LS1 Radiator plug leak

**jad628** · 05-17-2006, 06:29 AM

Well I'm a couple of weeks into this 99 Z28 and I noticed I have a coolant leak. The heater core is leaking (will replace), but the biggest drip is from the drain cock on the radiator. I crawled under and I see about a three inch section of hose with the drain plug at the end and a standard band/screw adjust hose clamp securing it. Tightening the clamp made the drip a stream, so I did some adjustment to the plug and got it down to only a drip here and there. I bought a new plug, but I'm not sure about the short piece of hose. It doesn't look like a OEM type setup.

Being I'm new to the LS1 and I have GM manuals on the way - but not here yet - I have to ask:

Is this the "normal" setup, or did the previous owner maybe have a screwed up petcock and fabricate something to save having to replace a radiator? Not knowing this particular setup, I am curious. If there is some sort of "rebuild" kit for a common problem on the radiator drain, I'd obviously be interested. No cooling problems, and my first clue was the dash warning light for low coolant. Apparently a cup/pint low sets it off.

Any help/info is appreciated,

John

**sunsetorangess** · 05-17-2006, 06:56 AM

That sounds a lil odd. Your best bet is to drain the coolant so your not working against getting soaked then take "assembly apart". Who knows what the guy befor you did. Then try and make it right, picture would be great

**jad628** · 05-17-2006, 07:02 AM

Originally Posted by sunsetorangess

That sounds a lil odd. Your best bet is to drain the coolant so your not working against getting soaked then take "assembly apart". Who knows what the guy befor you did. Then try and make it right, picture would be great

Thanks,

I plan on doing just that. If I can't figure it out, I take a photo and post it.

My bet is that the petcock was damaged and this is a cheap "fix". It's either that or the hose extension was added to make draining the radiator a little less messy (but that's not what my money is on).

In either case, I'll git 'er done.

John

**sunsetorangess** · 05-17-2006, 07:07 AM

Lol atleast you got a good attitude and I agree with you on that "cheap fix" idear, im sure somewhere along the lines someone tried to drain it and fuged up the p-cock and got creative with some hose clamps and rad. hose. Just watch out for other stuff that might be "rigged"
J

**jad628** · 05-17-2006, 07:34 AM

Originally Posted by sunsetorangess

Lol atleast you got a good attitude and I agree with you on that "cheap fix" idear, im sure somewhere along the lines someone tried to drain it and fuged up the p-cock and got creative with some hose clamps and rad. hose. Just watch out for other stuff that might be "rigged"
J

What do you expect for an old 101st guy?

Checked out the car pretty good before I bought it, but it was close to ninety that week, then ONCE I bought it, we got down in the low forties. Turned on the heat and "POOF" I figured out the heater core leaks (my fault for not checking it).

Headliner was toast (I've replaced it myself $175 new)

Front speakers rattled (replaced with Infinity 2ohms myself $85 new)

No spare (bought one for $25)

One speaker grill messed up (bought for $5)

Missing Z28 rear badge (bought, waiting for it to come from EVIL? on this forum)

Headlights glazed over (bought halo eyes and waiting for them to arrive)

Rear brakes squealed (replaced myself, although they were not that bad).

Now just a pressure hose to the power steering, the pinion seal on the rear end, and the coolant thing.

Otherwise, it's just some clear coat stuff to fix and this car is 100%. Runs great.

John

**sunsetorangess** · 05-17-2006, 07:55 AM

goodstuff, saved alot of money by doing all the repairs yourself.
Trust me i know been fixin cars since i was old enough to turn a wrench, and will continue to do so until im physicaly un-able

**mrr23** · 05-18-2006, 03:30 PM

here's a pic of what the petcock should look like.

**jad628** · 05-22-2006, 03:48 AM

Originally Posted by mrr23

here's a pic of what the petcock should look like.

I appreciate the info. I must admit, I made this more complicated by my ignorance of the car. I bought it on April 30th, so I'm just learning the differences of the model.

Anyway, I solved my problem. The "petcock" I was seeing was on the driver's side. When I drained the system and removed the piece, I was greeted with the vision of an inlet/outlet connector for a 5/8" hose. Then I looked over to the passenger side and for the first time saw the REAL petcock. Duh!!!

The side I was dealing with looks like the connector for an oil cooler (if equipped). This car doesn't have one (may have had a different radiator installed due to a wreck), so the inlet/outlet had been "plugged" by someone previously and for the "plug" they used a four inch piece of 5/8" hose, two clamps, and another drain plug as the cap (held in place by one of the clamps). The hose had deteriorated and the clamp was cutting into it. I rigged up another one and used a little better setup with a cutoff cap, installed it, re-filled the system and - TADA - no leaks.

Next coolant change I'll actually get to use the appropriate petcock!!!

Thanks again for the help,

John

**Orcus79** · 05-22-2006, 05:57 PM

Do you have the auto or manual tranny?

**jad628** · 05-23-2006, 03:12 AM

Originally Posted by Orcus79

Do you have the auto or manual tranny?

Six-speed.

**jad628** · 05-23-2006, 11:54 AM

I noticed earlier that I said oil cooler. I beleive the radiator is for an AT and the outlet was for a tranny cooler. Sorry.

**Orcus79** · 05-23-2006, 08:59 PM

Thats why I was asking, no biggy. If that rad has been replaced with a bad radriator from an automatic it would be a good idea to go back to the proper one and give a thorough check of the rest of the car for any other "micky mouse farmer fixes" also check for any signs of a front end collission.

**jad628** · 05-24-2006, 08:42 AM

Originally Posted by Orcus79

Thats why I was asking, no biggy. If that rad has been replaced with a bad radriator from an automatic it would be a good idea to go back to the proper one and give a thorough check of the rest of the car for any other "micky mouse farmer fixes" also check for any signs of a front end collission.

The car did have front end damage (repaired in 2000 by the previous owner). I suspect from the condition of the short piece of hose that he obtained a NEW AT radiator and just plugged it off at the outlet. The rubber was deteriorated, but the radiator is in very good shape. Good call on the damage, but I did know about it since he was very upfront about the previous wreck. The "plug" wasn't discussed, but I don't blame him since it would be easy to forget.

It's working fine and no leaks since I worked on it. I believe I'm good to go.

John

**Orcus79** · 05-26-2006, 10:38 PM

Ok here is the thing what is pluged off is the cooler for the transmission and should be a sealed unit. If fluid is coming out of it could be left over trany fluid or there is a small leak in the cooler, could be why it is now in a manual car. If you stopped it I wouldn't worry about it, but look into getting a proper one in the near future.