash down the cylinders, I sprayed the cleaner on the rag, not into the ports, (unless of course you can turn the crank to close the valves).

[PJ Grady Inc.]

Judging from the green residue at each end of Y-pipe connection, it would be a strong indicator of leakage.

Yes the block pipe hoses appear to be leaking heavily. I always change these out to silicone with the proper clamps so you won't need to go back and retighten them after they bed in. Someone has already switched out the hoses once and didn't use silicone apparently (the clamps appear to be the nonslotted style for silicone use strangly enough) judging by their dull appearance or you probably wouldn't have this mess. You should clean and decarbonize the motor and consider changing the dist. cap, rotor, wireset and plugs. A new slave cylinder may also save you grief in the near future as all that stuff looks pretty hammered. Don't forget to consider a new water pump too. It's so much easier to do all these jobs with the mnfd off theat you should strongly consider it. Change all of the fasteners too as they will be corroded. After that you'll have no need to visit the VOD for a very long time provided the block is still solid. A thorough cleanup and pressure test of the cooling system should be done before refitting the manifold.
Rob

[David T]

Yes the block pipe hoses appear to be leaking heavily. I always change these out to silicone with the proper clamps so you won't need to go back and retighten them after they bed in. Someone has already switched out the hoses once and didn't use silicone apparently (the clamps appear to be the nonslotted style for silicone use strangly enough) judging by their dull appearance or you probably wouldn't have this mess. You should clean and decarbonize the motor and consider changing the dist. cap, rotor, wireset and plugs. A new slave cylinder may also save you grief in the near future as all that stuff looks pretty hammered. Don't forget to consider a new water pump too. It's so much easier to do all these jobs with the mnfd off theat you should strongly consider it. Change all of the fasteners too as they will be corroded. After that you'll have no need to visit the VOD for a very long time provided the block is still solid. A thorough cleanup and pressure test of the cooling system should be done before refitting the manifold.
Rob

All of the vendors sell a master water pump kit but what they include can vary. The "while you are in there" can add up. In addition to all that is mentioned in the above post you can also add the idler bearings, the belts, the right upper muffler bracket, the S/S clutch hose, heater valve, all of the hoses (including the little vacuum ones), a S/S header bottle and more if I keep typing. Maybe exhaust manifold gaskets too. If you do your own work you can spend more on parts and get more done. This can grow to become one of the most costly areas but from a reliability standpoint it is one of the most important.

[Josh]

Took a look at the car in question. The coolant in the valley is indeed from the rotted out coolant hoses. The hater pipe is also pretty rusted; there may be a pinhole or two in it.
The coolant in the oil is still a major concern though. The block is solid, so no block rot mixing the leaky coolant with the oil via the upper oil galley. Im thinking a leak down test would be prudent...

[DMCMW Dave]

. Im thinking a leak down test would be prudent...

That finds bad valves or rings. Maybe a head gasket. I still think a cooling system pressure test with the oil drain open would be prudent.

[Farrar]

Oops - wrong thread. :)

[Josh]

That finds bad valves or rings. Maybe a head gasket. I still think a cooling system pressure test with the oil drain open would be prudent.

that would do the trick! Good advice as usual dave.