1997 850 Sedan Base Some Quirks

[davolvo]

Really, the top of the dash? Huh, would of never crossed my mind. I thought I would have to take the glass/plastic front off and then the gauge thingy to get to the bulbs. Thanks.

[850 LPT]

This tutorial will get you the idea, it's for S/V 70 but it's essentially the same for 850.

https://www.matthewsvolvosite.com/forums ... 4&p=126022

[davolvo]

WOW, thank you so much! I really appreciate that.

[erikv11]

Uhmmm, where is it in this vehicle?

Here is a very good description and a link to some instructions that will help you remove it:
https://www.matthewsvolvosite.com/forums ... =1&t=36657

And here are some pics of the flame trap, it is the round plastic insert with all the little holes in it:

[davolvo]

Oh wow, so what exactly is it meant for? I know what "flame" and "trap" means of course but was it placed there to avoid engine fires or something? Thanks for showing me where it is, so if I remove it my blue glove may suck in a little maybe?

[erikv11]

Oh wow, so what exactly is it meant for? I know what "flame" and "trap" means of course but was it placed there to avoid engine fires or something? Thanks for showing me where it is, so if I remove it my blue glove may suck in a little maybe?

It was supposed to help prevent combustion from traveling through the PCV lines, apparently there was speculation that such combustion might occur. I guess traveling from the throttle body to the crankcase, I have read about it before but I don't remember the details. However Volvo eventually discontinued the flame trap without any other changes to the system. Do some searching you can find a lot about it but bottom line is, it serves no purpose and gets in the way.

Yep, if the flame trap is still in there and is clogged up, then removing it may improve the suction on the glove test.

[rspi]

However Volvo eventually discontinued the flame trap without any other changes to the system. Do some searching you can find a lot about it but bottom line is, it serves no purpose and gets in the way.

Are you saying that the '98 S70 NA has the same connection at the base of the throttle body but NO flame trap?

My 1987 Volvo had a flame trap. So, they used them for several years.

[rspi]

Here is a video for the dash pad removal. The tough part is getting the airbag side of the pad to free from the brace. It is kinda hard. I would suggest a 16 year old for this job.



This video will show you a little about the light bulbs.

[erikv11]

However Volvo eventually discontinued the flame trap without any other changes to the system. Do some searching you can find a lot about it but bottom line is, it serves no purpose and gets in the way.

Are you saying that the '98 S70 NA has the same connection at the base of the throttle body but NO flame trap?

My 1987 Volvo had a flame trap. So, they used them for several years.

Interesting that the older cars had them too.

Only one of the four 850 NAs I have worked on came with a flame trap, the others it was already removed. So I have not checked that many cars and in this case bottom line is really I only know what I read and hear on the forums. I did just read on that old Bay13 writeup (see links above) that it was in the 93-97 cars (850s) but not in the 98s; that was from Rich Kelly who is a master.

[Ben850]

However Volvo eventually discontinued the flame trap without any other changes to the system. Do some searching you can find a lot about it but bottom line is, it serves no purpose and gets in the way.

Are you saying that the '98 S70 NA has the same connection at the base of the throttle body but NO flame trap?

My 1987 Volvo had a flame trap. So, they used them for several years.

Interesting that the older cars had them too.

Only one of the four 850 NAs I have worked on came with a flame trap, the others it was already removed. So I have not checked that many cars and in this case bottom line is really I only know what I read and hear on the forums. I did just read on that old Bay13 writeup (see links above) that it was in the 93-97 cars (850s) but not in the 98s; that was from Rich Kelly who is a master.

When I had taken ownership of my '93 n/a Sedan (no Turbo in '93), someone had already taken out the flame trap, (breaking the elbow and siliconed) but also had utilized a 3/4" fuel line to bypass the oil separator line.

First 850 PCV.

IMG_1130.JPG (141.53 KiB) Viewed 787 times

Flametrap elbow.

IMG_1125.JPG (87.84 KiB) Viewed 787 times

Large fuel line above the injector cover.

IMG_1122.JPG (108.17 KiB) Viewed 787 times

I replaced the elbow with a new one from an FCP kit, discarded the "flame trap", cleaned out the block passages, and the '93 n/a is still running nicely after a year and a half.


While replacing the PCV system on my turbo wagon, I used 5/8" heater hose for the run to the intake, and 1/4" fuel line for the vacuum run to the PTC nipple.