LEHMAN 120 Beginner Questions

I'm on the learning curve with my 2 Lehman 120s in recently purchased GB42. I know about Racor filters, fuel lift pumps and how to change oil/filters in my engines. I also got copy of Operation Manual from the GB Forum site. I wanted to attend next month's Lehman workshop in Lake Park but class is full. So, here are a few questions (4) that I have:
1. Frequency for changing transmission oil?
2. Is it important to have temp sensor or gauge for transmission?
3. Is it crucial to check torque of head bolts every 400 hrs for normally aspirated Lehmans or just turbo charged?
4. My next maintenance step is changing oil in Simms injector pump reservoir. I've already seen some great posts on this. I understand where the drain plug is, where the "fill level" plug is on right side facing sump, but is the actual "fill plug" on top, the very first plug forward of injector lines? Mine is circular with a slothead. Just after is another plug-looking with a white cylindrical extended plastic cap with a tip projection.

simms pump

Yes, the fill hole is the one with the slot.

Dan

thanks Dan and others for speedy replies!

manuals

The GrandBanksOwners.com forum has a full set of manuals for your boat and engines.

Dan

JESSEDIVER49 said:

I'm on the learning curve with my 2 Lehman 120s in recently purchased GB42. I know about Racor filters, fuel lift pumps and how to change oil/filters in my engines. I also got copy of Operation Manual from the GB Forum site. I wanted to attend next month's Lehman workshop in Lake Park but class is full. So, here are a few questions (4) that I have:
1. Frequency for changing transmission oil? whenever you want....some like yearly some maybe every 5....I go with the every 3 years, or 500 hours concept
2. Is it important to have temp sensor or gauge for transmission? no but nice
3. Is it crucial to check torque of head bolts every 400 hrs for normally aspirated Lehmans or just turbo charged? split debate..some of us think that is way too often and you risk bigger problems...better to wait till 1000 and just pull the head and do all other associated maintenance at this interval...injectors, cheak head and cylinders, etc....
4. My next maintenance step is changing oil in Simms injector pump reservoir. I've already seen some great posts on this. I understand where the drain plug is, where the "fill level" plug is on right side facing sump, but is the actual "fill plug" on top, the very first plug forward of injector lines? Mine is circular with a slothead. Just after is another plug-looking with a white cylindrical extended plastic cap with a tip projection. it's the slotted round or in my case hexagonal one....

Click to expand...

good luck!

Just a note on the Simms pump - make sure you can get the filler open before you drain it. The case is very soft, do not over torque the drains. I would not even take out the level plug, just measure the quantity of oil you need. You can get an adapter for the drain to take an ice maker valve; that saves the opening and closing. Catch the oil with a ziplock. There are other "hacks" too, when you have the time...

It's 14oz to fill the Simms

120 Ford Lehman Simms Maintenance

Again,
thanks for all the good info on the Simms. My boat is a 1984. Today I started the Simms maintenance process - had no problem unscrewing the fill hole on top but when I tried to unscrew the 13mm bolts on bottom drain and on side overflow, using a socketed wrench with a 5-6 " handle, each bolt was too tight to loosen. Before using a wrench with longer handle and better leverage and risk "ringing off" the head of a bolt, I thought I'd check this out with all the experts to see if there is something else I should do before applying more muscle to loosening these bolts. Same situation for both engines. Fill screw on each loosen with no problem. Others are super tight. Also, previously I've had to loosen fuel bleeder bolts to prime injectors and purge out air bubbles and I used same 13mm socketed wrench to loosen and re-tighten with no problem.

simms pump

should be a 1/2 in wrench.

Dan

13mm = 1/2"

SIMMS ON LEHMAN 120s

JESSEDIVER49 said:

Again,
thanks for all the good info on the Simms. My boat is a 1984. Today I started the Simms maintenance process - had no problem unscrewing the fill hole on top but when I tried to unscrew the 13mm bolts on bottom drain and on side overflow, using a socketed wrench with a 5-6 " handle, each bolt was too tight to loosen. Before using a wrench with longer handle and better leverage and risk "ringing off" the head of a bolt, I thought I'd check this out with all the experts to see if there is something else I should do before applying more muscle to loosening these bolts. Same situation for both engines. Fill screw on each loosen with no problem. Others are super tight. Also, previously I've had to loosen fuel bleeder bolts to prime injectors and purge out air bubbles and I used same 13mm socketed wrench to loosen and re-tighten with no problem.

