What's my first step here?

[Baltimore Sailor]

I wasn't planning on replacing my hot section, but today I was replacing a fitting on my raw water through hull and when I pushed the rubber exhaust hose out of the way a bit my section broke in half.

In a way it was a bit of luck, because I was able to easily remove the manifold since it was no longer attached to anything! I'd also bet that the pipe had been leaking, too, and no one needs CO in the cabin.

So now I have my hot section in two nice pieces, and while the bolt ends on the flange look very clean, I don't have much hope for getting them off -- but I'll try.

The question I have is what should I do with the manifold now that it's off? Do I take it to a good all-purpose real auto shop and have them dip it or something? What kind of cleaning/testing should I have done? Does anyone know of a good shop in the Glen Burnie or Pasadena areas of Baltimore?

[edwardc]

A pressure test is the first order of business. If it leaks, no need to do anything further, just replace it. :(

Assuming it holds pressure, a good long flush & soak of the cooling jacket with white vinegar, or a shorter one with muriatic acid should clear it out.

If the gasket surface looks good, no need for a shop. Just take a drill-driven wire brush to the rest of it, give it a couple of coats of Rustolium Deep-Rust Primer, and finish with several coats of your favorite engine paint color.

As for the hot section, check out my hot section rebuild album:
http://www.moyermarine.com/forums/album.php?albumid=73

[Baltimore Sailor]

How does one pressure test a manifold off the block? Seems like there's a lot of holes to plug up. Does it require special equipment?

[Baltimore Sailor]

Never mind, I found the answer. Which is a better test: air pressure or water pressure? A water test seems easier, since you only have to block the outlet and put a hose fitting on the inlet. With air you could pump it up and get a real measurement. But does it really matter how accurate the reading is if any amount of leaking means a replacement?

[Maurice]

Hi,
I did much the same thing last Sept. Fortunately I have a bit of gear and could make another one up in about 3 hours.

Go to a plumbing store and have someone help you put together an exact copy of the hot section with black iron. Good for about 4 or 5 years....maybe more. Don't take it all apart just yet, they can line it up looking at the break lines on the metal.

Next...If you are not really familiar with heating and removing studs perhaps the same "plumber"s outfit can do it. Otherwise, take it to a machine shop. Those guys work metal. If you bring it to the wrong person they can damage the flange, swist off a stud or two...costing more money to remove. Machine shop can also tap the threads for you. Have the machine shop guy weld on a water spigot also.

My space in the compartment allowed me to assemble everything, manifold, hot section, and wrap it........then I installed it and hooked it up to the hose.

Hope this helps.

[Maurice]

In my album "Odyssey's Engine" I have a pic of my hot section on the tailgate of my truck. I used it to make the new one. If your's is at least that much together it will be a breeze.

[Baltimore Sailor]

I have the section in two nicely separated pieces. It broke right at the horizontal section after the riser. I cut the tail piece out of the exhaust hose and the rest came out with the manifold.

I don't have studs to break on my flange, it has the bolts. I'm not sure what the process is to get those out -- I'll start with soaking them with Kroil or PDBlaster or whatever the stuff is, but I don't have much hope of getting them out after 18 years. Once I twist the bolt ends off, what's the next step to pry the flange off the remnants?

[edwardc]

Never mind, I found the answer. Which is a better test: air pressure or water pressure? A water test seems easier, since you only have to block the outlet and put a hose fitting on the inlet. With air you could pump it up and get a real measurement. But does it really matter how accurate the reading is if any amount of leaking means a replacement?

The air test is better because air is less viscous than water and will leak more quickly through a small leak than water. Also, it may be hard to detect a water leak if it's inside the mainfold.

When I tested mine it was easy. I didn't even have to remove the hose fittings. I simply clamped a short piece of hose onto each end. On one of them, I clamped a dial-style tire pressure gauge. On the other, i clamped a car-tire valve stem with the base cut off. Then use a 12v tire inflator or a bicycle pump to pump it up some and listen for leaks. Leave it that way for a while and check back later to see if the pressure's holding.

[edwardc]

I don't have studs to break on my flange, it has the bolts. I'm not sure what the process is to get those out -- I'll start with soaking them with Kroil or PDBlaster or whatever the stuff is, but I don't have much hope of getting them out after 18 years. Once I twist the bolt ends off, what's the next step to pry the flange off the remnants?

