4.3L Engine Block Drain Plugs

FROM RADIATORS TO THERMOSTATS TO HEATER CORES, IT GOES HERE.

Moderator: LiftedAWDAstro

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

4.3L Engine Block Drain Plugs

Post by infinite.chris » Tue Jan 29, 2013 4:37 am

Just curious where these two are located on my '95 cargo?? There's only one picture I found and not much online I've been able to find. Half tempted to just pay a shop to do a flush and be done with it. But I feel anywhere I go, it'll be $100 and they'll find something else to "fix."

I've read that one is in front of the oil filter on DS, and the other located pretty much parallel by the starter, but I peaked under it the other day at those locations with no luck.

Or, would it be best to do a flush and just test my coolant and add coolant / water to ratio??
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

User avatar
timelessbeing
Site Admin
Site Admin
Posts: 2715
Joined: Fri Aug 08, 2008 7:55 pm
antispam: No
How many wheels are on an Astro van? (4): 4

Re: 4.3L Engine Block Drain Plugs

Post by timelessbeing » Tue Jan 29, 2013 8:03 am

what are you trying to do?

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

Re: 4.3L Engine Block Drain Plugs

Post by infinite.chris » Tue Jan 29, 2013 12:25 pm

timelessbeing wrote:what are you trying to do?
Just trying to drain the block and the rest of my coolant. Thought I did a decent job of it back in the fall but it seems like there's too much water in the system. Started overheating on my and there was plenty of liquid in the system, yet it was overheating / no heat was coming into the cabin.

The day before that it wasn't quite so cold and some heat had eventually reached the cabin, just not much until it got up to temp.
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

User avatar
doyoulikeithere
ASV Supporter
ASV Supporter
Posts: 2086
Joined: Wed Nov 18, 2009 4:27 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Misty Mountains of Cowichan BC.

Re: 4.3L Engine Block Drain Plugs

Post by doyoulikeithere » Tue Jan 29, 2013 6:15 pm

Its true, there are spots on either side of the block near the bottom where you described earlier.
Many times it will just be a plug, not a drain-cock, or, it could even have a knock sensor screwed into it. (mine did on drivers side)
Doubt you will ever see a drain cock there unless someone put it there themself, but its the best spot to put one.. Hint hint....
2016 Yamaha XSR900 - Silver.
2006 Kawasaki KLR 650 - Red.
1990 Astro - AWD
1987 Astro - With 5 Speed & 4wd.

User avatar
timelessbeing
Site Admin
Site Admin
Posts: 2715
Joined: Fri Aug 08, 2008 7:55 pm
antispam: No
How many wheels are on an Astro van? (4): 4

Re: 4.3L Engine Block Drain Plugs

Post by timelessbeing » Tue Jan 29, 2013 9:43 pm

The bad news is your logic is flawed. The good news is your job will be much easier.

Fact: Antifreeze is a poor cooling agent. In fact, water works twice as well. The reason why we add it, is as the name suggests: to prevent freezing (and also to inhibit corrosion and lubricate the water pump). Therefore, a weak solution will not cause your vehicle to overheat.

If you live in a warmer climate, and rarely dip into freezing temps, a 50/50 mixture is just fine and you can eyeball it. If it gets very cold where you are, the best protection will be achieved at 60% antifreeze, 40% water. Get yourself a coolant tester for a few bucks, and add antifreeze until the desired proportion is achieved.

If your system was overheating, you should have extra heat coming into your cabin, right? Not sure what your reasoning was there, but that sounds like an unrelated problem. Check your heater hoses and make sure you have some flow. You could have a blockage in the heater core, a valve problem, or failing water pump. Actually, since you say that you do get heat eventually, it sounds like your thermostat is stuck open. Or possibly installed backwards.

Unless you have very serious issues with your engine, you do no neet to open any freeze plugs or whatever to change out your coolant. Just circulate some fresh water to get the old stuff out, and add antifreeze as needed. I wrote a very easy procedure here: viewtopic.php?f=54&t=5986&p=64731#p64731. But since you already did a flush, I think you're barking up the wrong tree. Check your thermostat.

