Oily sludge and its eventual destruction (a work in progress)

[jbg]

There was finally a break in the rain and I was able to drain and refill. The clumpy oil is less and less and the drain-off is mainly dirty water.

[v8volvo]

Good stuff. You must have the drain-fill-bleed process down to a science now. Have you changed the rad already or still running the old rad? A lot of the remaining oil now might be trapped in either the rad core, or the high points of the engine, esp the expansion tank. When you get to the final drain, replacing the rad and removing the exp tank and any upper hoses (eg cold start upper hose, upper rad hose, etc) for thorough cleaning with soap and hot water might be a good concluding step.

We'll have to keep collecting ideas for a coolant sticky -- we have talked making an FAQ section on here for a while, seems like this topic and questions about timing and timing belts are some of the most common discussions on here, so would be nice to organize some of the info that has been posted over time in one place.

[jbg]

Originally Posted by v8volvo

Good stuff. You must have the drain-fill-bleed process down to a science now. Have you changed the rad already or still running the old rad? A lot of the remaining oil now might be trapped in either the rad core, or the high points of the engine, esp the expansion tank. When you get to the final drain, replacing the rad and removing the exp tank and any upper hoses (eg cold start upper hose, upper rad hose, etc) for thorough cleaning with soap and hot water might be a good concluding step.

I have not yet changed out the radiator, I plan to do so when I finish cleaning out the system; I reckon 2-3 more iterations. I do have the process down pretty good now. It's broken into 4 main tasks: 1) getting the system to operating temperature, 2) voiding the system, 3) added soap and water, closing the system, and 4) checking for leaks and topping up. I'm also determined to keep things as clean as possible, and off the ground as much as possible! Not that my car itself is clean ... I just want the ground clean.

1) Getting the system to operating temperature

Once the engine is warm after a drive I shutdown the engine and place a wide bucket under the radiator barb.

2) Voiding the system

I have several socket extensions on a socket wrench to access the lower radiator hose clamp from the top of the engine. I make sure to clock the hose clamp pointing up so this is a repeatable convenience. Loosening that hose clamp slowly allows a small trickle to drain out; this is very controllable. I then remove the expansion tank cap at which point the liquid flows faster. I slowly back the lower hose off the barb and hold it pointing down to direct the liquid into the bucket. After 15 seconds or so I let the hose hang freely and allow it to drain for several minutes. Squeezing the lower radiator hose near the thermostat seems to help in getting the last drops out.

At this point I loosen the hose clamp for the injection pump's thermostat hose. I place the hose into a plastic container, and install a 10" section of 3/8" hose and clamp back on the injection pump thermostat housing. I then place this hose into the same plastic container making sure it's still the highest point to aide in avoiding air in the system.

At this time I put several paper towels into the expansion tank and swab out the oil that has now pooled together in sticky clumps. I also pour water into the tank to help flush residual oil out.

3) Added soap and water, closing the system

The lower hose is now re-installed and the hose clamp tightened. I add two cap-fulls of soap and add water. Water is added until the expansion tank fills about half way. I then wait about 10 seconds for the level to go down a bit. At this time the disconnected injection pump hose, that is still connected to the cylinder head, will start draining black-colored water into the plastic container. I then keep pouring water into the expansion tank until the water starts to run clear(er).

The 3/8" hose I connected to the injection pump thermostat housing will have several inches of water in the hose, some might have even poured out into the plaster container. This hose is removed and the original re-installed and its clamp tightened. Paper towers under this hose keep most of the black water from getting everywhere.

4) Checking for leaks and topping up

I top-up the water level in the expansion tank to the "high" mark. Then I check for leaks and take it for a drive the next day. After that drive I usually need to add about 2 cups of water to bring the expansion tank level up to about half way on the scale.

Originally Posted by v8volvo

We'll have to keep collecting ideas for a coolant sticky -- we have talked making an FAQ section on here for a while, seems like this topic and questions about timing and timing belts are some of the most common discussions on here, so would be nice to organize some of the info that has been posted over time in one place.

Good idea, I'll have my neighbor help me get some pictures of the process. Sometimes 4 hands are better than two!

[jbg]

With the weather forecast showing that we'll be getting our first freeze tonight I had to relent and replace the water/soap with anti-freeze/soap. The seventh drain was 90% clean water. There was oily sludge in the coolant overflow bottle like always, albeit less. I put in some Peak brand anti-freeze and I am hoping to get one last time to perform an eighth drain / replace before winter officially sets in.

I feel good about the progress I've made so far. I plan to run the same radiator and hoses over the winter. In spring I'll do another 1-2 drains and replace the radiator, hoses, and finally get the oil leak figured out -- the original point of this thread in the first place!

[Goteborg Vapenfabrik]

Hey, Jim, I've read this thread since I'm interested in removing the stock oil cooler, do you have any updates on the 740? Your process is very detailed, thanks for sharing.

[jbg]

Originally Posted by Goteborg Vapenfabrik

Hey, Jim, I've read this thread since I'm interested in removing the stock oil cooler, do you have any updates on the 740? Your process is very detailed, thanks for sharing.

Hello there,

I've been using the car semi-regularily for the last few years. I'm glad my posts were entertaining to you, they are to me too! As this car is mainly a hobby (and my job is a few miles away) I don't need it to be 100% reliable. However good reliability is great! I wrench on it from time to time when it needs things or I get excited about adding or changing something.

I'm slowly degreasing and testing a used wiring harness I bought from Anders a while back. My current harness is a copper rats nest that is way past its time. I'm also trying to figure out why my battery keeps going flat after ~5 days of not starting it. Looks like my multimeter will be getting some use this weekend!

[Goteborg Vapenfabrik]

Based on your experiences with the oil in the cooling system, removing the stock oil cooler isn't a difficult decision, glad I got it off before it failed. The engine wiring harness is not that hard, it's eight wires, on the 740 diesel I bought the sensor for the glow plug system had for an unknown reason been removed, and the wiring harness was a total mess, getting a good one installed is a relief. Certainly, owning a RWD diesel powered passenger vehicle in the states leaves one few options, these Volvo's are definitely worth saving.