VR6 Mocal cooler boys - show us your temps!

[Kevin Bacon 5]

Winter is drawing in again and my oil is struggling to get over 80 degrees by the end of a 10 mile journey. After a long hour + journey on the motorway, it rarely goes over 92.

 

If I disconnect the mocal and run the standard heat exchanger, the usual 114 deg at 80 mph problem comes back immediately :roll:

 

Has anyone tried blocking off their Mocal over the winter with some foil tape or something? What sort of temps do you see?

 

Going forward, would an R32 heat exchanger be a good compromise. What's the reason it won't fit in a corrado? Fouls the front engine mount or something IIRC? Any fixes for that?

[coullstar 0]

Im getting the same temps as you. They really do work effectively. Its take an age for mine to even start registering. I never really noticed until I started watching the Mk2 oil temp ad it rose very quickly.

[Kevin Bacon 5]

Yeah. I'm seeing some scary oil pressures because of my 10W/50 synthetic not getting hot quickly enough. I have to join a motorway 2 mins from cold and give it some stick because the slip road is about 10 yards long.

 

I think over the winter I might just remove the Mocal sandwich plate, wrap it in a bag and leave it tied to the engine ready for the summer, and just go back to the OE cooler.

[Supercharged 2]

Bagging its not a bad idea as they corrode like fook too... you could almost do with a bypass type arrangement.

 

Other thing to consider is a fully closed original grill and maybe different oil?

[poll250 0]

If you have the thermostatic sandwich plate, the oil won't get into the cooler until it's warm; in which case I'd be tempted to put something infront of the cooler to block the airflow through it, unless it's directly infront of your radiator that is!

[swiftkid 1]

Was going to say, have you not got a thermostatic sandwich plate fitted? I would imagine that would be best of both worlds.

[fla 9]

good thread as i was just thinking about this myself. Foil might be agood idea i guess - managed to get some slow town driving which took oil up to 90 :cuckoo: and managed to get water to about the same, perhaps a little less. I was using the aircon too to demist the car but this cooled the water too much. Stuck on 70 on the motorway, and thats with a new VW stat :shrug:

[leeeeshad 0]

I take it none of you are using the mocal thermostat then? I dont know why they even sell a kit without one.

[Supercharged 2]

Yeah I think most people do get the sandwich plate - I know most people on here bought the kit from Stealth as they were the only ones that provided the correct bits for the VR - they still just run too cold in the winter though...

[The_Dude 0]

I actually found last winter that the faster I went the colder my oil got. I do remember one trip where I had to keep slowing down to 60-70 mph to let it heat up again! Normally it'd be around 90ish degrees.

Blocking it off you'd have to use something that doesn't melt obviously and yeah they do corrode like a corroding thing. Mine lasted just under 2 years sat in the wheel well. Tried to get the hose off and the whole fitting snapped clean off :(

[dukest 0]

will be out driving in the cold later so will let you know what mine manages

[CorradoVR6-Turbo 0]

i used to cover 3/4's the cooler with plastic lid that i robed from my lunch box,cable tied it on and it really improved the temps as well as warm up time.

[g60jaime 10]

I don't think I'm wrong in saying that the reason you see all the older london black cabs with cardboard over the grille is to get the running temps a bit higher. Could do a similar thing over the cooler as previously mentioned.

[VR6cramp 0]

Good thread, am looking at fitting a mocal oil cooler to mine when i do my R32 conversion this winter as the R32 original oil cooler does not fit. What cooler did you guys get to fit urs? as i am unsure what kit fits! Any help would be appreciated :?

[h6 vwc 0]

I used a mocal non thermo sandwich plate and 13 row cooler mounted behind the front bumper bottom grill, but my mfa doesnt work obviously after the conversion....really need to wire a gauge up. The r32 heat exchanger fouls the front mount bracket. I got mine to fit by cutting the bracket down and re-welding in braces , but the material i removed was too much and on an agressive launch the engine slipped forward breaking the bracket and piercing the cooler........by the way i vagcommed my car yday and after 15 mins driving my idle coolant temp was 96 and then the fan kicked in.....is this normal.........

Also would the r32 see higher oil temps due to the fact it runs a leaner mixture until under W0T?? Thanks

[Kevin Bacon 5]

R32s run at 96 normally, which is what I like to see as well. You need to get the oil hot enough to evaporate the warm up moisture. I tend to get mayo on the filler cap this time of year, but it's defo not HG related!

Golf VR6s run the same but they have a bigger rad than Corrado.

 

And yep, just to confirm, I am using the Mocal thermostatic plate, which starts to open at 70 deg IIRC. If anything, a 90 deg opening would be a better long term solution?

 

I whipped the cooler off earlier, so I'll let you know the temps I see on the way to work tomorrow! I replaced my rad and water pump last year, which usually helps the oil temps.

[mimjed 0]

wouldnt it be easier if you had a join fabricated?

 

just a hollow metal tube with the correct thread to join the hoses, so the mocal is doing nothing if you get me?

 

i assume they will be made as plumbing parts.

