1GM10 black smoke and hard to start

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kagallag

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my 1GM10 starts every time but not without a fight. After a few attempts it puff black throigh air intake so seems to be turning wrong way. If this is a timimg thing, can timimg be adjusted on a 1 cylinder 1GM10 and if so does anyone knonw how ? It has new oil and all filters (inc 3 fuel filters) and new air filter element. Batteries also fully charged from mains. /forums/images/graemlins/confused.gif
 
I am currently working through the advice I have been given to solve my poor starting 1GM.
Compression
Can you turn the engine over by hand without using the decompression lever. If you can then compression is poor. Solutions are new/reground valves and/ or new piston rings.
Fuel
Have you tried bleeding the system through and does this make any difference. Could be you have a leak that allows air into system that needs pulling through before the engine starts.
Governor
Common problem is a weak governor spring. Test this by removing oil filler cap. Put your finger in and you will find the goveror rack lever. Pull this towards you and try to start the engine. If the spring is weak then it will start straight off.
Con rod
Internal corrosion to the exhaust bend will allow water into the block. This can result in the con rod being bent (not actually bent but compressed) Even a small amount of shortening of the con rod will result in poor starting. This can be tested by removing the injector and pushing a piece of electrical solder down through the hole. By turning the engine over by hand the solder is compressed. The amount by which it is compressed i.e.. the thickness of the solder will tell you whether the rod is bent or not. I do not have the correct figure to hand but will try to edit this message when I have it.
Finally, don't make the mistake i made by asssuming that if i found 1 of these faults that there was the solution. It is possible that all of the faults exist together. It will save time and money in the long run to sort them all out at once
Good luck
 
Another source of poor starting and black smoke production is a worn injector. You end up with lots of fuel in the bore and a big puff of smoke when it finally does fire. Take it out and compare it to a picture of a good one, or take it along to you friendly local engineer and ask his opinion.
 
The Yanmar forum has a good deal on this subject - yes they can fire the wrong way in such circumstances!! Stop engine immediately or you risk water ending up in your cylinder and water dont compress much!
 
most likley cause is leaking valves, i think you will have reduced compression. check exhaust elbow first before taking head off as this could have holes in the inner liner.
 
Black smoke/poor starting could easily be an injector problem....the fuel pump and injector should be serviced together by a professional (Panda at Bursledon for instance) If the injector is worn, then fuel may leak into the cylinder.

When was yours last done?

If you're going to do a top-end overhaul (or indeed a full engine), this'd need to be done anyway so it's not dead money to try it first.
 
By the way, if you do take the head off, check the water-way before doing any work, it's a known weakness where the Waterway corodes into the head causing all sorts of expensive problems.
 
had exactly same last year, got injector serviced now fantastic, starts best with no throttle regardless of weather and never runs backwards as it did before
 
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