I'm a noob, I admit it. but I did things mostly by the book.

  • I had the heads reworked
  • I scraped the top of the engine block clean
  • I installed the head gasket dry as per the instructions.

  • I didn't follow a bolt pattern for the intake manifold but I tightened them through the course of a few iterations.

  • I used dabs of ultra black to hold the manifold gasket in place, as per the instructions.

  • I followed this bolt pattern for for my 99 Ranger V6 3.0L. I did use anti-sieze compound on the head bolts by mistake but I torqued it to the specs.

Well, at first it wouldn't start so I looked at the oil and it was already mixed with coolant. I figure maybe some of that was left over that didn't get drained out of the engine. So I bled off some oil and sure enough the watery stuff leaked out first and then it turned more oily.

Well, I finally got it running. I don't know what did it. I went to the parts store to get some fuel stabilizer and I put that in and it started immediately. Almost too immediately. I don't know if it started because I let it sit or because of the stabilizer. I think it was because I let it sit.

So I let it idle for 10 minutes and it's doing that fine. So I drive it around the block. After I accelerate a little the engine stalls. This happens a few more times. The temperature gauge was reading normal temperatures but I touch various parts of the engine and it's hot, which would explain the stalling and why the head gaskets got warped in the first place.

I replaced the water pump and thermostat. I was a little concerned about the thermostat because everyone says to put its spring facing the engine but it fit better with the spring facing up. I installed with the spring down (towards the ground/engine) though.

Anyhow, I check the oil after all this and it's light brown with a bubble or two. It looks like either my repair didn't fix anything or there was a lot of contaminated oil that never drained out of the engine.

So, I think I did things right but don't understand why it's still getting so hot and if/why coolant is still mixing with the oil.

  • 2
    Did you use new head bolts? Did you torque then correctly, using a degree wheel to set the final turns? How do you know the intake manifold isn't warped? There's a reason why there's torque sequence and why it should be followed. Commented Aug 3, 2016 at 1:24
  • Also, are you certain the coolant has been bled properly? Regardless of color, there shouldn't be any bubbles. Improperly bled coolant may lead to another overheating episode. And double verify, by whatever means, that the thermostat has been installed in the correct direction.
    – SteveRacer
    Commented Aug 3, 2016 at 6:23
  • I used new head bolts and torqued to spec and painted a line on the bolts to know how many degrees they turned. All I did to bleed out the coolant was turn the petcock on the bottom of the radiator. I've tried the thermostat in both directions now. This video youtube.com/watch?v=jqE4xlvdi38, in which the guy for some reason removes the entire radiator and fan installs the thermostat upside down compared to how everyone else says you should do it. But I've tried both directions now and I can't tell a difference. Commented Aug 3, 2016 at 15:16

4 Answers 4


Please consider this answer as "food for thought" and not as a reliable expert advice.

The most difficult part is to differentiate if the oil contamination is from the residual coolant in the not-totally changed oil or if there is still a leak present. You also need to exclude a present overheating problem.

