Stringer repair

[AShipShow]

I would just make a ring with some ceramic or stainless spacers to keep the exhaust away from the hull... The water jacket is a neat idea, but I'd be concerned that you're relying on water flow and if something malfunctions and the water stops flowing, that exhaust could get hot enough to catch the hull on fire.. Air gaps don't fail lol

 

[Scott Danforth]

Mad Props if his water fails, not only will he burn up the twin turbos, however that big block will eat itself too......

air gap on the exhaust coming off a turbo will need to be greater than naturally aspirated.

most likely he will be running a water pressure gauge.

bjf66 , you have to mix water with the exhaust at some point. look at your path and determine where the best mix point is to not have an exhaust full of water that runs back into the turbos when you shut down.

from your build thread, exhaust manifolds elbow down to the turbos, then I believe you come off the turbos, then back and up, thru the deck and back. I would jacket to right before the mufflers on the 15 degree down slope. when you are at rest, the nose will be up an additional 5 degrees, so that will drain the pipe and run out the mufflers and out the back of the boat, vs draining internally in the pipe and filling a hot turbo up with water

 

[AShipShow]

Mad Props if his water fails, not only will he burn up the twin turbos, however that big block will eat itself too......

air gap on the exhaust coming off a turbo will need to be greater than naturally aspirated.

most likely he will be running a water pressure gauge.

No doubt... It would all be bad if it happened.
I wonder how long it would take for an exhaust to get hot enough to catch fire to a hull?? or if it could even do it... I guess if you're pushing the motor pretty hard and with twin turbos, that exhaust is gonna get toasty, so probably could ignite poly resin no problem

 

[Scott Danforth]

No doubt... It would all be bad if it happened.
I wonder how long it would take for an exhaust to get hot enough to catch fire to a hull?? or if it could even do it... I guess if you're pushing the motor pretty hard and with twin turbos, that exhaust is gonna get toasty, so probably could ignite poly resin no problem

fuel vapor auto-ignites at about 500F (260C), which is why most of the marine motors try to keep all the hot bits cool.

rubber melts at 250F (120C)

both epoxy and poly resin get soft about 140F (60C)

 

[AShipShow]

Looks like cured poly resin self ignites at about 900°F... I'm assuming an exhaust could get that hot, since ive seen em glow red lol

 

[Scott Danforth]

each temperature has a color

I know from the thermal imaging camera of the exhaust on one of our diesel firepump drivers under full load for 4 hours was about 1900F. it burned the paint off the safety shield on the side of the power pack

 

[bjf66]

A touch of reality has set in with the exhaust, doesn't look like its that practical to route the tail pipes up through rear deck
Much easier building cars not so much stuff to think about

had a rethink
want to use the Imco powerflow plus exhaust, however the risers aren't going to work as positions the turbo in wrong location.
Therefore has 12mm stainless flange laser cut
have order 3" 90 degree elbow sch10, and will fabricate the riser then use a V-band clamp to another 90 degree elbow that mounts the T4 turbo (no need to get much bigger as too difficult to fit under hatch
This way can move the turbo around on V-band clamp to get correct position
Remembered had some imco/gentry/race aero (not sure which one) water cooled pipes on storage rack, these are new nice polish 4"/3.5" double walled water cooled pipes approx. 900mm long

From turbo centre mount position I have 1200mm distance to the transom
The turbos would be mounded back from the centre mount position 250mm depending on how the radius/pipes work out for the fabrication
The turbine housing need to be drilled for turbo pipes as bolts holes are out by 45 degree to position the water cooled pipe exhaust pipe water fitting at 12 o'clock on the pipe flange...assuming this would make a difference

This this would give me exactly whats needed with the water cooled pipes after turbos
then would need a transom mounted tail pipes to hang the mufflers, or may not need the muffler pending noise levels
waiting for sch10 S/S elbows to arrive

ahhh now can sleep better at nights without that sinking feeling

 

[bjf66]

need to make allowance for waste gate in the riser that will be fabricated

 

