Good idea, or not?

[Pond]

I really need to check all is well with the engine in my Z3 so want to get it started. It hasn't been run for six months.
I can't get it outside easily, so want to run it in the garage. I don't want to be suffocated so I thought I would put a length of flexible ductwork (8" dia) on the exhausts and route the duct to outside (about 10 feet). It won't be fan assisted but will be pretty flat on the floor.
Is this a good idea, or could there be issues with gas build-up in the exhaust due to the duct?

 

[hard top]

I have seen it done at a couple of local garages and from what I can remember, they used something like this :-

Vehicle Exhaust Hose System
Link :- https://exhaustaway.com/blog/how-vehicle-exhaust-hose-systems-keep-workers-safe/

 

[Duncodin]

An 8 inch tube placed loosely on the tail pipe isn't going to extract everything. Fumes will take the path of least resistance so much of it won't want to go down the pipe.

But I have done it when working on an engine and needed it to get warm. The tube needs to be fat. 8" should be ok. Needs to be attached snug with no gaps and anchored well because it will pop off if it can. forcing the fumes into the tube then you should be good.

Having said that. I wouldn't bother if you're just curious about the engine. I'd just open the garage door and a window, if there is one, and run the engine just for a couple of minutes at the most. I'm not sure there's any benefit in running it for longer.

 

[Pond]

I will fasten the duct tight to the exhausts. No leaks otherwise it's pointless.
I know about ventilation but I don't know about cars' exhausts and stuff.

 

[Zephyr]

Be very carefull, it may get very hot. I have seen such a setup during a dyno run and the person in charge used gloves to remove the gas hose.

 

[motco]

I really need to check all is well with the engine in my Z3 so want to get it started. It hasn't been run for six months.
I can't get it outside easily, so want to run it in the garage. I don't want to be suffocated so I thought I would put a length of flexible ductwork (8" dia) on the exhausts and route the duct to outside (about 10 feet). It won't be fan assisted but will be pretty flat on the floor.
Is this a good idea, or could there be issues with gas build-up in the exhaust due to the duct?

Mine isn't run for many weeks at a time currently, for various reasons. But when it is, provided that the battery is charged, it starts as if it was run only yesterday. I did have a Westfield up until a few months ago that hadn't run since about 2015 - Ford Pinto SOHV with two twin choke Dellortos - and that really was a challenge! Good Luck!