Click to expand...

Update: I was able to free up the plugs using PB Blaster. Great product and recommendation! I also took advice to use a torque wrench to limit amount of torque on loosening. Plugs broke loose at less than 30 ft-lb.

Here is some excellent advice for you Lehman owners, stolen shamelessly from the GB site:
Sure Fred, just put an M8-1 to 1/8 pipe fitting in the bottom in place of the drain plug. Then put a 90 degree ice maker needle valve in the fitting with a 12" piece of ice maker tubing on it.

When ready to change the oil in the pump and with the engine hot, put the tubing end in a catch container, I use an old 1 qt. oil bottle, open the valve and the oil drains right into the bottle. Take the fill cap out to aid in oil flow.

Tighten the valve back closed, refill with oil, either a measured amount or to the bottom of the level hole and you're ready to go, no muss, no fuss.

This plan also works with pumps that have partially stripped threads as the fitting can be JB Welded into the hole, epoxied into the hole, or permatexed into the hole as fits your particular situation. Since it never again needs to come out it can be a permanent fix.

Now the bad part. Nobody makes an M8-1 to 1/8 pipe fitting. At least I've never been able to find one. So, I make them on my home hobby lathe. There have been about 30 put into use in the last 4 years that I know about with no complaints yet.

Ken

Drain valve 002.JPG
Description:
Filesize: 1.56 MB
Viewed: 3 Time(s)

Now the bad part. Nobody makes an M8-1 to 1/8 pipe fitting. At least I've never been able to find one. So, I make them on my home hobby lathe. There have been about 30 put into use in the last 4 years that I know about with no complaints yet.

Click to expand...

McMaster-Carr lists one.

120HP Lehman runs rough below 1000RPM

I recently purchased a 38' Permaglas trawler that has a 120HP Lehman and the engine runs rough below 1000 rpm. Would it cause a problem to run the engine for long periods of time below 1000 rpm or is there a solution to make it run smoother. Would like to be able to troll for salmon! Thanks.

psneeld wrote;

"split debate..some of us think that is way too often and you risk bigger problems...better to wait till 1000 and just pull the head and do all other associated maintenance at this interval...injectors, cheak head and cylinders, etc...."

If I was buying a new engine and the sales guy said it may be a good idea to R7R the head at 1000hrs I'd walk right out.

I've got about 1000hrs on my 10 yr old Mitsu and I'm not EVEN thinking of pulling the head.

By the way w your experience what bad things can happen while re torquing head studs. All I can think of is stuck nuts that try to turn the stud instead of the nut. And the clamping force won't be the same as the nut w different threads. Are the threads designed to compensate for this?

I'd do a lot of things differently if I knew the history of an engine...not all of us have that luxury.

Xsbank said:

Here is some excellent advice for you Lehman owners, stolen shamelessly from the GB site: Sure Fred, just put an M8-1 to 1/8 pipe fitting in the bottom in place of the drain plug. Then put a 90 degree ice maker needle valve in the fitting with a 12" piece of ice maker tubing on it. When ready to change the oil in the pump and with the engine hot, put the tubing end in a catch container, I use an old 1 qt. oil bottle, open the valve and the oil drains right into the bottle. Take the fill cap out to aid in oil flow. Tighten the valve back closed, refill with oil, either a measured amount or to the bottom of the level hole and you're ready to go, no muss, no fuss. This plan also works with pumps that have partially stripped threads as the fitting can be JB Welded into the hole, epoxied into the hole, or permatexed into the hole as fits your particular situation. Since it never again needs to come out it can be a permanent fix. Now the bad part. Nobody makes an M8-1 to 1/8 pipe fitting. At least I've never been able to find one. So, I make them on my home hobby lathe. There have been about 30 put into use in the last 4 years that I know about with no complaints yet. Ken Drain valve 002.JPG Description: Filesize: 1.56 MB Viewed: 3 Time(s)

Click to expand...

This is what I was trying to find out about. Do you know this person Ken or how I can find out? New to this and really not sure yet.

Thanks Gary!

jleonard said:

McMaster-Carr lists one.

Click to expand...

Are you still making these for customers? I could use two for my engines if you do?

