Technical Panel behind radiator

[Badget]

I had planned on something similar but placed under the passenger footwell, again using the heating circuit.

I think the problem you maybe having us that the heat lost this way is then funneled through the radiator so in effect you could be pre heating the cooling air.

I know a lot of the subaru converted t2's use a flat belly mounted rad to good effect but most of these are in Australia or California and aren't subjected to the delights of Uk roads.

 

[Classicandy45]

I had planned on something similar but placed under the passenger footwell, again using the heating circuit.

I think the problem you maybe having us that the heat lost this way is then funneled through the radiator so in effect you could be pre heating the cooling air.

I know a lot of the subaru converted t2's use a flat belly mounted rad to good effect but most of these are in Australia or California and aren't subjected to the delights of Uk roads.

I also have a problem with the original heater circuit... I think I split a heater pipe as I suddenly developed large leaks under cab floor. Upon investigation, I discovered the pipes are plumbed inside the floor cavity, meaning complete removal of camper interior to get at them, so I simply disconnected and isolated the heater pipe system ( bypassed)... this cured the leak, left me without a heater but more importantly deprived cooling system of a rather large amount of coolant so I think that 'bodge' has a lot to do with my problems. Would love to fit front mounted rad, but routing the plumbing is rather a conundrum!

 

[Classicandy45]

I suppose if you are at the bare shell, restoration stage, it would pay dividends to ensure the heater pipes are effective and reliable!

 

[FR85]

Having had a think about cooling issues on the 850 and 900 vans, the berlina/sedan pulls cool air across the engine from left to right, the lower panel that also supports the engine has two vents both left and right but the right one is channeled to the left and outside air is drawn in here, across the engine all being pulled by the fan. On the Van's you have two vents either side of which the right side I'd imagine is pulling in the most air being closest to the fan so the left side may not be getting a look in. There are vents on the engine boot lid of the cars but I see a lot of folks on insta and fb seem to have these covered, could be to keep rain out or maybe they know something we dont. Could it be worth temporarily blocking the right side vent and running an experiment to see if drawing ram air for want of a phrase across the block will aid with cooling? I've done the cigarette smoke test and that little vent on the lower left corner pulls in a lot of air.

 

[FR85]

On the cars this panel appears to be one piece and part of the bulkhead
On the vans the lower portion is a separate, bolt on shroud though it looks very similar once bolted on.

Mine is entirely missing, though I can't see how the panel in question would have much influence on airflow below the car/van.

I've spent hours trawling through restoration threads and pictures and have never seen another with this panel fitted.

Its actually quite clever, as a car drives along it pushes air around, over and under itself, as this air passes below there is a vacuum effect and it sucks the air that is being blown out from the rad away, that panel below just introduces your warm cooling air into the passing air. Similar to standing in a subway as a train passes through, you get a build up of air being pushed in as the train approaches and then a hoover effect as the train leaves.

 

[Badget]

The left side vent feeds the engine air intake, or at least thats the side it's on.

It's also over the exhaust.

It seems perculiar to me that the design would rely so heavily on the vehicle actually moving, I mean even in the sixties the cities of northern Italy were rammed, not to mention much hotter than the UK.

Fiat sold loads of these vans all across the continent so the design must have been satisfactory, it's not like it had a short production run either.

I know a lot of vans are missing various shrouds and ducting but there are no shortage of people who have spent considerable amounts in both time and money to no avail.

Not to mention none of this explains the seemingly extra panel on my van.

 

[Gary50]

Hi,
Just spotted this thread.
As already confirmed, the air is drawn in through the side vents (louvres) and then pushed through the rad to exit under the engine bay. The panel in question (looks like a scoop fitted in reverse with a couple of holes to the sides) acts as a baffle to reduce the risk of air back flow when driving forward.

It's important to have the engine 'floor' panels in place to prevent the air recirculating into the engine bay. While driving this works okay but if you get stuck in stationary traffic the hot air inevitably fills the engine bay.

If you see my thread on Connie here you can see how I've built additional ducting to take the hot air beyond the rear. I've kept the holes in the scoop as this acts as a ram effect to push the hot air through when driving.

If you look at my thread you will also see how I've fitted a couple of electric fans, one just in front of the rad (inside the cowling, between the rad and the normal fan) and the other behind the offside vents. I had hoped to dispense with the standard fan but without it the electric fans were running all the time.

The set up works really well... you get burnt legs if you stand behind the van when fully up to temperature and all (3) fans are running.

You will also see that I've fitted a 4-branch exhaust, this meant the old 'dustbin' air filter wouldn't fit. So I've fitted a piece of stainless steel tubing from the rubber gaiter on top of the carb and a K&N filer on the other end so that it draws cool air from the near side vents. I won't be using the van in winter so the cold running option (taking hot air off the exhaust) isn't needed.

