Help! I botched it! Oil overfill, coolant in oil after water pump r&r and oil cooler reseal.

Jon Schwenke

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1992 f250 7.3L idi - I'm hoping I didn't do any serious damage, and I just have a bad gasket or oring. Here's the deal.
I just replaced my leaky water pump and was sure to put RTV sealant on the center top and bottom bolts during install of the new one. I removed my oil cooler and replaced the inner oring seals and gaskets. I used a VERY light coating of rtv on both sides of the gaskets to assist in sealing possibly uneven and slightly pitted surfaces. After re-installation, I refilled with new coolant and I refilled the crankcase with what I thought were two 1 gallon jugs of oil +2 quarts. I must have been totally spacing out, because the jugs were 2 gallons, not 1. So, I filled my engine with 18 qts of oil and at that point did not realize it! I started the engine and ran it for maybe a minute and shut it down, checked the coolant level and added a touch more. I checked the oil level and saw it was WAY over the full mark. I started it again for maybe a minute, revved it a little thinking the oil needed to circulate since it had been completely drained over the course of a week, and then checked the level again. That's when I realized my mistake. I waited two days (due to rain) to drain the excess oil and today found straight coolant draining from my oil pan. When the oil finally started coming out it was grey like it had emulsified with the coolant. It appears that maybe 2 ish gallons of coolant was missing from the overflow and radiator, and it doesn't appear to have any oil in the radiator. A little over 5 gallons drained from the pan. I put the drain plug back in and am going to check it again maybe Sunday. So, here's the question(s). Do you think I damaged the engine???? HOPEFULLY it is the oil cooler orings getting damaged in the reassambly process or a bad gasket there. Possibly not enough sealant on the water pump bolt threads, but I'm not thinking so. I really could use some help determining the problem and where I should begin the diagnosis. Thanks in advance everyone. I feel awful about this.
 

Va_Mike

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I cant answer any of your real questions because those will only be known when you take things apart again. But I would start with draining the rest of the coolant and then flushing the block with diesel to help remove the coolant. after a first flush with just diesel I would do a 50/50 oil/diesel mix and crank it over (or start it for a min) to flush anywhere else the coolant could have gone. This is how we have always dealt with water in the oil situations with marine diesel engines.
 

Big Bart

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Move fast to keep the engine corrosion to a minimum. It is most likely your oil cooler seals. (Not likely 2 gallons of coolant leaked past the screws.). So pull the oil cooler and redo it. This time get all the RTV out from the o-ring surfaces, use new o-rings and o-ring lube or vasoline but not RTV. Make sure each end seats right and you seal up good to the block. (Hydraulic press works best, some have success with a ratchet strap.)

Replace the oil filter, add fresh oil, top off the radiator. Run and test.

Some other thoughts -
1) You did not say why you replace the pump and cooler seals. Did you have a issue? Keep in mind the possibility of your oil cooler is failing in one or more tubes, not at the o-rings. Perhaps the cooler failed from the removal, cleaning, and re-install. Not likely but possible, so don’t rule out.
2) Did you overheat the engine thus did the water pump? If so to your point, perhaps you blew a head gasket. And that is the leak, I would do the oil cooler first to rule out and make a good diagnosis.
3) Your local parts store will loan/rent you a radiator pressure tester to perhaps help find your leak if not the oil cooler o-rings.
4) Run for a few miles and change the oil and filter. Do it again at 100 miles. From what you see then you will know if it needs it in another 100 miles.
 
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Jon Schwenke

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Move fast to keep the engine corrosion to a minimum. It is most likely your oil cooler seals. (Not likely 2 gallons of coolant leaked past the screws.). So pull the oil cooler and redo it. This time get all the RTV out from the o-ring surfaces, use new or-rings and o-ring lube or vasoline but not RTV. Make sure each end seats right and you seal up good to the block. (Hydraulic press works best, some have success with a ratchet strap.)

Replace the oil filter, add fresh oil, top off the radiator. Run and test.

Some other thoughts -
1) You did not say why you replace the pump and cooler seals. Did you have a issue? Keep in mind the possibility of your oil cooler is failing in one or more tubes, not at the o-rings. Perhaps the cooler failed from the removal, cleaning, and re-install. Not likely but possible, so don’t rule out.
2) Did you overheat the engine thus did the water pump? If so to your point, perhaps you blew a head gasket. And that is the leak, I would do the oil cooler first to rule out and make a good diagnosis.
3) Your local parts store will loan/rent you a radiator pressure tester to perhaps help find your leak if not the oil cooler o-rings.
4) Run for a few miles and change the oil and filter. Do it again at 100 miles. From what you see then you will know if it needs it in another 100 miles.

I cant answer any of your real questions because those will only be known when you take things apart again. But I would start with draining the rest of the coolant and then flushing the block with diesel to help remove the coolant. after a first flush with just diesel I would do a 50/50 oil/diesel mix and crank it over (or start it for a min) to flush anywhere else the coolant could have gone. This is how we have always dealt with water in the oil situations with marine diesel engines.
Mike, Thank you for the advice. I'll get on that as soon as I'm able.
 

