TheSamba.com :: View topic

Sun Nov 06, 2022 7:57 am

old_man wrote: FunkyOldPatina wrote:
So it's basically a spark plug hole cover (piece of tinware) then from the looks of it, that the spark plugs stick out of?

Spark plugs don't stick out. It, just like all the other tin, is important. It helps force cooling air through the cooling fins of the cylinders. If you don't have that piece, air will escape.

Thanks very much, didn't know this part existed until a couple of days ago :-)

Tinware seems very hit and miss on VW's - so many seem to have missing parts.

Mon May 26, 2025 6:10 pm

So reviving an old thread. I am lost here. I inventoried all my engine tin and in looking at this picture I have everything but these items in red. What are they and where do they go?

Tue May 27, 2025 12:26 pm

I believe they are called warm air ducts. Thety mount to the cylinder tin, check the first page

Tue May 27, 2025 1:12 pm

bigwhit wrote:

So reviving an old thread. I am lost here. I inventoried all my engine tin and in looking at this picture I have everything but these items in red. What are they and where do they go?

I don't know what they're called (warm air ducts), but they attach to the upper tin pieces, and go between the cylinders and the big fan shroud creating the cooling air duct to cool the engine. You can find them on page 50 of the parts book in the technical section of this fine site. They're called out as parts 3 and 4.

Tue May 27, 2025 5:03 pm

sjbartnik - Does that mean that most of the tin in type3+4's aren't all that helpful as long as you have the boot and vent system all sealed?
thx!
-W

sjbartnik wrote: The Type 3 engine bay is open and not sealed to the body like Beetles and Buses for one reason:

In Beetles and Buses, both the cooling air and the combustion intake air are sourced from within the engine compartment. This necessitates that the upper half of the engine be sealed off from the lower half to keep the hot air that gets dumped out under the engine from recirculating into the engine compartment and being picked up to use as cooling air and combustion intake air. Hence all the tin and the seal between the tin and the body.

Type 3s get their cooling air and combustion intake air via the ducts in the body and they have a rubber bellows that connects the fan housing to the body ducts as well as a rubber bellows that connects the air cleaner intake to the body ducts. Those rubber bellows ensure that only cool/outside fresh air gets into the cooling system so in that case there's no need to seal the engine compartment to the body or to isolate the upper half of the engine from the lower.

Of course if you run a Type 3 engine without the cooling fan bellows you will overheat it.

The gap between the firewall tin and body allows for the movement of the engine on its mounts relative to the body without rubbing/scraping/transmitting vibration into the body/scratching up the paint.

Wed May 28, 2025 10:41 am

Wilson wrote: sjbartnik - Does that mean that most of the tin in type3+4's aren't all that helpful as long as you have the boot and vent system all sealed?
thx!
-W

All of the tin is needed to properly direct the airflow where it needs to go. Type 3/4s are just different in that they pull the source air through the bellows/fenders from a spot away from the engine. That removes the requirement of having a sealed engine bay like Bugs/Buses.

Thu May 29, 2025 11:54 am

Joe - Sorry, but your that sentence seems a bit unclear..

"All of the tin is needed to properly direct the airflow where it needs to go" but also "That removes the requirement of having a sealed engine bay like Bugs/Buses."

From the factory, the engine bay was sealed, correct? If the T4 is the outer tin (parts that connect to the inner bay body) more for appearance?

Thx,
W

Thu May 29, 2025 1:50 pm

Wilson wrote: Joe - Sorry, but your that sentence seems a bit unclear..

"All of the tin is needed to properly direct the airflow where it needs to go" but also "That removes the requirement of having a sealed engine bay like Bugs/Buses."

From the factory, the engine bay was sealed, correct? If the T4 is the outer tin (parts that connect to the inner bay body) more for appearance?

Thx,
W

For Type3/4, air enters the fan through the bellows (which pulls in air through the fender vents). The air is pushed across the top of the cylinders towards the front of the car. It then loops down and around the bottom of the cylinders, now going to the rear of the car and out. The bellows essentially act as the seal between the hot and cold air zones. There were no other tins/seals between the engine and body to restrict air movement.

Whereas bugs and busses have tins and seals that physically separate the top and bottom half of the engines to keep the distinct hot and cold areas separate. Remember that the Type 1 engine fan just pulls in air from the engine compartment itself (which has some venting to pull in cooler air).

Hope that helps.

Thu May 29, 2025 2:00 pm

Yes Joe, that helps a lot thanks! I've seen some type 4's where the tin goes all the way across, but I think those have all been hand-made.

Cheers,
W

Thu May 29, 2025 3:34 pm

gtixpress wrote:
For Type3/4, air enters the fan through the bellows (which pulls in air through the fender vents). The air is pushed across the top of the cylinders towards the front of the car. It then loops down and around the bottom of the cylinders, now going to the rear of the car and out. The bellows essentially act as the seal between the hot and cold air zones. There were no other tins/seals between the engine and body to restrict air movement.

Whereas bugs and busses have tins and seals that physically separate the top and bottom half of the engines to keep the distinct hot and cold areas separate. Remember that the Type 1 engine fan just pulls in air from the engine compartment itself (which has some venting to pull in cooler air).

Hope that helps.

That's a dynamite explanation for people who are used to bugs and buses,or ghia's and Things (and why they have tin all around the engine) but are not used to how a type 3 is cooled, and why once the engine is in place it has all of those spots where you can see the ground looking around the engine (not sealed to the body by tin). Thanks Joe for explaining it in clear English. 8)

Fri May 30, 2025 11:29 am

Glad it helped!