  1. Check if there is an overheating problem and eventually correct it.
    • As Steve said: Check the thermostat installing direction.
    • Use a independent temperature sensor on the coolant hose / head to check if the temperature gauge is correct
    • Is the coolant flowing? If not: check for any obstructions or defect on the water pump. Did you used excessive sealing mass when installing the water pump?
    • Air trapped in the coolant circuit? Use all the available bleeding screws/taps of the coolant circuit to bleed the circuit / control for air pockets.
    • Does the radiator / heater becomes hot?
  2. Check if there is a problem with the head gasket and eventually correct it. If there is an oil cooler present: Check that first, eventually the head is alright and you can skip the head reinstall. Before you do it: Ask others for a second opinion about it. I personally would reinstall the head, especially if an overheating happened. In case you want to do it: Do as before, just pay attention to the following points:
    • Check if the engine block surface and head surface is straight. You need a precision knife-straight edge, made of hardened steel. enter image description here Check against a light source, if you see light shining between surface and ruler then the surface is not straight. Check the entire surface along the width and length, check also diagonally. Pay attention to not damage the surface.
    • Check for any grooves in the engine block / head. Those are normally very small. Pay special attention around the coolant/oil channels and between the cylinders. If in doubt: Put marking fluid on the surface and scrape it away with the precision ruler, the remaining spots would be the grooves. Check in two directions: Along the length and along the width. Pay attention to not damage the surface. Attention: The marking fluid test is overly sensitive, even unrelated grooves will appear.
    • Check the inside of the combustion chamber, especially in the head for any microscopic cracks.
    • If there are any grooves, cracks or warped surfaces: Consult with the guy who resurfaced the head. If you suspect that the resurfacing was not done right: Consult with another guy. It is possible the head has not enough clearance for a second skimming, then you will need either an real expert, a new engine-head or new car.
    • While the head is down: Inform yourself about bore glacing / piston damages and check for signs. I am sorry but these are out of my knowledge, I can't give you details I just know that these things exist.
    • When installing the head: New gasket required, ask the resurface guy about the needed thickness of the head-gasket. Clean out the anti-seize, use new bolts, lubricate them, respect the tightening instructions.
  3. Independent of any eventually head re-inspection:
    • Change the entire oil, including filter.
    • If the coolant is oil-contaminated: Flush it
    • Bleed the coolant
  • 1
    I do not understand why are you sure that the engine overheats? If the radiator gets hot it means that the coolant flows..
    – Martin
    Commented Aug 3, 2016 at 15:16
  • Cause even if I touch the upper intake it's HOT! The truck runs good when you first start it but gets worse and worse to the point where it will stall out. Like if you try driving it and get to a red light, if you've been driving it for 4-5 minutes it will stall and the engine will be super hot to the touch. No steam or smoke from the engine or the exhaust though. Just hot. Commented Aug 3, 2016 at 15:23
  • 1
    Is the fan running? Only chance to check for a oil-coolant leak would be to change the oil
    – Martin
    Commented Aug 3, 2016 at 15:35
  • yep, running. It runs right when you start the engine and there is a lot of wind from it. I actually took it out and reinstalled it to make sure it was pointed in the right direction. It sounds like the more pressing issue is just the overheating. Maybe the cooling system is working but the ratio of coolant to oil is creating extra friction? Commented Aug 3, 2016 at 15:47
  • Did you changed the entire oil? Hint: if you think that you need to change it soon again you can just use some cheap stuff. Are there bubbles in the coolant while running?
    – Martin
    Commented Aug 3, 2016 at 19:28

I'm just answering to record what it actually ended up being.

The water pump started grinding against its housing, the timing belt cover. Once the water pump cut all the way through coolant poured directly into the oil pan.

All it needed was a new water pump and timing belt cover.

  • 1
    Thanks for following up with what the problem actually turned out to be. Commented Dec 7, 2016 at 5:18

The problem most likely is when you failed to torque the intake manifold correctly (in sequence), you now have a warped intake which is dumping water down into the lifter valley, which goes directly into the oil pan from there. Your intake gaskets have lost integrity. A new set of gaskets and possibly a new intake manifold are going to be in order to solve this. It is probably why you are over heating, as well, due to the fact you have no integrity in the cooling system.


most likely the head was warped when it overheated and/or it is cracked, i hardly believe from the previous answer that it is a warped intake manifold thats some nonsense

  • 1
    Welcome to Motor Vehicle Maintenance & Repair! I'm not sure if you saw the answer posted by the OP, but it shows clearly what the issue was and how it was resolved. While my answer was not the cause, not sure why you'd consider it nonsense. I've experienced such an issue before, so know it can happen. As with a lot of answers on here, we can only state what we think the issue might be, based on the description in the question, personal experience, and possibly an educated guess. Just saying, don't discount it just because you've never experienced it. Commented Nov 11, 2017 at 5:41

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