Jon Schwenke

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Move fast to keep the engine corrosion to a minimum. It is most likely your oil cooler seals. (Not likely 2 gallons of coolant leaked past the screws.). So pull the oil cooler and redo it. This time get all the RTV out from the o-ring surfaces, use new or-rings and o-ring lube or vasoline but not RTV. Make sure each end seats right and you seal up good to the block. (Hydraulic press works best, some have success with a ratchet strap.)

Replace the oil filter, add fresh oil, top off the radiator. Run and test.

Some other thoughts -
1) You did not say why you replace the pump and cooler seals. Did you have a issue? Keep in mind the possibility of your oil cooler is failing in one or more tubes, not at the o-rings. Perhaps the cooler failed from the removal, cleaning, and re-install. Not likely but possible, so don’t rule out.
2) Did you overheat the engine thus did the water pump? If so to your point, perhaps you blew a head gasket. And that is the leak, I would do the oil cooler first to rule out and make a good diagnosis.
3) Your local parts store will loan/rent you a radiator pressure tester to perhaps help find your leak if not the oil cooler o-rings.
4) Run for a few miles and change the oil and filter. Do it again at 100 miles. From what you see then you will know if it needs it in another 100 miles.
Hey Bart, thanks for the good suggestions. I replaced the water pump because it was leaking through the weep hole pretty bad. I had not overheated it to my knowledge. I did the oil cooler because it was leaking oil at the block and possibly from the orings. They were VERY brittle when I removed them. I did not put rtv on the new orings upon reassembly, just some grease to help with assembly. I used a 12 ton bottle jack on it's side and some 4x4 lumber on the floor in a block wall hallway to press the heads back on they did seat all the way, but could have *possibly* sustained damaged in the process. The RTV was on the gaskets. My hope (and best guess) is that maybe the RTV on the gaskets got boogered during the reinstall. I should also mention that there has never been any signs of water in the oil before I took everything apart and reassembled, so it more than likely was not preexisting. Thanks again for the suggestions, I'll get to applying them as soon as possible.
 

Big Bart

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John,

To clarify a little better. I meant to suggest there is a small chance by working on your oil cooler, it caused it to fail and now leak internal to it.(Not from the o-rings.) Not common but if yours was very corroded or you reemed out the tubes to clean them, there is a possibility the corrosion was plugging up the leak. So if on take 2 it leaks again let us know. There is a write up in how to make a tester.

Sounds like you are on the right track. Once you pull it you will likely be able to see if the block gaskets where the issue. The o-rings are the more frequent challenge.

Let us know hot it goes and attach some pic’s.
 

Jon Schwenke

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John,

To clarify a little better. I meant to suggest there is a small chance by working on your oil cooler, it caused it to fail and now leak internal to it.(Not from the o-rings.) Not common but if yours was very corroded or you reemed out the tubes to clean them, there is a possibility the corrosion was plugging up the leak. So if on take 2 it leaks again let us know. There is a write up in how to make a tester.

Many including myself could still see light pitting in the end caps after cleaning them. If severe and it leaks again you may need to replace them. But several have done this work and had issues with the o-rings when replacing them. Good new is most had success the second time. A few have used RTV, but most of us have used o-ring lube like Dow Molykote, Parker O-lube, or regular vasoline. All three will help it slide on and fill a minor pit or two.

My gut is the oil cooler seals did not seal properly, folded or got nicked/cut, that is why you lost so much coolant in the engine in such a short time. Since you used RTV on the water pump bolts, it is likely they are leaking. But don’t rule it out.
Hey Bart, yeah, there was some corrosion in the cooler heads and on the oring mating surfaces of the tube. I believe I cleaned them fairly well with some emory cloth, at least I felt it was ok. Again, there was no RTV used on the orings, just some grease. I did not ream the tube at all, it didn't appear to need it. First thing I'll do is check the pan again to see if it's still getting coolant in there. Then...drain everything and remove the cooler, assess the gaskets and see if I can detect a failure between the passages. Next, I'll try and find that write up on pressure testing the cooler. Question... should I leave the RTV off of the gaskets next time? I was concerned because of small pits on the block and cooler mating surfaces and put a film of RTV on both sides to prevent leaks. I read that some do and some don't do this. Thoughts?
 

Old Goat

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Here is a good write up repairing the Oil Cooler.


