Tech Spam thread - because 1/4" BSP gets 5 hand spans to the jiggawatt

[RUNAMUCK]

Itll smell horrible the first time you heat cycle it too. 

[HighLUX]

Yeah I was expecting that/want to get it hot to really bake the paint on

[Snorkpipe]

On 26/02/2023 at 20:30, ajg193 said:

Are all die grinders crazy air hungry?

 

I got a Ryobi one and it is rated for something like 4 cfm at 90psi. My compressor, tested at 9.3cfm at 90psi, can't keep up with the bastard at all

Sorry, very slow reply.
How many horsepower do you need? How much do you want to spend?
4cfm 1hp https://shop.snapon.com/product/Heavy-Duty-Die-Grinders/1-HP-Heavy-Duty-Die-Grinder-(Red)/PTGR400

3cfm 0.5hp https://shop.snapon.com/product/Die-Grinders/1-2-HP-Die-Grinder-(Black%2FRed)/PTGR200

1.7cfm 0.3hp https://shop.snapon.com/product/Die-Grinders/1-3-HP-Mini-Die-Grinder/PTGR100

cheap 4cfm 0.3hp https://shop.snapon.com/product/Die-Grinders-(Blue-Point)/Standard-Air-Die-Grinder-(Blue-Point)/AT105

[Beaver]

Brakes. Pedal went too the floor but then kind of came back to life but feels very suspect. With car off, pedal will go stiff after a couple of pumps and stay stiff. If you keep pressure on the pedal and start car, pedal drops a but then keeps dropping slowly. It's a diesel and has vacuum pump on the alternator. Is making vacuum (30+ inch hg which is when my gauge bottoms out). No signs of fluid loss (internal or external). Car has been sitting with minimal use for last couple of years.

Any ideas before i start stripping the master cylinder and booster?

[RUNAMUCK]

I'd start with the master cylinder.

[h4nd]

Stand by charging (float) for e.g. house battery, with a top up setting for occasional Boost / equalise to help prevent sulphation.

This is a cheap crude approximation that's likely better than most single Voltage only chargers.

There's actually quite a lot of detail in charging batteries, including

• Different V, A for different types
• the correct voltage changes with temperature.
• Boost equalise time can depend on how discharged it was before charging
• etc

YMMV

The placement of the ammeter is an illustration which measures battery current only, so if the battery is charged, most of the current goes straight to the load (meter reads low current).

[mjrstar]

1 hour ago, Beaver said:

Brakes. Pedal went too the floor but then kind of came back to life but feels very suspect. With car off, pedal will go stiff after a couple of pumps and stay stiff. If you keep pressure on the pedal and start car, pedal drops a but then keeps dropping slowly. It's a diesel and has vacuum pump on the alternator. Is making vacuum (30+ inch hg which is when my gauge bottoms out). No signs of fluid loss (internal or external). Car has been sitting with minimal use for last couple of years.

Any ideas before i start stripping the master cylinder and booster?

Had very similar symptoms which was a sticky rear piston in one of the calipers, but agree with @RUNAMUCK start at the master cylinder..

[cletus]

Sometimes a dickered master cyl will have a sinking pedal if you gently rest your foot on the pedal but feel ok if you stomp on the pedal harder, this is because the extra pressure helps jam the worn seals against the piston bore better 

[sentra]

Can anyone explain a mystery why on a big old diesel motor if I pull the dipstick out after running it’s dry, but If immediately dip it again it’s full - like magic

its like there’s something hydrophobic (oilphobic???) on the stick after running

same deal if I shut it down and leave it until the next day, first check it’s dry, second and any subsequent checks it’s full

 

 

 

[Nominal]

Aliens

[sentra]

I made a video of it 

 

[johnnyfive]

The dipstick tube is airtight when stick inserted, stick doesn't go beyond tube, remove tube, oil assumes correct level in tube? Can't explain phenomenon that makes that happen initially, but something fucky with heat cycles and air expansion etc. Don't know if I've conveyed this properly

[Alfashark]

What's the overall condition of the engine? I've seen a Hyundai Lantra? where the dipstick did a similar thing but required multiple dips before anything would show. 

Sump off revealed a thick layer of hardened sludge within, and a long cone shaped pillar of sludge surrounding the dipstick at a tight enough tolerance that with the dipstick in place, it was oil-tight. Each removal of the stick allowed a little more oil up into the pillar until you'd get a reading.

[Beaver]

3 minutes ago, johnnyfive said:

The dipstick tube is airtight when stick inserted, stick doesn't go beyond tube, remove tube, oil assumes correct level in tube? Can't explain phenomenon that makes that happen initially, but something fucky with heat cycles and air expansion etc. Don't know if I've conveyed this properly

I agree with this man

[sentra]

The motors from early 90’s but only done a couple of hundred hours/religiously maintained as part of rescue fleet - nothing suggests crud but I will poke further to check 

 

What j5 said sounds sensible, I will just crack the stick a bit to break the vacuum and check next time - surprised this didn’t come in up when googling 

[h4nd]

[crash]

On 26/03/2023 at 21:47, h4nd said:

Can you provide a link to meter(s) please

[fletch]

On 26/03/2023 at 21:26, johnnyfive said:

The dipstick tube is airtight when stick inserted, stick doesn't go beyond tube, remove tube, oil assumes correct level in tube? Can't explain phenomenon that makes that happen initially, but something fucky with heat cycles and air expansion etc. Don't know if I've conveyed this properly

When it's running, the oil level drops as its all up in the head and block walls etc. Then it can run out of the tube and be all ghost oil level etc

[h4nd]

These are 10A, there's others.

https://www.aliexpress.com/item/1005002338207839.html

 

[Nominal]

On 21/02/2023 at 08:25, Nominal said:

Picked this up yesterday, probably won't have much generator protection.

No idea if it goes though.

 

@fletch Have this running now and it seems to start and run the pump OK, albeit with a bit of smoke and racket. Running a couple of extension cords mostly because I didn't want to drag the gen closer.

Probably should put the cover back on the electrics.