Lehman injector pump rebuild

Hi All,


I may have mentioned that after we got our good ship home (4 hour trip), I was doing my first oil service on the Lehman 120 and I had NO oil in the injection pump. I serviced it and all has been OK since. How long did it have no oil? I have no idea. I imagine when an injector pump fails, the motor just stops.


I'm guessing the pump is probably full of little pieces, but going to ask anyway. Have any of you every rebuilt an injection pump? The cost for a trade in on a rebuilt at my favorite marine supply store is $1000 + tax.


Just pondering the "what if" question.


Dave

If it had no oil in it, it is probably on it’s way out now. I would not trust it or at least get an unlimited towing policy... The 120 are supposed to have the oil changed every 50 hours since the oil gets diluted with diesel. So you probably have had some lubrication going on with the diesel but the question is how much. That is an unknown. As you get to know your engine you may be able to increase the 50 hours depending on how diluted the oil gets in the 50 hours or not. Bob Smith said to start out at 50 and watch how diluted the oil is and maybe increase the hours a bit at a time. One guy in my class said one of his 120s needed it at 50 hours and the other could go 100.

One TFer supposedly ran his pump with no oil for many hours .... Maybe multiple day runs?


and never had further issues with if for years if I remember correctly.


I would bdconsrtvative also and have it rebuilt....or replaced.... That $1000 exchange actually sounds pretty good.


Where was it please? May be in my future too.

Sheaf Diesel Service in England advertises reconditioned Ford Lehman Marine Injection Pumps for $695 US plus $94 shipping both ways on eBay. Around $900 total.

They will require the old pump be sent to the.

I know of one person who did two pumps through Sheaf Diesel and was very satisfied. Quotes for similar service in Seattle was around $1,600 each

Where was it please? May be in my future too.[/QUOTE]


Harbor Marine, Everett, WA

Dave_E said:

Where was it please? May be in my future too.

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Harbor Marine, Everett, WA[/QUOTE]

Sheafs advertising is on eBay. Type in Ford Lehman injection pump.

There is also a remanufactured injection pump listed for $2100 by a seller.

psneeld said:

One TFer supposedly ran his pump with no oil for many hours .... Maybe multiple day runs?


and never had further issues with if for years if I remember correctly.


I would bdconsrtvative also and have it rebuilt....or replaced.... That $1000 exchange actually sounds pretty good.


Where was it please? May be in my future too.

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I did just that when a brass nipple (should have used steel) I inserted in an elbow to the drain broke from vibration. I ran (I think) for about 10 hours with no oil. We just completed the Great Loop having cruised 6,500 miles on that same pump.

Concerning changing the oil every 50 hours, here's another anecdote. A dockmate ran his 120 for THIRTEEN years, probably 1,500 to 2,000 hours, before learning that the oil should be changed. That pump still lives. As for my pump, I will continue to use it until it fails which may not be for a very long time. I will, however, change the oil every 100 hours. Just anither story. Take from it what you wish.

I change mine every 100 hours. That was the recommendation from Bob Smith and Norm Dribble 20 years ago.

And as recommended by them, I sniff the drained oil for a diesel smell and measure the amount

Sandpipers Leman has 6,200 hours on it and the drained oil does not have a strong diesel smell. And has not significantly changed since we bought it in 2000. It is the original pump.

Would an oil analysis set your mind at ease? They could test for wear by the metal levels in the oil.

I got mine rebuilt at Midwest Fuel injection apparently they saw me coming to the tune of 2500 for a rebuild. 500 hours later it started leaking. I bought a socket and kit from France and fixed it myself. I’ll send it off to England next time if needed. The rack was stuck and it would not idle belie 1000 rpm.

If you are do it yourself kind of guy, remove the pump and drive it to Northland Diesel in Bellingham. They work on these all the time. I had one of mine done right after buying the boat and they had it done in one day. Great service. If you need help with doing it, call Steve Smith at Compass Marine in Anacortes.

I'd fill the pump with oil, run it for a good number of hours, and drain the oil out into a paint or coffee filter. See how much metal debris comes out. If none or minimal (all will have a little dust), I'd be tempted to just run it.