Goat
 

Big Bart

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Hey Bart, yeah, there was some corrosion in the cooler heads and on the oring mating surfaces of the tube. I believe I cleaned them fairly well with some emory cloth, at least I felt it was ok. Again, there was no RTV used on the orings, just some grease. I did not ream the tube at all, it didn't appear to need it. First thing I'll do is check the pan again to see if it's still getting coolant in there. Then...drain everything and remove the cooler, assess the gaskets and see if I can detect a failure between the passages. Next, I'll try and find that write up on pressure testing the cooler. Question... should I leave the RTV off of the gaskets next time? I was concerned because of small pits on the block and cooler mating surfaces and put a film of RTV on both sides to prevent leaks. I read that some do and some don't do this. Thoughts?
Jon,

I am not a big fan of RTV under pressure. 10-15 psi is fine but 40-60 psi I get concerned it will blow out. In my oil cooler gasket kit from Mahle the oil cooler to block gaskets where paper thin. Too thin For RTV in my opinion. So I used Permatex high tack gasket sealer to glue them to the block and coated the mating surfaces of the oil cooler to glue/seal them together. High tack is a thin gasket sealer, (But will fill pit marks.) more like rubber cement than RTV. I am no expert in RTV but I feel a thick coating/piece could blow out.(Or cause a gasket to snag and tear.) When I did my o-rings, I used Dow Mylikote lube on the o-rings as well. But grease should also work. Members have had success with Vasoline.

I think when you pull it off you will see if the oil cooler to block gaskets failed, if not pull the end caps to look at the o-rings. Also in my opinion emery cloth is perhaps a little too abrasive and would leave scratches the o-rings might not be able to seal against. Perhaps use some 220 grit sand paper or steel wool this time. But maybe the seals just got pinched or nicked and it had nothing to do with emery cloth.
 
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TNBrett

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I think it’s highly unlikely that the issue is either the water pump bolts or the oil cooler gaskets. I personally have never seen an issue come from “Painting” a thin layer of RTV on either side of a paper gasket. I have used High Tack in the past, but I prefer to use Ultra Black RTV 99% of the time. I feel like it sticks better, especially when oil or coolant is involved.

As far as the water pump bolts, for coolant to make it to the oil here, the water pump gasket would have to be leaking as well. Even if that were the case, 2 gallons is a lot of water to weep past the threads of those bolts.

I think it has to be either one of the inner o-rings(that separate the oil and coolant) or the oil cooler core itself. The fact that the oil is milky indicates that it has been run with the coolant in the oil. If you only ran it for a couple of minutes, I think the coolant started leaking into the oil as soon as you started filling the radiator. I think the overfilling with oil was just a coincidence and if anything, it helped you notice the issue much sooner hopefully preventing more serious damage. But, I don’t think you did yourself any favors by putting the drain plug back in the oil pan after draining it. I’m guessing the rest of the coolant has probably made it’s way there by now. In hind sight leaving the plug out, with a bucket under it would have been wiser.

I think you will find one of the inner o-rings cut, or pushed out of place. You did use all 4 o-rings didn’t you??
 

Jon Schwenke

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Ok guys, thanks for all your responses and suggestions.

Bart, my gaskets were paper as well and felt exactly the same way as you, that they would fail if not assisted. I chose a thin layer of Permatex Ultra Black.

TNBrett, yes, maybe so on the drain plug. I was thinking I wanted to see if it was still draining there or forced by pressure with the engine running. I'm not sure that logic holds, 'cause a bucket would have revealed the same...but that's why I did it.

I got the cooler out and it appears the RTV and gaskets held well, the gaskets kind of delaminated from themselves when I took it off the block. It is possible that they failed and that was part of the issue. I can't say for sure. The main issue however, was that one of the inner rings indeed got sliced during installation. So guys, whats the consensus here. Should the smaller Orings go on the tube or in the heads for install? I put them in the heads, and that may have been the issue. Thoughts? Pics below because someone asked for them!
 

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Jon Schwenke

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I think it’s highly unlikely that the issue is either the water pump bolts or the oil cooler gaskets. I personally have never seen an issue come from “Painting” a thin layer of RTV on either side of a paper gasket. I have used High Tack in the past, but I prefer to use Ultra Black RTV 99% of the time. I feel like it sticks better, especially when oil or coolant is involved.

As far as the water pump bolts, for coolant to make it to the oil here, the water pump gasket would have to be leaking as well. Even if that were the case, 2 gallons is a lot of water to weep past the threads of those bolts.

I think it has to be either one of the inner o-rings(that separate the oil and coolant) or the oil cooler core itself. The fact that the oil is milky indicates that it has been run with the coolant in the oil. If you only ran it for a couple of minutes, I think the coolant started leaking into the oil as soon as you started filling the radiator. I think the overfilling with oil was just a coincidence and if anything, it helped you notice the issue much sooner hopefully preventing more serious damage. But, I don’t think you did yourself any favors by putting the drain plug back in the oil pan after draining it. I’m guessing the rest of the coolant has probably made it’s way there by now. In hind sight leaving the plug out, with a bucket under it would have been wiser.

I think you will find one of the inner o-rings cut, or pushed out of place. You did use all 4 o-rings didn’t you??
LOL, yes I used all 4 orings. The next day I drained the pan again and it had a quart+ of coolant in it. Thanks for the thoughts and suggestions.
 

quickster

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IIRC the water pump bolts have specific holes to go into. I think 3(?) bolts go into the block. They need to be rtv'd. It's been a long time since I did a water pump, but I know a few bolts go through.
 

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