Oil pressure/Oil cooler/Bearing health

S2_ITBVW

New member
We spun the #1 bearing testing a couple weeks ago. We just about have everything back together, but we are worried about what caused this in the first place. We have a pretty big aftermarket oil cooler on the car and the oil pressure is over 100 until the engine heats up (at which point it then drops into the 70-80 range). The oil pressure sensor is positioned just before the oil is pumped through the cooler. We were chatting about this and started to wonder if the oil cooler could be restricting the flow of oil in some way, maybe even enough to fail to lubricate things on the other end of the block.

Is this a legit concern? Does this even make any sense? :shrug:

TIA.
 
I don't know that much about the VW engine but my engine only has 60-70 lbs at start up and drops to 35-40 at idle when warm. When hot it drops a bit further but I don't remember how much. At speed I see 60-70 psi. I'm using 15W-40 oil. I do have an oil cooler with thermostat that directs some of the oil to the cooler but not all.

I take my pressure readings from a port on the oil filter bracket that bolts to the side of the block as the oil re-enters the engine. This is after the oil is filtered and cooled.
 
I thought that you got my book.. No oil cooler is needed for IT racing.The stock HOH to oil cooler is fine.
Just run 5/40 synthetic with a good pan. Dont bother with the oil temp guage. It gets hot for sure but will stay under 300 and not have any issues.
 
Oil Pressure / Bearing Health

I have been running VW's for years, and never had any bearing issues, unless there was an oil pump problem or starvation. Are you using a baffled pan, like the ones from Techtonics?, What kind of clearances are you running on the rods? and Mains?.... I have found out that the oil pumps do wear out and if the pan is not baffled, starvation is possible. I do run an external oil cooler, and have never had a issue on my Mk 1 and MkIII models, The Mk II always had high oil temps. But on my MK III, using Mobil 1, 5/30, at 220 deg, oil pressure still is abut 75 lbs at 6200. Higher on short courses with lower speeds. I would look for either at not enough bearing clearance, starvation, or pump failure.... My opinion....

David Ellis-Brown
 
Mike, we added the cooler for a bit of extra protection.

Dick, yes, we were using a FRAM filter. We will change that.

D. yes, we have a baffled oil pan. Clearance on the rod bearings is a consistent .002.

It may have just been a fluke, but we are trying to help it NOT happen again.

Thanks for the help!

DE
 
What size are your oil cooler lines?

You said the pressure gauge is right before the oil cooler. If the lines are too small, you will be chocking the flow, but the gauge will show the pressure is fine.
 
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The cheap STP filters look good also , nice big holes. The Mann has more holes but smaller.The fram is just plain junk.
FWIW most of the customer cars with blown up engines, have added coolers.
 
Properly installed an oil cooler will not create a problem, it is more likely that you had a low oil level, or no baffling like suggested above, or some foreign material in your oil.
 
What rpm range did it happen at? Baffling would be my concern in the 8v counter flow , no baffling = blown motor. Oil galley plugged to bearing? Did u blow air through the galleys and check for debris? Oil coolers are great regardless of some people's opinions, I have been runni g turbo'd vw's for years on track. Always with an air to oil cooler and Mocal t-stat.
 
Gen1, How much boost do you run on track? I am building a Chumper boosted to about 10#, I hope , T 3/4 From a merkur.
Hope that it last .
TIA, MM
 
On the internal gate with spring only I run 12 lbs, with the solenoid activated it goes to 16 lbs. u need to run the mOst efficient intercooler you can buy. Garret cores are the b est and cheapest. The trick is to get your airflow over the radiator clean, the airflow over the intercooler must also be clean air that hasn't seen the radiator or any other heat transfer device in the car. Otherwise intake temps climb and then your rad temps climb, so you'll only get 20 minutes before you start to overheat. Once I got everything in its own airflow path I could run the car all day on track. Provided you brought enough fuel with you. ;-)
Always happy to share my exp with turbo track cars. Pm me if you need any detailed info or pictures.
 
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Follow-up: Removed the after market oil cooler and went with the OEM unit. Oil pressure was excellent all weekend. Racing in 90+ degree temperatures last weekend the engine temperature never went much over 160. FWIW we are using the Bosch oil filter.

So, don't know about the quality or installation of the after market oil cooler that was on the car, but we certainly don't seem to need it.

Thanks for all the help!

Dave
 
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