Chevy & GMC Vans

I just got home and it is quite dark, but my wife pointed out there was a puddle under the van which you could see when we pulled in. After getting a flashlight, I had a look to see what it could be. While I couldn't tell by smell, and the puddle was large but not huge, I decided to check fluid levels. I started with antifreeze, and sure enough, looking in the rad it is so far down that it looks like the rad is empty. It is too dark to see where the leak is, I am hoping it is not the intake manifold as without help I don't think I could do that myself. Where should I look to come to a conclusion.

Run the engine and see if you can find the squirt, or drip, or whatever.

Trace along all the channels. First the two large diameter radiator hoses, then the smaller heater hoses, and don't forget the overflow reservoir.

Ant that something.These vans seem to know what time of the yr it is and start leaking coolant.<mine too >

Pull the air filter box off and top shroud.That way you can see the front of the engine.

Pull the doghouse to see the rear of the engine.

Get the van up on jack stands so you can look under it.

Clean is the real deal here.I used brake cleaner and was very careful not to get near any wiring harness or sensors.(cleaners like that are not good for them)I bought from HF a blow gun that extents the end out so I could blow off dirt in hard to get to places.

I bought a dye kit from Autozone that has the dye and a L.E.D. black light
flashlight.Added the dye to the rad and ran it to see where the leaks are.Now I know there a plenty of guys that would say it isn't necessary to buy that kit.I don't disagree with that.All I am saying is it sure does make it tons easier to see leaks in hard to see places.

You might want to post if you have rear heat in your van.I have replaced those hoses on mine once.

Good luck on your search and please let us know what you find.

1Gary wrote:Ant that something.These vans seem to know what time of the yr it is and start leaking coolant.<mine too >

Pull the air filter box off and top shroud.That way you can see the front of the engine.

Pull the doghouse to see the rear of the engine.

Get the van up on jack stands so you can look under it.

Clean is the real deal here.I used brake cleaner and was very careful not to get near any wiring harness or sensors.(cleaners like that are not good for them)I bought from HF a blow gun that extents the end out so I could blow off dirt in hard to get to places.

I bought a dye kit from Autozone that has the dye and a L.E.D. black light
flashlight.Added the dye to the rad and ran it to see where the leaks are.Now I know there a plenty of guys that would say it isn't necessary to buy that kit.I don't disagree with that.All I am saying is it sure does make it tons easier to see leaks in hard to see places.

You might want to post if you have rear heat in your van.I have replaced those hoses on mine once.

Good luck on your search and please let us know what you find.

I think I may have some dye for the rad left over from a kit I bought to diagnose an oil leak on my Sunrunner. I will have to look.

1Gary wrote:Ant that something.These vans seem to know what time of the yr it is and start leaking coolant.<mine too >

Pull the air filter box off and top shroud.That way you can see the front of the engine.

Pull the doghouse to see the rear of the engine.

Get the van up on jack stands so you can look under it.

Clean is the real deal here.I used brake cleaner and was very careful not to get near any wiring harness or sensors.(cleaners like that are not good for them)I bought from HF a blow gun that extents the end out so I could blow off dirt in hard to get to places.

I bought a dye kit from Autozone that has the dye and a L.E.D. black light
flashlight.Added the dye to the rad and ran it to see where the leaks are.Now I know there a plenty of guys that would say it isn't necessary to buy that kit.I don't disagree with that.All I am saying is it sure does make it tons easier to see leaks in hard to see places.

You might want to post if you have rear heat in your van.I have replaced those hoses on mine once.

Good luck on your search and please let us know what you find.

I did a little more snooping and the leak seems to be at the front from the area of what I believe is the water pump (lower rad hose runs into it). It looks dry above that, but the van is nose down on a slight incline so something could be leaking further back and running forward.

I believe I have a dye for the radiator left over from a kit I purchased to diagnose an oil leak on my Sunrunner. It came with one of each so it is just a matter of finding it. Thanks for the reminder that such a thing exists.

I just tried checking and it looks like the wetness starts on the water pump but not above it. I was going to pull the upper shroud off, but an unpleasant side-effect of one of the medications I am on since my stroke in January, is that my hand get cold really fast. Just the quick poking around and my hands were freezing cold so I couldn't feel anything anymore. Hopefully, since it is a bright sunny day, it will warm up enough that I can get a good look at things.

Some questions. Do I have to take the air cleaner box off the fan shroud to get the shroud out? If so, how do I get it unhooked from the shroud as while the one mount for the air box is broken, the other is not and I don't really want to break it. Second, looking at the shroud I see a few bolts along the top and some down at the bottom on the sides. How many are there and where are they located and what is the easiest way to get at all of them?

To remove the air filter box, just carefully wiggle and pull up at the same time. If you take out the air filter, you can see the 3 mounting points.

EDIT: Oops, I take that back. I overlooked that you have an earlier model.

The shroud has 7 bolts, 3 at the rad support and 2 on each side about at the middle. They are 10mm heads and the best way to remove them is with a ratchet and long extensions (for the side ones).

On the 94 there are three bolts to hold down the air filter box.If one bolt is just spinning all it means is the clip that fits threw the shroud with a nut for the bolt to go threw slipped off the shroud.Once you get the air filter box off you can take some vise grips and spray the clip with pen oil to reinstall them on the shroud.With mine I found I had new clips to use which grip the shourd better.

I took off the air filter box because I found I could get to the shroud bolts better on the driver's side bottom bolts.There are 6 bolts that hold the top shroud on.Two on each side on the bottom and a wobble extension helped a lot in that case and on the top there are one bolt on each side that bolt threw the rad cross member.You can find them easy because you will find rib reinforcements on each side of where the bolts go threw.The shroud you will find needs "some" convincing to get it out by "light" bending.Be careful that the shroud corners don't scrape across the rad while taking it out or putting it back in.

LiftedAWDAstro wrote:The shroud has 7 bolts, 3 at the rad support and 2 on each side about at the middle. They are 10mm heads and the best way to remove them is with a ratchet and long extensions (for the side ones).

Aaaaaaa-genII are different.Added one more bolt to rad support.The rad support bolts are smaller on the 94 too.

Btw-maybe someone could give the tech term for those spring clips I was trying to describe that the air filter box bolts go threw.They are the same type on the bottom of the shroud too.

I may just end up paying someone for this. I tried working on it, and it is too cold for my hands. Add to that the fact we need the van quickly, and my lack of time due to work, and suddenly it looks preferable to pay. If it is the intake manifold gasket, without someone to help, I don't feel confident to do it. Decisions, decisions.

Jim,that decision might be best for you.I suggest a lot depends on where you are at home trying to do the work.Bill/Billy do work under a carport,but I think just the fact of being under cover makes a huge difference and I would think Bill over the yrs has created a ideal work space.A garage over the driveway in my opinion does matter.As you say,time is a factor too.

That was sort of my thinking. Garage is full, not to mention the trailer is in the way. It is a busy week where we need both cars available especially later in the week, and I just got back from vacation so there is lots of catching up needed from when I was away. As much as I hate paying people to do work I could do myself, this is an instance where I likely could not do it myself due to time and, if it is the intake manifold gasket) experience enough to do it.