Question: My family has just been enlarged by three boys under the age of 5 (Grandma got custody). My question is, is it possible to enlarge the seating capacity of my '93 Plymouth Voyager from a five-passenger van to a seven-passenger van? We don't have a lot of money right now, so I'm thinking of going to the junkyard and buying the smaller central seat and all of the seat belts. Will that work? -- ConnieTom: Sure it will. All of the Voyagers are built to handle seating for seven. If you don't order the extra seat, they simply don't install it.
Ray: Or, if they're eager to move a car they already have on the lot, they may even just remove it.
Tom: So you can go to a junkyard and buy the smaller middle bench if that's the one you're missing. And -- at least on the earlier Caravans and Voyagers -- the seat belts used to come as part of the seat assembly itself. So you didn't have to buy anything else.
Ray: I'm not sure if that's true for the '93s -- especially with shoulder harnesses -- so you'll have to ask at the junkyard. Obviously, you'll need to make sure that every passenger has both a lap belt and a properly secured shoulder belt. And if worst comes to worst, you may have to get some of that equipment installed at a dealer.
Tom: But the answer is "absolutely," Connie. And while you're at the junkyard, you may even want to pick up some of that fake wood paneling that I'm sure you regretted not ordering back in 1993. And good luck with the kids -- you're a saint to take them in!
Question: I have an exhaust question for you. How hot can a catalytic converter get before there is damage? The reason I'm asking is because a local muffler shop demonstrated (with some sort of heat-detection device) that while my engine was at normal operating temperature, my catalytic converter was approximately 900 F. He said this is an indication that there is an obstruction of some kind in the converter. He recommended replacing it. Since the car is 13 years old, it seemed plausible, so I let him replace it. Was he right, or was I duped? -- Robert
Ray: Hmm. He may have had a boat payment due, Robert.
Tom: Exhaust temperatures are usually around 500 F. So 900 is high. The question is, WHY was your exhaust temperature 900 degrees? And I'm not sure the catalytic converter had anything to do with it.
Ray: Me either. In most cases, when a converter gets plugged, the performance of the car suffers, and that's how you notice the problem.
Tom: A hot converter could be caused by an over-rich mixture (too much gasoline, not enough air), the excess of which is getting burned in the converter. It could also be caused by retarded ignition timing, which could also cause the gas/air mixture to burn in the exhaust system rather than in the cylinders.
Ray: And if either of those problems is the case, your brand-new converter is probably running at 900 degrees now, too.
Tom: It's designed to withstand temperatures that high (and higher), but I'd still take the car to your regular mechanic, Robert, because you may have an engine problem. A muffler shop may have such a vested interested in focusing on the exhaust system that they may not be looking at the big picture. So ask your regular mechanic whether your converter is too hot, and if so, if he can find the cause.
The Magliozzi brothers' radio show "Car Talk" can be heard Saturdays at 10 a.m. and Sundays at noon on KUER FM 90.1, and on KCPW 88.3/105.1 FM Saturdays at 9 a.m. and Sunday at 10 a.m. If you have a question about cars, write to Click and Clack Talk Cars c/o King Features Syndicate, 235 E. 45th St., New York, NY 10017. You can e-mail them by visiting their Web site at http://cartalk.msn. com.