Coolant Type for Subaru EJ20 Engine Conversion

[Basilakios]

Another week and another new problem to deal with.

I've not had this T25 campervan for long and barely driven it anywhere due to an ongoing issue with the gear linkage.  I've managed to fix it to a point where I could at least get it MOT'd (which it thankfully passed) but in driving to & from the garage (about a mile drive) I noticed an issue with the coolant / temperature.  

It's a 1985 T25 with a Subaru EJ20 NA engine converted for the previous owner by Mac VW (who I understand are not trading anymore) about 5 years ago.

I'm in the process of trying to fix two issues - probably related but possibly not:

The first is the temperature light is continuously flashing right from the turning the engine on.   My suspicion is the issue is at the relay as I've  been having electrical issues due to poor contacts on the fuse box thanks to a leaking windscreen which I need to get sorted when funds allow.  The coolant level is fine (or at least was).

The second issue is the engine is overheating (although I'm not sure where the needle usually sits).  I ran the engine at the weekend and the thermostat didn't appear to be opening so I've removed it and ordered a new (genuine Subaru) one.  
I of course lost a bit of coolant in doing this although I managed to capture some of what came out.  I was surprised though to see that the coolant was pink when I was expecting it to be green or blue from what I've read on the RJES website (if anyone else has a Mac VW conversion I've be interested to know if they used RJES parts and systems?  Any information would be appreciated).  
Should the coolant be pink?  Or am I right in thinking it should be the Subaru Super blue coolant? 
I'm guessing I shouldn't mix them but is it wise to flush and replace the coolant? 
 

[cobblers]

You probably can't rely on your temperature gauge - Even on an OE VW setup, the needle will usually read 2/3rds up the dial at normal operating temp. On top of this, your temperature sender might not be electrically compatible with the vw gauge.

Short of installing an aftermarket gauge, a good way to give yourself a decent idea of how the system is running is leave it idling til the fans kick in (maybe borrow an IR thermometer to keep an eye on things) and make a mental note of where the needle on the needle sits and use this as your "it's a bit hot" benchmark.

Use whatever coolant subaru recommend, the engine is the "sensitive" bit. I wouldn't hurry to change it, but it'd be a good idea to swap it, particularly if you don't know when it was last changed.

[Basilakios]

Thanks.  Once I've figured out the over-heating issue (if indeed it is overheating) I'll think about replacing the coolant with the right blue stuff.  For now I'll not worry too much about it.

I'm aware the temp gauge isn't objective but it was creeping up well beyond the 2/3rds or even 3/4 mark.  Annoyingly I don't have an idea where is should sit but as you say I'll have to mentally note where it should be once I'm confident its working right.

I should check the fan is working (again potential electrical issues).  I saw a video of someone unplugging the fan and testing it with a scrap of copper wire.  Might do that.

[multisi]

You dont need to change the coolant type just use the same colour to top up .If the conversion was done correctly the subaru electrics should be compatible for the vw temperature gauge. Was the conversion done using RJES parts, show us a photo of the engine bay.

[Basilakios]

You dont need to change the coolant type just use the same colour to top up .If the conversion was done correctly the subaru electrics should be compatible for the vw temperature gauge. Was the conversion done using RJES parts, show us a photo of the engine bay.

Is it possible to identify from this photo?

What doesn't give me confidence is that orange propane/butane pipe.  Only noticed that at the weekend along with another pipe that was missing altogether.

[pkrboo]

Yep that's rjes kit, the orange pipe is the fuel return by the looks of it so yeah, not ideal!!

Coolant will be VW pink stuff, which is fine.

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[slowcoach]

Same engine as I have, I use pink OAT coolant. So don't worry about that. Need to change mine really, it's been years.

Have you got two green multiplug connectors (unplugged) but next to each other somewhere? Perhaps under the bench seat, if there's any engine wiring there.

They are the diagnostic plugs. If you connect them together (male and female), and then ignition to on, it will test cycle the fan, fuel pump, and a few relays.

Read up a bit on the green plugs though, been a while since I used them!

Thermostat takes a surprisingly long long time to open at idle in my experience.

My temp needle is always about 5/8ths up.

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