[bjf66]

whilst looking into exhaust, turned attention to back of transom and measuring up the transom to fit arneson trim and steering rams
The Arneson has been sitting for a while. Noticed that the tape that was positioned over cylinder port fittings had come off, so was concern that dust,and crap had got inside the cylinder
put finger over port and operated the ram, seems to hold excellent vacuum,
used some light oil to pump through the ram, there was a little dirt came out but not much

Have ordered 316 S/S 7/16"x 14 tpi threaded rod to make up the bolts to hold rams through transom, they need to be 5" long
need to make up support plates for inside of transom to spread the load of the ram

I noticed there is nylon location plug on end of ram which holds the grease into back of steering knuckle. However nylon is standing proud of the flange casting by 3mm
tried to move the nylon bush/plug using a plate through bolt holes, however it wont move any further
Therefore need to either:
- use a alum plate between the steering flange and transom to remove the step
- route a recess into transom

will need to see whether i can find someone that has experience with the arnseon surface drive as note that not all the rams are the same as there are several counting flanges in use
have had a look on web for photos however cant seem to find too many like the rams I have

 

[bjf66]

long time not visit the forum, seems we are all in lock down in stage 4 in Victoria Australia.
Work crazy busy at present,
enjoying not travelling, catching up on all the jobs around home felling trees last 3 weekends

doing the odd job on boat
have sorted out the nylon plug/collar in trim ram
has to get a new trim ram rod made as the original arneson ram rod was bent, went for hi-tensile stainless and upgraded seals so they can handle high pressure on pump if needed

cut 2 * 4" hole in transom for water cooled exhaust, turbo pipes to hang out of and have a pair of shot gun flapper exhaust if needed to hang off the end of pipes. I'm hoping the turbos being a exhaust restriction will quieten the noise a little????

 

[bjf66]

need to look at the trim and steering hoses and fittings through transom, need some long bulkhead fittings AN4 and AN6 *100mm + long to go through transom

 

[bjf66]

was going to but the transom rings, however over here is Aussie couldnt find anybody offering anything suitable
so decided to make my own out of 2mm stainless steel plate, cutting 6" and 4.5" Dia hole, wasnt easy, ended up using hole saw and 4" grinder, and rotary file
managed to purchase 3mm (1/8" ) silicone sheet and then cut the 6" and 3.5" rings from that ...fits like a glove

in photo Im still fabricating stainless exhaust so starboard pipe is on slight angle looking from back view

in weekend inside the boat to get the port exhaust tacked up

 

[bjf66]

need to look at the trim and steering hoses and fittings through transom, need some long bulkhead fittings AN4 and AN6 *100mm + long to go through transom[/QUOTE]

 

[Scott Danforth]

need to look at the trim and steering hoses and fittings through transom, need some long bulkhead fittings AN4 and AN6 *100mm + long to go through transom

[/QUOTE]

your going to have to custom make these because they dont exist on the shelf. we have make them at work for our transom lifts as the transoms on yachts vary from 2" to 6", we make them in various length

we take 3/4-10 threaded stock and drill a 1/4" hole thru the ends and put an SAE ORB port on each end to install #4 JIC fittings.

if you have access to a lathe, all you need then is the port tool and tap

 

[bjf66]

scott
thanks, I figured you were going to tell me this
just need to get on with it
cheers Brett

 

[Scott Danforth]

something like this

 

[Scott Danforth]

the other choice is to pocket out the inside of the transom somewhere and use standard length bulkheads

 

[bjf66]

scott yes thought about the pocketing out the rear of transom, but think best to leave as is, and punch a few holes through transom... a little more work at this stage is not really an issue

 

[bjf66]

K-Planes

managed to get onto nicely used set of K-planes complete with pumps, lines and trim gauges
Budget couldn't stretch to the US$3K for new set, so when these came up managed to jump on them quickly
Klanes are 14"x18"
NOW just to figure out how to mount them given I haven't much room in transom area in lower part

 

[bjf66]

I can feel some transom mods coming up