Lombardini Diesel

[daveNZ]

Originally Posted by daveNZ

This hard sounding engagement of forward is still a problem. Sounds like a big crunch at any revs, from neutral to forward. No issue going in to reverse.
One engineer feels the mounts are now too soft for my installation. They are absolutely correct for the engine weight, according to the graphs, but, I also have no forward thrust to the engine, on account of two flexible Centaflex ‘size 16’ couplings and associated thrust bearing and 2 metre drive shaft (forward of the thrust bearing).
So prop/prop shaft (shaft seal)/thrust bearing/flexible coupling/2 M steel shaft/flexible coupling/transmission. The change in angles over the couplings is within the 2 degrees allowed. I may try to make it as close to zero as I can.
Note there are no other supporting bearings for the steel shaft.
In my mind it may be the new mounts, or perhaps a damaged or failing drive plate in the TMC 60 mechanical transmission. I believe these are pretty durable but I know nothing else about them. I need to change the rear seal so may take it out and get it checked anyway??

Anyone have an opinion?

Think I know what’s up.
One issue was the new engine mounts had longer studs. One hit the alternator!!! One hour to remove, 1 minute to cut shorter.
So, now it is better, the sharp crash has gone, but there is still a thump, and I think it is just the resistance of the prop in the water, and soft engine mounts. So the whole setup is flexed as I move to forward gear. No problem at all going into reverse. I assume it is just less pressure from the prop due to the different bite from the prop.

[Guillaum22]

Hello Dave. I just installed a lombardini 1404 and it seems that I have exactly the same issue that you had on yours. Every thing is shaking between 700 to 950 rpm !!! Outside of this range this is perfect. I set
a compromise at 750 rpm and I have tu push immediatly up to 1000 rpm to avoid the issue.
So, I would be very happy to get in touch with you in order to get details about how you fixed this problem.
I hope you are still active and this forum.
Best wishes
Guillaume

[daveNZ]

Hi Guillaume,
Yep, still here! I’ll write a longer reply later but basically in NZ this is a common problem and we’ve improved but not totally solved it.
Dave

[Guillaum22]

Great ! Many thanks in avance !
Have a good Day
Guillaume

[daveNZ]

Hi again, sorry for the delay in replying.
Have you read this whole thread. See post #59…I changed engine mounts to a softer one. What was a sometimes violent spasm, as one person called it, has gone. There were two options for new mounts, in terms of hardness, that were recommended within the graph of engine weight and frequency that we were trying to fix. We went with the softer one.
I think my idle is now about 850rpm. My current issue is still a crunch when engaging forward, but only sometime. I’ve had a very good engineer on board recently, and he thinks it is more likely something down the back, bearings, etc. I’m not 100% convinced and might drop the transmission off and check the drive plate.
So the new mounts did make a dramatic difference, but I know several 1404 owners who say the idle is rough, and the builder who made 40 of my model of boat, most with the 1404, told me 10 years ago that this engine does not idle well.
Apart from this it is a great engine, easy to service, always starts immediately, avg. consumption is about 1.5L/hr
Hope that’s of some use.
Dave.

[daveNZ]

I’d still love to hear from someone who know how to service the Bosch unit injectors!?

[goboatingnow]

Originally Posted by daveNZ

I’d still love to hear from someone who know how to service the Bosch unit injectors!?

Most car injector shops can easily handle unit injectors. Common these days.

[Guillaum22]

Hello Dave and please do not appologize for the delay !
Thanks a lot for your message that seems to confirm that the replacement of the engine mount is the first action to try. Could you confirm that you installed the Trelleborg Cushfloat 17-1600-45 please ? And could you let me know if there were an additional issue with gasoil flow or the injectors ?
Thanks a lot Dave again for your great help.
Best wishes
Guillaume

[wingssail]

Well I met some Solomon Islanders who were operating a trading vessel with a Lombardini diesel from the 1940's I think. The engineer showed me his engine room. The engine was clean and purred like a kitten. He had a manual about 4 inches thick and a box full of spares and could still get parts for it (with some delay) and seemed to do OK with it.

[skipperpete]

Originally Posted by daveNZ

I’d still love to hear from someone who know how to service the Bosch unit injectors!?

