After years of negotiating, and almost begging.... I have what I thought was the best find for a flathead motor. 1951 Mercury Flathead V-8 This motor was in a truck my grandfather bought new. It had never been rebuilt. Always ran very reliably, working on the farm, until the day I took it apart. To my disappointment, there are however a few problems with the block. - One of the valves wore so badly that it wore through the seat, and actually wore the block. This would have to be built up, welded I assume, before being machined back as part of a valve job. - After cleaning and inspection of the block, I have what appear to be 3 small cracks between water passages, and head bolt holts. The attached picure shows the worn valve and the location of one of the cracks. The crack is located between to 2 cylinder bores on the left, between the water passage and the head bolt hole. There are 2 more cracks of the exact same type. The picture was taken before cleaning the block. Is the valve repairable? What is the best method of fixing the bad valve? What about the cracks? Some internet sources claim that these cracks are VERY common and do not necessarily need to be repaired. Is this block worth saving? At what point do you begin searching for another block, or just buy a French Flathead block? Who would you suggest do the work? I'm from Sarnia, Ontario, Canada. It would be nice if I could find someone relatively local to do the work. I'm a new member to this forum, who already has one restored, running flathead that is wonderful to drive. I'm trying to start my next project. I'm just wondering if this is a too big of a problem to continue.
Block may be later than '51--Ford gradually tapered off on using hardened seats after 1948, but I think '51's still had them on the exhaust... Hard to tell contour of that failure as it continues up into the dish flow area, but unless it's reallydamnbad, the repair would be installation of hardened seats on at least all exhausts. Ford was overrun by cost cutters hired from GM in this post Henry era...early blocks with seats rarely need more than a light buzz to clean seats. Hard seat installation is a routine machine shop process and should be easy to get done. Cracks between bolt and water holes are common and generally considered harmless--the old joke is that those particular cracks actually had Ford part numbers. I think the block is quite saveable unless the erosion from seat into bowl or outer dish areas is REALLY deep.
Yes those stud to water jacket cracks are a non issue. I sure would have that valve seat repaired. Listen if they can fix major cracks in these, they can easily repair a worn seat issue. Definitly, before any major machine work. Get the thing pressure tsted and magnafluxed. good luck, welccome and good score. Now wher's this other car with the flathead and tell us something about yourself. straight..gay ??? got a good looking sisters, daughters or wives? Show us pics of any or all above please.. welcome to the hamb! PJ
What Bruce said.Clean rust off and post another picture.It don't look like it ran much with ( bent?) valve.
Look at the bright side--if you do have to find another block, at least you've got a Mercury crank now. Since Ford and Merc blocks are the same, finding a bare block isn't that impossible. I do believe that a competent machine shop can salvage the one you've got, though.
I kinda thought this would be THE block. The truck was in the family, and worked on the farm from new until I drove it into the shop to pull the motor. It ran and worked well. I was surprised to find the valve problem. I'm looking for a good shop locally to do the work. None I have found want to touch it. Flatheads Forever in California say they can fix it without problems. But shipping each way is $200. That is money I would rather spend on the engine. Any suggestions for a local shop? As for me: I'm married, white, 28 years old. My wife is cute, her twin sister is single....... I do have a sister, but I wouldn't go there. My other flathead is in my restored 1940 Ford pickup. Flathead, 3-speed, dual pipes, bright red and chrome. It is driven often in the summer time. It was not redone to sit in the garage. I'll hunt for pictures.
Canadian Merc pickups used the Merc name and the Ford 239 engine. Unless you have a sentimental attachment to it Id look for something that "may" be less expensive to fix and build. As far as valve seats, they were all gone by the middle of the 51 year in the US, cant say about Canadian builds as they had a lot of autonomy to do things different.
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