Idle question

larson260

Seaman
Joined
Dec 31, 2012
Messages
53
I have a 2015 320-CE-B (A368343) with a DPS-B. When I shift from neutral to either forward or reverse I get a loud thump. It has been like this from day one. I checked the idle speed with my Tech Mate and it is 700. The workshop manual says that the 5.7 GXI should be 600. The manual does not speciffically give the r.p.m. for the 320-CE-B. Is there any way I can lower the idle to try to get rid of the thump.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,678
Hey muc can you advise?

My thoughts is maybe something isn't right so the ECM is idling the motor higher, such as IAC, MAP, fuel pressure. Need a scanner
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,170
When you say day one, did you buy the boat new?
What lube is in the drive?
Does the idle speed change from cold to hot (hot means the engine has been under load for at least 30 minutes)?
What does the Techmate say for actual and commanded throttle %?
 

larson260

Seaman
Joined
Dec 31, 2012
Messages
53
In answer to your questions;
I bought the boat new and have five seasons on it.
Drive lube is 1141679 75w/90 syn.
Idle does not change cold to hot.
Techmate actual throttle16.2-17%, command throttle16.2-17%
Engine load at idle-29
Engine r.p.m.-642-653

My mistake at saying 700 r.p.m., that was at the dash tach. I'm thinking that the proper idle may be 650 and the clunking noise is just the way things are with my drive. It has always been like this with no change in 5 years. The drive is removed annually and tested by the marina. They gave me the lube specs.
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,170
Idle should be 600 RPM
Your throttle %'s are to high
The problem could be a calibration issue or a mechanical adjustment.
What throttle/shift control do you have? Is it analog or electronic?
With the techmate connected and engine running. Can you lower the idle speed to 600 using the idle speed test function?
 

larson260

Seaman
Joined
Dec 31, 2012
Messages
53
Electronic throttle and shift.
The idle speed test function came on at 700 and went up in 100 r.p.m. increments, it would not go down to 600.
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,170
Electronic throttle and shift.
The idle speed test function came on at 700 and went up in 100 r.p.m. increments, it would not go down to 600.

The 700 is normal at the start of the test, but you should be able to drop it to 600.
Did you get the EVC installation instructions in your owners packet? It sounds like the throttle should be recalibrated.

I’m guessing this engine has an extended warranty to 2020. Don’t know if recalibration is covered or not, have you talked to the dealer that you bought the boat from about this problem?
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,170
Oops, I missed that the engine was running. Can you run the test again. Key on engine off. While watching the % move the throttle from idle to wide open. Should see it go from 0% to 100%.
 

larson260

Seaman
Joined
Dec 31, 2012
Messages
53
O.K. went to boat and here is what I got with techmate.

Key on engine off moving throttle from idle to wide open-
TP command-50-100
TP actual 26.9
Helm throttle level 0-100

Key on engine running-
Idle speed test- lowered command r.p.m. from 700 to 600. It said 600 but only went down to 635-657 fluctuating.
 

larson260

Seaman
Joined
Dec 31, 2012
Messages
53
Forgot to mention that I did get the EVC installation instruction in my owners packet. There were actually two booklets one for the EVC-D #21462015 side mount control and one for the AKI #21461496. both booklets were just mounting instructions.
 
Top