[buttles 0]

Just whatever you do DON'T blank off the unions out to the heat exchanger. The thermo plate actually closes a bypass valve to force flow through the exchanger. The path out to the exchanger is free to flow at all times. It's a fail safe incase the thermo valve fails. Since going Turbo my temps have been higher under normal driving even with a Mocal. Yet to fathom out why.

[Kevin Bacon 5]

/\ Yeah that's inteteresting. My VRT runs the same temps as stock. Ball bearing turbos add very little heat to the oil, if any at all. I can't see journal bearing turbos being any different either tbh.

 

Is yours spacer plate or forged piston? If the former, I hate to ask, did the cam timing go OK? Sometimes the spacer thickness clocks the cams round a couple of degrees. Some people clock the intermediate pulley round an 1/8th turn to compensate, but other engines seem to line up OK.

 

Mimjed, good idea. I don't know about other people's cars, but the mocal on mine only takes 30 mins to remove :D

 

Well, Mocal off and the oil was at 92 by the time I got to work and water was 84 degs. Better than the 80 deg I saw yesterday! And just as importantly, the pressure was the proper 2 bar it should be at idle, instead of the 3 bar I normally see with the mocal.

 

I left it idling for a couple of minutes and the oil temp dropped to 90 and the water rose to 88, so I would say that is pretty effective heat exchange going on there?

 

I took the Mocal off a couple of years ago for the same over cooling / pressure reasons and got 114 deg @ 80mph very quickly. This time round it clearly didn't and I can only put that down to the new radiator, water pump & heat exchanger I put on last summer (VAG items). More efficient cooling and therefore better heat exchange.

 

I will monitor it. If the temps stay sensible without the cooler, I'll leave it off permanently. I will also look into fitting the 24V heat exchanger as I think that is the best compromise. If the R32 can run at

[buttles 0]

Before the Turbo conversion (and Mocal) my water was at 85 and oil 95 on a summer motorway run. After, (with Mocal) the water was very quickly going up to 100 and oil was 115. I did have a new thermostat fitted so maybe my old one was running cool? With ambient temp now around 8deg it behaves like a summer day. I had the Stealth Turbo Stage 1 done so spacer plate. I will ask Vince of the chances of slipped timing but really recon he will have covered that.

[herisites 0]

Kev, I've still got my original R32 oil cooler if you want to try with that? :salute:

[Kevin Bacon 5]

Before the Turbo conversion (and Mocal) my water was at 85 and oil 95 on a summer motorway run. After, (with Mocal) the water was very quickly going up to 100 and oil was 115. I did have a new thermostat fitted so maybe my old one was running cool? With ambient temp now around 8deg it behaves like a summer day. I had the Stealth Turbo Stage 1 done so spacer plate. I will ask Vince of the chances of slipped timing but really recon he will have covered that.

 

Timing is one thing Vince gets spot on, so you can forget that as the cause then.

 

Interesting the temp jumped up so much *after* the Mocal :scratch: Have you tried removing the Mocal to see if goes back to how it was previously, or if it runs even hotter?

 

That will tell you one of two things:-

 

1) The mocal is the cause of the over heating

2) Your engine is overheating and the Mocal can't lower it any more than 115.

 

1) is unlikely unless it was fitted incorrectly.

 

2) is very likely if the water pump is worn out, or the rad is silted up. How old are these parts? Does the water get to 100 very quickly? For reference, my 84 water and 92 oil this morning took about 15 minutes from stone cold. It could also be that your old stat was stuck open as you say.

 

Is your car a MK3 Golf? 95 oil temp in a Corrado VR6 during the summer sounds a little low :D

 

Kev, I've still got my original R32 oil cooler if you want to try with that? :salute:

 

Good man! Got any jobs that need doing? I'll grab that off you next time I'm up :D

[herisites 0]

Kev, I've still got my original R32 oil cooler if you want to try with that? :salute:

 

Good man! Got any jobs that need doing? I'll grab that off you next time I'm up :D

 

Email coming your way dude ;)

[buttles 0]

Yes, would be very surprised if timing out. New rad, main pump and several flushes. Heat exchanger gets hot so oil getting there (as above, oil has to get there cold or hot). Oil in summer was more like 100C. But very rarely got much hotter even on a hot day. Was surprised to see 115 on the drive from Stealth :eek: Ah forgot, Corrado VR6

[Kevin Bacon 5]

Hmmm, that's really odd and I'm out of ideas!! Well, there is actually one thing that crosses my mind. The angle of your intercooler. Is it perhaps partially impeding flow to the radiator? I'm sure Vince would have thought of that but it's worth checking with the other chaps who have the Stealth kit fitted to see what their temps are? I noticed on the VR6 Air con rad (i use it as the water rad for my chargecooler), VW went to great lengths to ensure the two rads align perfectly as to not impede air flow. I would be surprised if it's that, but you never know! Just thinking of things that have changed since going turbo.....

 

Well, I went out for a jolly jape at lunchtime for 90 minutes, 45 of which sat at 85-90 mph and the hottest the oil got to was 98. I'm happy with that, so the Mocal is staying off for now.