Ford Lehman 135hp leaking around injector seal

[Mobcat]

Hi all have 2 of my rear injectors leaking around what I think is a seal to the block for diesel delivery to injector under the valve cover, I think it’s oil weeping out but maybe it’s diesel, it’s only a slight leak when engine is running but it’s annoying, any ideas on a fix for it ? I will post a video to get the gist of it.
Thanks in advance
Michael

 

[syjos]

Hi all have 2 of my rear injectors leaking around what I think is a seal to the block for diesel delivery to injector under the valve cover, I think it’s oil weeping out but maybe it’s diesel, it’s only a slight leak when engine is running but it’s annoying, any ideas on a fix for it ? I will post a video to get the gist of it.
Thanks in advance
Michael

Loosen the nuts 1/8 turn then tighten the nuts.

If that doesn't stop the leak, apply thread sealant to the threads.

 

[Mobcat]

Hi Stylos, I’m thinking the big nut obviously squash’s a grommet type rubber collar or something to stop the oil leaking out of the head, do you just tighten the big nut till it stops leaking oil, has your motor leaked in the same place ?

 

[av8r]

The large nut compresses a rubber seal between the head and a cup washer. It is the oil seal and can be tightened as necessary. The small nut connects to the adapter that connects to the injector. You can loosen the small nut, tighten the adapter, then tighten the small nut, torq specs are in the manual.
If it is an oil leak the large seal under the big nut might need to be replaced by disconnecting the small nut, removing the large nut and simply relacing the seal, they are cheap and easy to do.
Make sure the rocker cover gasket is good and the screws are snug, then snug up the large seal nut and see what happens.

 

[syjos]

Hi Stylos, I’m thinking the big nut obviously squash’s a grommet type rubber collar or something to stop the oil leaking out of the head, do you just tighten the big nut till it stops leaking oil, has your motor leaked in the same place ?

From looking at the video, it's diesel leaking, not oil. Unless you just changed oil, the leaking fluid is too clean.

Tighten the first small nut for diesel leak and the big one for oil.

The rubber grommet does get hard as it ages, sometimes preventing it from sealing properly. I replace those grommets and valve stem seals, which also leak when hard from age, every 2,000 hours.

 

[Wester Lee]

‘Em l missing something? If it was diesel wouldn’t it be red in color. I would confirm no leak @ the valve cover first.

 

[syjos]

‘Em l missing something? If it was diesel wouldn’t it be red in color. I would confirm no leak @ the valve cover first.

OP is in Australia, I think they dye blue, green, brown? I think.

If the leaking liquid is oil, shouldn't it be blackish?

 

[Mobcat]

Hi Syjos yeah it’s new oil first day thus it’s clarity, I am thinking it’s definitely oil, I’m just going over a few things prior to a large trip up the East Coast, it’s always nice heading off with a zero drip status, it’s hard with a Lehman to achieve but possible I believe with time spent, I also have a weep on the aft end of the injector again really slight but annoying, I thought it may of been the stud for the compression fitting for the fuel intake but I removed that and put thread sealant on it but it’s still there the weep, I’m thinking it must be weeping from the head gasket of the injector pump the one held done by the Allen key bolts, have you ever seen this problem? Again minor but annoying all the same . I did try tightening up the big nuts on the oil seal today and it definitely helped do you think I should try tightening them more as it definitely slowed the flow to very minimal now or just get new grommets , I will post another video of it.
Thanks for your help to guys

 

[Mobcat]

Hi Wester yeah in Oz our diesel is a yellow colour, should be gold the price it is ATM though $2:40 a litre at River Gate Marina but I do think they are price gouging they always do there that’s why I try to never buy fuel there and the reason I am trying to avoid dripping any away

 

[syjos]

Hi Syjos yeah it’s new oil first day thus it’s clarity, I am thinking it’s definitely oil, I’m just going over a few things prior to a large trip up the East Coast, it’s always nice heading off with a zero drip status, it’s hard with a Lehman to achieve but possible I believe with time spent, I also have a weep on the aft end of the injector again really slight but annoying, I thought it may of been the stud for the compression fitting for the fuel intake but I removed that and put thread sealant on it but it’s still there the weep, I’m thinking it must be weeping from the head gasket of the injector pump the one held done by the Allen key bolts, have you ever seen this problem? Again minor but annoying all the same . I did try tightening up the big nuts on the oil seal today and it definitely helped do you think I should try tightening them more as it definitely slowed the flow to very minimal now or just get new grommets , I will post another video of it.
Thanks for your help to guys

You need to loosen the first small nut on the fuel pipe so that the pipe does not hinder the turning of the oil seal nut. Tighten it last.

