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120hp ford lehman questions

scotwagner

New member
"I'm looking at buying a 1

"I'm looking at buying a 1984 Hudson Force 50 sailboat with a 1984 120hp Ford Lehman. She has roughly 3,000 hrs. I'm completely unfamiliar with these engines so ANY input is helpful. Are they a workhorse or a bundle o' problems? It is my understanding they are tractor engines modified for marine use. Any unbiased opinions out there? Thanks in advance, Scot"
 
"There are no unbiased opinion

"There are no unbiased opinions, only people with different experiences. But, having said that, the 120 Lehman is a wonderful workhorse. Many trawlers from the 60's thru 80's used the venerable 120 Lehman. They were also used in heavy trucks but were found to be ill suited for that type of use. The constant change in load wasn't good for that design. A boat has a constant load very similar to a tractor so it is a very good match.

These engines are fairly simple and heavily built as on would expect a tractor engine to be. 3,000 hours is pretty young for an engine which can be expected to get 10,000 before overhaul.

They are susceptable to overheat. You must keep the cooling system clean and in good repair. I don't mean they overheat often, I mean when they do, they blow head gaskets and develop cracks. The heat exchanger and oil coolers deserve regular maintenance. Be sure to open the petcock on top of the exhaust manifold to "burp" the air out when you refill with good antifreeze.

The 84 model will have an inline injector pump that uses a separate oil supply which needs to be changed regularly. Most of my friends and I change our pump oil every 50 hours, and engine oil at 100 hours or the factory recommended 200 hours. The pump takes less than a quart of oil, but it keeps that expensive piece of equipment working properly.

Clean fuel is a given for any diesel. Smoking, hard starting and poor running are symptoms of dirty fuel. Typically a Racor type filter is inline before the engine mounted CAV filters. I use 10 micron filters in mine which is probably just right for these engines. The engine mounted filters are 10 micron also so the factory thinks that is enough too. Some folks have bought conversions to put 2 micron filters on the engine mounted filter base. That probably doesn't hurt, but I don't believe the tolerances in these engines are tight enough to make a difference.

If the engine in the boat you're looking at has received decent care it has a long life ahead of it.

K"
 
Re: "[url=""]www.bomacmarine.com[/

Hello
i have a lehman 120 in my Beach Craft and no one this side in Belgium can recognize my engine number, this engine has a shaft driven injector pump, please can anyone help me recognize this engine. also i have been advised to leave off my valve stem oil seals as apparently they are not good on these engines.they become loose and slide up the stem, this is very hard to believe, i removed the head as i had oil in the exhaust, clean oil, i have no piston damage, all bores are good, i had my head skimmed and checked for cracks, all good.
my engine number is
5a8fc1d2/16
it is an fl 600, the fl is stamped on the head.
i do believe the oil is getting in through the valve guides.has anyone else had this problem.
cheers
George
 
Hi george,
the oil seals were never a problem except with age and heat they crack after thousands of hours.
Your engine is a dagenham 330 cubic inch and the serial # is stamped into a pad where the head and block meet justr above the inj. Pump and to the front. Starts with letter "s" and is six digits long i can tell you the year if you find it also most o the engines were built with an oil cooler (nine inches long and 2 inch dia. Connected with hoses between the oil filter and heat exchanger. This is the most common part for oil leaks into the exhaust. And is good for approx. 5 years or more.
Oil seals must be installed on the valve stems !!!!! These umbrella seals are designed to rest at the top of the valve stem.
Charlie w.
 
Hi george,
the oil seals were never a problem except with age and heat they crack after thousands of hours.
Your engine is a dagenham 330 cubic inch and the serial # is stamped into a pad where the head and block meet justr above the inj. Pump and to the front. Starts with letter "s" and is six digits long i can tell you the year if you find it also most o the engines were built with an oil cooler (nine inches long and 2 inch dia. Connected with hoses between the oil filter and heat exchanger. This is the most common part for oil leaks into the exhaust. And is good for approx. 5 years or more.
Oil seals must be installed on the valve stems !!!!! These umbrella seals are designed to rest at the top of the valve stem.
Charlie w.

Thanks Charlie
I found some proper stem oil sealsand fitted them, also is it possible my injector pump could be out of timing, its on a shaft, I started the engine up and now ihave a lot of smoke and I have fuel inhe exhaust, tail pipe, the motor rns very nice on idle and midrane but on high revs have a misfire, I do have diesel smoke a all rev ranges, I am a diesel mech and years ago we had crackd shimson a Volvo f10 truck fuel pump, what ihave on this lehman is th same a on those engines,
What do you think?
 
