2011 Sentra - vacuum fill required?

[troymcclure]

2011 Sentra. FSM says to change the coolant with a vacuum fill. Anyone have any experience with doing a simple funnel bleed on this car or other similar Nissans? I don’t want to attempt it if it’s going to be impossible to bleed in the traditional manner. I don’t have a compressor or the workspace to get one so a vacuum bleeder is out of the question for now. Not too many experiences posted on the internet.

 

[slacktide_bitog]

Do you have a Lisle funnel?

 

[troymcclure]

Do you have a Lisle funnel?

EPauto brand but same design. Works great on my Honda but that FSM just says drain, fill, and run for a bit with the rad cap off.

 

[slacktide_bitog]

It seems like that's all you need

 

[troymcclure]

Thanks! Seems to have worked out fine for that guy. Hopefully his next video wasn’t a head gasket replacement .

 

[slacktide_bitog]

Thanks! Seems to have worked out fine for that guy. Hopefully his next video wasn’t a head gasket replacement .

Head gasket sealers have gotten really good

 

[SC Maintenance]

If its telling you to use a venturi based vacuum system - thats the Nissan default procedure.

On my VQ's - the issue is the rad cap is not the lowest point in the system - so its easy to get a air bubble.

The other issue is people do not realize the "overflow" bottle is actually a degas bottle and its part of the cooling system. Not sure if yours is - but does your bottle have the spring cap - and the rad has the solid (no spring) cap with a pressure rating of like 50PSI?

The way I do my VQ's - which possibly are totally different?? is drain, measure what came out refill completely, then fill the degas bottle with however much gets me back to what came out. So at that point its way overfull. Then I run it just till it hits close to operating temp - shut off and let it cool. Hopefully it sucks the degas bottle overfill back into the system.

Sometimes you can't get enough in the degas - you need some space - so it becomes a 2 step process. I have read others use the lisle funnel, or park on a hill and let it run, and all kinds of other voodoo.

Yes, Nissan's are a bit different.

 

[troymcclure]

If its telling you to use a venturi based vacuum system - thats the Nissan default procedure.

On my VQ's - the issue is the rad cap is not the lowest point in the system - so its easy to get a air bubble.

The other issue is people do not realize the "overflow" bottle is actually a degas bottle and its part of the cooling system. Not sure if yours is - but does your bottle have the spring cap - and the rad has the solid (no spring) cap with a pressure rating of like 50PSI?

The way I do my VQ's - which possibly are totally different?? is drain, measure what came out refill completely, then fill the degas bottle with however much gets me back to what came out. So at that point its way overfull. Then I run it just till it hits close to operating temp - shut off and let it cool. Hopefully it sucks the degas bottle overfill back into the system.

Sometimes you can't get enough in the degas - you need some space - so it becomes a 2 step process. I have read others use the lisle funnel, or park on a hill and let it run, and all kinds of other voodoo.

Yes, Nissan's are a bit different.

Interesting I had to look up what a degas bottle is since all of my cars have an overflow bottle with a single hose going from the radiator neck, vented and not pressurized. Cap is the highest point of the pressurized system although on the Nissan, the overflow tank is up at the firewall. Seemed no different than my Honda but wanted to hear why Nissan may have specified the Venturi system. It does seem way more convenient for a shop or dealer as it appears to avoid needing to idle the engine for 40 min which is a waste of gas and time.

 

[14Accent]

Nissan cooling systems are notoriously difficult to bleed, hence the vacuum fill recommendation. I remember fighting with many a Quest/Villager back in my early days of wrenching... we serviced a fleet of them that got used hard as transportation vehicles. A vacuum fill on those was a necessity.

A cheap vacuum refill kit is $50 on Amazon, I'd look into one of those.

 

[newoilguy1]

How much air compressor do the Venturi systems need? Been seeing a few pop up on my YouTube feed. Seems easier than any other procedure, but I only have 6 gal / 1.7 SCFM @ 90 psi

 

[Tempest1]

I shelled out for a Snap On Vac filler system last year and don't regret it. Very painful to the wallet, but makes changing fluid a breeze.

For my CX-5, a small Makita Mac700 works fine. You can close the valves to maintain vacuum if the compressor has to cycle.

Make sure to never let the feed tube into the air during the process.

 

[michaelluscher]

Nissan cooling systems are notoriously difficult to bleed, hence the vacuum fill recommendation. I remember fighting with many a Quest/Villager back in my early days of wrenching... we serviced a fleet of them that got used hard as transportation vehicles. A vacuum fill on those was a necessity.

A cheap vacuum refill kit is $50 on Amazon, I'd look into one of those.

I also remember the first time bleeding my Villager (and the same engined Pathfinder)
That Lisle funnel earned it's keep on the shelf many times over

A vacuum filler is a more efficient one step procedure, but if you don't have the budget or the air supply, the funnel should get you there
Just understand that you'll need to let the fans cycle ~3 times, and give it a minute or two of steady ~1500 rpms high idle

 

[14Accent]

I also remember the first time bleeding my Villager (and the same engined Pathfinder)
That Lisle funnel earned it's keep on the shelf many times over

A vacuum filler is a more efficient one step procedure, but if you don't have the budget or the air supply, the funnel should get you there
Just understand that you'll need to let the fans cycle ~3 times, and give it a minute or two of steady ~1500 rpms high idle

I did a few with the Lisle funnel... good times. Jack the front end WAY up because the cap was in such a bad position, let it get warm/spill everywhere as the coolant expanded before the 'stat opened... rinse (literally) and repeat. Sometimes it was just easier to fill the funnel to the brim and go home for the day, by morning gravity had done it's thing.

 

[nthach]

IME wirh Nissans, an AirLift is your best friend - especially on the VG engines. Nissans tend to have a mess of bypass hoses and hard lines that love to trap air.

If you don’t have one, IIRC there’s a bleed plug on some models near the throttle body or some high point on the engine. Open that up while filling the cooling system. Use a spill free funnel to create another high point to air to leave. Run the engine with the bleeder open. Close it when you see coolant spill steadily, no froth. Use the spill free funnel to monitor for air bubbles. Shut down the engine, close the rad cap, top off the reservoir and let the engine cool down.