I've not seen many injection pumps on Lehmans leak externally. The leaking on old Lehman injection pumps is internal.

 

[Mobcat]

Thanks Syjos I will try the nuts again in that sequence, and with the injector pump I might revisit the stud into the body of the injector pump for the compression union again as when I watched the video on my computer geez it looks like it’s coming out of that connection, things are bad when you can see things better on a computer than in real life hey

 

[Mobcat]

And yes Western that valve cover gasket can be a beach to get that to seal, even with brand new gasket, the only way I could mine to seal 110% was to use a JB weld copper fine bead right around the cover edge put the gasket on the cover let it set up over night and then repeat on the head with a little JB weld copper the next day on the new Allan key headed bolts and washers I used to fasten it down with the old star head valve cover bolts where useless imo about as useless as that cam driven fuel lift pump on the lehmans, throw that in the bin and bring your motor into the 21st century with a 12 volt lift pump makes life a breeze and will see this motor to heaven and cheaper than Noah's diaphragm as well and a million times better for filter changes priming etc, and I agree those valve cover gaskets can be the source of many a oil leak that you don’t think is coming from that area but it is the only way I know mine isn’t leaking anymore is to do the old cigarette paper test all the way around the cover, and you could roll a spliff after doing a lap of mine now days no problem at all she’s not leaking a drop but took some serious effort and about 3 years and 2 gaskets and new fasteners washers to get it right lol

 

[Mobcat]

Well I fixed the leak at the back end of the fuel injector pump, it turned out it was the pulsator diaphragm the round circular thing on the back aft port side of the injector pump, simple fix to it just had to be pinched up a little “tightened “ and it’s fixed and that’s the kind of fix I like zero cost it was weeping from the attachment thread of the pulsator diaphragm and weeping aft and around the injector pump to the same level on the starboard side of the injector pump. Leaks can be Bizzare sometimes especially on lehmans I’m finding over the years, but I haven’t found one yet that has beaten me even the smallest of them, what I have found with leaks on a Lehman always start at the valve cover like Wester Lee said because chances are it will becoming from there even in the most obscure places and amazingly enough they are so hard to find there origin on the valve cover cigarette paper being the answer ….,it’s a good philosophy to keep on top of all weeps and leaks even the smallest because little leaks can turn into big leaks very quickly and can be devastating to a unattended engine on voyage .

 

[syjos]

I use valve cover hold downs on Sandpiper to spread the pressure from the bolts to a wider area. There are many styles to choose from. The hold downs need to be filed or shaped with a grinder to fit on the Lehman valve cover but work well to mitigate leaks.

 

[Mobcat]

That’s a good idea Syjos, I have seen them before but didn’t think of using them, I have ordered some for next time I do my valve clearance checks, I do think that’s the problem with the valve cover over the years they get a bit out of shape and have trouble keeping a even pressure on the head to form the seal.

 

[syjos]

That’s a good idea Syjos, I have seen them before but didn’t think of using them, I have ordered some for next time I do my valve clearance checks, I do think that’s the problem with the valve cover over the years they get a bit out of shape and have trouble keeping a even pressure on the head to form the seal.

The valve cover was bent up around the flange when we bought the boat. It's made of thin stamped sheet metal so will not remain flat. Looked for a cast cover back then without success.

I placed 1/4" steel plates, sized to fit, on either of the flange and applied a bunch of C-clamps to squeeze the flange flat. A little tweaking with a short steel bar and mallet got the cover fairly flat.

Using the hold downs for 22 years, the covers flange is still flat and so far, no leaks.

 

[catalinajack]

Yup, had that problem (distorted surfaces) on our Lehman 120s. I simply hammered them back into good shape but those cork gaskets can be problematical getting them to stay fully on the mating surfaces. Plus, you can't ever be certain that a portion of the gasket hasn't slipped inward. To give myself a better chance of getting a good seal, I ditched those relatively small bolts that hold down the covers. Instead, I inserted mounting studs into the head such that I can just drop the cover down with the gasket already fixed securely in place on the cover. The cover is tightened down instead with oversized nuts and/or washers. It's been three years since I made that retrofit and, in the meantime, I had the covers off to retorque the heads and adjust the valves with no leaks using the same gasket.

In the U.S., those studs can be found at McMaster-Carr. Simple installation. Just clean out the oils from the holes, a bit of brake cleaner and a q-tip, some medium strength Locktite, and double nuts to fix them in place in the head. Remove the double nuts and drop the cover in place. Simple and inexpensive.