Good luck and let us know how it goes.

http://avenger-valkyrie.org/techinfo/antifreeze.htm

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

Re: 4.3L Engine Block Drain Plugs

Post by infinite.chris » Tue Jan 29, 2013 10:19 pm

I agree with all that except my thinking is its not that its the mixture in attributing to its lack of coolant. Its mainly the fact that I'm supposing the water I did have was enough that froze and blocked my coolant lines keeping everything from flowing smoothly.today and yesterday were the first days we've had north of freezing since two weeks back.
timelessbeing wrote:The bad news is your logic is flawed. The good news is your job will be much easier.

Fact: Antifreeze is a poor cooling agent. In fact, water works twice as well. The reason why we add it, is as the name suggests: to prevent freezing (and also to inhibit corrosion and lubricate the water pump). Therefore, a weak solution will not cause your vehicle to overheat.

If you live in a warmer climate, and rarely dip into freezing temps, a 50/50 mixture is just fine and you can eyeball it. If it gets very cold where you are, the best protection will be achieved at 60% antifreeze, 40% water. Get yourself a coolant tester for a few bucks, and add antifreeze until the desired proportion is achieved.

If your system was overheating, you should have extra heat coming into your cabin, right? Not sure what your reasoning was there, but that sounds like an unrelated problem. Check your heater hoses and make sure you have some flow. You could have a blockage in the heater core, a valve problem, or failing water pump. Actually, since you say that you do get heat eventually, it sounds like your thermostat is stuck open. Or possibly installed backwards.

Unless you have very serious issues with your engine, you do no neet to open any freeze plugs or whatever to change out your coolant. Just circulate some fresh water to get the old stuff out, and add antifreeze as needed. I wrote a very easy procedure here: viewtopic.php?f=54&t=5986&p=64731#p64731. But since you already did a flush, I think you're barking up the wrong tree. Check your thermostat.

Good luck and let us know how it goes.

http://avenger-valkyrie.org/techinfo/antifreeze.htm
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

User avatar
timelessbeing
Site Admin
Site Admin
Posts: 2715
Joined: Fri Aug 08, 2008 7:55 pm
antispam: No
How many wheels are on an Astro van? (4): 4

Re: 4.3L Engine Block Drain Plugs

Post by timelessbeing » Tue Jan 29, 2013 11:20 pm

:-k Hmm I hadn't considered that. Were not used to temps that cold around here ... I've never heard of an engine block freezing. You would had to have had less than about 20% antifreeze in there for it to freeze at 0deg F.

Wait until it's warm enough, and use the coolant tester as I said. If it's too weak, drain some out of the radiator. There should be a plug at the bottom where the the hose comes out. If it's stuck (like mine), just remove the hose. Then add coolant to the radiator and take it for a drive so it mixes throughout.

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

Re: 4.3L Engine Block Drain Plugs

Post by infinite.chris » Tue Jan 29, 2013 11:45 pm

Me either, and it usually doesn't stay this cold that long :-k it didn't even get down to the neg's, coldest was 5-7deg.

Just got back from adding the rest of my 50/50 and filled the rest of the mass with water. It ended up taking about a gallon and a half of fluid total. Thermo seems like it's okay, got up to 230 and kicked in, water pump sucked down the water / coolant I had added. After that it didn't get above 210 either idling or driving home. I'm SO glad it's been 50* for a couple days in a row, FINALLY.

Side comment, still related. The air coming out of any vents was about the same temp as outside with it idling, until I started driving. Once it was going down the road it was toasty! Friggin weird. Starting to think my heater core may be janked up too.
timelessbeing wrote::-k Hmm I hadn't considered that. Were not used to temps that cold around here ... I've never heard of an engine block freezing. You would had to have had less than about 20% antifreeze in there for it to freeze at 0deg F.

