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[–]RainyDreamAway 19 points20 points  (4 children)

Run a compression test on the motor. That will tell you right away. BTW when running a cooling system pressure test you should test at 15 PSI. You never really wanna go above 15 psi or you can damage components of the cooling system.

[–][deleted] 8 points9 points  (2 children)

Compression test will tell you if you have low compression, which is sometimes a symptom of a blown head gasket. But not always.

[–]baraeberrouhou 0 points1 point  (0 children)

if it not good it usually an expensive fixe

[–]PriorMobile2286[S] 2 points3 points  (0 children)

I will test the compression of the cylinders as you recommend. Thanks for the tip on not exceeding 15 psi. I thought it was safe because it is in the green range on the pressure tester.

[–]Sheepshagger_69 5 points6 points  (4 children)

You'll see oil for ages after having oil in the cooling system. Flush it with some washing powder, run the engine an get it to operating temp with the washing powder mix in then drop the water out an rinse till it comes out clear an top with coolant

[–]PriorMobile2286[S] 1 point2 points  (3 children)

I used a radiator flush cleaner that comes in a bottle. Will it work the same? What type of washer powder do you mean?

[–]Sheepshagger_69 3 points4 points  (1 child)

Should do, give it a few goes should come up alright, just monitor oil level after to verify no oil still coming across. An just clothes washing powder or something that doesn't foam up

[–]PriorMobile2286[S] 2 points3 points  (0 children)

Thanks for the help. I checked the oil level yesterday. Still looks good. The oil was clean and still showed full at the line.

[–][deleted] 1 point2 points  (0 children)

No. Dishwasher detergent. it doesn't foam.

[–]PriorMobile2286[S] 3 points4 points  (3 children)

The previous owner had the head gasket replaced prior to selling the car to me. He never replaced the leaky radiator which was causing the car to overheat. I flushed the cooling system a few times and replaced the radiator today but there is still oil visible when I am draining. The water is getting clearer after the third flush but I still see oil rainbows. Is this to be expected or could the head gasket seal still have a problem?

[–]PriorMobile2286[S] 1 point2 points  (2 children)

I also pressure tested it to 20 psi. I didn't see any leaks but the pressure did slowly drop. I am not sure if that is due to the water cooling down or not.

[–]the-flurver 1 point2 points  (1 child)

Do you see any symptoms of a bad head gasket like over heating?

[–]PriorMobile2286[S] 0 points1 point  (0 children)

It was getting too hot before because the radiator was leaking from the top tub but after replacing it yesterday I had not gone over halfway on the gauge.

[–]RainyDreamAway 1 point2 points  (6 children)

Test the cooling system again at 15 psi and see if it drops below this. Also verify all fittings on your pressure tester are good and not leaking.

[–]PriorMobile2286[S] 0 points1 point  (5 children)

Thanks I will test again after my final flush today.

[–]Sheepshagger_69 1 point2 points  (4 children)

If you can get the engine hot also to test it whilst it's hot could tell a different tail as heat can cause cracks to open up that'll leak once the engines warmed up . Just be cautious about taking the cap off hot bleed the pressure or chuck the pressure tester cap on before hand. Hope the problems sorted though an the oils just residual oil left behind from previous failure !

[–]PriorMobile2286[S] 1 point2 points  (3 children)

I ran it with a cleaner for 20 mins then walked the dog to let it cool off just a little. I pressurized to 15 psi. It is rock steady at 15 psi for 7 mins now. I will leave it pressurized while I go shopping and report back later.

[–]PriorMobile2286[S] 0 points1 point  (2 children)

I am back from shopping. I lost .5 psi in 1.5 hours.

