Volvo 850, x70 oil cooler line block off testing in progress...

[rspi]

Hi guys, a year or so ago I was purchasing a seal for my daughter's oil thermostat from a trusted Volvo mechanic shop and the owner instructed me to block it off. I was shocked and immediately asked my mechanic in FL what he thought about it and he said that's one of the first things he does after getting a P80a vehicle (N engine). They claim that the oil cooler is more of an oil heater, not very effective as a cooler.

So, over the past year I have blocked off many of them with the NA plate. No issues that I know of yet. I have decided to test my daily driver in two ways:
1. Test the temp while driving.
2. Have an oil analysis done after 5,000 miles before and after the block off.

Today I will be installing an oil temp gauge with the sensor in the oil drain plug. I'm going to run this for 2500 miles with the oil cooler installed. Then I'm going to block off the oil cooler and run it another 5,000 miles checking the temperature highs, etc.

After each oil change I will be sending the oil to be sampled at Blackstone Labs. The lab results will tell if there is an issue with oil deterioration.

The newer RN oil pan has a better system that is believed to be more effective.

[Richard99]

Very interesting. I wonder if there is a better aftermarket cooler that could be installed...

[erikv11]

Very interesting. I wonder if there is a better aftermarket cooler that could be installed...

The newer oil pan (99+) with the biscuit oil cooler on the side of the pan is the easiest plug-and-play substitute. People have been doing that for years.

[abscate]

That reminds me to get rid of my crappy hose clamps on my biscuit oil cooler during CovidMaintenance

[rspi]

Very interesting. I wonder if there is a better aftermarket cooler that could be installed...

I'm sure it can be done, stand alone, like people do for the transmission.

[Richard99]

Very interesting. I wonder if there is a better aftermarket cooler that could be installed...

I'm sure it can be done, stand alone, like people do for the transmission.

Sounds like a good idea, as long as it doesn't restrict flow too much.

[rspi]

[JimBee]

Thanks, rspi for doing this analysis. I look forward to what your results!

[abscate]

Both my parts 1998 NA and my 1999 NA have no oil thermostat nor cooler of either kind.

Only my 1999 turbo has one

I think my 2005 NA has a biscuit oil cooler.

[bmdubya1198]

Not only is the oil to water oil cooler a better design, the lines aren't as much of a pain to install. And they don't leak as often! I'm interested to see the results of running without one. Due to the design of the -'98 oil cooler, I couldn't imagine that it does too much.