Volvo Penta MD6b Cold Start System - Page 3 - SailNet Community
 1Likes
Reply
 
LinkBack Thread Tools
post #21 of 32 Old 08-06-2014 Thread Starter
Junior Member
 
Join Date: Jun 2014
Posts: 18
Thanks: 12
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Volvo Penta MD6b Cold Start System

Ok next cold start I will pump the lift pump and use full throttle and see what we get. It was last run on Sunday evening, it maybe tonight I will get down to the marina.
ScottSS is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #22 of 32 Old 08-06-2014 Thread Starter
Junior Member
 
Join Date: Jun 2014
Posts: 18
Thanks: 12
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Volvo Penta MD6b Cold Start System

Also, I looked in all the manuals and can find no description of what the cold start system does. Does it allow the pump to pump more fuel ? does it change the timing of the injection ? My engine has an automatic cold start , I have learned that the cold start system is "set" when the fuel is shut off . I need to determine what it is supposed to be doing and whether or not my engine is doing it , but can find no description or diagrams or explanations of how it is supposed to work. Since my problems are limited to cold starts , I am sure that this is an area I need to fully understand.
ScottSS is offline  
Quote Quick Reply Share with Facebook
post #23 of 32 Old 08-06-2014
Senior Member
 
jimrafford's Avatar
 
Join Date: Jan 2011
Location: ct
Posts: 649
Thanks: 1
Thanked 16 Times in 16 Posts
Rep Power: 5
 
Re: Volvo Penta MD6b Cold Start System

Please read carefully.
You are not pumping the lift pump. You are pulling out the engine stop control to the stop position and pushing it back in to the run position.
Jim

S/V Deja Vu
CS 40
jimrafford is offline  
Quote Quick Reply Share with Facebook
post #24 of 32 Old 08-06-2014 Thread Starter
Junior Member
 
Join Date: Jun 2014
Posts: 18
Thanks: 12
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Volvo Penta MD6b Cold Start System

thank you Jim

I think I've got it right I'm pulling the fuel stop all the way out and letting it go back in.
I'm also pumping the lift pump just in case. I have the throttle all the way out to full throttle. The routine is it cranks about 5 seconds and nothing happens and then she will start to fire almost like one cylinder is firing. It cranks much faster when it starts to fire and I get some exhaust. After 5 to 10 seconds of that I stop cranking and wait 5 minutes. I have done this about 5 times so far.
ScottSS is offline  
Quote Quick Reply Share with Facebook
post #25 of 32 Old 08-07-2014
Senior Member
 
jimrafford's Avatar
 
Join Date: Jan 2011
Location: ct
Posts: 649
Thanks: 1
Thanked 16 Times in 16 Posts
Rep Power: 5
 
Re: Volvo Penta MD6b Cold Start System

Within 5 - 10 secs. of turning over the motor should be running.
Jim
christian.hess likes this.

S/V Deja Vu
CS 40
jimrafford is offline  
Quote Quick Reply Share with Facebook
post #26 of 32 Old 08-07-2014
merit 25 solo "er"
 
christian.hess's Avatar
 
Join Date: Sep 2013
Location: Columbus, Ga
Posts: 4,581
Thanks: 189
Thanked 189 Times in 184 Posts
Rep Power: 2
 
Re: Volvo Penta MD6b Cold Start System

many diesels are like this...yanmar also specifies full throttle cold starts on many of its engines...

