exhaust elbow tube extensions - slash cut questions
05-20-2016, 05:52 AM
#21
Registered
iTrader: (1)
Right on Griff, glad I asked as now seeing he has stock 502MPI's, my first thing would be to check angle of drop to exhaust. If it's not enough, any motor will have issues. This was first on my mind reading his last post, and then I see you thought of the same right off the bat..
So, Kap'm, measure up and report back.
So, Kap'm, measure up and report back.
Last edited by SB; 05-20-2016 at 06:21 AM.
05-20-2016, 06:20 AM
#22
Registered
iTrader: (1)
If you don't have an angle finder, here is a good chart that shows how much drop in inches per foot equals certain degrees.
Slope Conversion
3° = 5/8 in./ft.
6° = 1¼ in./ft.
7° = 1‑7/16 in./ft. .
10° = 2‑1/8 in./ft. .
12° = 2½ in./ft.
14° = 2‑15/16 in./ft. .
19° = 4‑1/8 in./ft.
Slope Conversion
3° = 5/8 in./ft.
6° = 1¼ in./ft.
7° = 1‑7/16 in./ft. .
10° = 2‑1/8 in./ft. .
12° = 2½ in./ft.
14° = 2‑15/16 in./ft. .
19° = 4‑1/8 in./ft.
05-20-2016, 06:30 AM
#23
Registered
iTrader: (1)
If you don't have an angle finder, here is a good chart that shows how much drop in inches per foot equals certain degrees.
Slope Conversion
3° = 5/8 in./ft.
6° = 1¼ in./ft.
7° = 1‑7/16 in./ft. .
10° = 2‑1/8 in./ft. .
12° = 2½ in./ft.
14° = 2‑15/16 in./ft. .
19° = 4‑1/8 in./ft.
Model
Engine
Sterndrive
Min 9° 1-7/8 in. drop per 12 in. (305 mm) / Max 19° drop 4-1/8 in. (105 mm) per 12 in. (305 mm)
The first 18 in. (457 mm) of exhaust hose should drop the specified minimum relative to
horizontal. Thereafter, 3° of drop or 1/2 in. (13 mm) of drop per 12 in. (305 mm) relative to
horizontal is a MINIMUM requirement for the rest of the exhaust system.
• Exhaust hoses should not restrict the flow of discharge water from the elbow. The exhaust
hose cannot be bent more than 5° relative to the exhaust elbow outlet as a hot spot
in the hose will occur and burn through.
Slope Conversion
3° = 5/8 in./ft.
6° = 1¼ in./ft.
7° = 1‑7/16 in./ft. .
10° = 2‑1/8 in./ft. .
12° = 2½ in./ft.
14° = 2‑15/16 in./ft. .
19° = 4‑1/8 in./ft.
Model
Engine
Sterndrive
Min 9° 1-7/8 in. drop per 12 in. (305 mm) / Max 19° drop 4-1/8 in. (105 mm) per 12 in. (305 mm)
The first 18 in. (457 mm) of exhaust hose should drop the specified minimum relative to
horizontal. Thereafter, 3° of drop or 1/2 in. (13 mm) of drop per 12 in. (305 mm) relative to
horizontal is a MINIMUM requirement for the rest of the exhaust system.
• Exhaust hoses should not restrict the flow of discharge water from the elbow. The exhaust
hose cannot be bent more than 5° relative to the exhaust elbow outlet as a hot spot
in the hose will occur and burn through.
05-20-2016, 06:47 AM
#24
Registered
iTrader: (1)
Seems strange you're having a reversion issue with stock cams / engines.. wonder if it's a riser gasket leaking or something...
Last edited by Boatally Insane; 05-20-2016 at 09:02 AM.
05-20-2016, 07:20 AM
#25
Registered
iTrader: (1)
If you don't have an angle finder, here is a good chart that shows how much drop in inches per foot equals certain degrees.
Slope Conversion
3° = 5/8 in./ft.
6° = 1¼ in./ft.
7° = 1‑7/16 in./ft. .
10° = 2‑1/8 in./ft. .
12° = 2½ in./ft.
14° = 2‑15/16 in./ft. .
19° = 4‑1/8 in./ft.
