Reply
 
Thread Tools Search this Thread Display Modes
 
Old 07-05-2022, 11:33 AM   #1
Member
 
City: Greece
Join Date: Jun 2022
Posts: 5
Onan Generator 13.5kW

On a Trader 57’ with an Onan MDKBD 13.5kW Generator. Having an issue with it. Has only been running for 50/60mins then cuts out (with no power load) - presents as Error 58. Seems to over-heat.

We’ve checked generator, coolant and bled out air-locks. Seems to start OK when cold just doesn’t run for long.

Also checked water intake and cleaned that. Then (earlier today) only ran for 2 mins now showing Error 7.

Any ideas much appreciated.
charleshett is offline   Reply With Quote
Old 07-05-2022, 11:48 AM   #2
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in the Great Lakes
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 11,096
When you say, "It seems to over-heat", do the mechanical gauges say the engine is over heating or is that the error code?

If the mechanical gauges show the temperature within operating range, you may have one of the temperature sensors in the auto shutdown circuit going bad. There should be a sensor for coolant temperature and one for exhaust temperature.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is online now   Reply With Quote
Old 07-05-2022, 12:03 PM   #3
Member
 
City: Greece
Join Date: Jun 2022
Posts: 5
Quote:
Originally Posted by O C Diver View Post
When you say, "It seems to over-heat", do the mechanical gauges say the engine is over heating or is that the error code?

If the mechanical gauges show the temperature within operating range, you may have one of the temperature sensors in the auto shutdown circuit going bad. There should be a sensor for coolant temperature and one for exhaust temperature.

Ted
It was from the Error Code. We’ve check raw water strainer and can see a 1-way valve before the water pump. We think the 1-Way valve not operating and will bypass that.

Any ideas on why there is a 1-way valve?
charleshett is offline   Reply With Quote
Old 07-05-2022, 12:13 PM   #4
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in the Great Lakes
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 11,096
Before bypasing the one way valve, run the generator and look for water existing the exhaust on the hull. The manual should have a specification for how many gallons per minutes should be passing through the raw water system. Also, you should be able to see water flowing through the seawater strainer.

If you can put your hand in the water of the exhaust, it shouldn't be hot without and electrical load.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is online now   Reply With Quote
Old 07-05-2022, 03:07 PM   #5
Member
 
City: Greece
Join Date: Jun 2022
Posts: 5
We’ve had a v.hot hour in the engine room and the Error7 sorted. (Removed faulty 1-way valve & short pipe from pump to heat transfer had a kink). Back to Error Code 58.

We’ll look at the Temp. sensors in the morning (night time here). Presumably only solution is replacement?
charleshett is offline   Reply With Quote
Old 07-05-2022, 07:14 PM   #6
Guru
 
Lepke's Avatar
 
City: Between Oregon and Alaska
Vessel Name: Charlie Harper
Vessel Model: Wheeler Shipyard 83'
Join Date: Jun 2016
Posts: 2,735
Error 7 is low raw water flow and 58 is high exhaust temp.


Check the raw water impeller. Check the flow from the seacock. Make sure the exhaust is clear where raw water enters.
Lepke is offline   Reply With Quote
Old 07-06-2022, 03:41 AM   #7
Member
 
City: Greece
Join Date: Jun 2022
Posts: 5
Thank you Ted & Lepke. We’re removing the flow sensor (sits between the raw water pump and heat exchange). We think that’s the problem. Presumably the Coolant and Exhaust sensors will activate and stop the generator if there is over-heating.
charleshett is offline   Reply With Quote
Old 07-07-2022, 01:58 PM   #8
Member
 
City: Greece
Join Date: Jun 2022
Posts: 5
We’re checking the Spindle on the WaterPump - does it turn clockwise or anti-clockwise?

Is it possible the Impellor could be installed the wrong way round (we had a new impellor installed in port recently) and if it was installed the wrong way - what would happen?
charleshett is offline   Reply With Quote
Old 07-07-2022, 03:51 PM   #9
Guru
 
O C Diver's Avatar
 
City: Fort Myers, FL... Summers in the Great Lakes
Vessel Name: Slow Hand
Vessel Model: Cherubini Independence 45
Join Date: Dec 2010
Posts: 11,096
Generally it doesn't matter which way the impeller is installed, the blades will flex in the correct direction to make the pump work properly.

How many hours are on the engine and is this the original raw water pump? Pumps wear out over time and a part in the pump called the "compression fork" can also wear down. As the fork wears down, you get reduced flow. If you've taken the cover off the pump, take and post a picture to the thread. It's much easier for us to offer opinions based on pictures.

Ted
__________________
Blog: mvslowhand.com
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters
O C Diver is online now   Reply With Quote
Old 07-07-2022, 04:33 PM   #10
Guru
 
Lepke's Avatar
 
City: Between Oregon and Alaska
Vessel Name: Charlie Harper
Vessel Model: Wheeler Shipyard 83'
Join Date: Jun 2016
Posts: 2,735
If you have the stock pump, there's a replaceable wear plate. Also the cam is replaceable, too.
Most cams can go in reversed for opposite rotation. If you've had the pump apart, make sure it's set correctly. Most raw water pumps can be used in either direction. The only change is the cam direction.
Attached Thumbnails
Water Pump.JPG  
Lepke is offline   Reply With Quote
Reply

Tags
generator, motor yacht, onan

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Trawler Port Captains
Port Captains are TF volunteers who can serve as local guides or assist with local arrangements and information. Search below to locate Port Captains near your destination. To learn more about this program read here: TF Port Captain Program





All times are GMT -5. The time now is 03:04 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012