Hi george,
sounds like timing. On the injection pump drive coupling there should be a horizontal line. The timing marks are on the flywheel at the rear of the engine. There is an access cover on the right side of the f/w housing. Turn engine clockwise to 19 degree mark in access hole. Lines on inj. Pump coupling should line up. If not loosen coupling bolts to match lines.
Charlie w.
 
Hi george,
sounds like timing. On the injection pump drive coupling there should be a horizontal line. The timing marks are on the flywheel at the rear of the engine. There is an access cover on the right side of the f/w housing. Turn engine clockwise to 19 degree mark in access hole. Lines on inj. Pump coupling should line up. If not loosen coupling bolts to match lines.
Charlie w.



HELLO CHARLIE

I was wondering if you could assist. I am thinking of buying a Nauticat Yacht aged 1984

It is supposed to have a Lehman 120hp engine EnginesTotal Power: 120 HP
Engine 1:
Engine Brand: Ford
Engine Model: Lehman
Engine Type: Inboard
Engine/Fuel Type: Diesel
Engine Power: 120 HP


I was wondering where could i buy a Haynes Manual or a Company maintenance manual for this engine.. I am not too familiar with engines - but can use a spanner etc.

Best regards

Graham460

Not too sure how to get the reply

email [email protected]

Best regards
Graham
 
Hi graham, start with the lehman owners manual which should supply most info. Later get the shop manual if you need to tear into it.
Try marinegine.com or american diesel corp 804 435 3107
charlie w
 
Re: 120hp ford lehman questions TO CHARLIE

HELLO CHARLIE

I was wondering if you could assist. I am thinking of buying a Nauticat Yacht aged 1984

It is supposed to have a Lehman 120hp engine EnginesTotal Power: 120 HP
Engine 1:
Engine Brand: Ford
Engine Model: Lehman
Engine Type: Inboard
Engine/Fuel Type: Diesel
Engine Power: 120 HP


I was wondering where could i buy a Haynes Manual or a Company maintenance manual for this engine.. I am not too familiar with engines - but can use a spanner etc.

Best regards

Graham460

Not too sure how to get the reply

email [email protected]

Best regards
Graham

Hi graham, start with the lehman owners manual which should supply most info. Later get the shop manual if you need to tear into it.
Try marinegine.com or american diesel corp 804 435 3107
charlie w




HELLO CHARLIE FRIDAY 4TH SEPT 2015
Many thanks for the Information,

I have just emailed Marine.com Awaiting a reply


Telephone number - I live in the UK - But I suppose I can ring them when i get back from Working in Egypt, if they don't reply be email.
I just need how to carry out routine Maintenance - and Faultfinding tips..

I live near Liverpool

Thanks again
Graham
:)
 
Re: "There are no unbiased opinion

I have just had a mechanic inspection done on a 1978 120hp Ford Lemans diesel engine, which is installed in a boat which we are in the process of purchasing. The mechanic did not do a compression test on the engine as he didn't think it needed it. Have I cause for concern about this???? C.B.
 
Hi 2 cats, difficult to say without more info. How many hours on engine ? Was it ever overheated? Oil and filter changed every 200 hrs ? What type boat is it in ?
Charlie w
 
Hello Charlie

I have just visited that Nauticat 44 I m awaiting the serial numbers from the surveyor

Had problems with the engine - during Sea trial on full power the engine Alarm went off after 3 minuets


I also need the Fuel tanks replacing Not too sure on the cost


I'll come back with more infor tomorrow or Wednesday

Regard

Graham
 
Re: 120hp ford lehman questions FORD DOVER or FORD DORSET

Hi graham, start with the lehman owners manual which should supply most info. Later get the shop manual if you need to tear into it.
Try marinegine.com or american diesel corp 804 435 3107
charlie w



Hello Charlie

Just trying to find out Exactly what Engine I have

thumb_DSCN3697_1024 copy.jpgFord Lehman  PLATE STAMP   copy.jpgTOP View  DSCN5165 copy.jpgthumb_DSCN7646 Stamp on Engine .jpg









STARTER MOTOR WIRING

Number LUCAS
26352H 49 78
M50G 12Volt
 
Hi graham, you have a dover series. 135 horsepower. 2725 on the valve cover id plate and 826 on the block are all dover#s

nice clean engine but i don,t recognize the marinizer

charlie w.
 
Graham you got back to us on wednesday just 10 months later! But you finally got your answer. Are you still waiting for reply from the surveyor? LOL, Is she running up to par yet?
 
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