If the bolt heads are in good shape you might be surprised. But you're on the right track. Repeated soakings with PBblaster, alternated with heat from a propane torch will help a lot. Then try using a 6-point socket on an impact driver. I have a battery powered one that works great for this kind of stuff. It's not as strong as an air-powered one, so there's less chance of twisting off the bolt head. When you replace them, use stainless and coat them with copper anti-seize first.

I'm going to be in Pasadena this weekend doing my bottom paint, so maybe I could help out.

If you're interested, PM me and we'll work out the details.

[Baltimore Sailor]

If the bolt heads are in good shape you might be surprised. But you're on the right track. Repeated soakings with PBblaster, alternated with heat from a propane torch will help a lot. Then try using a 6-point socket on an impact driver. I have a battery powered one that works great for this kind of stuff. It's not as strong as an air-powered one, so there's less chance of twisting off the bolt head. When you replace them, use stainless and coat them with copper anti-seize first.

I'm going to be in Pasadena this weekend doing my bottom paint, so maybe I could help out.

If you're interested, PM me and we'll work out the details.

I appreciate the offer, but I'll be in Frederick beating on the bolt heads. :D

There's an auto garage just down the hill from me that has a machine shop. If I can't get 'em with a PBblaster soaking, I'll just take it there.

Thanks anyway!

[Maurice]

It took me about 5 minutes to heat and remove the bolts / studs...have to do the same for both. I used oxy /acetylene. There's a fine touch between them turning out or twisting off...and there is a knack to it.

Are you the original owner of the boat? The hot exhaust may not be as old as you think and the heads of the bolts will deteriorate with the heat...much the same as manifold bolts /studs on a car.

I would take it to someone to remove them with heat as you were thinking. Once it is all apart you can make up what you need. My advice on that is to build it off the boat then install it. Ensure every pipe thread is tightened with pipe wrenchs...I used some pipe dope and never had any leaks.

I also used 2 packages of the wrap material to absorb the heat and then wraped some stainless steel wire around the whole length just to keep it all together.

This is not a major. The hardest part is the proper disassembly of the flange and manifold, tap it, new bolts or studs. The rest you can make up

[Maurice]

I just did this last Sept...if you would like to give me a call it's not problem.
902 461 1228.

[Baltimore Sailor]

I don't have a bench to put it on that would provide the leverage I'll need for this project. All I have is a small vise that isn't even close.

I'll drop this off at the machine shop at the bottom of the hill and see what they think of it. They do a lot of work on dragsters, so I'd think they'd have some equipment.

[sastanley]

BS,

I don't have a vice/bench setup secure enough to handle this either...believe me I tried, and my vice spun around in circles. My neighbor brought over a "Chain Vice Grip" back in 2009 when I was trying to pull my old hot section apart. We attached the hot section to the trailer hitch/ball on my '93 Grand Cherokee (any trailer ball will obviously work, I have one on my old Civic too!) and then used a pipe wrench to get things loose. What a cool tool!

I bought my own at Harbor Freight and have used it many times since..again this winter to wrench the Moyer flange off the hot section to switch from bolts to studs.

Harbor Freight calls it a "Locking Chain Clamp" - http://www.harborfreight.com/locking-chain-clamp-36813.html

[Baltimore Sailor]

The flange is off and I'm ready to move on. I dropped the manifold off at the speed shop less than a mile from my house, and he got one of the bolts out while I was there. The other was being recalcitrant, so he soaked it overnight and when I stopped by today he had it all taken apart and cleaned up for me. Only charged me $15.

Now it's parts orderin' time! That, and get the hot section made up at Home Depot this weekend, and I'll be rarin' to go again.

[sastanley]

Great work BS, you better post some pictures!!

[Baltimore Sailor]

Being mostly a speed shop, the patrons are a little more "gearhead" than the average person. There were two gentlemen of a certain age in the store when I stopped in to pick up the manifold, and when the mechanic brought it out and put it on the counter I could see their eyes widen.

