Hard starting Lehman 120, again

syjos said:

Good Job!

I really don't think the cold start feature is worth spending any time on it. I've never used it on mine. Starts with throttle advanced all the way, which is what Brian will probably tell you to do. It seems like a hassle to go into the engine room to activate the cold start feature.

I keep the engine room at about 50 degrees in the winter and the engine starts slow but will start every time without using the start feature.

Click to expand...

My cold start has a button at the helm. I don’t have to go into the engine room.

Comodave said:

My cold start has a button at the helm. I don’t have to go into the engine room.

Click to expand...

How does the button at the helm activate the cold start feature? How is it connected to the injection pump? Are your Lehmans 120's?

On the 120, all there is is a button on the pump that gets pushed in to activate the cold start. I can not think of a way to push it in remotely. Maybe a solenoid?

Glad you got yours fixed. My engine doesn't lope or hunt once it actually starts so I'll be referring to thread once I get back North to see if I can fix my problem.

Tator

syjos said:

How does the button at the helm activate the cold start feature? How is it connected to the injection pump? Are your Lehmans 120's?

On the 120, all there is is a button on the pump that gets pushed in to activate the cold start. I can not think of a way to push it in remotely. Maybe a solenoid?

Click to expand...

I have not really looked at them, it works so I have left it alone. I have SP225s. I think that there is a solenoid because I hear a click when I push the button. Really have not gotten around to even looking at it since it works, I have enough other things to work on.

Comodave said:

I have not really looked at them, it works so I have left it alone. I have SP225s. I think that there is a solenoid because I hear a click when I push the button. Really have not gotten around to even looking at it since it works, I have enough other things to work on.

Click to expand...

Thanks Dave, the 225's must have a different cold start system. The injection pumps are not the same on the two engines.

I would be curious as to how your cold start is configured.

If I remember, I will try to see what it has.

Comodave said:

If I remember, I will try to see what it has.

Click to expand...

Great. Thanks in advance.

You did understand that I said if I remember...

Comodave said:

You did understand that I said if I remember...

Click to expand...

I might not remember either so don't worry.

What are we talking about?

This is a late post to an old thread, and the answer may already be obvious.

I have a single FL120. The engine will never start easily unless I use the cold start button on the injection pump. With the cold start button activated the engine starts INSTANTLY - I mean within a single revolution. Every time.

Without the button it takes maybe 20sec cranking (first run of day).

Starting with no button, but full throttle is still difficult.

This instantaneous start (with button in) makes me believe that I do not have air in the injector lines. I am away from the boat at the moment and have not experimented with the stop lever (I will do this in March).

In the meantime, any thoughts?

Thanks in advance,
Nick

Coolant heater for a couple of hours before you want the main?
The generator starts right up?

Never had a cold start on my Lehman or other diesels...so not even sure how they really work (there might be a button on my pump...but never used it and the last paint job sure seemed to make it not obvious)

Lehman always started in down to 30-40 degree temps after 4 or 5 revs with no assist....just maybe a tad of throttle.

But...seriously doubt it's air in the lines.... that would probably cause the same with full throttle...but just a guess as again...not even sure what the cold start button does internally.

The cold start/preheat feature are generally glow plug(s), very common diesels.
You were taught to hold the preheat switch down (engaged) prior to starting the generator. Do it on the main engine too.

OldDan1943 said:

The cold start/preheat feature are generally glow plug(s), very common diesels.
You were taught to hold the preheat switch down (engaged) prior to starting the generator. Do it on the main engine too.

Click to expand...

Not even close in this motor...no glow/preheat plugs at all.....

Nick F said:

This is a late post to an old thread, and the answer may already be obvious.

I have a single FL120. The engine will never start easily unless I use the cold start button on the injection pump. With the cold start button activated the engine starts INSTANTLY - I mean within a single revolution. Every time.

Without the button it takes maybe 20sec cranking (first run of day).

Starting with no button, but full throttle is still difficult.

This instantaneous start (with button in) makes me believe that I do not have air in the injector lines. I am away from the boat at the moment and have not experimented with the stop lever (I will do this in March).

In the meantime, any thoughts?

Thanks in advance,
Nick

Click to expand...

I have mechanical cable pull cold start. I think of them as a choke to assist starting, they add fuel or adjust timing, I have not discovered which. I use them on first start in winter after cold engines have sat a while.
The rest of the time I bump throttles to where 1000 rpm would be as a high idle, adjust to 1000 after start and let warm up while I untie the boat.

My twins are 51 years old, they start easy and then purrr happily.

Our last boat had the cold weather start button on it. I always used it and my engines started instantly. My understanding and I might be wrong is that it set the engines to a high idle for the start. I would push the throttles full and then push the button, then pull the throttles back to idle and push the start button. The mechanic at the yard where the boat had been for 15 years said to use it all the time so I did.

psneeld said:

Not even close in this motor...no glow/preheat plugs at all.....

Click to expand...

Then put in a coolant heater.
There are at least 2 types. Passive immersion heater and circulating water heater. If I recall correctly, there is also an air inlet heater too.
I had both the immersion and circulating heaters on my Bronco when I worked in northern Alberta. Both were AC powered

Thanks for the responses !