Wait until it's warm enough, and use the coolant tester as I said. If it's too weak, drain some out of the radiator. There should be a plug at the bottom where the the hose comes out. If it's stuck (like mine), just remove the hose. Then add coolant to the radiator and take it for a drive so it mixes throughout.
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

User avatar
timelessbeing
Site Admin
Site Admin
Posts: 2715
Joined: Fri Aug 08, 2008 7:55 pm
antispam: No
How many wheels are on an Astro van? (4): 4

Re: 4.3L Engine Block Drain Plugs

Post by timelessbeing » Wed Jan 30, 2013 12:32 am

On cold days, it takes at least 5 minutes of driving for my heater to get warm. Idling, it takes much longer since the engine is not under load.

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

Re: 4.3L Engine Block Drain Plugs

Post by infinite.chris » Wed Jan 30, 2013 12:37 am

Mine will usually be warm about halfway into work (22 miles total) this was weird, though. When it was sitting it was maybe 50* air coming out, and then when I was going down the road it jumped right up to a toasty ~70 deg, and then stayed that warm. *scratches head* GM, I wonder about you.
timelessbeing wrote:On cold days, it takes at least 5 minutes of driving for my heater to get warm. Idling, it takes much longer since the engine is not under load.
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

User avatar
timelessbeing
Site Admin
Site Admin
Posts: 2715
Joined: Fri Aug 08, 2008 7:55 pm
antispam: No
How many wheels are on an Astro van? (4): 4

Re: 4.3L Engine Block Drain Plugs

Post by timelessbeing » Wed Jan 30, 2013 3:24 am

That's not totally shocking. When you start driving, the water pump pumps about twice as fast.

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

Re: 4.3L Engine Block Drain Plugs

Post by infinite.chris » Wed Jan 30, 2013 3:43 am

Good to know! :)

I'm hoping it warms up this coming weekend so I can do another flush, I figure my coolant mixture is likely 80% water / 20% coolant. And I'd like to get it closer to 50/50 overall.

I'm thinking if the engine itself holds two gallons, if when I'm draining, I just add two gallons of 50/50 after flushing, it'll be close to that ratio, heck of a lot closer than it is now & just test it. If m tester says I'm good to betond below 10 degrees, button it up and life is good :)

Thanks!!
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

User avatar
timelessbeing
Site Admin
Site Admin
Posts: 2715
Joined: Fri Aug 08, 2008 7:55 pm
antispam: No
How many wheels are on an Astro van? (4): 4

Re: 4.3L Engine Block Drain Plugs

Post by timelessbeing » Wed Jan 30, 2013 7:14 am

The radiator holds two gallons. It's far easier to drain that.

User avatar
doyoulikeithere
ASV Supporter
ASV Supporter
Posts: 2086
Joined: Wed Nov 18, 2009 4:27 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Misty Mountains of Cowichan BC.

Re: 4.3L Engine Block Drain Plugs

Post by doyoulikeithere » Thu Jan 31, 2013 6:22 pm

Just FYI...I still hold true that there are threaded holes (not freeze plugs) on either side of the block, where you could thread in a drain cock at the very lowest point on the block, if you wanna drain it as originally posted. My 87's had Knock sensors screwed into that hole on drivers side and just a threaded plug on the passenger side, but my marine 4.3 has a draincock for coolant in that same hole in the block.
2016 Yamaha XSR900 - Silver.
2006 Kawasaki KLR 650 - Red.
1990 Astro - AWD
1987 Astro - With 5 Speed & 4wd.

infinite.chris
I get chills without my van.
Posts: 90
Joined: Sat Feb 11, 2012 6:46 am
antispam: No
How many wheels are on an Astro van? (4): 4
Location: Holland, Ohio

Re: 4.3L Engine Block Drain Plugs

Post by infinite.chris » Fri Feb 01, 2013 1:00 am

Noted! I'm thinking I'll pop those in when I do my steering in the spring. I'm felling van withdrawl, needs to get into the 30's-50's again. :[
doyoulikeithere wrote:Just FYI...I still hold true that there are threaded holes (not freeze plugs) on either side of the block, where you could thread in a drain cock at the very lowest point on the block, if you wanna drain it as originally posted. My 87's had Knock sensors screwed into that hole on drivers side and just a threaded plug on the passenger side, but my marine 4.3 has a draincock for coolant in that same hole in the block.
[SCRUFFY 95 RWD Astro Cargo :: 227k ]

------------------------------------------------

Post Reply