95 Voyager blowing bubbles

95 Voyager is blowing bubbles through the cooling system, suspect head gasket. Runs good but temp guage irratic. 4 cyl engine with AC & PS
Also rear wiper never worked but I hit the button anyway and the airbag light came on and stayed on.

I would say your suspicions are probably correct about the head gasket .

Air bubbles coming up in your overflow tank are indicative of a combustion gas leak into the cooling system. Search the Dodge/Not specified forum for my experiences with this in my Dodge Shadow. An air bubble from leaking gases that forms behind the thermostat will make the temp gauge go to full hot within the first few miles from start up before it opens for the first time.

The cause is either a bad head gasket, cracked head (valve seats), or cracked block (cylinder wall). Buy a "Universal Block Tester" and follow the directions to narrow it down. Make sure you know where the leak is coming from before you started dumping money.

I'm a little confused. I checked out the tester and it only tells you if there are combustion gasses in the coolant. This I can already see and smell in the overflow tank. It is a steady even stream of bubbles. How does this tell you if the head is cracked or the block or the gasket?

Well, I must admit that it is not that precise. But in the instructions for the block tester, it tells you how to narrow down which cylinder is giving you problems. It directs you to run the test with each of the cylinders disconnected, either by pulling the spark plug wire off or the fuel injector lead for multiport injection. If your problem is restricted to only one cylinder, you will get a negative result with the problem cylinder disconnected.

Now then, if your problem is a cracked cylinder bore, your leakage will be from one cylinder only and you will get a negative result with that cylinder disconnected. The same is true if you have a cracked valve seat in only one cylinder.

In the case of my 2.5L Turbo, I got possitive results all the time. My problem was with more than one cylinder, which at first I interpreted as a bad head gasket. When I removed the valve cover, I found that my #3 exhaust cam lobe had lost its harden surface and was scored up. When I took the head into the machine shop for rework, they discovered that all four exhaust valve seats in the head were cracked and replaced them all. They also installed a new cam, followers, lifters and new exhaust valve guides.

Now it won't hurt to run a compression test on the engine to see if cylinder pressures are equal all the way across or you got one or more low cylinders and whether or not any low cylinders are adjacent to each other. With mine, the pressures tapered down across the engine, with #1 being the highest and #4 being the lowest and 10% variation between high and low.

Unfortunately, you won't know for sure if the block is cracked until you put a a good head and head gasket back on the engine. My reworked head is now sitting on top of the block, waiting for me to bolt it down and put the rest back together.

Now, you did tell us it was a four cylinder in your van. Is it 2.2 or 2.5 and is it a Turbo? Also, how many miles?

No turbo, don't know if its a 2.2 or a 2.5. Over 100K miles. Spent the afternoon stripping the engine. Plugs looked OK if a little sooty. Number one was more brown in color than the others, but not washed out. There was no oil in the water or water in the oil so far. I'm working outside in a field with no power so cutting the exhaust bolts was a challenge. Replacing all the rotten and brittle vacume hoses that just snapped off when I moved them should be a lot of fun:) Never been inside an overhead cam before. When the sun comes up tomorrow and it warms up a tad I should have the PS, AC bracket, alternater and motor mount off so I can change the timing belt while I have it apart. Belt looked OK but I don't know its history, only had it a couple of years. Can a machine shop check the head if the manifolds are still on it? Or do I have to break some bolts first?

First of all, you will need to remove the motor mount to remove the timing belt.

You do not have to remove the AC compressor, alternator or power steering pump to do this job. I loosed the AC compressor from the mounting bracket and removed the bracket bolts to the head only. I removed the alternator and power steering belts but let these units remain there since their removal was not necessary.

When I removed the head on my engine, I removed the head, intake manifold, exhaust manifold and turbo as one assembled unit. Much easier to take off this way, but it takes two people to lift it. Once you get this unit out of the car, you can disassemble the manifolds from the head with lots of clearance to spare. Just be sure to put it all back together before you put it back in the car. Quite frankly, I don't think the manifolds or the turbo can be removed from the engine compartment of the Shadow without removing all together with the head.

You should remove the manifolds before taking the head to a machine shop. Don't remove anything else. Whatever they need to disassemble to service the head, they will put back on before giving back to you.

Good luck with your project and let us know how it progresses.

I opted to replace the head gasket and timing belt. Tranny went in my parts gopher lat night so its working in the rain today and beg a ride this afternoon for last parts run to get vacume hoses. Hope to fire it up before sundown.

Changed the timing belt and Head Gasket then all the vacume lines. Runs great now. Fuel lines into trottle body pissed gas when I first started it, but I shoved them in further and it stopped. There was no way I could get the c-clip back on the throttle, kept dropping it. I finally gave up and used the throttle return spring to hold it in place.