Engine Block Plugs

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911/Q45
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Joined: Tue Jul 23, 2002 12:10 pm
Car: Autos, Fitness

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Anyone got any tricks for removing the driver's side block plug to drain the antifreeze? It takes forever and I peel a lot of skin doing it. Passenger side is pretty easy, but I can't find the right angle on the driver's side.


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DAEDALUS
Posts: 6230
Joined: Mon Jul 22, 2002 8:50 pm
Car: 1990 Q45

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That one's been a mystery, and if you got 1 out you're doing better than most of us here. They get really frozen over time; maybe with your low mileage you have it a bit easier. There's a story floating around about how trying to remove a frozen plug can sometimes crack the block. I think most of us leave them alone and flush out our cooling systems with a garden hose followed by distilled water. If anyone has some real tips to help out, they'll be appreciated.

landtodd
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Joined: Thu Jul 25, 2002 7:05 am

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* Block drain plugs have to be removed hot. *

I took the thermostat out, opened the heater core, and backflushed for 20 minutes. Not the official way to do it, but I'm truly averse to scalding, and I have only so much skin on my knuckles.

I didn't use distilled water for the fill, for two reasons. 1) Without removing the drain plugs, you can't remove the flush water. 2) I'm still suspicious that mineral "hungry" water may cause unexpected errosion, but that opinion is based on limited GM experience, not Infiniti experience.

Havoline Orange 25% mix for all-alluminum engines.

Q45tech
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Joined: Tue Apr 30, 2002 3:19 am
Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl

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The Q has two cathodic anodes designed to corrode first!The thermostat cover housing and the tie metal pipe between the upper drivers side and lower radiator hose which is bolted to the block. If these are replaced every 6-7 years no corrosion is possible if the AF is maintained above neutral [slightly akaline].

Notice that the radiator is isolated [electrically] from the frame by the hoses and even the thermoswitch is in the plastic end tank.

Distilled water is necessary to absorb the years of abuse and corrosion build up in the block and head water passages.http://www.ctc-consultants.com/aluminum ... age32.html

The factory fill in Japan was distilled water [deionized]!!!!!!!!!!!!

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PalmerWMD
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Joined: Mon Apr 29, 2002 3:14 pm
Car: 2004 350Z

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landtodd wrote:* Block drain plugs have to be removed hot. *



I didn't use distilled water for the fill, for two reasons. 1) Without removing the drain plugs, you can't remove the flush water. 2) I'm still suspicious that mineral "hungry" water may cause unexpected errosion, but that opinion is based on limited GM experience, not Infiniti experience.

Havoline Orange 25% mix for all-alluminum engines.
You want "mineral hungry" water.The lower the ionic strength of a solvent, the more eagerly it will suspend any ions that may have snuck in and so the better it will be able to prevent scale from forming (or with luck even putting some existing scale back into solution).

High ionic strength water (such as almost all tap waters) have already neared their dissolution capacity, so in a way, they "push" solutes out of solution to precipitate (into scale).

Fred...:)

landtodd
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Joined: Thu Jul 25, 2002 7:05 am

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Hey, what do I know -- I JUST got done "driving mom's car," and now I'm trying to get these darned "hubcaps" off.

I refer to errosion in aluminum blocks, a fairly well-known phenomenon in early GM aluminum motors (4.1 to 4.9). Dennis posted a URL to a very interesting article on electrolysis a few months ago.

Dennis and Fred swear so often by distilled that I might go back on my current complacency and pull the drain plugs after all. It's time for a fresh fill anyway, since I'm replacing the under-plenum hoses (leaks) in the next couple of weeks.

I would love to be able to tell you I'm looking forward to it . . .

Q45tech
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Joined: Tue Apr 30, 2002 3:19 am
Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl

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We don't swear by it . It is a mandantory factory fill. The dealers are the ones who cheat, they don't want to spend the money [79 cents a gallon] and the techs won't buy their own so you get tap water to dilute the AF. The bulk also use tap water for batteries.

Why should they spend $1.00 it might mean you don't need a new radiator two years sooner. That doesn't make sense if you depend on non warranty repairs to keep the service department doors open.

Even T-3 uses tap water unless the customer brings it!

maxnix
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Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

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Hell, at less than $3.00 for a 5 Gallon bottle, just flush it three or four times. Much less stress on knuckles and freeze plugs too.


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