Metal Accordion Pipe To Air Box 1998 v70 946841, 9438274

Post by **MrAl** » 10 Jan 2023, 00:11

Hello there,

I was wondering how that metal pipe/tube comes off of either the engine or the air box it is not clear how that works in the video for changing the distributor cap. I see the box pulled out, but there is no detail on how the pipe comes off or goes back on.
This seems to be an essential step in getting the air box out so you can get to the distributor cap successfully.

Thank you for any ideas.

454cid · Post by **454cid** » 10 Jan 2023, 00:26

I think it just slides off. I don't think mine was clamped in any way.

Post by **MrAl** » 10 Jan 2023, 00:57

454cid wrote: ↑10 Jan 2023, 00:26 I think it just slides off. I don't think mine was clamped in any way.

Oh ok thank you. I am just in the process of getting ready to change the dist cap and rotor and that was maybe the only thing left to deal with. I think i know how to get the air box off but we'll see (haha).

I found my old Chilton car repair book, or should i say my Chilton joke book. Here's two lines from the book where the cap and rotor are being replaced after removing the old ones, and because they always say you have to remove the negative battery cable before doing any work, it also mentions replacing the battery cable, but here is the exact wording and exact order and exact enumeration of the last three steps and there were 16 steps in all...

14. Install the air cleaner housing and hoses if removed.
15. Start the engine and ensure that it starts and runs normally.
16. Replace the negative battery cable.

HA HA. I never knew you could start the engine with the negative battery cable removed HA HA i just had to laugh when i saw that one.
Maybe the guy who wrote this had a supernatural Volvo, or EXTREME dyslexia

Seriously i think i can describe this book in a few sentences as example...
1. Remove battery.
2. Fix car.
3. Replace battery.
4. Start car.
There, you just saved 20 bucks.

Post by **abscate** » 10 Jan 2023, 05:07

Part numbers 946841, 9438274 for reference. It’s 2inch / 5 cm corrugated aluminum pipe, available as “heat riser pipe” at yourvFLAPS LIKE Advance or Autozone.

Post by **volvolugnut** » 10 Jan 2023, 06:16

The hot air pipe to the air intake has history back to the early 240 Volvos. They helped engine warm up BUT if the thermostat that regulated the air flow failed, over heated air to the intake reduced fuel economy. Most of the hot air tubes were removed over time.
Volvolugnut

Post by **scot850** » 10 Jan 2023, 09:54

When they work, they work great to the point where it would have been good to have a similar arrangement for the turbos for cold climates. Helps the engine heat up much quicker and therefore the cabin as well. The thermostat is the only downside unfortunately, and unlike the 240 is not replaceable. I think I read a thread somewhere on someone who modified a P80 NA flap to use a 240 one.

Neil.

454cid · Post by **454cid** » 10 Jan 2023, 09:59

MrAl wrote: ↑10 Jan 2023, 00:57 14. Install the air cleaner housing and hoses if removed.
15. Start the engine and ensure that it starts and runs normally.
16. Replace the negative battery cable.

HA HA. I never knew you could start the engine with the negative battery cable removed HA HA i just had to laugh when i saw that one.
Maybe the guy who wrote this had a supernatural Volvo, or EXTREME dyslexia

You have to use the hand crank, but watch out for the kick back

Post by **MrAl** » 10 Jan 2023, 13:23

abscate wrote: ↑10 Jan 2023, 05:07 Part numbers 946841, 9438274 for reference. It’s 2inch / 5 cm corrugated aluminum pipe, available as “heat riser pipe” at yourvFLAPS LIKE Advance or Autozone.

Oh that's nice to know they have some parts still. I am hoping that the old one can be put back on. Not sure of the odds of that.

Post by **MrAl** » 10 Jan 2023, 13:24

volvolugnut wrote: ↑10 Jan 2023, 06:16 The hot air pipe to the air intake has history back to the early 240 Volvos. They helped engine warm up BUT if the thermostat that regulated the air flow failed, over heated air to the intake reduced fuel economy. Most of the hot air tubes were removed over time.
Volvolugnut

Oh that's interesting. I wish mine didnt have one but it does so i have to pull it out or something.
What are the chances this thing could break while removing, and i assume you just pull it out?

Post by **MrAl** » 10 Jan 2023, 13:26

scot850 wrote: ↑10 Jan 2023, 09:54 When they work, they work great to the point where it would have been good to have a similar arrangement for the turbos for cold climates. Helps the engine heat up much quicker and therefore the cabin as well. The thermostat is the only downside unfortunately, and unlike the 240 is not replaceable. I think I read a thread somewhere on someone who modified a P80 NA flap to use a 240 one.

Neil.

Hi,

What thermostat? There is one inside the pipe?