IGM10 Wont start and white smoke out air intake

[kagallag]

Hi, my IGM10 wont start after winter lay up. The engine is turning but white smoke is coming from air intake. It is probably turning in reverse for some reason. My batteries are at >12V but I know at least 1 cell on main starter is bad and battery was almost fully discharged before C charged it again. Would this battery have insufficient current to start ? Incidently what is the minimum size of starter battery for this engine ?
Thanks

 

[WindermereColvic]

Battery connected the correct way round?
Duno if it would work if it wasn’t, but if the engine is turning over, it would seem to be turning the wrong way. If its just the odd puff of white smoke, it might just be the engine running backwards for a turn 'bouncing off the compression', especially if the battery is low.

 

[NUTMEG]

Stuck inlet valve? White smoke could be atomised diesel blowing back. Does she sound like there is compression, or is it spinning freely, as if there is little/no resistance? Quick check would be to decompress with the lever and see if it makes any difference. No difference then no compression then possible stuck valve. Just a thought.

 

[kagallag]

thanks Steve but there is compression

 

[NorthUp]

exhaust outlet plugged/ valve closed?

 

[NUTMEG]

Hm, tricky one. In theory the only way anything can blow back out of the air intake is for the inlet vave to be stuck or leaking. In the olden days I was an agriculural engineer and sometimes with single cylinder grass cutting equipment it was not unusual to get stuck valves after a long layup. I can not imagine the battery is wired up back to front. The pos and neg terminals are different sizes after all. Sorry mate, stumped I am afraid.

 

[KenMcCulloch]

It is possible to start one of these engines in reverse but it's a bounce-back effect rather than the starter running in reverse. You need a 200CCA battery, that's not very big.

 

[kagallag]

IGM10 inlet valve

hi out there, could a novice access/remove the inlet valve on a Yanmar IGM10 to see if its stuck ?

 

[NUTMEG]

No mystery mate. Remove the rocker cover and turn it over by hand with the starting handle, bit of a bugger getting it over the compression hump though. If the inlet valve is stuck it will not move up and down! Good luck.

 

[Niander]

bit of a bugger getting it over the compression hump though....easy take out the injector

 

[NorthUp]

Free

workshop manual here- http://www.motoren.ath.cx/menus/yanmar.php

 

[misterg]

hi out there, could a novice access/remove the inlet valve on a Yanmar IGM10 to see if its stuck ?

If you've got compression, then the inlet valve isn't stuck.

...but I know at least 1 cell on main starter is bad and battery was almost fully discharged before C charged it again...

1) How come one cell is bad? If this is the case, then there may not be enough volts to spin the engine over fast enough to start - you could get atomised diesel out of the inlet as the engine bounced back off compression when you released the starter.

2) Silly question: Did 'C' connect the charger to the battery the right way round? (It is possible to charge a battery 'backwards'. My uncle Fred did it to a tractor battery years ago...) Check with a multimeter. (edit - this may or may not effect starter rotation, depending on how the starter windings are connected).

Might be worth borrowing a fresh battery to eliminate these possibilities.

0.02p

Andy

 

[Topcat47]

I'm looking into replacing my starting battery with a smaller AGM motorbike battery. I've been advised that the reccomended starter battery is 60AH ( a bit bigger than the 12AH on my Bonnie ).

TRY ANOTHER BATTERY before spannering the engine (I'd nick the one from my wife's car for a morning). Don't bother trying to jump-start it with one of those wee pack thingies as they rather depend on the battery being good, just low on charge, rather than creamed.

 

[misterg]

2) Silly question: Did 'C' connect the charger to the battery the right way round? (It is possible to charge a battery 'backwards'. My uncle Fred did it to a tractor battery years ago...) Check with a multimeter. (edit - this may or may not effect starter rotation, depending on how the starter windings are connected).

Doh! Even if the starter did run backwards, it couldn't start the engine (spragg clutches, etc.) - Ignore that comment!

Another daft question: Have you tried bleeding the fuel system?

Andy

 

[pete]

My (normally high compression) 1gm10 suffered poor compression after this winters lay up I checked it with the starting handle.I put it down to slight rust on the inlet valve seat which would cause your symptoms (valve not completely sealing). With a bit of oil dripped up the air inlet onto the valve stem and a bit of cranking it soon started and the compression is back to normal now. with the engine starting easily every time.

If you are afloat turn off the engine sea cock before cranking so as not to flood the engine.
Pete

 

[Bilgediver]

thanks Steve but there is compression

In this case it is probably as Ken has said...Bounce Back off compression due to slow starter speed with the burnt gases coming out via the opening inlet valve.

Check you have good battery and connections including the negative earth return.

 

[magic-martinh]

Agree, sounds like vapour after bounce back. I have 75Ah on my 1GM10. If you drop the decomp lever and you can't drive it through compression then it sounds like battery replacement time. On mine it is a struggle, for me, to keep hand cranking after dropping the decomp lever, but it is do-able. Good luck.

 

[rob2]

I found with a 2GM that the battery voltage was critical if the engine hadn't been started for a while (it had no decompressors). The explanation I was given was that the Yanmars use a fuel-rich cold starting regime, not pre-heaters (glowplugs) and until the bore has been sealed by oil circulation it can't quite fire up. With a good battery, about twenty seconds on the starter would get it spluttering into life. Some people advocate blowing a hot air gun into the air intake for the first start, could get exciting if that vapour got to the element, though.

I agree it sounds like you need a new battery, or at least borrow one whilst you get the engine going. That will also give you some reserve capacity should you have to bleed the fuel system (mush easier done by cranking over on the starter). Whatever you do, please don't use Easy Start, the force of the stuff does no good to your not yet oiled bearings!

Rob.

 

[steve28]

is the smoke puffing out whilst its cranking or once you have stopped ?

Steve

 

[wiggy]

I've had exactly the same problem (excluding battery issue). Mine used to start backwards and I found that starting with no throttle solved the problem even in the cold, once running add some revs. If the battery is knackered get out the handle and start with that, it's pretty easy with the decompressor.