|
18-04-2017, 06:24
|
#1
|
Registered User
Join Date: Mar 2015
Posts: 92
|
Trouble getting to and keeping idle
Looks like one of my Volvo Penta D1-30 is having trouble getting to and keeping idle. It hovers or drops to ~500 rpm instead of the ~900 rpm it is set at. Occasionally cuts out all together.
Seems to do okay once we are cruising.
We were working through some issues with air in the fuel, but that seems to be doing much better, with the fuel filter only having 1/4 air, same as other engine.
What should I look at for the idle issue?
Thanks as always for the help!!
|
|
|
18-04-2017, 06:27
|
#2
|
Moderator Emeritus
Join Date: Feb 2014
Location: Seville London Eastbourne
Posts: 13,406
|
Re: Trouble getting to and keeping idle
I have a temporary secretary that has great trouble getting to and maintaining idle....
__________________
- Never test how deep the water is with both feet -
10% of conflicts are due to different opinions. 90% by the tone of voice.
Raise your words, not your voice. It is rain that grows flowers, not thunder.
|
|
|
18-04-2017, 06:42
|
#3
|
Moderator Emeritus
Join Date: Oct 2013
Location: Jacksonville/ out cruising
Boat: Island Packet 38
Posts: 31,351
|
Re: Trouble getting to and keeping idle
Air in the fuel can definitely do it, there should be no air in the filter, none.
unstable RPM, very first thing to look at is fuel delivery problems
|
|
|
18-04-2017, 06:44
|
#4
|
Registered User
Join Date: Apr 2010
Location: Shoreline, CT and Portmouth Harbor
Boat: Standfast 33, building a 65 ft Wooden Schooner
Posts: 636
|
Re: Trouble getting to and keeping idle
If it's fine when you get underway, does it stay fine if you go back into idle after cruising a little?
|
|
|
18-04-2017, 06:52
|
#5
|
Registered User
Join Date: Mar 2015
Posts: 92
|
Re: Trouble getting to and keeping idle
We had problems yesterday when we slowed down to anchor too.
We saw an improvement with the air in the fuel issue when we cut some of the hoses and redid the connections a few days ago. Only a few left that haven't been re-done.
Any other recommendations of what else to look at that might cause air in the fuel?
|
|
|
18-04-2017, 08:22
|
#6
|
Registered User
Join Date: Jul 2016
Location: Reno
Boat: Islander 36
Posts: 12
|
Re: Trouble getting to and keeping idle
I had a similar issue on my Yanmar 3YM30. Eventually I rebuilt the high pressure pump, and that solved all the issues. The HP pump must have got water in it before I purchased the boat, and the internals were rusted. No problems since.
|
|
|
18-04-2017, 08:24
|
#7
|
Registered User
Join Date: Mar 2017
Location: Sackville, New Brunswick
Boat: CAL 34-1, 1970
Posts: 23
|
Re: Trouble getting to and keeping idle
Experienced a similar issue a couple of years back. Dealt with all connections but neglected to inspect a fuel shutoff valve at the tank. There was no problem until the level of fuel in the tank was low. As the fuel pump worked I creasingly harder to draw fuel up from the bottom of the tank, the dried-out packing of the valve stem admitted air.
Removed the offending valve and the issue ended.
A fellow cruiser acquaintance this year had similar symptoms and found tank sludge at several constrictions in his fuel line. He had recently cleaned his tank and was counting on filtering to take care of the residue. Some of the sludge could not get past the hose elbows when drawn into the line by the fuel pump.
That's two more possibilities for you.
|
|
|
18-04-2017, 08:48
|
#8
|
Registered User
Join Date: Feb 2016
Location: So Cal
Boat: Lancer 44 Motor Sailer
Posts: 560
|
Re: Trouble getting to and keeping idle
Sure sounds like air in the system, the fun part is tracking down the source as it could be more than one. Process of elimination till you find the culprit.
|
|
|
18-04-2017, 09:09
|
#9
|
Registered User
Join Date: Mar 2014
Location: Tacoma, Washington, USA
Boat: Casacde 36
Posts: 596
|
Re: Trouble getting to and keeping idle
IF it is performing normally otherwise, it is unlikely to be air ingress. The engine uses a hell of a lot more fuel at cruising speed than it does at idle.
It appears more of a governor spring malfunction to me. Unfortunately, as another indicated, it means a specialist visit to the inside of the injector pump. You can R&I the pump but the inside repair is a specialist job, I'm afraid.
|
|
|
18-04-2017, 09:49
|
#10
|
Registered User
Join Date: Mar 2015
Posts: 92
|
Re: Trouble getting to and keeping idle
Should have mentioned this but it seemed to start happening around the time we got a new head gasket and heat exchanger. Perhaps something didn't get buttoned up all the way/properly?
|
|
|
18-04-2017, 10:41
|
#11
|
Registered User
Join Date: Mar 2015
Posts: 92
|
Re: Trouble getting to and keeping idle
And now it won't start at all.
|
|
|
18-04-2017, 10:49
|
#12
|
Registered User
Join Date: Jul 2016
Location: Reno
Boat: Islander 36
Posts: 12
|
Re: Trouble getting to and keeping idle
Begin at your fuel tank. Systematically loosen all hoses to see if you have fuel flow. My bet is still the high pressure injector pump. Yes, make sure the fuel tank is clean. Do you have a “Racor” type fuel filter. Check it for water. Check for air in the system All good suggestions.
|
|
|
18-04-2017, 10:59
|
#13
|
Senior Cruiser
Join Date: May 2013
Location: Oregon to Alaska
Boat: Wheeler Shipyard 83' ex USCG
Posts: 3,499
|
Re: Trouble getting to and keeping idle
Check your fuel line runs for anyplace they might rub. I've seen air pulled into the line from a wear spot before the hole is big enough to allow fuel to drip out. Also wear can cause an intermittent air problem if the line moves and occasionally uncovers the hole.
Also if you use copper fuel lines, the connection to the engine needs to be via rubber fuel line so the vibration of the engine doesn't transfer to the line.
|
|
|
19-04-2017, 08:19
|
#14
|
Registered User
Join Date: Mar 2015
Posts: 92
|
Re: Trouble getting to and keeping idle
Okay at least the reason for it not starting was that apparently I cut the hose that I redid with the hose clamp.
Doh! Not sure how I missed the leaking fuel...
Still struggles just a little to get from 500 rpm to an idle of 900 rpm.
Strangely, when I started the starboard engine, it dropped the port engine briefly back down to 500 and it struggles then before going back to 900. I believe the fuel tanks and lines are all seperate between the two engines.
|
|
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Rate This Thread |
Linear Mode
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
Advertise Here
Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
Vendor Spotlight |
|
|
|
|