I am very familiar with these pumps. They are tough as nails. Removing and replacing them is a P.I.A. but can be done if you have some mechanical skills. My first reaction is to advise you to "just run it" if the engine runs well, not a lot of smoke and idles well just go for it! For sure do an oil analysis, it will give you an idea what is going on inside. If you are anxious to get your hands dirty pull an injector and do a "pop" test with your pump. It will confirm what you already know from listening to your engine. If it runs well, the injectors will probably "pop" well. Pulling one or more injectors can also be a PIA because the return line must be removed and the injectors don't like to come out easily, but again, it can be done.

Fuel oil is a pretty good lubricant and I suspect you did no real harm by running it without it's own source of oil.

pete

Dave_E said:

Hi All,


I may have mentioned that after we got our good ship home (4 hour trip), I was doing my first oil service on the Lehman 120 and I had NO oil in the injection pump. I serviced it and all has been OK since. How long did it have no oil? I have no idea. I imagine when an injector pump fails, the motor just stops.


I'm guessing the pump is probably full of little pieces, but going to ask anyway. Have any of you every rebuilt an injection pump? The cost for a trade in on a rebuilt at my favorite marine supply store is $1000 + tax.


Just pondering the "what if" question.


Dave

Click to expand...

I tried a DIY injection pump rebuild once when I was an auto tech. I eventually took it to a diesel shop. They had it done in just a couple hours. I watched and learned. There are some special tools involved that I didn't have and knowledge to boot. Setting it up on the engine was the easy part. Before you remove it, clean the area very good. Make note of any alignment marks so you reinstall it in the same orientation. Most injection pumps are timed by rotating them. So they need to go right back in the spot where they came out. It may be a good idea to get a mechanic to double-check the timing. It could be off slightly. You will save some money by removing the pump yourself and taking it in to be rebuilt. I would use a local agricultural diesel shop for the repair/rebuild. They will be cheaper than a marine outfit. You could let a marine diesel tech reinstall it and set the timing. Another thing to mention is the injectors, I would take them out and take them in to be serviced. I would pay to have them balanced. When all of the injectors "pop" at the same pressure the engine will run smoother and quieter.

Ford Lehman Marine Diesel engine stuff

This links to a really cool Old World website with related information. I spent way too much time there. I never heard of a Fifie, or Advocaat before. Took me back to the days of catching fish and at the same time watching out for marauding Vikings.

Not sure you need to worry about it too much if the engine runs good. I bought my boat in New York and sailed it to Montreal (a 10 day trip, doing 8-10 hours a day). A few weeks after arriving I started doing the suggested maintenance. There was no oil in the injection pump and I eventually found the drain plug in the bilge. From the looks of it, it had been there for a while. I put the plug back, put some oil in the pump and I've been changing the oil once or twice a season since then. That was 10 years ago.

Thank you all for the replies. Good information. We’re currently on a 10 day trip in the San Juan’s and she purrs. Using 2.5 gallons an hour average (1800 RPM), and the head gasket is leaking oil and water (small amounts), but that’s for a different thread. ?

Fuel in Lube Oil Reservoir ('78 120 Lehman)

Hi, I realized I had a problem with the Injector Pump when I started noticing fuel in my drip pan. It was coming out of the bypass hose for the Injection Pump. When I drained the Lube Oil Reservoir it was only Fuel...no Oil. I re-filled it with Lube Oil and ran the engine for several hours and re-checked it again. Only fuel came out.
I presume the Injection Pump seal(s) is leaking and causing this bypass drainage and oil replacement by fuel. What I am reading in the forum is that apparently the fuel oil is enough to keep the pump happy and to simply leave it alone because others have run this way for years. (However, I haven't seen this particular issue show up in this writing...)
I have placed a container under the Injection Pump By-pass hose in my engine pan in the meantime...(the engine is running smoothly).
Comments?