After chatting with the mechanic for a bit, I started to write the check and one of the gentlemen finally broke from his curiosity: "What is that off of, anyway?" I told them it was from a Universal Atomic Four marine engine, a straight-four L-head (I think that's the right term) engine, like an old Willys. They oohed and ahhed over it for a bit, and I told them how the exhaust pipe had broken while I was working on something else. I said I was going to use black pipe ("That's what that looks like," one said, nodding at the rusted pipe still attached to the flange), while some other owners had used galvanized (both of them frowned and shook their head: "Too much smoke from burn-off!"), and some used stainless (no reaction: if anything, a bit of an eye-roll).

Moyer Marine got a shout-out as well, when one of the guys said, "It must be tough getting parts for that old engine, isn't it?" Not at all, said I -- Moyer Marine was the guru of A4 engines and carried parts from rebuilt engines to brass washers for the cooling side plate. They both nodded approvingly at that -- it's good not to let the old things die.

Today I go to the boat to measure. I think I can get more of a rise in the pipe than the old one had, at least by a couple of inches. There's not a lot of headroom in the compartment, but any gain would be a plus.

[Jesse Delanoy]

I don't know if this is any help, but there's an automotive machine shop in Pasadena right on Mountain Road shortly beyond where Route 100 ends, going toward Gibson Island - somewhere in the vicinity of the Texas Road House. I haven't used them, so I don't know if they're any good or not, but I see them on my way to Hammock Island.

Jesse Delanoy
1977 Catalina 30 "Off The Grid"
Baltimore/Pasadena, MD

[Baltimore Sailor]

Yep, I've seen them. I just took it to the guys close to home because... well, they're close to home. Heck, Cobe Marine might have been able to do it for me, too. They have some kind of shop there, and they're right on my way to White Rocks.

Thanks for the tip.

[JOHN COOKSON]

I put a union right after the manifold when I rebuilt my hot section - the original hot section didn't have one. It made lining up and final assembly on the boat a lot easier. I didn't have to remove my manifold when I rebuilt the hot secton. Just an idea - don't know if it will work for you........or you may have a union already.

Also as kind of an experiment I used TFE paste pipe dope on the pipe threads in the hope I could unscrew them later. We'll see how that works.

TRUE GRIT

[Baltimore Sailor]

I'm having trouble visualizing this. I thought a union was a length of pipe with female threads on both ends. If I have a straight section coming off the flange going into the female threads of a 90 deg. elbow, how does another union come into play, and then provide an increased amount of adjustment?

Can you post a photo or drawing?

Here's a photo of the broken section off my engine. You can see it doesn't have much of a rise, but there's not a lot of headroom for it in the first place. I might be able to add 3" to the lift, but not much more.

[ndutton]

The fitting is actually three pieces: two machined mating flanges and a threaded collar to hold it together. The machined surfaces seal dry, no sealant is used between them.

3844

[JOHN COOKSON]

On my boat there is a 6" straight run right after the flange on the manifold before the first 90 degree elbow. This is where I put the union. It doesn't look like it would work for you since you have a 90 degree street ell right after the flange.

My (perhaps misguided) reasoning with the TFE paste went like this:
The hot section failed where two dissimilar metals meant - brass & iron. Maybe next time I could replace only the section of the hot section that failed in this location. I am not sure this will work - it was only an experiment.

TRUE GRIT

[Baltimore Sailor]

I'm not going to rebuild my section the exact same as it was. It was too close to the top of the tranny box and made getting to it difficult. I have, um, boatloads of room behind the engine at that point, so I'm going to run a straight section out a bit to get some clearance.

So the purpose of the union is to let you mate the hot section to an extension off the manifold, then just tighten the union fitting a to join the pipes? That's exactly how I connect and disconnect the water lines from my pool to the pump and filter. Good idea!

[JOHN COOKSON]

You will find that lining up the new hot section in 3 dimensions is not as easy as you think it should be. The union will act as a quick disconnect while you adjust the various angles. That is how it worked for me anyway.

TRUE GRIT

[Maurice]

Hi,

I looked at the photo of your old hot exhaust. That's not a bad rise you have there. If you can get a bit more that would be great, it might give you more room to direct the piping also. That said, have a look and ensure you are not too close to the deck or bulkhead above.

