Cooling system issues

[swimmingly]

I ended up getting my car towed to a local radiator place in Santa Monica after my incident a couple days ago. They found the problem to be one of the hoses going to the heater core had burst from old age, according to them.

So, pass a couple of days, I drove home (all the way in Rowland Heights, the other side of LA county), park it on the driveway (the tank was between the min and max marks at this point), then the next morning I'm curious so I check my coolant level to find it essentially empty (that's right, there's drops in the reservoir tank!). I'm about to raise the car and try to figure out where it all went but I have a couple questions:

1. Can I take a "garden hose" (from the good ol' Hanes manual) and flush the system with normal water to help diagnose the problem and clean the system? Will this do any damage?

2. Could it simply be a clamp that they forgot to tighten or is there something that people often forget to do when working on the heater core that could cause some type of leak? Unfortunately, I wasn't around to see all my coolant go bye bye, so now I'm up to guessing and soon will be diagnosing.

Thanks in advance,
Matt

[KellyC]

If the hose has split due to age, its likely spit along the length of the hose. Is it a straight piece of hose, or a molded curved piece? If its straight just get some generic heater hose from pep boys and replace, if curved, you can order a hose set and do all of them at once or jury rig a straight piece and curve it...

I would HIGHLY recommend replacing all the hoses if you are keeping the car. If one hose is bad, there are likely many others that are ticking time bombs ready to go off.

Flushing the coolant system with tap water is fine, I wouldn't run the car extensively using tap water though. The easiest way to diagnose a leak is to borrow a pressure testers and pressurize the system, or you can have the car running. Replace the water with distilled and coolant... or the pre-mixed stuff.

[bearone2]

i'm not clear if they replaced the hose but it sounds like the radiator shop probably didn't bleed the system after adding water/coolant.

[swimmingly]

Holy crap! I was checking around underneath my car and I came to a very very astonishing discovery. One of my coolant hoses completely disconnected. I'm not exactly sure which one it is, but it's in the following pictures:



And here's the hose that came off of it:


Which hose is that? Is it expensive?

Also, I went somewhat picture crazy while down there, here's some pics for everyone to use of the underside of my car. Also, there's a diagram from Hanes and I tried my best to label where the pictures were from:
http://www-scf.usc.edu/~matthekc/pictures/under951/

One more, question not related to the cooling system. On images 11, 12, and 15, you can see some hose that looks like it's part of the PS system. It looks like it's leaking at the ends...are there suppose to clamps on the ends of that thing?

Thanks,
Matt

[dangerous]

that looks like the air vent for the alternator.....

[swimmingly]

Nuts, I just can't see in there so I wasn't sure. My leak must be somewhere else then, I suppose. Can having not vent the system properly somehow cause ALL the coolant in the reservoir to either be forced out of the system or taken into some pocket in the system?

[pokey]

If the system isn't burped properly, you can have an enormous air bubble in the system (your entire heater core was probably full of air). When the car gets up to operating temp, and the thermistat opens, all the coolant can seemingly disappear. Try topping the system up with coolant, and bleeding it properly.

[dangerous]

What he said!!!!
I've made that mistake before

[swimmingly]

Yes! Almost done making my cooling system closed. I got so fed up with calling Kragen, Autozone, etc and getting the "no, we don't rent cooling system pressure testers" that I ended up rigging up my own out of an old radiator cap and a bicycle tire (details on that later if anyone is interested). I put it on and started pumping (no greater than 10 psi), and voila, the system holds pressure decently, but I could hear the sound of escaping air.

I ended up breaking off the head of the bleed plug screw so I need to buy another one of those, but I tightened two clamps from where I heard a sound coming from and I think the only sound now is that that's coming from the bleed plug on the radiator (the tail was still screwed in, I must've tightened a little too much). Anyways, I'm off to get a new bleed plug screw tomorrow, then I'll put it at 10 psi, leave it at that for the night and come back in the morning to make sure it still held the pressure steady.

Any last tips on pressure checking and what not? I'm frankly a little hesitant to buy ALL of the cooling hoses because I have no clue where some of them are, but when I pressure it and leave it over night I hope that'll be the true test as to whether I need to change or tighten something.

[IceShark]

You now have mentioned snapping a bolt in the radiator. Not sure if you mispoke but that does raise another issue.

The end tanks are made out of plastic which ages and becomes brittle. It is very easy to crack those if you are not careful or have them just crack on their own.

You can get new end tanks and replace but it is almost as cheap to just buy a new, clean radiator.

[swimmingly]

It was the bleed plug screw, which seems to be made out of some really cheap plastic. It didn't take much to over tighten the thing and snap it. Anyways, I'm pretty sure that that's the only thing that broke.

[IceShark]

That is a drain plug rather than bleed screw. In any event it breaks if you look at it crossways so you always want to pull off the hose at the bottom of the rad rather than risk touching that plastic screw.

[swimmingly]

Oh, right. I meant drain plug. I don't know why I referred to it as the bleed screw here. Does anyone know the part number for a '86 951 radiator drain plug? On clarks-garage he says it's 944 106 353 00 since mine is an 86, but every dealer I called keeps referring me to 944 106 353 01. Anyone able to run a quick check for me on the PET? Thanks.

[rb101]

for the N/A the PET shows 944 106 353 00 for -86 and 944 106 353 01 for 87-

the M44.50/51 ,52 (951) should use the 944 106 353 01

[swimmingly]

Does that mean that ALL ('86 included) 951's should use the 944 106 353 01 drain plug?

[swimmingly]

Pressure tester made...
http://www-scf.usc.edu/~matthekc/pictures/pressuretester/

[rb101]

per the PET the -86 should use the 00 except the 86 951, everything from 87- use the 01 including the 86 951.

[SoCal Driver]

The drain plug on the radiators uses an O-ring to seal not the tightness of the plug.




The bleed bolt on top of the engine does use a brass washer as a seal.

Don't replace the radiator drain plug with a bolt. It will ruin the radiator.

[swimmingly]

This is mine...



Is that "metal" o-ring suppose to be on there? Reuseable?

[SoCal Driver]

That's a locking washer. Digs into the plastic of the radiator and the head of the plug. Yes the locking washer is supposed to be there. However I've found more without the washer than with.