Re-sealed oil cooler: afterthoughts and questions

[TexasAggie09]

After watching my oil leak get progressively worse, this weekend I finally decided to tackle it. To start, I replace the drivers side valve cover gasket. I had oil covering the whole drivers side of my engine all the way to the valve cover (some on top of the lip) and dripping from every point possible under my truck. I don't have to worry about my truck rusting! Cleaning it was impossible so I quit. While I had the valve cover off, I removed the CCV and added my own o-rings and RTV gasket maker to eliminate that as a possible leak point.

Next I drained the coolant (my procedure below, for anyone interested) and flushed it with the hose until everything ran clear. I also drained the oil. After that I removed the oil cooler and even though I dried everything, still got a nice oil and coolant shower. It was somewhat chilly today too. I used my dead blow to remove the end caps of the oil cooler and scraped the old o-rings out. The two smaller ones were essentially plastic and broke off in pieces. I cleaned up all the surfaces, lubricated the new rings and chamfers and put them in. Once I tried to to remount the oil cooler and found it was too long, I realized I left one of the old o-rings inside when I put it back together. Oops! Once I got it back together for real (with a ratchet strap and dead blow), I snaked the new gaskets in place and after many swear words, got the bolts in (thank you air ratchet!).

Once the oil cooler was replaced I refilled the oil and then flushed my coolant several times with plain distilled. On the last flush I put the thermostat back in and let it get up to temperature before draining it the last time. I filled up with some 50/50 EC-1 coolant and took her out on a spin. The temps are the same and I'm keeping an eye on the reservoir level. While I was out my squealing belt got way worse so I threw in a new belt and the squeal stopped. New oil cooler seals, new valve cover gasket, revealed CCV, new coolant, new oil, new belt. Not bad for a Saturday huh?

Some thoughts for anyone wanting to do it in the future:

NOTHING but the oil cooler bolts (and of course oil filter and block heater) needs to be removed or moved to take out the oil cooler on an OBS, in spite of what you may read. You can tetris it out.

Be prepared for a nasty driveway and clothes. I will be pressure washing my driveway tomorrow and my clothes are on a double wash with degreaser now.

Belt dressing sucks.

Make sure all old seals are out of the oil cooler prior to assembly.

Parts may fall out of the oil cooler during removal and fall into your bucket of old oil. You may not find out about these parts until you drain that bucket. You may also spend 1-2 hours on google trying to see how those parts (pressure valve) go back in. I hope I got it right!


And some questions:

I only refilled 5 gallons of coolant. What gives? I thought these things held 8? My temps are fine (temp gauge reads half way like it always did) and reservoir is full.


Coolant drain/flush procedure:

I did all my coolant draining by removing the smaller hose from the lower radiator hose. Its the hose connected to a T in the lower radiator hose and leads right up to the bottom of the reservoir. First I removed the bottom part of that hose and drained the radiator. Then I ran a garden hose into the reservoir and flushed it out clear. Then I removed completely the upper radiator hose and stuck the garden hose into the top of the radiator until it flushed clear. Then I removed the thermostat housing and the thermostat. I put the garden hose into the water pump and flushed it clear. I then wiggled the lower reservoir hose back one the lower radiator T. I replaced the thermostat housing (leaving thermostat out) and started the truck. I ran the garden hose into the thermostat housing and let the truck run for a while. Then I shut the truck off and disconnected the hose from the T again. I continued this procedure until everything ran clear. After removing and replacing the oil cooler, I flushed multiple times from the reservoir (with upper radiator hose replaced but thermostat still out) with distilled water. When I got down to my last flush, I replaced the thermostat and flushed once more, letting the engine get up to temperature. I drained it and replaced all hoses and clamps and refilled the reservoir with 50/50 EC-1 coolant and distilled water.

[rolsmojave3]

Sounds good to me. You only refilled 5 because you more then likely had some left in the block.

[BrianH]

Careful using any sort of tap water in your cooling system. The minerals in that stuff makes hell out of the cooling passages in the radiator and block.

[TexasAggie09]

Originally Posted by rolsmojave3

Sounds good to me. You only refilled 5 because you more then likely had some left in the block.

I got to thinking about it afterwards and you're probably right. I had thoroughly drained and flushed the old stuff and the several flushes of DI water but on that last flush, I only drained from the bottom of the radiator. My ratio is more likely 3 gallons of coolant and 5 gallons of DI water but as long as my temps are alright I'm not worried. I'll add more concentrate if it ever gets low.

Originally Posted by BrianH

Careful using any sort of tap water in your cooling system. The minerals in that stuff makes hell out of the cooling passages in the radiator and block.

The initial flush was with tap water (our city water is actually very soft) but I flushed with 16 gallons of DI water after all that and ran the engine multiple times to get it all out. Thanks for the advice!