Is it possible to remove the heat exchangers and examine the exhaust pipe running through them for leaks without pulling the whole engine? Winter is coming and I'd like to hook the heater tubes back up, but don't want any CO sneaking in since mey son loves riding in our "new" 66 bug.
Thanks!
Is it possible...
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fatalifeaten
- Senior Member
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- Joined: Sun Feb 03, 2008 12:05 am
- Location: The 480
yes, and no. You can get them off by unbolting the exhaust and then unbolting them from the heads without having to take the engine out, but I'm not certain you can take them apart to look at the actual exhaust pipes that run through the center of the heater boxes. I'll defer to someone with better knowledge here because I've never tried and usually toss or donate my heater boxes.
Getting them off with the engine installed is possible, but requires some contortion, assorted short or curved 13mm wrenches, practice and experience. Taking them apart is possible, but putting them back together would not be easy as the seams are folded over sheet metal that is done at the factory. I don't believe the seams can be duplicated at home, or made as tight.
As a professional mechanic, I use a smoke generating machine to find exhaust leaks. The process is to pump the exhaust system full of smoke then inspect to find leaks. Being from my area I have never seen a rotten heater box that leaked internally. That doesn't mean it can't happen, but the pipes are made from quite heavy metal. Usually the operating mechanism or external sheet metal fails first.
If there is the slightest doubt about their integrity, then you would be better off finding a very good used pair or purchase them new. They are very common and not too expensive. Your childrens health and your piece of mind is priceless. They are sold by most VW resto parts vendors.
It is just as important that there are no oil leaks from the engine, especially the valve cover gaskets. Any oil that gets on them burns and smokes, and you will smell that coming from the vents. That is HC and CO, neither good to breathe.
As a professional mechanic, I use a smoke generating machine to find exhaust leaks. The process is to pump the exhaust system full of smoke then inspect to find leaks. Being from my area I have never seen a rotten heater box that leaked internally. That doesn't mean it can't happen, but the pipes are made from quite heavy metal. Usually the operating mechanism or external sheet metal fails first.
If there is the slightest doubt about their integrity, then you would be better off finding a very good used pair or purchase them new. They are very common and not too expensive. Your childrens health and your piece of mind is priceless. They are sold by most VW resto parts vendors.
It is just as important that there are no oil leaks from the engine, especially the valve cover gaskets. Any oil that gets on them burns and smokes, and you will smell that coming from the vents. That is HC and CO, neither good to breathe.
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fatalifeaten
- Senior Member
- Posts: 512
- Joined: Sun Feb 03, 2008 12:05 am
- Location: The 480
Another couple of tips.
if you're going to take them off, get the copper exhaust gaskets instead of the thin metal sandwich ones. They'll last longer, seal better, and you can reuse them. Also, swap those pesky 13mm nuts for 11mm barrel nuts. They're a dream to install and remove compared to the stock 13's.
if you're going to take them off, get the copper exhaust gaskets instead of the thin metal sandwich ones. They'll last longer, seal better, and you can reuse them. Also, swap those pesky 13mm nuts for 11mm barrel nuts. They're a dream to install and remove compared to the stock 13's.
Thanks Guys!
Thanks, Guys! Good advice all around! I'm going to try the smoke trick with some brightly colored smoke bombs left over from the 4th of July and see if any finds it's way inside- and will steer clear of prying on them to peek inside.
On a related topic...
So I'm peering down into the heat exchangers from above at the rear of the engine compartment with the fresh air hoses disconnected. There is a thin 1/4 in high lip all the way around the opening where the heater tube "barrels" for lack of a better word- nestle in and provide a firm spot to clamp he fresh air tubes to. But beneath that, the opening into the actual heat exchanger area that all the air has to be forced through? Isn't anywhere near the full 50mm or 2in of the system everywhere else- it's only about the diameter of a penny. Why the obstruction? Can I take a dremmel tool and grind away at that opening until it's almost as wide as the tubes everywhere else, increase my airflow and heat and lower all the backpressure caused by the obstruction? Is there an important reason that's restricted so far? For lack of a better description, it looks like a giant fender washer lying in there flat- but is all one part of the entire piece.
I think I know what you're talking about. I recall seeing something like this on replacement mufflers, but I don't know why a restriction is necessary. From what I can remember I thought you can take them out of the muffler fresh air fitting by prying them up with a screwdriver. You say they are integral with the muffler? I can't find any pictures for reference, so if you could post one that would sure help a lot.
No reason not to take them out if you can or enlarge the holes to allow full air flow the heater boxes.
No reason not to take them out if you can or enlarge the holes to allow full air flow the heater boxes.
Hey! Whadya' know?
Hey! Whadya' know? At one time, before they had rusted in, I think they WERE just supposed to pop right out. In fact, once I got them pried out today and scratched down through the rust? They are stamped "REMOVE BEFORE INSTALLATION, VOR MONTARE ENTFERNEN" Bet the heat will work 10 times better, now! I wonder how many of these things were left in other people's bugs? Sure hope there aren't two more hidden in the other end that I can't see!