There's a pic of my old one on the tailgate of my truck...in my engine album. The basic principle is to have a rise that will not allow water to free flow back into the engine...some boats have loads of room to make elaborate designs and some have no room so the design has to be short and fast as well as effective.

So basically, we are limited by available room and have to allow for access to engine / gearbox (as you mentioned). When building with pipe you do have the ability to "snake" it off to one side if it suits you better. It all depends on the room available and the ability to leave access.

What John is saying there sounds right. I didn't have much fooling around with mine...it was relatively simple.

Good Luck.

[Baltimore Sailor]

Well, I've ordered the parts: new flange, manifold gasket, water insertion sleeve, carb gaskets -- and a new set of plugs while I was at it.

I've carefully removed the old gasket from the manifold with a razor blade, and now am wondering what would be best to use to dress the face where the gasket will go. Steel wool? Fine sandpaper? Just give it a wipe with a solvent?

What suggestions does everyone have?

[hanleyclifford]

I would not worry too much about the mounting surface for the flange unless it is really bad. Are you going to go with studs and nuts in your new installation? I think it is really exciting to have the opportunity to design a new and improved exhaust hot section. After studying your picture of the hot section, I would ask the question; could you eliminate the last two 90 degree fittings and get to the same spot with two 45 degree fittings?

[Baltimore Sailor]

I hadn't thought about going with studs and nuts instead of the screws, actually. I guess it would make getting the flange off a bit easier, but I've already placed my order, and the flange comes with the screws. I suppose I could find the studs at an auto parts place somewhere. Is that the perceived advantage, removal down the line?

My plan for the rebuild is to put a 3" section straight out of the manifold and put the union that John Cookson recommended at the end of that, then another short length afterward to the first 90 deg elbow (or maybe just put the elbow right into the union). I'm going to give it another 2"-3" rise, as I've got quite a bit of room above where it was, and then I'll have to add the same amount to the drop, and maybe a bit more. The inline water injector will be at the bottom of the drop, with no elbow down there at all any more.

What were you thinking about the two 45 deg elbows -- perhaps a slope down to the fitting rather than a straight drop? I'm not quite seeing it.

[Baltimore Sailor]

Looking about for black pipe and fittings, I've noticed that there seem to be three categories in this area:

Black steel -- all straight pipe from what I've found
Black iron -- fittings
Black malleable iron -- fittings

It seems like the pipe is always black steel and the fittings are either black iron or black malleable iron. Is this the norm?

[hanleyclifford]

Black iron fittings and black steel pipe are fine together and you should buy both at your local plumbers supply - very inexpensive. I like to use street as much as possible. Every system has to be custom in our outfit but I like to be guided by the principle of having as straight a system as possible. If you could exchange two 90 degree fittings for two 45 degree fittings that's like getting rid of a 90 degree bend and in an exhaust system that is HUGE.

[Baltimore Sailor]

I'm not understanding where the 45 deg elbows would go. Are you thinking of using them from the top of the rise down to the water injection fitting? Maybe something like this?:

[hanleyclifford]

That is a good illustration. The need for the last 45 degree fitting is determined by the water lock inlet. On my installation the pipe at 45 degrees dives straight into the waterlock which has 45 degree inlet (2nd picture). I did get rid of the 45 degree swivel inlet piece on the waterlock and substituted a straight bronze barb.

[Baltimore Sailor]

Here's a photo of my new hot section, dry-fitted together. The shot's a little blurry, I think because the blank cardboard background confused the autofocus. Still, you can see I have two feet of tape measure out so you can get the scale.

I was able to use pre-cut black steel nipples to build the entire section, so I didn't have to have anything cut at Home Depot. That's a 4" nipple coming out of the flange (when I get it), then the pipe union as recommended by John Cookson. A street el makes the turn up, followed by a 6" nipple, a 90 deg elbow, a 4" nipple, a 45 deg elbow as suggested by hanleyclifford, and then a 12" nipple with a coupling to finish. The inline water injection fitting will go into the other end of the coupling and the exhaust hose attached to its other end.

All in all I think it looks pretty good. Since I didn't have to have any pipe cut, I can exchange any of the nipples if reality doesn't match my measurements when I try to install it. I might stick another 45 deg elbow at the bottom after the injector fitting if it makes a better angle with the hose.