Islander 36 no longer for sale...its MINE!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Planning maiden cruise for November-December 2015 to Panama Canal! The planning begins!!!
christian.hess is offline  
Quote Quick Reply Share with Facebook
post #27 of 32 Old 08-09-2014 Thread Starter
Junior Member
 
Join Date: Jun 2014
Posts: 18
Thanks: 12
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Volvo Penta MD6b Cold Start System

yes she is really dead. I am sure the compression is not enough .
ScottSS is offline  
Quote Quick Reply Share with Facebook
post #28 of 32 Old 08-10-2014
Once known as Hartley18
 
Classic30's Avatar
 
Join Date: Aug 2007
Location: Melbourne, Australia
Posts: 4,859
Thanks: 46
Thanked 65 Times in 65 Posts
Rep Power: 10
   
Dock
Re: Volvo Penta MD6b Cold Start System

Quote:
Originally Posted by ScottSS View Post
yes she is really dead. I am sure the compression is not enough .
That might still be fixable in-situ, Scott. First thing to do in that case would be to pull the injectors, check them and do a full and accurate compression test on each cylinder - since it still could be only one cylinder with a problem.

You'll need a trusted mechanic to take you through this - and before agreeing to anything major, don't be afraid to get a second opinion.

-
"Honestly, I don't know why seamen persist in getting wrecked in some of the outlandish places they do, when they can do it in a nice place like Fiji." -- John Caldwell, "Desperate Voyage"
Classic30 is offline  
Quote Quick Reply Share with Facebook
The Following User Says Thank You to Classic30 For This Useful Post:
ScottSS (08-11-2014)
post #29 of 32 Old 08-11-2014 Thread Starter
Junior Member
 
Join Date: Jun 2014
Posts: 18
Thanks: 12
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Volvo Penta MD6b Cold Start System

Well the mystery deepens- the starter began to crank slowly and then would not turn the engine any more. I started tracing wires and felt that I had a good 12V to the solenoid so i was thinking the supply to the starter motor itself was not good- Just to check I removed the starter and took it to a shop that could test it - where it was given a clean bill of health.

I was able to determine that the crimped connection on the 12V to the solenoid was not secure. It would read continuity but with motor movement and vibration it must be intermittent. I pulled it off and soldered it. I also put the original ( now rebuilt) starter on the boat ( rebuilt by Buckeye Auto Electric in Painesville, Ohio - highly recommend for old vintage stuff like this MD6B) .

I turned the key and the motor started immediately, without hesitation. Cranked less than 2 seconds. This was after not running for a week. I started it and stopped it 10 times yesterday and motored around the river and harbor here for 4 hours, and it ran beautifully- idled down , shifted gears, up to 1500 rpm, 700 rpm idle etc. etc.. Too bad it was too windy to do any sailing. Good news was we explored up river where I had never been before because I assumed it was too shallow but we had 12-13 feet of depth all the way to an old railroad bridge and found a marina full of sailboats - !

I know the engine is old and tired- but I am at a loss as to why this wire connection would prevent it from starting except it is possible it simply turned the engine too slowly to fire.

I also changed out the oil ( still cleaning it up from the leaky lift pump diaphragm)-and added some goop from Rislone that is intended to help the rings seal .Probably only going to make me feel better but it may help a little .
ScottSS is offline  
Quote Quick Reply Share with Facebook
post #30 of 32 Old 08-11-2014 Thread Starter
Junior Member
 
Join Date: Jun 2014
Posts: 18
Thanks: 12
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Volvo Penta MD6b Cold Start System

I should add that I also took the rocker arm cover off and checked the valves cold- I could verify they were closing fully and had some clearance , but the only lash specifications I could find were for a hot engine. I could see how the de-compressor worked and made sure it was fully disengaged as well. Still back to the original question- what does the "cold start" system do ? and how does it do it ?
ScottSS is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Volvo-Penta Diesel MD5A/110S - Cold Start/Stop Control jbdoucet Diesel 4 08-06-2014 08:47 AM
volvo penta md6b fuel injectors Kahill Diesel 0 12-02-2013 08:00 PM
Volvo Penta MD6B mskinner Diesel 2 10-03-2012 04:35 PM
volvo penta md2010 won't start tahoemark Diesel 17 08-03-2012 08:47 AM
Volvo Penta MD6B reboring Ifylios72 SailNet FAQ 2 04-28-2011 04:04 PM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome