Temporary fix for ruptured hot section?

[Mo]

Just wondering, did you make the 50 nm trip and then tackle job or are you doing it now prior to leaving?

Black iron is about the least expensive way to rebuild what you have. Would have to weld a spigot onto the downside of the riser pipe to receive the water coming from the manifold through the smaller line. Will attach a little sketch of how I did mine.

To see the sketch a little better push ALT and the + button to increase size of the page.

[Mr. Close Reach]

Thanks Mo - I think I came across this elsewhere in one of your posts. Very helpful although I don't drink Heinekein.

Have not done the Branford trip yet and hoping I won't have to (unless it gets warm again!). Ken is sending me some bits and pieces and the hardware store down the street has a good stock of black iron pipe, so I'm optimistic this will be a straightforward project. Stay tuned for the "after" pics.

[Mo]

It should go well for you....oh, and the beer is Alexander Keith's ... good stuff. Will stay tuned and see how it works out for you.

[Marian Claire]

CR: Great pic. Brings back memories. Look forward to the after pics. Dan S/V Marian Claire

[JOHN COOKSON]

The riser section (someone had plumbed in an actual riser) cracked in half in a tapped it on a cinder block.

If the piece of cinder block was acting as a spacer between the hot section and the boat and if there was no bracing on the old hot section you will have to fabricate some type of brace to hold the new hot section in place.

I used a steel stiff leg brace between the hot section and the trany. Someone used a turnbuckle system for theirs. (I think it was Hanley???) Anyway, if you need to add a brace be sure and brace the hot section to the engine or trany not the boat.

Maybe someone in the forum that has a sister ship with an A4 can give you some specific advice.

Here's what's going on: Even though you tighten all parts of the new hot section good and tight the vibration from the engine will possibly shake them loose and the hot section, especially the riser, can move around to an undesirable location.

TRUE GRIT

[ernst]

If the piece of cinder block was acting as a spacer between the hot section and the boat and if there was no bracing on the old hot section you will have to fabricate some type of brace to hold the new hot section in place.

I used a steel stiff leg brace between the hot section and the trany. Someone used a turnbuckle system for theirs. (I think it was Hanley???) Anyway, if you need to add a brace be sure and brace the hot section to the engine or trany not the boat.

Maybe someone in the forum that has a sister ship with an A4 can give you some specific advice.

Here's what's going on: Even though you tighten all parts of the new hot section good and tight the vibration from the engine will possibly shake them loose and the hot section, especially the riser, can move around to an undesirable location.

TRUE GRIT

Look in the 'Exhaust porn' thread for an example of a turnbuckle system. That one is mine but I copied it from someone else on this site, can't remember who.

You will see that my construction is very similar to your old one. Two comments:

(1) you don't need to weld anything. Just cobble together a Tee or a Wye (Y) with some reduction fittings so you can inject the water. A couple dollars at Home Depot.

(2) From the picture it seems you water injection point is very high. If you never had a problem with that it is probably OK. I would feel more comfortable with a somewhat lower location.

Good luck!

[joe_db]

My water injection is at the top of the riser. It goes up - 90 degrees - tee - down. What I did was get a nipple and force it to thread in from the other side of the reducer at the top of the tee with some JB Weld to make sure. This way the water is forced down past the point it could get back to the engine. You can do that or just buy a ready-made version from Moyer

Look in the 'Exhaust porn' thread for an example of a turnbuckle system. That one is mine but I copied it from someone else on this site, can't remember who.

You will see that my construction is very similar to your old one. Two comments:

(1) you don't need to weld anything. Just cobble together a Tee or a Wye (Y) with some reduction fittings so you can inject the water. A couple dollars at Home Depot.

(2) From the picture it seems you water injection point is very high. If you never had a problem with that it is probably OK. I would feel more comfortable with a somewhat lower location.

Good luck!

[Mr. Close Reach]

Done, mostly

Finished assembling the riser over the weekend, got it installed yesterday and just need a new section of hose to run from the heat exchanger to finish it off.

In response to the posts about bracing the section - no it was not braced before, not sure if I will add any bracing this time but I'll see how much movement I get. The new section is actually a bit lighter than the old one.

One question - my Moyer supplied fitting for the cooling inlet is 1/2" but the fitting on the actual heat exchanger (also Moyer supplied, installed by PO) seems to be 5/8" inch. Curious that they would be incompatible.

[Mo]

Nice job on the rebuild. Unfortunate that your line has different sizes on both ends. Might want to talk to the guys at MMI and I'm sure they will look into it.

On the heat exchanger, is it a npt fitting that you could screw in one with the 1/2 inch diameter or is it just a barb. If you cannot screw in a 1/2 inch fitting into the heat exchanger may have to buy a reducer for the hose. Either one isn't hard but / and I understand your point that you'd think it would just match up.

[sastanley]

I seem to have the opposite problem. I am pretty sure I have the Moyer fitting as well..& the 5/8" hose on the 'mixer' was a bit tight. Try some dish soap or some light oil maybe???? on the inside of the dry rubber hose.

[edwardc]

I had the same problem, but solved it by using two different barb sizes at the siphon break (you are going to install a siphon break, aren't you? )

[Mr. Close Reach]

I had the same problem, but solved it by using two different barb sizes at the siphon break (you are going to install a siphon break, aren't you? )

Since the water injection is below the high point, I'm not doing an anti-siphon.

[hanleyclifford]

Since the water injection is below the high point, I'm not doing an anti-siphon.

It isn't about the injection point's position on the riser; it's about the injection point relative to the water line. If you are injecting below the water line the possibility exists of a siphoning that could fill the exhaust system, then the engine, then the boat. If this configuration exists it is imperative the raw water valve be closed whenever the engine is not running or an anti siphon device should be incorporated. FWIW

[ndutton]

Hanley echoes my thoughts exactly. Consider that ALL of us with waterlifts have our water injection below the high point.

[Mr. Close Reach]

It isn't about the injection point's position on the riser; it's about the injection point relative to the water line. If you are injecting below the water line the possibility exists of a siphoning that could fill the exhaust system, then the engine, then the boat. If this configuration exists it is imperative the raw water valve be closed whenever the engine is not running or an anti siphon device should be incorporated. FWIW

Gotcha. Yes I am injecting a good bit above the WL...