And now, my masterpiece:

[ndutton]

Professional!!

[hanleyclifford]

Lookin' good, and smooth - I'm intrigued by the union and will be interested in how it works out. You actually could do your water injection just after the 45 bend.

[13jeff13]

I'll be there eventually with mine,, I follow all these projects and it is so nice to see the Outcomes as I too will be there eventually.:)

Thanks

Jeff

[Baltimore Sailor]

After soaking the manifold in vinegar overnight, I flushed it out with water, then started poking around to see if any bits were stuck right at the outlet. My little finger went right through the water jacket and into to the exhaust chamber -- so much for a pressure test!

http://wvu.hilltopper.net/graphics/angry_man.jpg


Next up: new manifold.

[Administrator]

Hi, Hanley:

Is that some sort of support bracket attached to the vertical portion of your system? Some of this plumbing is getting pretty hefty, and it seems to me some means of support is probably a good idea, so long as it is attached to the engine and not a bulkhead or some such.

Right?

Bill

[hanleyclifford]

Right, Bill. The black iron pipe is 2". The "headstay" and "shroud" are 3/8" stainless threaded rod. Both are attached to the engine itself.

[Administrator]

"headstay" and "shroud"

Took me a bit, but I got it!

The boys in Oshkosh could never have dreamed that this kind of thing would be going on decades later...

Really slick engineering, Hanley.

Bill

[hanleyclifford]

Here's a picture, Thatch modification and all. Note turnbuckle adjuster.

[Baltimore Sailor]

It's been a while since I updated the thread, so here's the latest: I had to deep-six all my 45 deg elbows -- there just wasn't enough room between the Vetus muffler and the end of the hot section to get the 4" of hose in there. By going back to 90 deg bends I can have 13 " of hose between the injection fitting and the muffler.

No photos to show, but I basically ended up with what I took out. I did keep the union on the first vertical section of pipe -- it gave a lot of freedom to position the rest of the section where it would be most out of the way.

All I have to do now is connect the rest of the hoses to their barbs and snug everything down. I'll get some pictures, and hopefully video of my spring startup, on Wednesday.

[Baltimore Sailor]

But I didn't get any video or photos. I connected the last of the hoses, then drained the Racor filter. No water I could see, though there was some waxy yellow/orange stuff that was trapped in the filter and came out. What would that stuff be?

After putting the filter drain plug back in, I turned on the blower, waited a few minutes, then pulled the choke and turned the key. She fired instantly, which surprised me so that I let the key go before she really got going, and she died when I let it go. I cranked her again and she fired right up, like I'd been using her every day all winter long. The new water pump put out good flow, and she might have been a little quieter, though it was hard to tell. No leaks from the new hot section, but the anti-siphon valve did have a bit of a drip. Nothing fast, more like a drip every 15 seconds or so. I shut the engine down after a few minutes and tightened the valve a bit, and then -- the horror!

Trying to get the pipe wrap on that thing is the hardest task I've ever taken on, bar none. I spent an hour and a half laying on my side trying to get it on with no gaps, but I could never figure out how to get the 90 deg elbows right. The wrap is 2 1/5" wide, so I figured a turn at the top of the elbow, a turn over the "knee" and the another turn at the bottom would do it.

Uh uh. It kept slipping off. I know that the problem is that I can't two-hand the process; I'm sure that if I could just get the leverage on it I could get that wrap to stay in place. The wrap I took off had stainless wire ties just at the ends, so I thought that securing one end would hold everything in place while I wrapped the rest, but obviously I'm missing something here.

I wish someone made a sleeve for the hot pipe, like the foam insulation wraps for your house water pipes.

If anyone has any tips on how to successfully one-hand the wrapping process, I'm all ears. I'll have at it again this weekend.

[ndutton]

The shop that does my canvas makes custom exhaust heat shields for race cars out of Nomex. Think I'll give them a call today and report back.

[roadnsky]

If anyone has any tips on how to successfully one-hand the wrapping process, I'm all ears. I'll have at it again this weekend.

Were you using the wrap that MMI sells?
I wrapped mine BEFORE I mounted the hot section.
Is that an option at this point for you?

