hard starting power line 6/1

[Halfcrazy]

I am in the process of moving my lister to its final resting place and have always had hard start issues I have the electric start and if it is below 50 deg F it just wont start without a shot of either. Here is a video that shows what mine does this is a manual start but mine acts the same way. http://www.youtube.com/watch?v=E--y-vJDP3o&feature=related

What would everyone recommend I look for when I move Thump Thump to her new home? I have checked the timing and it seems ok maybe bad rings?

[Wizard]

Timing.

Rings gap too wide or malformed or cylinder liner oval.

Is the COV plug if this IDI type is correct type?  Too low compression ratio causes hard starts.  Running is around 15:1, starting is about 18:1 or bit more but non-COV heads or a non-COV plug is fixed 17:1 compression ratio.

Valves ground in for proper sealing?

Injector spraying fine mist?  And correct pop-off pressure?

The lister is acting like it had low compression and all your work heated combustion chamber enough to get it fire after several attempts.

Also I noticed you was able to keep cranking after de-compression level was released, which is impossible when engine is in good condition that one usually is able to get one push through through compression stroke and next one or two compression stroke stops you from forced cranking because speed slowed down too much for enough momentum into flywheels.

Cheers, Wizard

[Ronmar]

Well i don't think I am cheating:) 

Mine behaves like in the video when I don't deliver enough fuel, like when I have just purged the air out of the HP line, but the injector is not fully firing in a single sustained pulse/creak, but a series of little burps(sounds like a drumroll).  If it is making smoke, it is getting hot enough to fire the fuel, but not enough fuel is being injected to produce much more than smoke...  the fact that it runs at all also indicates adequate compression.

One thing that can cause this if the HP line is completely purged of air, is if the yolk on the end of the fuel pump rack is binding, it may not be allowing the rack to fully extend.  Or perhaps the governor flyweights or sliding collar are not allowed to move to their full range.  A misadjusted governor linkage could perhaps also cause this.

When the engine is not spinning, the governor flyweights are providing no force to counter the governor spring.  This should allow the governor spring to pull the flyweights, linkage and fuel rack to it's full throttle position.  If yours is not doing this, it will be hard to start.   

[BruceM]

Ronmar raises some good starting issues that I've had in the past- if you aren't getting a nice "clank" sound out of the injector, there's no point in expecting a start.  A hairline crack in my IP banjo bolt was my culpret.  If the engine sat for a day, it would weep just enough to get an air bubble.  Even with that fixed, if I turn off the fuel at the tank, after a couple weeks, I have to unscrew the high pressure line at the IP in order to get the IP primed again.  No problem if the the supply line is left on- and there is no visible seepage.

If you haven't set your head's bump clearance via lead snippet, you should.  Mine was so far off as setup in Rajkot that I had to have the cylinder shortened !  It was very hard to start until this was fixed.

With these issues resolved, my 6/1 does start very reliably, usually on the first compression stroke.
I'm at 5600 feet elevation.

Good luck in finding your starting problem.

BruceM

[bschwartz]

When my timing is set to fire on the first crank every time, I get loud diesel knocking.  If I retard the timing to reduce the knock, I sometimes have to crank two to three times before it will take.

[veggie]

Mine acted that way until I purged that fuel system of air.
Double check the injector timing.

good luck.
veggie

PS: Is your right arm now 50% bigger than the left ?  

[Rom]

I vote for the piston clearance being wrong. My 16/2 would fire just fine on the pallet, but I voted for removing the CoVs for the set compression plugs like RA Lister intended. After doing the lead test, I found there was too much clearance, which of course means lower compression. After setting everything to the Lister spec, you would be hard pressed to not have the ole girl fire on the first revolution. 

This is why I went for an engine that was also built by Dursley, just so I have the real paperwork, and exact specs. I have heard of cases where folks with the highspeed engines get different specs that seems to depend on who answers the emails that day.

Rom

[Halfcrazy]

I should clarify again that isnt my engine but mine acts a lot like that one it will smoke white but no fire till you hit her with a touch of ether. It has at least 1-150 hours on it now and runs like a champ just next to impossible to start. I will look into all these ideas and will explore checking the clearance on the head.

[bschwartz]

Yes, my right arm is 50% bigger.
Now I just need to determine if it's from starting the lister 

[XYZER]

I have one that is experiencing the described issues.....I added an electric start and then it became hard to start . I did have the fuel off while it was in the shop getting the work done on it for the starter. It became a pig to start after that! It was a first time it hit compression it went engine. I still have not had time to sort out where the air is but I believe it to be a fuel/air issue. It starts with the starter but if you hand crank it will piss you off! The guy in the vidieo cranking that hard start oid is one good ol dude! There were no changes in bump clearance timing or anything but I did have the fuel off. Air can be a problem for sure!

[Halfcrazy]

but with hours of running fine wouldnt that eleviate air? or would it be an issue of a little bubble getting in while it sets then starting hard?

[Chris]

Don't use either. My choice of "Starter Fuild" is a rags soaked with a little gasoline/petrol held over the intake. Hard to do if you are cranking. Or about a 1/2 cap full (screw on soda/pop/coke bottle cap) just a little down the intake manifold. Enough to get it going without getting out of control.

I have used either with good results and also bad expensive results

Regards to all

Chris

[Ronmar]

but with hours of running fine wouldnt that eleviate air? or would it be an issue of a little bubble getting in while it sets then starting hard?

Yes.  It is far easier to draw in air thru a pinhole than it is to leak Fuel out.  If there is any restriction in the fuel system, say at the fuel filter, and a pinhole at the banjo input to the IP, you could draw in air as the fuel system between pump and filter might be able to come under a little vacume as the pump plunger strokes down.  

Shutting off the fuel could qlso be a cause of issues if you have a pinhole leak in the fuel line.  You run the engine and it all gets warm.  You shutdown and close the tank valve.  The system is now closed.  As it cools, the fuel contracts and puts the system under a vacume.  Under vacume, the system draws air in thru the pinhole, where it sets ready to cause issues at the next start...

[Halfcrazy]

I never shut off the fuel. I think I will go thru the engine and see what she is made of. It runs so well I can not imagine anything wrong. It will carry 3500-4000 watts with out hardly a trace of smoke.

[Carlb]

I would go through the fuel system with a fine tooth comb.  My engine would run fine once started but would act up if it sat for a few weeks with the fuel shut off.  Well the problem was that there was a very small leak in bottom of the fuel filter (maybe a few drops in a weeks time) but just enough to to pull air into the fuel filter with the fuel valve to the tank closed.  The engine would be hard to start and sometimes run for a minute and shut off.  It would be hard to restart but would run well once running.  After replacing the fuel filter and repeatedly purging the hp fuel line of any air the engine starts on the first compression stroke almost every time, even in temps in the mid 20's.  My vote is for air in the fuel system.