Ford Lehman FRESH water pump

We are refurbishing the engine cooling system on Beach House and have replaced the oil and transmission cooler, hoses, etc. Today after running the engine I find the FRESH water pump is weeping about a drop every 10 seconds and I know what that means. My question is, since American Diesel is closed, can the pump be rebuilt or is it easier and cheaper to simply replace it? What can I expect to pay for a new pump?* This is a 120 BTW. Thanks for any help. Chuck

-- Edited by Capn Chuck on Saturday 29th of August 2009 12:06:27 PM

Wait* .....* what* ...* American Diesel is closed?

They are closed for the weekend. How about some info on the pump. Any thoughts? Chuck

The problem isn't the pump but the connecting piece. The connecting part is no longer made so any money spent on the existing pump is at the risk of wasting this money when not if the connector fails. Replace the pump with the new one piece design and be done as I wish I had three years ago. The new pump I think was about $300.

That looks like the direction we will have to go. Thanks for the input. Chuck

Well, too late in the day for my help now, but you did emphasize FRESH water pump not RAW water pump, so I think the advice about the $300 replacement pump to forestall the pump drive problem is talking about something you're not dealing with right now.

You are talking about the anti-freeze circulating fresh water pump that the fan belt drives. And it is easiest to replace the whole unit as opposed to trying to repair. A friend needed one on a Saturday and found one at the local mobile diesel repair place. They do a lot of mobile marine engine repairs and had one on the shelf. That was lucky for me, as if he didn't find one I was going to have to drive 45 minutes each way to my boat to loan him my spare.

The good news is that you can probably go wherever you want and just top off the water every so often. You might even get away with leaving the pressure cap on the first notch and it won't even leak. DO NOT overheat the engine. Run a half hour, check, if not low run another half hour and check again, until you KNOW how fast it is using the water.

If you were in Anacortes WA tonight, you could walk over to my boat and pick up my spare. I'm hoping I won't need it in the next week. Otherwise, call around to the marine engine repair places and they probably have one in stock.

Ken

Ken, Thanks for that. There are really no resources where I am now so I will wait til Monday and have American Diesel ship me one. Chuck

AS long as you use ONLY ONE CAN,

Barrs stop leak should solve the problem till you find the replacement unit.

Sorry about that didn't catch the fresh water distinction

Bear in mind that there are TWO versions of the coolant pump for the FL120. One of them is the one used on the marinized version of the engine originally. The other one is the so-called "combine" pump, and is the pump used on the agricultural/industrial versions of the engine. They both fit, they both work EXCEPT that one of them (the combine pump I think) has slight difference in the shape of the pump body and so requires a slightly smaller diameter drive pulley. Since the pumps are normally sold without a drive pulley, if you end up with the "fatter" pump version but your current pump has the larger drive pulley, the pulley will contact the pump.

According to AD, the solution is to take a grinder like a Dremel tool and grind away just enough of the pump body to let the pulley clear. They told me there is plenty of metal in the pump body casting to allow for this. IIRC, the larger "combine" pulley has a conical front on it, which is one way to tell it apart from the slightly smaller pulley.

You can put the smaller pulley on the "larger" pump, you can (I believe)*put the larger pulley on the "smaller" pump, but you can't put the larger pulley on the "larger" pump.

Apparently the only accurate way to tell if the combine pulley will clear the replacement pump you get is to actually try it.


-- Edited by Marin on Monday 31st of August 2009 12:38:58 PM

When I talked with Bob Smith this morning, he is still in business, he made no mention of any modifications, he just said he would ship me the pump. I doubt this engine has anything but marinized parts. Chuck

It was his son Brian who told me about the two different pulley sizes and the possible need to grind away a bit of metal if you have the larger pulley. Our boat, which has its original engines but not its original water pumps of course, has the larger pulleys. When I ordered a spare water pump from AD, Brian warned me about the possibility of the pulley not clearing the housing on the pump body and the cure. According to Brian, it's not an uncommon situation. The replacement pump you get may be of either size--- it's my understanding they have the same Lehman and Ford part numbers and what you get is whatever came out of the box AD got (or whichever pump they rebuilt--- many of the ones they sell are rebuilds).

I recall that he said the giveaway as to which pulley you have is the hub.* The larger pulley (I believe this is the so-called "combine" pulley) has a coned center that projects forward of the pulley itself.

-- Edited by Marin on Monday 31st of August 2009 08:03:08 PM

The current pump has a recessed pulley with what I can only describe as a coffee cup size and shaped extension froward of that and a small round piece that sits in the center like a nose and 4 bolts hold it on to the pump. Don't know if that makes sense. Chuck

That sounds like the pulleys that are on our pumps.*If so, from*the description AD gave me, this is the larger, "combine" pulley.


-- Edited by Marin on Tuesday 1st of September 2009 07:18:10 PM

Better yet, here is a photo

http://tinyurl.com/kmnu6m

Chuck

-- Edited by Capn Chuck on Tuesday 1st of September 2009 09:03:04 PM

No, that looks different than ours. The nose cone on ours is shorter, more steeply tapered, and is closed at the front end. So now I don't know whether yours is the large or small pulley.* Another difference is that the drive pulleys on the crankshafts of our engines are much larger.* But our engines are 1973 so who knows what changes were made in the following years.

If you have not already thought of this, when you have the pump off you might want to thread another drive belt over the hose and then wire-tie it back to the engine (ours has a lifting fixture that makes a good place to tie the spare belt). Because the belt runs behind the hose from the manifold to the header tank the only way to remove and replace the belt is to disconnect the hose, which dumps hot coolant all over the place which you then have to replace. Whenever our diesel shop has to drain the cooling system of an FL120 to work on it they take the opportunity to disconnect the hose and thread a spare belt over it and wire-tie it back to the engine. Then if the regular belt should break at some point the owner can install the pre-threaded spare belt and be on his way without having to disconnect the hose.



-- Edited by Marin on Tuesday 1st of September 2009 11:42:31 PM

That is a great idea. I have pondered the issue with the belt and that will solve it. Many thanks. Chuck

Here's my 1980 engine and water pump. It*has the spare belt prethreaded that Marin talked about. You can just make out the plastic tie that holds it securely to the hose and then it lays back out of the way between the small alternator and the block. I think my pump looks like Chucks picture rather than Marins description.

Ken

Yes it looks like my pump. It arrived today, so will install it tomorrow. I really like the extra belt idea. Thanks to all. Chuck