Your Position: Home > Other Rubber Products > Diesel Engines - When to replace Exhaust Hose? [Archive]

Diesel Engines - When to replace Exhaust Hose? [Archive]

Author: Harry

Sep. 30, 2024

Diesel Engines - When to replace Exhaust Hose? [Archive]

View Full Version : Main Diesel Engines - When to replace Exhaust Hose?

MIC supply professional and honest service.

sgharford

The only rubber I have not replaced since I bought my 43DC with Cummins Turbo 903's with about hours on them is the 6" (or so) diameter exhaust hose from the shower head to muffler to fiberglass tube going out the transom. Sure looks like a huge PIA and I'm second guessing if I should do this just for the sake of doing it. For all's I know the existing hose is original. I imagine any damage to hose would be from inside and therefore only way you know if bad is by removing it.

Is there any 'test' you can do to see if exhaust hose needs replacing without actually removing it?

rsmith

sgharford

Yep - exactly what I don't want. Thinking this is year for my big '2 week trip' on her with family (been a pipe dream for seven years, in my defense I keep procreating and baby's are no fun on extended boat trips). Seems like prudent preventive maintenance item, but man is that space tight. You know how your muscles tense up when it's 20 degrees out and you are squeezing into tight spaces, using muscles you haven't used in years, alone, in a deserted boat yard? I already know answer to my question, but I have to ask.

saltshaker

If in doubt change them. You've owned the boat long enough to warrant a change. Do you have longer hose runs or are these small pieces that couple the FRP tubes to the mufflers? The piece from the engine to the muffler should be straight forward. The ones from the muffler to the pipes or transom may be a bit of a job. If they just couple the muffler pipes and thru hull flange they may be OK. If there's any length to them I'd replace them. Make sure the mufflers are supported either from straps above or sitting on a cradle. There's a lot of weight there when they're filled with water. That's when the hose connection will fail. FYI my '74 46C had all original exhaust when I repowered in . All was in good shape except for one broken hanger. I had to cut the aft bulkhead to get to the mufflers.

MikeP

40 year old rubber hose is going to be rock hard and can split or crack. Mine are 12" and a few years ago I started getting a coating of salt spray on everything under the back deck. Turned out there was a tiny split in the hose.

That's why they make duck tape! :)

Seriously&#;I wouldn't personally replace a hose that didn't appear in need of replacing. You can observe/poke/feel around and, IMO, determine if the hose needs replacing. OTOH, it's hard to argue against replacing all old hoses. So my answer is: Do whatever you think is best!

But since you are going to be making a long trip and are asking the question, I suspect you'd be more comfortable with new hose. ;)

Cricket

Replace it with silicone hose, it will be much easier to work with than trying to get the rubber stuff back on.

sgharford

Outside of rsmith, whom I've gathered from past posts has many nautical miles under his hull, has anyone else ever had an exhaust hose give way on their main engines? Thanks for feedback on your hose Jack, and Mike your opinion is always well valued. Cricket - appreciate advice on silicon hose as getting them back on in tight spaces is one of big concerns. I really don't want to do this project, but that's not reason enough.

Finalee

Yep I had several failures. Once on a sailboat, the other on a Carver with twin 302's. Each time it was an internal failure that eventually resulted in the exhaust hose coming apart. Had to shut down the engines or sink the boat. This is actually on my to do list for the spring.

jim rosenthal

I have not had an exhaust hose fail, but I HAVE found engine seawater intake hoses that were VERY close to failure- and not that old! And they have an easier life than seawater exhaust hose. So, yeah, even though it's going to be a huge pain in the butt, they ought to be at the least very thoroughly inspected, and I suspect you'll find some that need replacing.

The silicon hose IS much better. It costs a lot, but it's worth it for the peace of mind. It comes in three temp ranges, and most of us use the blue one, which is the lowest, I think, but all you need.

And, FWIW, we used Vetus seawater intake hose when we did those. I think it is better than the competition, like Trident or Shields. The seawater hoses that were about to fail were Trident- they were disintegrating.

Boatsb

I've replaced more than a few that were cooked from loosing seawater. After restoring water they almost sank when the exhaust hose failed. If they are accessible change them. If they are not check them any way you can because they carry a lot of water and rushing back to shore when one breaks is not an option.

