EJ22 in bay heating up too much

Obonobo · Posted: Mon May 14, 2012 1:22 pm Post subject: EJ22 in bay heating up too much

As you may have read, I MOT'ed my van recently. The 75 bay features an Subbie EJ22 from '93. I have and underbelly rad with scoop and blowing fans, no heater, and a Polo header. Fans are switched by temperature switch between 90 and 95C.

I drove it for 600k last weekend and it went moderately okay. The positive is that it didn't boil. The bad news is: but only just and it needed constant fans! I stopped a few times to check on air in the system: three times it vented air, the last time it didn't. Fuel economy is 1liter to 10 kms.

When driving until 60km/h, fans come on and off, so temp is about 90C. Likewise for stationary running.

But, contrary to popular belief, temperature rises when driving faster than that. I cruised about 100km/h constant, but fans had to come on within 10mins and stayed on for the duration of the trip. Again, it didn't boil.

I begin to fear that the cooling may be okay, but there's something wrong with the engine.

I checked for goo in de oil filler cap, to see whether there's coolant in the oil, but none to be seen. Level of coolant doesn't drop overnight, either.

Does anyone have any suggestions where to check for what?

Thanks!
_________________
Greetings from Sietze
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Driving a '75 Bay with a EJ22 '93 and 091 6-rib box.

And it's a long time since it looked anything like this!

steamo · Posted: Mon May 14, 2012 5:46 pm Post subject:

Sounds like the same issue as I'm having. I'd say that there is no issue with the engine. All cars take more cooling at high speeds as the engine is working harder. On a normal car with the rad up front there is no problem with cooling as the airflow through the radiator increases with speed hence providing better cooling.

The solution is to improve the airflow through your radiator, I've got a air scoop to fit at the front of mine with ducts which will feed cool air to the top of the radiator (which is boxed in) this creates high pressure air above the radiator. The faster moving air below the radiator is at a low pressure. It is this pressure difference which will generate air flow throught the radiator cores.

Hope it helps.

Obonobo · Posted: Mon May 14, 2012 6:18 pm Post subject:

Thanks Steamo, that is a bit of a consolation and reassurance: I am really hoping it doesn't have anything to do with the engine itself.

But I will play around with the scoop and change the location of the fans. They are now on top of the rad, and might therefore be in the way of the airflow.

I think I will go forward with putting them underneath and trying to duct air directly from the front.
_________________
Greetings from Sietze
-------
Driving a '75 Bay with a EJ22 '93 and 091 6-rib box.

And it's a long time since it looked anything like this!

steamo · Posted: Mon May 14, 2012 8:00 pm Post subject:

Here are some old pics of my setup which I made ages ago I've changed the radiator since but the idea is still the same.

I havn't actually fitted this yet but plan to very shortly as I'm experiencing the same cooling issues as you.

Obonobo · Posted: Mon May 14, 2012 8:06 pm Post subject:

Hey Simon, I made your pics visible, for easier viewing. I think I will try something similar. If you get round to it quicker, please share the results. Nice van, by the way!

_________________
Greetings from Sietze
-------
Driving a '75 Bay with a EJ22 '93 and 091 6-rib box.

And it's a long time since it looked anything like this!

steamo · Posted: Mon May 14, 2012 8:20 pm Post subject:

Cheers for that I don't know what I did wrong that time. It'll be the weekend before I can give it a try as I'm away for work this week but I'll keep you posted as soon as possible. Both our rad setups seem very similar so what works for one should work for the other in principle

Liking your van to. Wish I could have afforded to go down the scooby route myself.

Superleggo · Posted: Mon May 14, 2012 10:37 pm Post subject:

Obonobo - Just a thought are you restricting your air flow by using the red pipes. Why pick the air up at the front when you can pick it up underneath? Round pipes are 25% less area than a square section so the flow is reduced and also the pipes will slow the air up as well.

A simple scoop in front of the rad will scoop up a greater volume of air which may help.

I have not run mine in anger yet but most people say the top down theory works.

Obonobo · Posted: Tue May 15, 2012 6:24 am Post subject:

He, Superleggo.

The pics are from Simon's van. These are mine:

Fans are inside, blowing down:

I am planning to put the fans underneath and have them sucking. I think they restrict airflow through the rad this way.
_________________
Greetings from Sietze
-------
Driving a '75 Bay with a EJ22 '93 and 091 6-rib box.

And it's a long time since it looked anything like this!

steamo · Posted: Tue May 15, 2012 8:44 pm Post subject:

Supperleggo may be right, its definately something thats crossed my mind. My logic was that the by the time the air under the van had been disturbed by the beam etc it might nit be as effective as the uninterrupted airflow from the front (of course my scoop and pipes may disturb the air worse). Also I was a little worried about space initially as my van is loweted.
I think I'll fit the pipes as its only a 5 minute job and see if it works. If not it'll be back to the drawing board for a scoop as per supperleggo's description. If I hadn't already made the scoop I'd probably go down that route straight away. Especially as I've not lowered my van as much as I'd originally planned.

Superleggo · Posted: Tue May 15, 2012 8:51 pm Post subject:

Obonobo

Sorry for the confusion reading too many links fter the pub! I can't see much wrong with you cooling setup in fact I have just copied your idea of the mesh on the front of the scoop as I thought it was a good idea.

I am not convinced that the position of the fans will make much difference at speed. I have only put mine below on the basis if I hit the fan I may get home but if I hit the radthen the AA are involved!

I assume you have not got an air lock in the system. I had big problems on a Renault 21 once which was a sod to fill. Just thought but I am not expert on your engine.

Obonobo · Posted: Wed May 16, 2012 8:33 am Post subject:

I will give it a try without the fans in the scoop: when looking in it, the area 'blocked' by them is quite large. The reason I think this is that FellowSpeedshop has a scoop slimmer than mine, forcing air bottom to top with fans on top of the rad, which is also smaller than mine. And they sell it to people, so I assume it works properly.

Plus, I will round of the rear upper angle, which is very square now, to guide the air a bit better. It is a fairly easy upgrade, so worth the effort, I suppose.

If it doesn't appear to work, I'll enlarge the scoop. Widen it maybe.
_________________
Greetings from Sietze
-------
Driving a '75 Bay with a EJ22 '93 and 091 6-rib box.

And it's a long time since it looked anything like this!

Obonobo · Posted: Fri May 18, 2012 5:22 pm Post subject: Hurray, fixed it!

I think I got it!

Today I mounted the fans underneath the rad, which leaves a lot of space in the scoop. I had to reroute the electrics, but that was easily done. Because the rad hangs in an angle (front edge down), the fans are not the lowest point: convenient!

I put the kooling to the test: drove 110km/h, at 3500 rpm and temperature stayed below 90C, more like around 85C. WHen I entered a village it went up and gradually sank again to 85/90C without fans coming on, when I drove 5 min around 60km/h. When stationairy, the fans come on and kool it to 90C.

Passed!
_________________
Greetings from Sietze
-------
Driving a '75 Bay with a EJ22 '93 and 091 6-rib box.

And it's a long time since it looked anything like this!