Pulling Injectors on a Lehman120

Has anyone ever pulled their injectors? Any issues to consider? Do you need the special tool? I'm thinking about servicing mine before headed south in a month.

When mine were pulled a couple years back (I assisted a mechanic because the Lehman was new to me)..

No special tools..there are crush washers used under the return line banjo bolts so get those from someplace...sorry I don't have a size so for a reasonable price American Diesel isn't ripping you off and saves the searching.

I asked in another thread but didn't get a reply....when we did it, the mech thought we had to and removed the rocker arm. I thought that was crazy but to get to the injectors he saw it as they way...maybe that's where a special tool comes in...but it can be done without one. After removing and replacing the rocker arm, we adjusted the valves to a Lehman 135 specs due to a mixup from the previous owner telling me that's what the engine was.

It ran fine from Ft Lauderdale to NJ and for a year till when ordering parts from American Diesel they started to wonder and a reference to some other part numbers and they convinced themselves and me that I really had a 120. So in talking to them...they say it was probably OK that I had used the 135 valve clearances than had it been a 135 and used 120 valve clearances...I redid the clearances...pretty easy/simple job...but being a single I have plenty of room to work.

I have to do this to my twins. Can you post pictures and a how to? I'd appreciate it. I have lots of tools and I bought a socket for the crank nut to turn the engine over. Just haven't had the urge to "get 'er done".

Its easy, Stretch, no special tools, don't take off the rocker arms, you can anneal the copper washers and re-use them. Take the injectors to a farm shop, same injectors as used on some combines and tractors; don't take them to a "marine" specialist and pay double. Good time to check the cyl head torque and re-set the valves (if memory serves the engine has to be operating temperature?). If you haven't done this for a while the rubber seals on the side of the head might be stiff or brittle, but they should be easy to replace if they are. They don't have to be too tight.
When I put my new injectors in, I didn't need to bleed them, the old dear just started right up. i did undo each injector in sequence to make sure they were all working (I did find one injector that was dead after servicing!) and then I put the valve cover back. She's even noisier with the valve cover off, don't forget ear protection and some sort of goggles for the oil.
Be very gentle with the fuel pipes as they are expensive and a bit rare.

THANK YOU!! Just a shout out to you.

I'll tackle this in the winter months after my deck replacement.

XsBank do you have a 120 lehman ?



Mike

I did, I had to sell my lovely GB32 because I had to move for a job and now I'm back on the Wet Coast and I'm looking for her replacement. Not necessarily a GB.

XsBank thanks for the tip about the injectors found at farm equipment stores. I'll check then out.

Mike

Much easier to pull the injectors if you unbolt the entire rocker shaft and get it out of the way.
American Diesel has all the parts including copper injector seals, copper fuel return line (leak-off) seals, and rubber injector seals. They can provide exchange injectors so you can pull the old ones, install the new ones with all new seals, and just send the removed injectors back.
Yes, you can anneal the copper seals but I don't think it's worth it.
Yes, I have pulled the injectors. Not a bad job, no special tools except a torque wrench. Give yourself a day for the first engine.
After you reinstall the rocker shaft do a cold valve adjustment, then start the engine, warm it up and do a warm valve adjustment.
PM me with a phone or email if you have questions.

av8r said:

Much easier to pull the injectors if you unbolt the entire rocker shaft and get it out of the way.
American Diesel has all the parts including copper injector seals, copper fuel return line (leak-off) seals, and rubber injector seals. They can provide exchange injectors so you can pull the old ones, install the new ones with all new seals, and just send the removed injectors back.
Yes, you can anneal the copper seals but I don't think it's worth it.
Yes, I have pulled the injectors. Not a bad job, no special tools except a torque wrench. Give yourself a day for the first engine.
After you reinstall the rocker shaft do a cold valve adjustment, then start the engine, warm it up and do a warm valve adjustment.
PM me with a phone or email if you have questions.

Click to expand...

Do you know the torque specifications for a Ford Lehman? I can probably look them up somewhere, but curious.

still wondering why some remove the rocker assembly and some don't...

Ben

psneeld said:

still wondering why some remove the rocker assembly and some don't...

Click to expand...

It takes only a few minutes to unbolt and remove the rocker shaft. Then you have easy access to the leak-off tube bolts, it is easy to remove the leak-off tube itself, and then you have wide-open access to the injector bolts and injectors for removal and reinstallation.
After reinstalling the injectors and leak-off tube it only takes a few minutes more to reinstall the rocker shaft, and if it's time to do injectors it is also probably time to do a valve adjust anyway.

av8r said:

It takes only a few minutes to unbolt and remove the rocker shaft. Then you have easy access to the leak-off tube bolts, it is easy to remove the leak-off tube itself, and then you have wide-open access to the injector bolts and injectors for removal and reinstallation.
After reinstalling the injectors and leak-off tube it only takes a few minutes more to reinstall the rocker shaft, and if it's time to do injectors it is also probably time to do a valve adjust anyway.

Click to expand...

the time I needed a mech to help...that's what he suggested/did...just not sure why it was recommended "don't remove all that"...

av8r said:

Ben

Click to expand...

Excellent. Thank you.

I'm having trouble getting fuel past the first injector line on my ford lehman. Their twins same problem. I just replaced the injectors.

Do the return lines have to be torque to certain spec? I cant get fuel past the first Injector line on the injection pump. Thanks

Are you using the lift pump or cranking the engine?
The torque specs are listed above in an earlier post.

Xsbank said:

Its easy, Stretch, no special tools, don't take off the rocker arms, you can anneal the copper washers and re-use them. Take the injectors to a farm shop, same injectors as used on some combines and tractors; don't take them to a "marine" specialist and pay double. Good time to check the cyl head torque and re-set the valves (if memory serves the engine has to be operating temperature?). If you haven't done this for a while the rubber seals on the side of the head might be stiff or brittle, but they should be easy to replace if they are. They don't have to be too tight.
When I put my new injectors in, I didn't need to bleed them, the old dear just started right up. i did undo each injector in sequence to make sure they were all working (I did find one injector that was dead after servicing!) and then I put the valve cover back. She's even noisier with the valve cover off, don't forget ear protection and some sort of goggles for the oil.
Be very gentle with the fuel pipes as they are expensive and a bit rare.

Click to expand...

The fuel pipes are easily obtained from American Diesel.

psneeld said:

still wondering why some remove the rocker assembly and some don't...

Click to expand...

I've just R&R'ed my injectors for the first time. I chose not to remove the rockers, and if or when I need to pull them again, I think I'll go the rocker removal route.

With the rockers in place, I found the hardest part of the process to be during the reinstallation: getting the bleed off screws with the twin copper seals started, without dropping a seal and having to fish it out to try again.

I'd also recommend getting some rubber stoppers to place in the head to fill the holes as your remove the injectors, I think size #5 would work nicely. The thing is, once you have one out, and start removing the bleed off screw from the next one, those little copper seals have an uncanny way of finding that hole! Fortunately they're just large enough to not fall through the nozzle hole!

I imagine somebody with smaller hands and thinner fingers would have an easier time of doing this job with the rockers in place.