Thanks,

Gary

Jessediver,

I just finished putting the drains in my Simms injector pump. I tapped the drain with NpT thread and put in the simple drain valve. Enclosed in a photo of my new easy drains. We have twins and this makes our Starboard SIMM pump so much easier to service. Careful tapping of the aluminum housing and several flushes to insure no filings in the pump and it was a fairly simple job. It took about 1 1/2 hours to do the work.

I bought a valve frpm Ken but i don't recall his address. Search the gb site. I used jb weld. Works great as i am on the loop so the hours are adding up.

meridian said:

I bought a valve frpm Ken but i don't recall his address. Search the gb site. I used jb weld. Works great as i am on the loop so the hours are adding up.

Click to expand...

Is there some trick to get JB Weld to work for this? Have tried sealing slow drip fuel fittings with it - no luck. Nervous about doing this on the Simms pump.

I've been using the black 2 part stuff. Are you putting it on the threads and then globbing it around the base of the fitting? How are you cleaning the threads first?

I've pretty much accepted the 1/2 oz per week leak, but would love to solve this problem once and for all. This is the second FL 120 I've owned and they both had stripped drain plugs that leaked a little.

SeaMoose,

I have not used JB Weld on ours, after retreading to NPT thread I applied Locktite 242 and have zero leakage. I would encourage you to consider tapping the drain and flushing the pump and getting a secure fit.

A little confused why use an M8-1 to 1/8" pipe thread? The drain plugs aren't metric?

I honestly do not know why. I was following the advice of my mechanic.

My injector pumps are self lubricating. It was done by Paul Meyer of PM Diesel in Steveston, Richmond, B.C. Next time I am on the boat I will see if I can take a picture of the lubrication hose assembly he used to lubricate the pump.

Grahamdougladd,

That sounds very interesting. How long ago did you have that done, how many hours? I believe the Lehman 135's are self lubricating and have wondered if a retro fit would allow the 120's to be as well. Looking forward to the pics.

The problem with the Simms pump is it leaks diesel into its lube oil. At oil change intervals (50 hours) you will find more liquid in the reservoir (if you have removed and capped the messy vent line) than you put in. If you have the stock, messy vent system, that fluid will be in the bilge or catch bottle. If you have plumbed the Simms into the engine lube system, a logical way to beat the 50 hour service interval, you are diluting your oil with diesel. This leads to reduced oil performance, too much fluid in the sump which can lead to failed seals and if you get enough diesel in there, possible uncontained runaway. On later versions of the engine, Ford plumbed the injector pump, but it's not a Simms.

I forgot to add that the injection pump is very intolerable to contamination - using engine oil can damage the pump unless the oil came straight out of the filter.

Plumbing the Simms pump is a bad idea.

However, you can make your life better by removing the drain line and capping it. If not already there, drill a small hole in the bottom of the slot in the filler cap for venting. Replace the drain plug with a valve. For the level plug, either glue it shut or never remove it, just measure the oil quantity you put in. Finally, drain the oil into a ziplock bag, it will fit around the pump and you don't have to fuss with a container.

Greetings,
Mr. X. I agree. Simms pumps WILL leak diesel into it's own lube oil IF WORN. On a previous Leh' I've experienced fuel contaminated lube oil but on the current 2 Leh's, no such experience. The way I check is a smell test AND removal of the level plug before I drain the lube oil. Any initial flow out of the level plug denotes diesel dilution of the lube oil. Just the way I do it.

Hey RT, life's too short to write a disclaimer on every entry. If you are happy with your own process, go crazy. I believe that all Simms pumps leak internally and Ford knew this, otherwise why the drain pipe? Obviously you have taken yours off, which saves a lot of mess. If you have not plumbed your Simms as per the previous post, the contamination cannot be from the Simms, it is from the injectors, either a loose high pressure fitting or a loose return line, not the Simms.

Isn't Simms part of Lucas? When I owned a TR4 back in the mists of time, we used to say "give an Englishman a piece of tin and a hammer and he will do something silly with it." My grandfather was a Brit engineer and he invented the Anderson shelter... Just added that so that no Brits will take me seriously.

The self lubrication system was done by the previous owner and I really have not given it much thought. I will take a close look at it next time I am on the boat. It does leak a little oil though and I have been thinking about replacing a hose and fitting.