 

[Reef Wanderer]

12v Diesel Lift Pump

about as useless as that cam driven fuel lift pump on the lehmans, throw that in the bin and bring your motor into the 21st century with a 12 volt lift pump makes life a breeze and will see this motor to heaven and cheaper than Noah's diaphragm as well and a million times better for filter changes priming/QUOTE]
Interested to know which 12v pump you used on your Lehman motor Mobcat? I recently replaced my mechanical pump with a Facet 60300 12v pump and it only lasted a few hours (about 3 hours)? Facet-Purolator have told me I must have done something wrong on installation!

 

[Mobcat]

Hi RW I would say you definitely must of done something wrong on installation as I have had these on gensets etc do over 10000hrs and never even had a problem, they are so simplistic in there design and basically fail safe, but I suppose you can’t rule out a dud can you ?

 

[Reef Wanderer]

Hi RW I would say you definitely must of done something wrong on installation as I have had these on gensets etc do over 10000hrs and never even had a problem, they are so simplistic in there design and basically fail safe, but I suppose you can’t rule out a dud can you ?

Because I bought the pump more than 12 months ago (but didn't install it until two weeks ago) Facet-Puralator won't honour a warranty. I really don't see what I could do wrong on the installation. It was simply plumbed between the Racor and the on-motor fuel filters. All new high quality fuel hose, it worked straight up and primed the air out without any hiccups. I wired it with a relay to the ignition switch, plus a bypass switch for priming with ignition off. When it stopped I replaced it this week with a cheap 12v "immitation" Facet pump that runs perfectly?
Which pump did you use Mobcat?

 

[Mobcat]

I remember having a cheapie on a forklift and it run for ever, I lashed out and bought a good brand for the boat Facet of memory same on my genset when it died recently I think that was a facet as well because the original Kohler one died at like 400hrs and a new one was like $500 genuine Kohler so I just put a facet in-line for about $50 bucks I suppose …., yours just must of been doji I would say, just buy a new facet keep the receipt and take your doji one back and you will have a spare win win

 

[catalinajack]

Hi Syjos yeah it’s new oil first day thus it’s clarity, I am thinking it’s definitely oil, I’m just going over a few things prior to a large trip up the East Coast, it’s always nice heading off with a zero drip status, it’s hard with a Lehman to achieve but possible I believe with time spent, I also have a weep on the aft end of the injector again really slight but annoying, I thought it may of been the stud for the compression fitting for the fuel intake but I removed that and put thread sealant on it but it’s still there the weep, I’m thinking it must be weeping from the head gasket of the injector pump the one held done by the Allen key bolts, have you ever seen this problem? Again minor but annoying all the same . I did try tightening up the big nuts on the oil seal today and it definitely helped do you think I should try tightening them more as it definitely slowed the flow to very minimal now or just get new grommets , I will post another video of it.
Thanks for your help to guys

Geez, wouldn't a sniff test reveal whether it is lube or diesel oil? Also, if it were diesel fuel, that would mean the steel line is fractured and, if it were, diesel would be shooting a lot more being that the line pressure is in excess of 1,000 PSI. And, it it is diesel, wouldn't that mean fuel dilution of the lube oil? What am I missing?

 

[Mobcat]

Hi CJ that leak has been fixed it turned out to be the Diiaphramic pulsator had to be tightened up a little bit it was weeping out of its connection and tracing around the top of the injector to disguise its origin, as it is as well that little syphon point from the weep on the duapramic pulsator was the cause of my fuel back syphoning to the tank when the boat was left a while and making her lazy to start because of lack of diesel at the injector pump, now she starts instantly like tbh it never has before, not that it was a big problem prior maybe 2 -3 seconds of crank time, but now it’s instant, it’s funny isn’t that the smallest thing can lead to multiple issues, and that’s why it pays to be vigilant with these old girls as most things are a easy fix if dealt with early enough

 

[catalinajack]

Hi CJ that leak has been fixed it turned out to be the Diiaphramic pulsator had to be tightened up a little bit it was weeping out of its connection and tracing around the top of the injector to disguise its origin, as it is as well that little syphon point from the weep on the duapramic pulsator was the cause of my fuel back syphoning to the tank when the boat was left a while and making her lazy to start because of lack of diesel at the injector pump, now she starts instantly like tbh it never has before, not that it was a big problem prior maybe 2 -3 seconds of crank time, but now it’s instant, it’s funny isn’t that the smallest thing can lead to multiple issues, and that’s why it pays to be vigilant with these old girls as most things are a easy fix if dealt with early enough

Diiaphramic pulsator - new one for me. What is it? Where located? What is its purpose?

 

[Tator]

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