1GM10 stalling when put into gear

[greggron]

Boat now back in after winter ashore, and motor, (Yanmar 1GM10) reluctant to start but did so eventually. But now it seems to be a pattern that it does not start easily – 4x10 sec on the starting button when cold, but more worrying is that it dies when put into gear even when run for ~5 mins in neutral with some revs higher than tickover. It will run in gear if left for longer (~15 mins) to warm.

I should point out that last season it was running fine, started easily and a few minutes in neutral, she would slip into gear and pick up without a hitch.

Causes I have eliminated:
• Blocked exhaust
o

have taken elbow off and inspected – a bit sooty inside but no real compromise of the inner diameter. Structure in good nick
o have taken off rubber exhaust pipe to check for delamination – clean and in good condition
o rinsed through wet exhaust box – grubby bits in water but otherwise nothing
o exhaust from box to external – clean as a whistle
o exhaust outlet from engine – some carbon build up but nothing too much
​

• Blocked air intake
o

New air filter fitted over the winter but phenomenon occurs with no filter fitted
​

• Blocked injector
o

Put a high dilution of injector cleaner in tank
o Once started, and engine warm went for Italian tune up, full throttle for 15 mins (have now done that x3). Happy to push us along at hull speed with no black smoke. No rev counter so cannot report max revs
o Bled fuel system and changed secondary fuel filter, glass on primary filter shows clear fuel, no water.
Engine is now freeing up after running at high revs under load, but stalling when put into gear remains when engine started from cool.
​

What have I missed?
What other causes might there be?
What would your next move be?
Anyone recommend an outfit that can service the injector in Gosport/Hardway area?

TIA

 

[Aardee]

Is there any untoward resistance in the shaft/ gearbox? - It's a long shot but it might be stalling because it's struggling to get the prop turning.

 

[Len Ingalls]

Just a possibility to consider. Since it appeared after winter storage & you say it starts hard-

possible low compression due to rusty intake or exhaust valve seat/face

sticky valve not closing fully

stuck piston ring
Remedy-check compression

Cheers/Len

 

[greggron]

Is there any untoward resistance in the shaft/ gearbox? - It's a long shot but it might be stalling because it's struggling to get the prop turning.

Thanks

That seems OK - prop shaft rotate freely by hand in neutral unless there's a gearbox problem...

 

[greggron]

Just a possibility to consider. Since it appeared after winter storage & you say it starts hard-

possible low compression due to rusty intake or exhaust valve seat/face

sticky valve not closing fully

stuck piston ring
Remedy-check compression

Cheers/Len

Thanks - I'll try hand cranking next time I am there to see how much resistance there is. Any easy remedies without taking the motor apart?

 

[pampas]

let go the haft and try the gear box Ahead & astern without the prop.

 

[Len Ingalls]

Thanks - I'll try hand cranking next time I am there to see how much resistance there is. Any easy remedies without taking the motor apart?

Detecting low compression without using a compression gauge inserted in injector port(remove injector) is "iffy",but you may here a pop or whoosh in the intake or exhaust at wrong time,during compression stroke.This would indicate a valve not seating fully.If so,next step is remove valve cover & check valve movement & gap.A sticky valve should show excess valve clearance.Using a wood block,tapping GENTLY on the rocker of the sticky valve may clear it.
I'm not much of a believer in magic potions,but squirt penetrating oil into cyl. thru injector port,letting it sit for awhile,then turning by hand-repeat if necessary.
This may clear a stuck piston ring also.
Next step would be cyl. head removal.

Before you remove head,try to eliminate all other possibilities,as other posters recommend.

Good luck/Len

 

[greggron]

let go the haft and try the gear box Ahead & astern without the prop.

Hadn't thought of that - thanks

 

[greggron]

Detecting low compression without using a compression gauge inserted in injector port(remove injector) is "iffy",but you may here a pop or whoosh in the intake or exhaust at wrong time,during compression stroke.This would indicate a valve not seating fully.If so,next step is remove valve cover & check valve movement & gap.A sticky valve should show excess valve clearance.Using a wood block,tapping GENTLY on the rocker of the sticky valve may clear it.
I'm not much of a believer in magic potions,but squirt penetrating oil into cyl. thru injector port,letting it sit for awhile,then turning by hand-repeat if necessary.
This may clear a stuck piston ring also.
Next step would be cyl. head removal.

Before you remove head,try to eliminate all other possibilities,as other posters recommend.

Good luck/Len

Thanks - just the sort of practical advice I'm looking for.

 

[Len Ingalls]

One other thot-how old is your fuel?Has it lost oomph? Adding a bit of kerosene could help that,but go lightly.

 

[greggron]

One other thot-how old is your fuel?Has it lost oomph? Adding a bit of kerosene could help that,but go lightly.

The tank was filled at the end of last season (Oct) to reduce condensation in the tank over winter. I didn't think diesel went off?

 

[Len Ingalls]

http://www.yanmarmarine.eu/theme/ya...manual/1GM10-OM/1GM10_OPERATION MANUAL_en.pdf

 

[yachtorion]

Long shot but worth a go - fuel system not primed properly, bit of air in it causing poor fuel flow? I had a similar set of symptoms on my old Yanmar once and that's what it turned out to be....

 

[greggron]

Thanks - I have that and the service manual - were you thinking of any page in particular?

 

[greggron]

Long shot but worth a go - fuel system not primed properly, bit of air in it causing poor fuel flow? I had a similar set of symptoms on my old Yanmar once and that's what it turned out to be....

Thanks - flow seemed OK when bled but I can re-visit

 

[Len Ingalls]

Thanks - I have that and the service manual - were you thinking of any page in particular?

Nope-just passing along.

Sounds like ur fuel quality is good-just grasping straws.
Diesel does go "thick" after a year or so,plus we have another problem over here due to cold climate. They change the mix for the winter by adding some lighter D1 to the "summer" D2,so it won't gel in the cold.No way will a furnace or diesel start on D2 in really cold wx,so if my tank is filled with "summer D2" & I want to start my eng. in cold wx.-no go without adding some kero,or filling with "winterD2 very late in fall. Oh well.

 

[greggron]

The problem is now fixed.

At the end of last season I removed the elbow and exhaust from it to check their condition. Both were fine. But when the elbow was reattached, the rubber exhaust and the engine stop cable became twisted together. As a result, the stop cable was under just enough tension to affect starting and causing the engine to stall when moved into gear. Spotted the possible cause at the end of the last outing when the engine was warm, so of course could not test properly until today. When engine was stone cold.

Appears to be sorted.

Thanks for everyone's advice. Just shows, sometimes it's the simplest of things.

 

[Len Ingalls]

Glad to hear! Cheers/Len

 

[stephennoble]

Great news, I always like to see a reason for an issue. I worries me when something appears to fix itself! I have been watching with interest as I also have a 1GM 10. One thing I have learnt in life and on boats is 99% of problems are connections! In this case your gear connection, exhaust hose and fuel cut out. :encouragement:

 

[greggron]

On the upside, it did mean that the motor received a good looking at and passed muster. V reassuring.