Engine wont start!

[PCUK]

Give the starter motor 24 volts for a few turns, it won't hurt the starter motor but will tell you whether the slow turning is your problem.

 

[srm]

Thanks. I'm starting to wonder if it something like this. How did you narrow it down to the starter motor?

I usually got the engine to start, but it took extended cranking and sometimes quick start spray. Extended cranking is bad for the starter motor and quick start does not do the engine any good. Once started it would run smoothly and no problems so all other systems OK. Initially fitted new bearings to the starter motor which improved things. Then got a none Yanmar replacement from eBay and had no further problems. All this was during the winter in Orkney so engine was cold (<10C) when starting.

 

[Beneteau381]

Looks like I'm not going to get her going this weekend. I'm wondering now.what the next step is. Remove injectors maybe. I've never had them looked at. But I don't want to break anything getting them out.
Maybe i need to get someone on board to have a look first.

If you take the injectors out without using the special tool then you are in for a world of pain!

OK but what to to try next? System bled. Lift pump ok.

It hasn’t been bled properly. The little spurt coming from the injector is not enough

Thanks. This is useful. Was using wd40 on advice it is less aggressive but your approach will help with troubleshooting..

wd40 no longer works as a starting agent, the propellant used to be propane which would fire the engine, that no longer is the case. Use ether as an act of desperation OR brake cleaner also works.

 

[oldmanofthehills]

I usually got the engine to start, but it took extended cranking and sometimes quick start spray. Extended cranking is bad for the starter motor and quick start does not do the engine any good.

Quick start gives the engine a jolt - so does the starter really but without the heat burst on the piston- but the real issue is lack of lubrication. So crank it over and get oil flowing first. If it wont ever start then excess wear due to lack of lube on quick start is the least of your issue. Get lube running with brief crank over and it might even run feeer and start

 

[PCUK]

24 volts will start it if the problem is slow cranking. Experience is always better than opinions!

 

[38mess]

24 volts will start it if the problem is slow cranking. Experience is always better than opinions!

Agree, done this a few times and it works. Also bad earth's around the boat doesn't help. When mine started cranking slow it turned out to be a bad connection on the 1-2-both switch

 

[Mister E]

Any news on the starting?

 

[stu9000]

Thanks all. Yard looked at it today.Could be slow cranking but he says looks like not enough fuel getting to injectors. Will know more next week.

 

[Mister E]

I have a similar problem with a Nuffield tractor.
The filters were changed and the system bled but now the lift pump is leaking air.
This is not uncommon as the lift pump when operated by hand diaphragm moves a greater distance and can split or not work properly.

 

[srm]

On my last boat I put an electric fuel pump with its own switch in the line before the engine. Under normal circumstances and to bleed the primary filters it is not needed, but it helps with bleeding the engine filter (and injectors if required). This was after the manual pump on the engine suffered a split diaphragm.

 

[Daydream believer]

Buy a diesel bellows & put in the fuel line. This will force fuel through the system & you should hear it as it goes back in to the fuel tank. Do that for a good few pumps to get a really good flow of fuel round to remove all air before any final bleed at injectors. That way you do not have to rely on using the lift pump which takes ages & often does not move much fuel.Also you do not b..ger the starter up by constant turning the engine over,& flatten the batteries, which is really a big no no.
a common issue is slow start speed & lack of fuel at the injectors.

 

[stu9000]

The yard got it going. Thanks Blackwater Marina. They said there was a lot of air in the system. Starter battery also cranking a bit slow. Stop lever may not have been fully returning when t pushed down.

Battery may have been damaged by kids isolating it and it then getting left for a couple of weeks. I tried a repairing pulse charge when boat was ashore. I've also got over 400 ah of leisure battery to bridge to. Would leisure batteries crank slower than a starter battery,? But will get a new one anyway.

I checked the workshop manual as the last time I had to bleed an engine it was a MD7a . I'm slightly embarrassed to note I was bleeding to the injector pumps and not to the injectors themselves. So no wonder there was still air. Lesson learned.

When I was last on board i did check the t stop lever and the lever on the engine after advice in this forum. I need to eyeball it again but it seems to be ok on last inspection. Maybe a new return spring is necessary.

My guess is poor bleeding technique and maybe slightly slow cranking was to blame.

I'm tempted to fit an electric fuel pump to help with bleeding but I want to eyeball things next weekend before I do anything else.

 

[Mister E]

Thank you for the feedback, others might find it useful in the future.
An electric pump can save the need to bleed the injectors but as you say does not replace proper technique.

Please to hear it is now running.

 

[Beneteau381]

The yard got it going. Thanks Blackwater Marina. They said there was a lot of air in the system. Starter battery also cranking a bit slow. Stop lever may not have been fully returning when t pushed down.

Battery may have been damaged by kids isolating it and it then getting left for a couple of weeks. I tried a repairing pulse charge when boat was ashore. I've also got over 400 ah of leisure battery to bridge to. Would leisure batteries crank slower than a starter battery,? But will get a new one anyway.

I checked the workshop manual as the last time I had to bleed an engine it was a MD7a . I'm slightly embarrassed to note I was bleeding to the injector pumps and not to the injectors themselves. So no wonder there was still air. Lesson learned.

When I was last on board i did check the t stop lever and the lever on the engine after advice in this forum. I need to eyeball it again but it seems to be ok on last inspection. Maybe a new return spring is necessary.

My guess is poor bleeding technique and maybe slightly slow cranking was to blame.

I'm tempted to fit an electric fuel pump to help with bleeding but I want to eyeball things next weekend before I do anything else.

Good feedback, as I said, me smarty pants, not bled properly