Spellbound

Yep -- port side exhaust hose, a knife like crack in hose that was 3-4 yrs old. Sprayed mist over portside but caught soon after it had let go. Wrapped with rescue tape, over wrapped with duck tape and brought it home next day from Marathon. 52' C with QSM's

Cricket

Think the silicone hose ratings go from black- blue-red, lowest to highest temp rating. We've only ever used the blue stuff. If the metal exhaust is cold and you're able to keep the new hose warm during install the metal will be contracted, take advantage of the winter. Also make sure to use the hose clamps with the smooth inside band so the silicone doesn't get cut.

rwappleton

We we first bought "Slow An Easy" and had completed the trip to Charleston we were enjoying an adult beverage on the dock the boat began to list slightly. My good friend looks at the boat and says " It's all that junk on the deck" So I go move it to the other side and we are still listing.

We open the hatches and there is water running over the top of the stringers (the limber holes were plugged too). We had broken several clamps but no leakage. We had blown a quarter sized hole in one of the elbows (the metal ones). When under way almost no water was making it into the bilge. As soon as the engines were shut down the water back flowed.

A quick patch job using a coke can, marine tex and several hose clamps and we were not sinking any more.

upon further inspection we found the hose in terrible shape with numerous areas close to failure. The hose is 8" with 6-71 engines. We replaced from the shower head all the way back including changing the elbows from steel to fiberglass. There is a small close out on the rear engine room bulkhead that seals the E/R but is not large enough to allow the mufflers to slide forward to change the last rubber tube. You have to cut these holes large enough to slide them forward. Making new close out was not an issue.

We decided not to go with the silicone hose as the original had lasted 35 years and that I was not going to own the boat another 35 the cost was not worth the benefit. We did go with the band type clamps and I think are worth the money. We are on year two and miles with no issues.

Not an easy job. Inspect the elbows carefully. Good Luck!

Ours is a 79 model 43DC:cool:

sgharford

Sounds like failures happen, so I'm committed to doing job and really do appreciate everyone's feedback. Rwappleton - really appreciate the heads up on potential of cutting bulkhead close out, the specific details of doing the job on same model is always a bonus. I just checked price of 8" blue silicone hose - about $120 a foot versus $65 a foot for wire reinforced rubber exhaust hose. Probably need about 10' total, so will probably splurge for blue silicone given the extra crappy nature of this job.

I think my shower head and (approximately) 60 degree elbow are original - they are made of what I assume is silicone bronze. The shower head appears from outside to be in very good shape, but the 60 degree elbow is showing a fair amount of green dusty crud around the hoses. I think I'm going to have to remove shower heads to gain necessary space and will inspect. If elbows need replacing, sounds like fiberglass elbows are the way to go - would most agree?

Timeout

Ryder Fleet Products sells a 3' section of 8" blue silicone hose for $153.98. I've found their pricing on silicone hose to be very good. http://www.ryderfleetproducts.com/purosil-burke-rubber-70-800/silicone-radiator-hose-straight-8%22x3--p-t72-

saltshaker

I've used silicone hose that I got from a truck supply store. They make a red hose with a green outer layer that's a bit more like a traditional rubber hose. Makes the hose a bit stiffer and less prone to damage. I've only used it in the freshwater side. Make sure what ever you use its certified wet exhaust hose. If you have longer hose runs consider using FRP pipe if possible. If you need new elbows or risers, go with custom FRP. Marine Manifold in Farmingdale does very nice work. I used them for some custom stainless flanges and for some exhaust pipe.

rwappleton

I want to say we used between 16 and 20 feet to do both sides. Also if you go to fiberglass elbows they will need to be cut to fit they come very long.

After you cut them to fit I was coached to reglass the ends to prevent erosison. Also put a double wrap of 1 1/2 " tape glass inside to give some extra strength where the clamps will be.

Good Luck!:cool:

saltshaker

REBrueckner

Hoses closest to the engines seem to have the greatest likelihood of internal damage not apparant from the outside....due to overheating if seawater is lost....

When I bought my YF we found the exhaust hose from one of the showerheads to the muffler about 1/3 closed due to bubbles inside the hose...looked like blackened due to overheating at some prior time.....that heat also appeared to weaken the muffler FRP nipple so I reinforced that with fiberglass resin and cloth...