Pugetrawler said:

Hi, I realized I had a problem with the Injector Pump when I started noticing fuel in my drip pan. It was coming out of the bypass hose for the Injection Pump. When I drained the Lube Oil Reservoir it was only Fuel...no Oil. I re-filled it with Lube Oil and ran the engine for several hours and re-checked it again. Only fuel came out.
I presume the Injection Pump seal(s) is leaking and causing this bypass drainage and oil replacement by fuel. What I am reading in the forum is that apparently the fuel oil is enough to keep the pump happy and to simply leave it alone because others have run this way for years. (However, I haven't seen this particular issue show up in this writing...)
I have placed a container under the Injection Pump By-pass hose in my engine pan in the meantime...(the engine is running smoothly).
Comments?

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Injection pump is an extremely high pressure pump. Fuel may allow it to run on for a while but eventually the pump is going to eat itself beyond repair.

I took Bob Smiths last Lehman seminar. He talked about the oil in the 120 injection pump and how it gets diluted with diesel. His opinion was that this was a critical issue and should not be overlooked. I would fix it asap. Some will say it is ok, but Bob did not. Now who are you going to listen to?

thanks

Thanks for you quick reply. I am planning to have the pump checked out ASAP. You have both verified what I suspected.

Cheers from Vashon

Comodave said:

I took Bob Smiths last Lehman seminar. He talked about the oil in the 120 injection pump and how it gets diluted with diesel. His opinion was that this was a critical issue and should not be overlooked. I would fix it asap. Some will say it is ok, but Bob did not. Now who are you going to listen to?

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A friend is still running his Lehman 120 after finding out eight years ago that the injection pump oil should be changed. Before that he ran it for THIRTEEN years and probably 2,000 hours without changing the oil. When he did it was very diesely. That pump is still running that 120 today. I don't know what to conclude from this except maybe these pumps are more robust than most think. Maybe it's also why Bob Smith updated his oil change recommendation from 50 to 150 hours. Perhaps no one has ever tested how long a pump can go without an oil change so no one one really knows what the best interval ought to be, hence, change it often.

Fortunately my engines don’t have the same system as the 120 so I don’t have a separate oil to change. However if I had a 120 I would change the oil. Just because someone got away without oil or changing the oil does not mean that it will work for everyone. Do you run your engine without oil or diluted oil, of course not. So why would anyone do that to an expensive injection pump. There is a signature on this site something like; There is the right way, the wrong way and the way someone said they got away with... Getting away with it does not make it right. And Bob did say that 50 hours was the recommended starting point and that any given engine might be able to go longer. He said this at his last seminar shortly before he died, so I will take it as his last opinion.

This is what I have heard through the years....


Bob also has said the 50 hrs was simpler than trying to figure out if you DID have dilution.


Bob also said that a new injection pump probably could go longer but the trick was to figure out when the dilution started and start decreasing change interval.


He also changed his mind on more than a few things through the years and now his son has changed a few more.


Bomac who knows a thing or two about Lehman's has some different thoughts too from Bob's.


It's OK to understand why an expert might say one thing knowing most owners aren't mechanically inclined or given to analytical thought and think beyond that.

I wasn't suggesting not to change the oil. I change mine at 100 hours. The anecdote I related was to illustrate that these pumps, apparently, can take a lot of abuse. Some boaters might be frightened into an expensive repair unnecessarily just because their oil hadn't been changed out for a long time or it was run dry. Change the oil at 50, 100, 150 hours, whatever you feel comfortable with and run the pump until it dies. Methinks that will be a long time coming but with boats one never knows. Injector pumps generally don't just stop one day. There will be warning signs.

Comodave said:

Fortunately my engines don’t have the same system as the 120 so I don’t have a separate oil to change. However if I had a 120 I would change the oil. Just because someone got away without oil or changing the oil does not mean that it will work for everyone. Do you run your engine without oil or diluted oil, of course not. So why would anyone do that to an expensive injection pump. There is a signature on this site something like; There is the right way, the wrong way and the way someone said they got away with... Getting away with it does not make it right. And Bob did say that 50 hours was the recommended starting point and that any given engine might be able to go longer. He said this at his last seminar shortly before he died, so I will take it as his last opinion.

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