Technical Thermostat housing

[usafstud]

Hey guys,

Got the engine running and almost all put together but the thermostat housing. How does the rod hook up to the flap?

 

[tjmra]

Your first photo shows the loose end of the rod hooked onto a bolt. Said bolt has two sides that have been machined flat.

Your second photo shows the flap with a hole in the middle of it. The hole is the same shape as the bolt on the end of the rod.

Close the flap a (against the spring tension), and pass the bolt through the flap. With your third hand, find the spring washer and nut (that I can't see in the picture) that fits the end of the machined bolt and screw it on. From memory you don't need a special bolt, not sure if a 'Nyloc' nut would be a bad thing.

When the Charlotte docks you will get a proper answer from downunder........

Joe R

 

[Bambino]

There you go .....

Chris

PS: We came over on the PoW, not the Charlotte

 

[usafstud]

Your first photo shows the loose end of the rod hooked onto a bolt. Said bolt has two sides that have been machined flat.

Your second photo shows the flap with a hole in the middle of it. The hole is the same shape as the bolt on the end of the rod.

Close the flap a (against the spring tension), and pass the bolt through the flap. With your third hand, find the spring washer and nut (that I can't see in the picture) that fits the end of the machined bolt and screw it on. From memory you don't need a special bolt, not sure if a 'Nyloc' nut would be a bad thing.

When the Charlotte docks you will get a proper answer from downunder........

Joe R

I had a feeling that was how it should be put together. But, i am missing the spring bolt and washer. Can i drive the car around without the thermostat housing for now. Outside temp is in 50's Fahrenheit.

 

[usafstud]

Where can i get the missing parts?

Mr. Fiat dont have them.

Thanks guys.

 

[tjmra]

My research indicates POW had 1 male and 49 females. How devilishly clever!

I used to know what a farenheit was but I forgot it when I learnt 'eccentrically'.

All I know now is that 50F is pretty cool (at least for a Queenslander anyway). Under normal circumstance the flap would open to let heat out. At 50F I think you would want to keep heat in to get everything to the correct temp.

Does the local autostore not have metric nuts and bolts that you can buy. Like I noted earlier, I dont think it is anything special.

Take the bolt down and see if they have something that fits.

Joe R

 

[usafstud]

My research indicates POW had 1 male and 49 females. How devilishly clever!

I used to know what a farenheit was but I forgot it when I learnt 'eccentrically'.

All I know now is that 50F is pretty cool (at least for a Queenslander anyway). Under normal circumstance the flap would open to let heat out. At 50F I think you would want to keep heat in to get everything to the correct temp.

Does the local autostore not have metric nuts and bolts that you can buy. Like I noted earlier, I dont think it is anything special.

Take the bolt down and see if they have something that fits.

Joe R

Thanks Joe. After reading my really bad quality service manual PDF, it doesn't seem to be a good idea to run it without it. I'll take it to a couple of shops to figure it out.

Another question, the car did not come with a heating duct to the cabin. Could this cause the car to run at the wrong temperature? Especially in the winter?

Thanks,
Frank

 

[Miramontesj]

I don't have the heating duct either. The biggest pain so far is during the morning when I don't have any air flow to get rid of the foggy windshield.

 

[Bambino]

Thanks Joe. After reading my really bad quality service manual PDF, it doesn't seem to be a good idea to run it without it. I'll take it to a couple of shops to figure it out.

Another question, the car did not come with a heating duct to the cabin. Could this cause the car to run at the wrong temperature? Especially in the winter?

Thanks,
Frank

Frank et al,

After the impeller picks up the inflowing air, that air is directed across the engine and also through the air filter to the carby (?? some sort of primitive turbocharging ). It is collected on the exit side where it flows freely out toward the cabin duct or, depending on the position of the thermostat vane, is either 'recirculated' or vents to the atmosphere. The absence of ducting to the cabin is equivalent to leaving the cabin valve open all of the time and really should have little effect on either warming or cooling of the engine.