SKYCHENEY

Internally they can come apart as noted. I can see all the way up my exhaust from the transom. If you look in there with a good light, you can probably tell if there are any pieces hanging off of it.

Or, maybe by the time you see that, it's already too late.:)

For more marine exhaust hoseinformation, please contact us. We will provide professional answers.

sgharford

I'm wondering if I scope the exhaust with a camera like this (http://www.amazon.com/gp/product/B00KJ5TE7G/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B007T9CTBI&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0S9BNA59V99M9XV3ZV9Q), would I be able to push it past the muffler?

The muffler is a large, straight thru, black epoxy laid behemoth. Not sure if internal baffles would block pushing camera thru all the way up to turbo if I entered thru exhaust tube on transom. Anybody ever have their muffler out and able to see straight thru it?

SKYCHENEY

sgharford

Groovy - I'm trying this route first! Will let you guys know what I find. Pretty cool, yet at same time sad, you can get a plug and play scoping camera for $30.

saltshaker

I guess it depends on what you have. My mufflers on my '74 46C had baffles and you could not see through them. Same with the new ones I put in when I repowered the boat.

sgharford

With a balmy 40 degree day yesterday I tried out the camera - it did not work. 2 Problems:

1. The viewing angle of the camera was much to narrow, maybe appropriate for 1.5" diameter drain but not an 8" tube. Only image I could get was when camera was resting on tube floor. which was maybe 1/4 of total circumference.

2. The vernatone muffler appears to be baffled in such a way as to not allow a snake to pass through.

sgharford

Undeterred by 14 degree morning Saturday, made it down to boat. Figured I would remove one riser and check condition of hose. Was surprising easy to remove riser, maybe 20 minutes. The hose and hose clamps look great, and I believe they are original. Found name tag on the hose "The Cincinnati Rubber Manufacturing Company" - they made one bad ass hose to last 40 years. Also, believe the riser is original, manufactured by "Kay Industries Detroit". Again, looks great. I do not like the looks of the 45 degree elbow however, they have allot of green funk around the welds. I was thinking of just changing the elbows, but since I'm in there I will probably do hose and clamps too. I'll need 8' of 6" diameter hose and 24 hose clamps total to get 'er done. I'm gonna mellow on it for the week before I order hose and clamps as existing ones really look ok.

jim rosenthal

I think you can get fiberglass elbows in that size, from Centek/Vernatone. They might have something you could put right in there.

Avenger

If you can sneak out of work one day bring them to the shop and we can bead-blast them so you can see how they look without the creeping green. Or run them over to Marine Manifold in Farmingdale and let Paul give them a look-see.

sgharford

I just bit the bullet and ordered Trident blue silicon exhaust hose, Shields exhaust T Bolts, and Centek exhaust elbows. After reviewing earlier posts in this thread, it boiled down to being happy I got 40 years out of them. Also, since my transom takes a beating facing wrath of bay given where I'm docked (Scrod - pretty sure this is why my trim tabs rip off - from up and down motion of waves when it gets snotty at dock), I'll sleep better knowing these 2 x 6" holes are plugged up pretty well. This project is kind of like the scratch only you notice, I would totally be pissed this season cruising knowing I could have done this project and did not.

As an aside, another reason I decided to go with this project: turns out I do Not have to replace 4 x 8d batteries. I had what I would now consider a complete POS made in china battery hydrometer - the type that looks like a turkey baster with thermometer built in for temp compensation. It was coming up red on specific gravity on most cells. Realizing this is huge PIA and questioning the quality of said tool, I picked up a good hydrometer at NAPA. All cells came up 'Fair' on this device. After setting charger to 'equalize' I now have all cells in the green for 'Good'. Oh smack am I happy I don't have to deal with that project on so many levels.

sgharford

Adding to saga, it turned out I had to replace turbo's after removing the riser's due to severe corrision at mounting flange where the 2 meet. Scrod saved my ass by coming up with aftermarket solution as the stock cummins ST-50 6 bolt flange turbo's are truly obsolete and impossible to find. I plan on doing write up of what you need to do this conversion if all goes well (tested), including instructions to pm Scrod for right turbo's and adapter's ad you cannot get them elsewhere.