I've also added an electric fuel pump and upgraded to 123-electronic ignition. The problems with hot starting are a thing of the past... it was really embarrassing having to wait up to an hour a fuel pumps for Connie to cool down and clear the vapour lock before she would start again.

Note: I've only had a couple of runs with her since I got her back on the road, after having the engine & rad sitting dry for a few years. Even though I flushed the cooling system several times before refitting, on the last run the cabin heater stopped working. I think getting her running back up to temperature for a good run has loosened all the rust and gunk inside and clogged up the cabin heater matrix. My first job this year (before I carry on with the restoration) is to flush everything out again.

Hope this helps.

 

[Badget]

Hi Gary
I think there maybe some confusion here.
The panel in question isn't the underbody reverse scoop pictured earlier but an additional panel pictured in the first post.

I've never seen another van with one and can't figure out what it's trying to do
On the other hand it looks a little too good to be a home made add on.

Once i get to the back end and remove the radiator I'll post some more pictures of it.
Just the small matter of a rotten chassis leg and a suspension rebuild before that.

 

[Gary50]

Hi,
Just spotted this thread.
As already confirmed, the air is drawn in through the side vents (louvres) and then pushed through the rad to exit under the engine bay. The panel in question (looks like a scoop fitted in reverse with a couple of holes to the sides) acts as a baffle to reduce the risk of air back flow when driving forward.

It's important to have the engine 'floor' panels in place to prevent the air recirculating into the engine bay. While driving this works okay but if you get stuck in stationary traffic the hot air inevitably fills the engine bay.

If you see my thread on Connie here you can see how I've built additional ducting to take the hot air beyond the rear. I've kept the holes in the scoop as this acts as a ram effect to push the hot air through when driving.

If you look at my thread you will also see how I've fitted a couple of electric fans, one just in front of the rad (inside the cowling, between the rad and the normal fan) and the other behind the offside vents. I had hoped to dispense with the standard fan but without it the electric fans were running all the time.

The set up works really well... you get burnt legs if you stand behind the van when fully up to temperature and all (3) fans are running.

You will also see that I've fitted a 4-branch exhaust, this meant the old 'dustbin' air filter wouldn't fit. So I've fitted a piece of stainless steel tubing from the rubber gaiter on top of the carb and a K&N filer on the other end so that it draws cool air from the near side vents. I won't be using the van in winter so the cold running option (taking hot air off the exhaust) isn't needed.

I've also added an electric fuel pump and upgraded to 123-electronic ignition. The problems with hot starting are a thing of the past... it was really embarrassing having to wait up to an hour a fuel pumps for Connie to cool down and clear the vapour lock before she would start again.

Note: I've only had a couple of runs with her since I got her back on the road, after having the engine & rad sitting dry for a few years. Even though I flushed the cooling system several times before refitting, on the last run the cabin heater stopped working. I think getting her running back up to temperature for a good run has loosened all the rust and gunk inside and clogged up the cabin heater matrix. My first job this year (before I carry on with the restoration) is to flush everything out again.

Hope this helps.

Hi
Sorry for the delay.
I've attached a couple of photo's looking up underneath my 900T with the bottom reverse scoop removed.
The panel between the radiator and body work is welded in place (from the factory) and is designed to stop air pushing through the rad when travelling forward.

The fan pushes air through the rad (against the forward motion) and out through the gap between the rad and panel. The bottom cowl then directs the hot air back under the engine bay - hence the need for the engine bay floor plates to reduce the amount of hot air coming back into the engine bay. That's where I've added the extra ducting to make sure hot air goes beyond the engine bay,

Not the greatest design from Fiat (but it was the 1970's)... it would have been much better if they had stuck the rad behind the engine cover and let the air flow naturally out the back rather than forcing a U-turn on the airflow.

Hope this helps.
Cheers
Gary

 

[Badget]

Hi, Gary50 thanks for the pictures.
The panel on mine is not in those pictures, so the mystery continues

 

[Badget]

So a full year on and I've finally got to take this panel and radiator out ready for the engine coming out this week

This is the part in question.
It's definitely a factory panel and as far as I can tell it seems to shroud the heater pipes and prevent the fan from blasting air through the channel the pipes pass through.

It's possible that it could create a pressure difference creating some kind of venturi effect but
A, thats way over my head
B, I'd be surprised if fiat put that much effort into a cooling system that seems marginal at best

 

[Classicandy45]

So a full year on and I've finally got to take this panel and radiator out ready for the engine coming out this week

This is the part in question.
It's definitely a factory panel and as far as I can tell it seems to shroud the heater pipes and prevent the fan from blasting air through the channel the pipes pass through.

It's possible that it could create a pressure difference creating some kind of venturi effect but
A, thats way over my head
B, I'd be surprised if fiat put that much effort into a cooling system that seems marginal at best

Deffo looks 'factory' but got me intrigued!

 

[Badget]

It's a factory fit alright, it even bolts to captive studs on the bulk head.