[Baltimore Sailor]

Nope. I wanted to run it before I wrapped it so that I could see if there were any leaks. Now it's in, I gotta wrap it in place.

[ndutton]

I contacted the shop that makes the Nomex heat shields. They actually sew up a flexible heat shield system that sandwiches a number of layers including a fiberglass heat barrier capable of up to 1100 degrees F and a silicone coated Nomex outer layer (the silicone is to repel moisture). Closure can be with special high temperature Velcro or stainless wire lacing. It's similar to a sock that would fit over the hot section. Their latest project was for the headers of a Maserati.

If it sounds high tech, it is, and I believe you'll find the price a little high tech too although for what it is I didn't think it was all that awful. For a custom sock approximately the size needed for our application we're looking at $125 - $200, price dependent on features like the closure system.

[JOHN COOKSON]

I started my hot section wrap at the end that had the easiest access. I put two layers of tape on the pipe and held the whole mess in place with a single hose type clamp. Put the first layer on clockwise or counterclockwise and the second layer on the other way. You can secure the ends temporally with tape.

IMO you need at least two layers of wrap - but it gets real hot in the engine space on my boat. Said another way: if you can stand the heat forget the hot section wrap.

If you twist the tape 180 degrees where it goes around a bend it will lay flat. This is something I learned in first aid. Maybe practice somewhere access is easy before trying again on the boat?

Hope this helps.

TRUE GRIT

[Baltimore Sailor]

Two layers? Why didn't I think of that? I did think of doing it in sections, as a 15' piece of the stuff is just too much to work with. But an extra layer never crossed my mind. Twisting it at the turns sounds like a good idea too. I'll give it a try this weekend.

[edwardc]

I had no trouble with the 90 degree turns when wrapping mine. A key point was dampening the wrap with a little water which made it slightly stretchy and better able to conform. The other thing that helped was the large amount (50%) of overlap I did. This gave me more to work with on the turns, and automatically ended up with two layers of wrap over all parts of the pipe.

Of course, I did mine off of the engine, which was infinitely easier! You may want to consider that the extra time & effort to unbolt and unclamp the stack may be far less than the effort required to wrap it in-place, one-handed.

And you'll probably end up with a better result as well!

[Baltimore Sailor]

I got it all wrapped, finally. I did it in sections, wrapping the straight parts first, then going back over the elbows. Worked OK. I used electrical zip ties to secure the ends while I wrapped, then when I was done I went back and replaced the zips with stainless seizing wire.

But when I fired her up and let her get to temps, all kinds of white smoke starting coming off the pipe -- or the wrap. I used ordinary black pipe from Home Depot and the wrap was from a Cobe Marine store right down the road from my marina. It looked exactly like what came off the old section, though it had a metal foil cover on one side of the wrap, presumably to reflect heat back to the pipe.

The smoke started right near the flange and moved down the section. It almost looked as though the wrap itself was turning brown on the edges. Could it be that not all exhaust wraps are created equal, and that this is not up to the heat the A4 puts out? The stuff actually looks better than the Moyer wrap, though the only reason I didn't use the Moyer stuff is that I'd forgotten to order it, and didn't want to pay shipping for just one item, and I figured it would be easy to find locally.

Anyone else had this experience? I knew that the galvanized pipe gassed off badly when heated, but I thought black stuff did not, and I certainly didn't expect an exhaust wrap to do so. Ideas?

[Maurice]

That sounds about right so don't sweat it. As long as it was smoke (not steam from a leak) it will clear after a couple of runs. I put 2 packs of the stuff on my hot exhaust last Sept when I re-built it...it took a few good runs before I had no smoke. There is about 3 layers on mine so the more you put on the longer it takes for the "smoke to clear".

Will try to attach a few pics of mine after about a months use. Took the boat out in Oct 2010 and just put her back in on Apr 18....only about an hour's running on it so far this year.

[Baltimore Sailor]

It's a relief to hear that is normal. But I'll tell you, my resident mama duck didn't like it one bit! (She's back for her third year nesting in the starboard storage bin of my cockpit.) She bailed out until I shut it down and the smoke cleared.

[ndutton]

There are a lot of residual oils and contaminants from the manufacturing and thread cutting processes on the iron that take a little time to cook off too.