I got my bits for this part of the car from a company in Germany. If you wish, I'll find out exactly where and let you know, but surely you should be able to find at least one metric nut in the land of the free

Hope you get it sorted soon.

Chris

PS: Never said that my ancestral migrant(s) was male .....

PPS: 50degF is 10degC. I visit Tasmania a fair bit in Winter and any temperature above zero is considered a heatwave .....

 

[usafstud]

I cleaned up the housing and put the nut/bolt on the the flap.

Does anything look wrong on any of these pictures? I don't know if the part on the first picture is supposed to be split/broken or not.

What is the diameter of the airduct that does on to the cabin connect? How does it connect to the thermostat housing? I hose I have lying around is a 3" aircraft hose I used to make some brakeducts.

Thanks guys.

 

[Bambino]

I cleaned up the housing and put the nut/bolt on the the flap.

Does anything look wrong on any of these pictures? I don't know if the part on the first picture is supposed to be split/broken or not.

What is the diameter of the airduct that does on to the cabin connect? How does it connect to the thermostat housing? I hose I have lying around is a 3" aircraft hose I used to make some brakeducts.

Thanks guys.

The tinware shouldn't have any splits or breaks - if present though, they should be easy to fix.

The air ducting is black 3" corrugated tubing and the stuff you have should be fine. It is connected via a curved metal duct in both the 500 and 650 (126) engines though because of the angle of the exhaust, the orientation of the duct is different for each. I've attached a couple of photos of the 500F manifold.

The thermostat flap looks good - you must have found the only metric nut in the US

Good luck with it and keep the photos coming.

Chris

 

[tjmra]

Chris,

one of the corners of the flap has a bend in it that looks like it stops it from closing completely. Mine is flat. Is this one of the differences? Also, there should be an 'L' shaped bracket somewhere there that helps hold the unit to the engine. I have included a photo of mine (pre strip, repair and repaint). One of Chris's photos also shows the bracket from a different angle.




Chris is 10% corect as usual. Because of all the vibration you need to have the cooling shrouds in good condition (no cracks, all the mounting points intact and all the mounting points used) otherwise they are just going to slowly destroy themselves.

I know this from the 15 odd years of driving mine.

Regards


Joe R

 

[Bambino]

That shroud of mine has been dinged around a fair bit so it may have a few extra curves. As far as I know, the only difference is the duct angle - the flaps are interchangeable between the 500s and 650s.

My 0.2c (10%) worth,
Chris

 

[tjmra]

Just re read my last post.

Should have been 'Chris is 100% correct' (not 10%).

Sorry buddy, nothing untoward intended.

Joe R

 

[Bambino]

No worries - I've got a thick hide to match my thick head

I panelbeat my piece of airduct and tried to fit the thermostat flap (the engine didn't have one when I bought it) last night. I've got all of the bits, but the drilled rod is too short and there is no way I can attach the return spring. Have to sit and think about it a bit.

The flap on the engine in the car is OK.

Chris

 

[Bambino]

Found these photos at

http://www.fiatclassic.com/HTML500/KATA500U.HTM#engine

They show the essential differences between the 126/500R and the earlier thermostat housing. The spring on the later housings must mount inboard somehow. When I next pull the engine out of my car, I'll have a look.

If it all gets too hard, new bits of tinware seem to be available.

Chris

 

[usafstud]

I saw the new parts from classicfiat yesterday, but dont feel like spending $200 with shipping at this time.

I'll tacl weld the crack and revit this out let i found. It should work.

What do you guys think about just weldind the outlet shut since i'll never need the heat in cabin?

 

[Bambino]

I saw the new parts from classicfiat yesterday, but dont feel like spending $200 with shipping at this time.

I'll tacl weld the crack and revit this out let i found. It should work.

What do you guys think about just weldind the outlet shut since i'll never need the heat in cabin?

You are right - the tinware is quite expensive for what it is.

Closing the vent outlet is certainly an option and probably a simpler solution than trying to remanufacture the bent metal conduit.

I like the photo with the beers in the background - good to see the priorities are correct. It looks a bit like my benchspace.

Keep up the work and the photos.

Regards,
Chris