So I stopped at Marine Manifold in Farmingdale, NY at 5:30 am this morning (they open at 5 am, how's that for convenient weekday hours) and met Todd. Really nice guy who does fabrication, cool to see their shop. He was pretty surprised at the relatively good condition of my original risers (Kay Industries, the original manufacturer, went out of business in early 80's). Paul, the other owner, called me at 7:30 am and thought they were in pretty good shape as well and said he would bead blast and run water thru just to make sure. I thought it was very solid of the 2 of them not to simply try and sell me new ones, especaily as these are 40 years old (Monel makes the difference I assume). It further confirms what I've heard - Marine Manifold in Farmingdale is a quality outfit. From what I gathered meeting briefly with Todd this morning, they are looking for electrolysis. Typical area's are in and around the shower head. So I will keep my fingers crossed I don't need new ones and feel better I had professionals look them over.

Glory

Scott, for what it is worth, I changed all the hoses in the ER, the 4 between the turbo and collector and the hoses(2) between the collector an the first fiberglass pipe.

To my surprise none of them had NY alarming condition.

I did use exhaust hose without wire, I don't know if the silicone hose has wire, it is much easier without wire.

Another thing to be careful about is using T clamps on fiberglass pipe, you can easily crush the fiberglass pipe.

JM

saltshaker

Use crush rings for the FRP parts and the clamps won't damage them. Glad to hear your risers are fine. You can be confident if Marine Manifold gives you the green light on yours, they really are top notch. Monel really does make a difference.

sgharford

Thanks for good wishes on expense I really did not want to encounter this year. So rare it goes this way with an old boat. I wound up using Trident Blue Silicone hoses and liberal amount of KY jelly to get them on - worked great thus far, sill have to install elbows and risers when I get risers back.

Any idea where I can get crush rings? I already purchased FRP 45 degree elbows. They look thicker on ends. I would think you would have to buy elbows with rings already installed, otherwise how would they stay in place as they have to be installed on inside, right?

Avenger

I got them from Metcalf Marine Exhaust but most of the exhaust suppliers should have them. Since I wasn't going to replace the entire exhaust system I glassed them into the old tubes while I was repairing the cracks from overclamping. New elbows came with them, but they should be easy enough to retrofit.

http://i33.tinypic.com/33wkxsh.jpg

http://i38.tinypic.com/245g36s.jpg

sgharford

Thanks for lead regarding met calf marine and pictures. Have to see which crush rings will fit elbows I bought. Perusing met calf marine website, looks like you are supposed to use "Fuchs 762" as sealer between turbo flange and riser - $172 a tube! Was thinking I would use marine grade never seize - good to about degrees, so they say. Any other, albeit less expensive, suggestions for sealing compound on this connection?

Avenger

I'll loan you some.

Boatsb

That's service. The thick black gold in the tube is not only expensive but once open has a short shelf life.

SKYCHENEY

I prefer the exhaust sealant that Caterpillar sells to the 762. It seems to work better and you can get a whole can of it for less than a small tube of the Fuchs.

Here is a pdf on it. Its made by 3M.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDoQFjAB&url=http%3A%2F%2Fwww.aoc.nrao.edu%2Fengineering%2F ElChemInventory%2FMerged%Files%BC%2FCAT%25 20high%temp.%manifold%sealer.pdf&ei=WkpHU7WFA4eC2wX494HQCA&usg=AFQjCNEnPvdr22MC32tw16syYJXd4x6OpA&bvm=bv.,d.b2I&cad=rja

Boatsb

Never heard of cat selling something cheaper. I must learn more about it. Is it compatable with cummins engines or does it cause a severe reaction>
:)

sgharford

Looks like the Cat stuff is expensive too - $140 a can from what I could find. I don't know what's wrong with me, but I find it pretty nifty that stuff like this even exists.

Thanks for recomendations, and Scrod, thanks for offer to lend me some. I'll ask guys at Marine Manifold if they can give/sell me enough to get this job done when I pick up risers before I hit you up.

Want more information on boat fuel fill hose? Feel free to contact us.

Previous: Rubber vs. Metal Expansion Joints

Next: Essential Guide to Choosing the Right Boat Corrugated Hose

Comments

Guest Posts

If you are interested in sending in a Guest Blogger Submission,welcome to write for us!

Your Name:(required)

Your Email:(required)

Subject:

Your Message:(required)

0/2000