Running without oil cooler - PeachParts Mercedes-Benz Forum

m1tch · #1 06-27-2015, 10:49 AM

Hi all,

I have found another bodge on my car, it seems that whatever took out the nearside of the intercooler might have also taken out the oil cooler on that side.

When taking the inlet manifold off I noticed that there was a random hose always in the way, after removing the inlet manifold I found that the hose goes from the bottom of the oil filter, though the hose and the back to the oil filter - I am guessing that this should have gone to the oil cooler but its just been bypassed.

Would this cause any issues at all (apart from always getting in the way!) I am in the UK so its rarely hot here, still need to sort out the thermostat on the engine but now more concerned about the oil cooler.

Thanks in advance!

t walgamuth · #2 06-27-2015, 10:52 AM

The cooler would come into play if weather is hot and or a long high speed drive. If you do that much you might want to hook it back up.

m1tch · #3 06-27-2015, 10:55 AM

Hmm I will have a look into perhaps an aftermarket one, really not wanting to take that inlet manifold off again though, the 1 bolt underneath is a really stupid idea especially as you have to line everything up whilst under the car to get the bolt though the inlet manifold, pipe and bracket!

Technically there is some cooling as there is some metal pipework, however I don't really drive in hot weather or do high speed long drives - only do shorter drag runs with it, however will be bolting on a larger turbo which would require better oil cooling.

Stretch · #4 06-27-2015, 11:24 AM

For your drag racing plans I'd have thought an oil cooler would be necessary - depending on the space you need for other stuff you might actually want to upgrade from the original

mach4 · #5 06-27-2015, 11:58 AM

Mercedes generally over-engineers things, so you might well be OK. However, it may well be part of the engineered cooling of the overall system. You may find it easier to install an oil temp gauge and monitor the actual temperatures in the sump.

Personally I wouldn't run without an oil cooler without a gauge.

Another thing to consider is that the oil cooler and lines contain the better part of a liter of the oil in the system obviously change intervals should be shortened if not present.

Stretch · #6 06-27-2015, 01:04 PM

...and I don't know how the OM606 oil filter system works but if it is like the OM61X version then I reckon just blocking off the lines can cause the system to think that the filter is blocked and so it goes to "emergency mode" and pushes unfiltered oil back into the engine - straight into the crank and the plain bearings etc etc etc...

97 SL320 · #7 06-27-2015, 01:35 PM

Has the 61 system actually been mapped out to confirm that blocking cooler lines will bypass the filter? The cooler can tolerate a higher pressure drop than the filter as the filter will crush.

For engines in general, the filter and cooler bypass are separate. It is common on a cold day for the filter bypass to open because the oil is too thick to pass through the media.

For the cooler, either a thermostat or a bypass is used. The pressure bypass acts as a low rent thermostat. When thick / cold oil can't pass through the cooler the bypass opens.

Dan Stokes · #8 06-27-2015, 01:52 PM

I looped my inlet to the outlet on my race-only OM617 (I do 1 mile Land Speed on pavement at the ECTA track in Ohio). So far so good. I have a number of runs and while I don't have an oil temp gage yet nothing gets hot to the touch and the June meet had pretty warm ambient temps.

I have ZERO experience with your engine, however, so take this as one limited data point.

Dan

m1tch · #9 06-27-2015, 02:30 PM

I will look to get something installed, I thought it was rather odd that there was a hose that got in the way of basically everything - will check out some options but will probably look at getting a Mocal one with a thermostatic valve.

PARSHOOT1 · #10 06-27-2015, 08:28 PM

I might have missed it, but did you say what kind of shape the hoses were in? Also, for my OM602 the only coolers available were OEM and ran between $300 and $400. Not sure whether you'll find the same for your engine, but I'd be willing to wager. And your description of it being a PITA is the feedback I got from the indy mechanic I worked with on the job. I think his words were "don't bring me another one of those for awhile"!

m1tch · #11 06-28-2015, 06:57 AM

The hoses are in an almost new condition, I have been very lucky with my car as it seems that its been well looked after in terms of the condition of most of the parts. The car has had 2 previous owners, I have a feeling that the 1st owner looked after the car properly and bought all of the proper parts. The 2nd owner might have cut some corners especially after it seems that there has been some damage to the nearside of the car with regards to the intercooler being damaged and the oil cooler being disconnected.

Does anyone know what the standard fitting sizes are on the oil filter side?