Model
Engine
Sterndrive
Min 9° 1-7/8 in. drop per 12 in. (305 mm) / Max 19° drop 4-1/8 in. (105 mm) per 12 in. (305 mm)
The first 18 in. (457 mm) of exhaust hose should drop the specified minimum relative to
horizontal. Thereafter, 3° of drop or 1/2 in. (13 mm) of drop per 12 in. (305 mm) relative to
horizontal is a MINIMUM requirement for the rest of the exhaust system.
• Exhaust hoses should not restrict the flow of discharge water from the elbow. The exhaust
hose cannot be bent more than 5° relative to the exhaust elbow outlet as a hot spot
in the hose will occur and burn through.
Slope Conversion
3° = 5/8 in./ft.
6° = 1¼ in./ft.
7° = 1‑7/16 in./ft. .
10° = 2‑1/8 in./ft. .
12° = 2½ in./ft.
14° = 2‑15/16 in./ft. .
19° = 4‑1/8 in./ft.
Model
Engine
Sterndrive
Min 9° 1-7/8 in. drop per 12 in. (305 mm) / Max 19° drop 4-1/8 in. (105 mm) per 12 in. (305 mm)
The first 18 in. (457 mm) of exhaust hose should drop the specified minimum relative to
horizontal. Thereafter, 3° of drop or 1/2 in. (13 mm) of drop per 12 in. (305 mm) relative to
horizontal is a MINIMUM requirement for the rest of the exhaust system.
• Exhaust hoses should not restrict the flow of discharge water from the elbow. The exhaust
hose cannot be bent more than 5° relative to the exhaust elbow outlet as a hot spot
in the hose will occur and burn through.
Min rate of fall is 6* for all sterndrives other than the 8.1L (496) which min is 9*.
05-20-2016, 08:32 AM
#26
Registered
VIP MemberThread Starter
I would get a riser spacer kit to increase the angle http://www.cpperformance.com/p-14191...-93320a13.aspx
no room for higher riser spacer. high already. see pic. had to cut out gunnel to make it fit. hose angle info to follow.
PS: I know the el is not connected so don't give me no flack there. lol
[ATTACH=CONFIG]555751[/ATTACH]
05-20-2016, 08:38 AM
#27
Registered
VIP MemberThread Starter
There IS a piece of metal welded in between with a gap at the top. It's not welded solid, so it forces the majority of the water out the top of the pipe, yet allows the tails to drain when the engine is off.
The angle / location of my transom mounted tips did NOT match up to my new exhaust outlet location, so I "wallered out" the holes, installed some lengths of pipe and sealed it with 4200 and a trim ring at the transom.. so now, I don't have to worry about melting hoses..
The angle / location of my transom mounted tips did NOT match up to my new exhaust outlet location, so I "wallered out" the holes, installed some lengths of pipe and sealed it with 4200 and a trim ring at the transom.. so now, I don't have to worry about melting hoses..
Boatally Insane,
Looks like that flare would just about touch the ID of the outer pipe. How close is it??
05-20-2016, 08:51 AM
#28
Registered
VIP MemberThread Starter
SB
engine model 502mpimagBravo 1999 serial no OL315 _ _ _
[ATTACH=CONFIG]555753[/ATTACH]
[ATTACH=CONFIG]555754[/ATTACH]
PORT MOTOR
100% stock
Std alum log type manifolds.
exh hose angle 8-9 degrees
It does has some, but definitely has less condensation on elbows than the starboard. Still has some water puddling in exh manifold and on plug threads.
STARBOARD
stock except for very recent runner length cut, Eddie marine exhaust. But it did have reversion(or condensation on elbow) before the changes.
Eddie Marine alum manifolds and elbows. had condensation issues before and after the Eddie marine upgrade.
exh hose angle 17 degrees
Much more condensation than the port.
engine model 502mpimagBravo 1999 serial no OL315 _ _ _
[ATTACH=CONFIG]555753[/ATTACH]
[ATTACH=CONFIG]555754[/ATTACH]
PORT MOTOR
100% stock
Std alum log type manifolds.
exh hose angle 8-9 degrees
It does has some, but definitely has less condensation on elbows than the starboard. Still has some water puddling in exh manifold and on plug threads.
STARBOARD
stock except for very recent runner length cut, Eddie marine exhaust. But it did have reversion(or condensation on elbow) before the changes.
Eddie Marine alum manifolds and elbows. had condensation issues before and after the Eddie marine upgrade.
exh hose angle 17 degrees
Much more condensation than the port.