Hi daveNZ, I just read your thread and the responses from the beginning and I can’t add much to the conversation that you haven’t already covered. I encountered these little engines just before you originally started the thread , first in the Volpi compact gensets and later as a propulsion engine and had very little success with solving the numerous problems with that cursed fuel system. We actually started to send em back to Italy and one came back with a brand new engine instead of the 50 hrs original. Lombardini really went all out to make this a user unfriendly line of engines (FOCS) with the fuel system being just part of the complexity. The head bolts are only good for a couple of tightens, 3 different thicknesses of head gaskets for the same engine, a timing belt that needs to be replaced after any removal ( or 2,500 hrs?).
I agree with your earlier theory about cylinder imbalance across the individual unit injectors and unlike an inline injector pump, the Lombardini requires you to both phase AND calibrate the 4 pumps in situ using special tools ....and skills that take more than a week to acquire. AND there are 3 distinctly different models of the unit injector for the same model engine.
We all got familiar with adjusting unit injectors on Detroit diesels for phase and cal no problem at all ....and VP 2003 injector pumps and Lister pumps but the Bosch unit injectors were a whole new level.
I believe that since Kohler bought out Lombardini the LDW is now common rail so perhaps the idle will smooth out ..Oh, consider the remote possibility that the initial reason for the frantic idling might be that your engine has a constant speed governor not a limiting speed one. These engines were originally for generators and hydraulic pump type industrial applications and may lack the lightweight spring linkages that allows delicate control at low rpm.

[skipperpete]

Do you need a copy of the service manual, it has a fairly good description of setting up the pumps.

[daveNZ]

Guillaume,
Correct engine mounts model. That is the softer of two that fit weight/frequency. Would you like the brochure with graph?

I’ve done nothing with regards to fuel or injectors.
At 1300hrs I’ve been recommended to check the injectors, it’s just the tools to rebalance fuel flow that are needed, so assume it’s not a DIY job!
Dave

[daveNZ]

Pete,
Thanks for the long response. That’s the most coherent and insightful thing I’ve heard and all makes sense. Thank you.
A highly regarded young engineer has unfortunately left the dealer here. I need to track him down!
Dave

[daveNZ]

Originally Posted by skipperpete

Do you need a copy of the service manual, it has a fairly good description of setting up the pumps.

Thanks, I do have the service manual. Re injectors it mentions static advance, and fuel balancing, and I’m sure there is more to refitting them, but I’ve always thought they were best left to the dealer! (So long as they still have engineers trained specifically on FOCS series injectors!)

Is TDC critical for doing rocker clearance? I think the TDC marks are covered.

Cheers,
Dave

[skipperpete]

Originally Posted by daveNZ

Thanks, I do have the service manual. Re injectors it mentions static advance, and fuel balancing, and I’m sure there is more to refitting them, but I’ve always thought they were best left to the dealer! (So long as they still have engineers trained specifically on FOCS series injectors!)



Is TDC critical for doing rocker clearance? I think the TDC marks are covered.



Cheers,

Dave

I’d wager that even the dealer lacks the special tools and fixtures required to adjust the unit injectors. Maybe a fuel injection tech, they do the phase and cal on a daily/hourly basis.
The fuel balancing translates from Italian to “calibration” which is the actual amount of fuel delivered by each pump ( on a test bench this is measured by using a set of calibrated injectors over 100 to 1,000 shots into a set of glass test tubes) and it MUST be identical across the rpm range.

The static advance you mentioned is “Phasing” and relates to the timing marks on the pulley. It’s the precise point of injection relative to crankshaft rotation ( or piston height in some engines) and each injector is a static spill timing procedure. Unlike the calibration which on the FOCS must be done with the engine running, “dynamic cal”...... the static timing is done with a dial indicator and a spill tube with the engine stopped. but this is a different procedure for each of the 3 models of injector across the same engine type.
It just never gets easy with Lombardini, even the dynamic test requires the oil gallery to be plugged because the valve cover is part of the lube oil circuit.
No wonder the damned things shake so much, it’s really really hard to get those 4 injectors to all deliver exactly the same amount of fuel at exactly the right moment. Changing the engine mounts is patching a symptom not curing the source.