I can live with using the cold start button.

My post was more a desire to understand why some FL120's require use of the button and others do not. I can only guess that, in the case of my engine, the injector pump does not inject fuel into the cylinders for the first 20 seconds of cranking for some reason (air in the pump?).

I can still sleep at night, but I am naturally a curious person where things mechanical/electrical are concerned.

Have you called American Diesel?

I don't remember who and what has been addressed along the way despite skimming back over the pages of posts...sorry...

But if not, talk to Brian at American Diesel...I think the number is earlier in the thread.

The answer to my original issue (I am the OP) was the linkage for the stop solenoid. When the injector pump was rebuild and the PO installed it, the adjustment for the linkage was never looked at. Would take constant cranking until heat would build up in the cylinder and eventually light off. In the winter? Fugetaboutit. I installed the block heaters (these did help), installed new fuel filters, electric fuel pumps (one of my pumps was going bad anyway), re-timed, adjusted valves, etc etc. All no joy. Based on a very old post here in the forum, one person made a comment about checking that linkage. Besides that one comment, I have never seen it mentioned again. In any forum. Even Brian at American Diesel could not help this (his idea was the block heaters, btw)



I removed the linkage from the stop solenoid entirely. It was a colder 40 degree day, no block heaters plugged in. Typically this would be a 45 second series of cranking and worse case, ether (I know, you do not have to lecture about the harms of ether). Well, with no block heater, linkage off and cold out, it spun around maybe 1.5 times and fired off. Idled smooth for the first time when cold as well. Worked great. I readjusted the linkage where it is 2 full turns in from not stopping the motor (where it should be). I eventually took 12 full turns of adjustments out of the linkage. (after the initial 5 mentioned earlier) That is a lot.


Just wanted to re-follow-up on this in case someone missed this. I have helped three others that I know of with that same issue. Worked each time for them.

Been starting within the first or second revs each time since then, with 150 hours added to the clock.


Oh, and my cold start button does not work. Not to concerned about it.

Great feedback - thanks Redhook !

Based on a very old post here in the forum, one person made a comment about checking that linkage.

Click to expand...

I should have been more clear in this post 30 of this thread. When you did not reply I dropped the ball.

Thought the stop lever was full on or full off....so all the solenoid has to do is reach full throw.

A block heater can extend the life of older engines in cold climates for many additional years. It only needs to be on an hour or so before you start. It can be turn on by a timer or a thermostat.
I run my block heaters with a Thermocube in the winter. On at 35° and off at 45°. Or if I gonna work in the engineroom in cold weather, I leave them on over night and the ER is in the 70s by morning.

Soo-Valley said:

I should have been more clear in this post 30 of this thread. When you did not reply I dropped the ball.

Click to expand...

I assumed you were referring to the cold-start solenoid. Of which I do not have one. Sorry.

psneeld said:

Thought the stop lever was full on or full off....so all the solenoid has to do is reach full throw.

Click to expand...

Yes, and no. Apparently if your linkage is not adjusted correctly, your switch is stuck a little on the "stop" side and thus makes it much harder to start. That is what I figured out in layman's terms. Lol!

Redhook98 said:

I assumed you were referring to the cold-start solenoid. Of which I do not have one. Sorry.

Click to expand...

Yes I have both manual cable while others have solenoid on both. Each has an adjustment for the throw.

I just tried the cold start button on my 80hp Lehman for the first time yesterday, having learned about it in this thread. Wow, was that a fast start. Had to try it again today just to make sure it wasn't a fluke. My little engine has the larger Ford flywheel (100#) and turns over a little slow to begin with. Using the cold start button I couldn't even calculate how many turns before it starts. 3/4ths? Using the button makes it start much faster than it stops.

For cold starts, I'm always going to be in the engine room* anyway checking fluids, strainers, etc. I just have to remember to push the button. Actually, it doesn't stay in unless the throttle is all the way forward, so I also have to remember that before checking.

* Engine room is a bit of a stretch. I have standing headroom in my engine room, but when standing I'm eye level with the dinette seats.

Marco, I had to laugh when you described your 'stand up' engine engine room. mine is the same but my view is either the port or stbd pilot house doors.

Marco Flamingo said:

I just tried the cold start button on my 80hp Lehman for the first time yesterday, having learned about it in this thread. Wow, was that a fast start. Had to try it again today just to make sure it wasn't a fluke. My little engine has the larger Ford flywheel (100#) and turns over a little slow to begin with. Using the cold start button I couldn't even calculate how many turns before it starts. 3/4ths? Using the button makes it start much faster than it stops.

For cold starts, I'm always going to be in the engine room* anyway checking fluids, strainers, etc. I just have to remember to push the button. Actually, it doesn't stay in unless the throttle is all the way forward, so I also have to remember that before checking.

* Engine room is a bit of a stretch. I have standing headroom in my engine room, but when standing I'm eye level with the dinette seats.

Click to expand...

Mine had a push button that would lock the cold start on from the helm. Maybe you can retrofit yours???