divil

I spilled coolant into my oil filter hosing. It might have been as much as 1/4 of a cup or so. I had the filter removed to make room to get the headers out, and I realized I had to disconnect the metal heater pipe too. So I clamped off the rubber hose and pulled out the pipe, but it still spilled coolant - I presume most or all of it went into the filter housing.

Now, the question is, can I just drain the oil, and assume that the coolant will all be in the oil pan? Or do I need to crank it over a few times to make it circulate back to the pan? The car has been sitting for a week at this point so wherever the coolant is going to drain to, it's there now. But I'm not familiar enough with the path the oil takes to know where it would have ended up.

Thanks!

Swenny

Don't start it. Drain the oil,take off the oil cooler and clean it up (good time to do the cooler seals)-the oil filter is part of that set up. I would even take compressed air into the oil pathways after the cooler is off. Good luck.

divil

Do you mean the oil pathways on the cooler, or the block?

What I was thinking was, pull the fuel pump fuse, crank the engine over a few times, and then let it sit for a long time. Surely that would result in everything ending up in the pan, except trace amounts of water that would quickly evaporate when running?

Swenny

If you look at the block you can see where the coolant spill has a chance to go. Compressed air may or may not help to evacuate the stuff from the oil passage ways. You can leave the drain plug off and inject oil into the heat exchanger oil passages to help it drain. You might do a search online to see if anyone has done this before (spilled coolant in the oil filter housing) and see what their fix was. You dont want to see the milkshake looking oil. Drain the oil first and see if it all comes out.

divil

Thanks. I've done a fair bit of searching, and either no one else is stupid enough to have done this before, or no one else is smart enough to be concerned about it lol! But I think I know which one it is...

I'll definitely drain the oil before I do anything else.

V2Rocket

the "oil filter nipple" is the return path to the engine AFTER getting filtered.

the circumferential passages are the feed from the oil pump TO the filter.

were it mine i'd just spin it on the starter for 10 seconds or so to blow it through the system, let sit to drain down, and then change the oil the next day.

engine not running, no real load on bearings or anything, you're talking about ~2 oz of coolant (which is somewhat slippery itself) in a 200+ oz system.

divil

Looking at it again, it seems very unlikely that much of the coolant would have made it into the centre hole. I just drained the oil anyway, and I couldn't see any coolant, but I think it's probably lost in there as you say. I'm thinking I'll crank it over a few turns tonight, without starting it, and give it time to drain.

I'm debating whether to drain the oil again tomorrow after doing that.

mj951

Maybe pour a quart or two of oil down the filter housing (where coolant went down) to help flush the block, drain all that at once. If you're indoors leave the drain plug out overnight.

divil

Thanks for suggesting this - you may have saved me some trouble! I just removed the filter and tried pouring oil in, both into the centre hole and the surrounding holes. It wouldn't take more than a drop before it started spilling out. But while I was doing this, I noticed something - there's a little sort of trough between the oil filter housing and the block - just part of the casting I suppose - but it was full of coolant! Somehow, that's where most of my coolant went, it seems.

I've been thinking about how this could have happened. This area where the coolant was is definitely not directly under the hose. What I'm thinking now is, the coolant spilled onto the open area of the filter housing, but with that being already full of oil, the coolant just ran off onto the ground and into that little trough.

I cranked it a few times until I saw the oil pressure needle move, and now I'll let it sit overnight. I got some more oil in case I decide to drain it again tomorrow, but I'm pretty sure not as much went in there as I thought.

mj951

I'm not very familiar with the oil flow and passages in the block but for sure you'll have to pour the oil very slowly for it to drain back into the motor. Would also remove the fill cap and dip stick.
I know the trough area you're describing that caught some of the coolant. Would be very lucky to get coolant in the trough and at least not some coolant in the filter housing and down into the motor. That said, I think draining, filling, cranking, draining again and finally filling again, you'll be fine.

Dan Martinic

I followed Tom's guide for HG replacement--which is a great guide--and there's a step to remove the oil filter. A few steps later, coolant drains directly into the oil filter housing: the only part of the guide I feel needs "updating" lol

Anyway, I was also doing the oil thermostat housing seals. I drained the oil and did notice lots of coolant came out. When finished, I filled the engine with the cheapest oil I could find; it was a 10w30 called "Peak" and it flowed like water. Literally. With DME relay unplugged, I cranked the motor a few times until I saw oil pressure. Then I drained that water-oil. Next, I filled it up with better oil but still not my usual type. This time, I ran the engine till fully warmed up. Drained again. Finally, I filled it up with the usual stuff and it's been good since.

The whole "oil-in-the-filter-housing" cost me a couple of cheap oil changes, but I figure better safe than sorry. I still don't get how that "Peak" oil can possibly have any viscosity!?

divil

Well thanks for all the input everyone. I ended up not changing the oil a second time. It just seemed like overkill. I've been driving the car a fair bit since then so if there was any coolant left it's gone by now.