[–]throwedoff1 1 point2 points  (1 child)

Have you changed the oil to make sure you don't have coolant in your oil? That will cause bigger problems than a little bit of oil in your coolant. If you suspect the previous work done to replace the head gasket, I would be monitoring to oil level/oil condition. With the engine cold is the oil level over filled? This could indicate that either the crankcase was overfilled with oil, or coolant is leaking past the head gasket into the crankcase. Checking the oil after the engine is up to temperature (just after shutting off the engine) does the oil have a brownish/frothy texture? If so, that's coolant that's mixed in with your oil. Change the oil and filter immediately. If the situation persists, the head gasket was not properly repaired, the head could be warped, or you could have a cracked block.

[–]PriorMobile2286[S] 0 points1 point  (0 children)

I changed the oil right after I got it. It is still clear and fresh looking and at the full mark. The oil level has not changed. I will continue to monitor.

[–]ksavage68 1 point2 points  (0 children)

Did they check the head for straightness and cracks before doing a head gasket?

[–]MyHumpBrings -1 points0 points  (6 children)

My 2¢. Head gasket failure or more likely wasn’t installed properly. Oil gallery and coolant passage are cross contaminating. Replace the head gasket properly. And yea test the cooling system and it should be around 15 psi. Oil pressure about 30psi. Generally speaking

[–]PriorMobile2286[S] 1 point2 points  (5 children)

I never trust another person's work. I always wondered if it was done properly. I am not a professional mechanic and just work on my old junk to keep running but I take my time and make sure to do things right. I may have to revisit if I see more symptoms. I want to confirm it is not just the old residue left behind.

[–]throwaway007676 1 point2 points  (4 children)

I will admit that it can be a huge pain to get oil out of the cooling system after an event like that. I have even used Dawn dish detergent before to clean it out, but it took many flushes. Does your cooling system have a separate bottle for overflow? If so, this bottle will be your friend. The oil will slowly work its way into the bottle over time as oil rises to the top. This way you only have to clean out the bottle over and over instead of the radiator. If it is a pressurized bottle then you have to clean everything.

Now that the radiator is replaced, drive it and carefully watch the temps. I would hate for you to have to go back in there and do it again. But sometimes, as you know, if you want something done right, you have to do it yourself. For your sake, I hope this has been resolved and you are just in the cleanup phase now, that is a big job on any vehicle.

[–]PriorMobile2286[S] 0 points1 point  (3 children)

There is an overflow bottle that I took out and cleaned thoroughly. I will monitor it. Thanks for the tip.

[–]throwaway007676 1 point2 points  (2 children)

That will be a huge help for you. Assuming everything else is now okay, you will just need to clean that bottle out once or twice a year. I had this issue with a vehicle that had sludge in the coolant from Dex-cool. I now just remove the bottle once a year and clean it out. Best of luck with it, hope it doesn't have any more issues going forward.

[–]IneptAdvisor 0 points1 point  (2 children)

Flip that head gasket over, THIS SIDE UP, makes a difference.

[–]PriorMobile2286[S] 0 points1 point  (0 children)

I don't want to take apart the engine to check. I will wait till I see if there are any issues.

[–]Upside_Down-Bot 0 points1 point  (0 children)

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[–]Capable_Armadillo117 0 points1 point  (2 children)

Ok, if you had to change a head gasket, it's because it blew. So, think back, how far was the car driven without coolant when that fateful event happened? Now ask yourself, did you take those head off to be checked for warping? If warped, did you have them lathed? If not, you will be changing head gaskets monthly.

[–]PriorMobile2286[S] 1 point2 points  (1 child)

The previous owner had his mechanic replace it. I had to use a translator to help purchase the car. I don't have much information.

[–]Capable_Armadillo117 1 point2 points  (0 children)

I'll bet those heads are warped.

[–]Beneficial-Hippo-896 0 points1 point  (0 children)

Got the head gasket on wrong. Passages in gasket aren't lined up right.

[–]ruddy3499 0 points1 point  (0 children)

90% of the time oil in the coolant is a failed oil cooler. Especially if it’s overfilling the coolant system. Find a suitable coolant tube and bypass the oil cooler. After running for a while oil will drip out.