2008 Dodge Grand Caravan, Coolant Leak Repair
Mark: Hi, it's Mark Bossert, producer of the Pawlik Automotive podcast and video series. We're here with Mr. Bernie Pawlik, Pawlik Automotive in Vancouver, Vancouver's best auto service experience. We're talking about a 2008 Dodge Grand Caravan this morning, that had a coolant leak. What was going on with this vehicle, Bernie? Good morning.
Bernie: Hey, good morning. This Dodge Caravan actually had a very large coolant leak coming from the back of the engine. Well, in between the engine and the transmission. Pour some coolant in, and it would be dripping out almost as fast as you could pour it in. Not quite, but, almost as fast as. So, yeah, there was a very major leak coming from this engine.
Mark: So after you dried your shoes off, what was causing such a large leak?
Bernie: What we found, what I suspected, and it actually involves removing the engine from the vehicle to verify it, was that there was probably a frost plug that had failed. It didn't take long ... soon as I removed the radiator cap, note right away there was a lot of rust on the radiator cap, and sitting in the top of the radiator. The owner of the vehicle had told me that they'd recently replaced the radiator, and so something that ... it wasn't even an old radiator, had rust in the coolant. To me, suspicious immediately of ... it's probably a rusted out frost plug.
Mark: What is a frost plug?
Bernie: What a frost plug is, it's also known as an expansion plug. They put them in the engine block, the purpose, one of the purposes, supposedly, is to prevent ... if you had water in the cooling system, so this goes way back to when before antifreeze was invented, or used. If you had water in the cooling system, of course, when it gets cold out, water freezes and it expands, and as it expands, of course it'll crack the metal of the engine block. If you put these plugs in, these frost plugs or expansion plugs, these plugs are supposed to be pushed out by the expanding water, and prevent the block from cracking. In reality, that usually doesn't work. I've had many vehicles in the past where people have had water in the cooling system, it freezes and cracks the engine block. They don't actually work like they're supposed to, but they also do, apparently, hold the casting ... when they cast an engine block they actually hold some of the molds in place as well, so that's another reason, apparently, for having them, although I've never actually been in a foundry and seen a block cast, but that's another purpose for it. Nonetheless, they need to be intact. They're made of ... they're generally a metal plug made of a thin, maybe 16th inch think, millimetre thick piece of metal that's hammered, it's hammered and friction fit into the engine block. They are susceptible to rusting out.
Mark: Why had this frost plug failed?
Bernie: Bad maintenance. Clear and simple. Bad maintenance. And by the way, this part, a frost plug is worth about a dollar, just to put things in perspective. The labor involved in replacing it is huge. Let's just go into some pictures right now. Basically bad maintenance is what caused it. The owner had probably, it's a 10 year-old van, probably should have the cooling system flushed at least once, maybe twice in this age of vehicle, and I would suspect never had it done. Maybe there's a coolant leak at some point, they let it run with some water in it for a while, and it's a cast iron engine block, so it will rust up. We're getting some pictures.
So there's the 2008 iconic Dodge Caravan, or popular as you would say. There's our first sign, before I even did any repairs on the vehicle, you can see the rust in the cooling system. That's a sign, right away, that there's a fair amount of rust throughout the cooling ... it never just stays in one spot, once it develops it tends to circulate around. There is a first telltale sign.
What's involved in this repair, is actually removing the engine and transmission from the vehicle, because it was leaking ... this is the bell housing area where the transmission bolts to the engine, and this is the rear frost plug. There's two of them, one here, one there. This is a cam shaft plug. This actually seals off an oil passageway. But there, where red arrow points, is a little hole that basically developed from the frost plug leaking out the coolant. When we look a little further, this is what the frost plugs removed ... and this is the kind of guck that was inside the back of the engine, the rust and corrosion. See, this is the back of the cylinder walls, these two areas, and this is just rust that had ... I stuck my fingers in here and dug a bit of it out, but that's basically the mess that was inside there.
In doing the service and repair I have a special flushing tool, and flushed all of it out. Still, once you develop this kind of rust, it's impossible to get rid of it all, but I probably removed about 95% of it in the process of doing this work. Just to look at things in perspective, after flushing out some of the heater hoses, this is what the coolant looked like. That's not yellow antifreeze, there are some antifreezes ... there are some antifreezes that have this colour, but this is definitely rusty water. So there's our picture show.
Mark: Basically, just from not flushing the coolant system, that would cause this much rust and damage in the interior of the engine?
Bernie: Yeah, as I said, my suspicion is that it may be that they ... well, first of all, it definitely didn't get flushed and serviced as much as it should've; and there was probably a time where it may have been low in coolant and the people had just put water in it for whatever temporary reasons. Maybe the temporary reasons were six months or a year, but between the two of those things, that's how the rust developed.
I actually purchased this vehicle from the owner. They didn't want to spend the money repairing it. So, essentially, they've taken a very good Dodge Caravan, with pretty low mileage, 150,000 km, and basically that vehicle is, to them, just junk. It's a shame, because one or two coolant flushes and some good maintenance, would be $200, $300. Not a lot of money. Yet, now they're out buying another vehicle. It really does pay to do your maintenance, especially ... if they'd paid for this repair, could be $3000 to $4000. Still worthwhile with the age of the van. It was otherwise in pretty good shape. Again, $300 or $3000, you know. As the Fram guy used to say, "You can pay me now, or pay me later." It's a classic example.
Mark: How often, other than too often, how often do you see these expensive repairs from lack of maintenance?
Bernie: From time to time we get vehicles in, and most of the times it's from people who haven't changed their oil enough, and the engine's just ... something's just blown up inside the engine. In all fairness, sometimes things blow up even for people who maintain their car well, but it's more often the lack of maintenance that causes these problems, or things that sludge up inside the engine, timing chain problems, rattles, cam gears. It's so important to change your oil and fluids regularly on modern cars. You don't need to do them as often as you did in the old days, I'm thinking 20, 30, 40 years ago, but with modern cars it's even more critical to do them when they're due or even sooner, just to ... it saves you a lot of money.
Mark: And Dodge Caravans have had a mixed, let's be kind, a mixed reliability record. Some years are pretty problematic with transmissions, and engines, depends on the motor. How is this generation of vans?
Bernie: These are pretty good. We don't see a ton of problems with them. It's been interesting ... with this engine I not only replaced the frost plugs, but I took the engine ... it had a couple of oil leaks, and I figured while the engine's out I may as well just re-gasket the whole engine, including the head gaskets, because you never know how hot this person got the engine, and I don't want to sell it to someone and find the head gasket's blown a month, or even a year.
Bernie: It's actually an incredibly simple engine, so there's not really a lot to go wrong with it. For reliability, the transmissions are definitely better than they used to be. Overall, they're actually a lot better than they used to be.
Mark: So there you go. If you're looking for maintenance and/or repairs on your Dodge Caravan, the guys to see in Vancouver are Pawlik Automotive. You can reach them at 604-327-7112 to book your appointment. You have to book ahead, they're busy, or check out their website pawlikautomotive.com. Hundreds of videos and articles on there about all makes and models. Of course, on our YouTube Channel Pawlik Auto Repair, same idea, hundreds of videos on all makes and models and types of repairs. Of course, thank you so much for listening to the podcast. We appreciate it. Thank you, Bernie.
Bernie: Thanks Mark, and thank you for watching and listening.