yanmar ysm8 must it have easystart?

[culamnelson]

I have a 1968 25' sloop with this engine. It came with a can of easystart and there seems to be no other system for starting from cold . Can this be right?

[mitiempo]

You shouldn't need it. If you do use it the proper way is to spray some on a rag and hold the rag to the intake. Some use WD40 as it is less volatile.

If you give it enough throttle it should start - this time of year it is never that cold.

Old corroded wires to the starter and ground and bad connections can make this worse. When I re-wired my YSE-8 with a larger gauge wire it started much faster than with the original wiring.

[okawbow]

You probably need a new head gasket, and possibly a new injector. Might as well replace the intake and exhaust gaskets too. You can replace them yourself, or with help from a mechanic. A parts list and manual with torque values can be downloaded online. You will want to clean out the carbon on the head and piston also.

It's an easy job that I did in just 2 or 3 hours. You'll need a torque wrench, which you can borrow from some auto parts stores. Don't use ether in a diesel, or it may break rings and crack pistons.

[TQA]

Originally Posted by okawbow

You probably need a new head gasket, and possibly a new injector. Might as well replace the intake and exhaust gaskets too. You can replace them yourself, or with help from a mechanic. A parts list and manual with torque values can be downloaded online. You will want to clean out the carbon on the head and piston also.

It's an easy job that I did in just 2 or 3 hours. You'll need a torque wrench, which you can borrow from some auto parts stores. Don't use ether in a diesel, or it may break rings and crack pistons.

Please do not follow the above advice. If it aint broke dont fix it!

OK It MAY be broke but there is no evidence of that yet.

It is unlikely to be the head gasket if it had blown there would almost certainly be other symptoms esp. overheating.

It could be the injector but again there would be other symptoms, in nearly all cases, black smoke under load usually near smokescreen quantities.

First priniciples. Are you cranking for 20 seconds at full throttle when you are trying to start it.

If you are - check your RPM cranking . [white bar on crankshaft pulley and a model helicopter blade tach. is one way. ] if low battery and supply wiring to starter should be checked. for voltage drop.

If cranking RM is ok then check compression dry and wet. Best to get a diesel tech to do this. He may suggest valves or rings as the culprit and maybe just maybe the head gasket but that would be rare.

BUT it is a 43 year old engine and when you start spannering you may be opening a VERY expensive can of worms, if it runs well, without overheating or smoking I would just buy a spare can of easy start. If it aint broke dont fix it!

Oh yes worked on my first diesel about 50 years ago and still have grease under my nails.

[SloopJonB]

I had a YSM8 years ago. In the winter if it was reluctant, I'd hold the compression release open and spin it a bit with the starter, then drop the compression release and it would fire right up.

It also needs full throttle to start, then after it lights, cut it back.

You haven't said how it runs after starting - that tells a lot of stories.

[okawbow]

If it won't start without ether; it's broke....A decarb and new head gasket is a cheap and easy way to rule out a potential cause. I'm sure it needs decarbed after 40 years. I own a YSE8, which is basically the same motor. It's a very easy motor it work on. I had a leaky head gasket on mine, that did not produce any other symptoms. It just wouldn't start without ether. After starting, however, it seemed to run fine. I wasted a lot of time and effort trying a avoid fixing it properly. When I finally took it apart and fixed it, I was amazed at how easy it started. I even started it with the hand crank.

If you are having trouble starting because of cold weather; try blowing a heat gun or propane torch, into the air intake while starting. Throw the ether away.