Technical Scored my first Merc flathead

Responded to a cryptic week old FB Marketplace ad the other day titled "1950 Ford ?" The cloudy pic was of a flathead. Glad I checked it out!! Ended up with a fair haul on New Years Day.
I'm confident so far with calling it a Merc...I've just measured the cylinder stroke as the heads were already off. I plan to drop the pan and confirm another indicator (6in counterweight) or whatever reviels itself to me.

I did see an issue in the "clean lifter valley" one key/clip is missing on an exhaust valve. Can't see it anywhere in the valley. Was that a common occurrence? Or?

I also got a nice set of Weiand finned heads that'll need clearance to run atop.....will match my 2x Weiand intake nicely.

 

Kinda odd the pan, heads, intake, and pumps are '52-'53 Merc, but the flywheel/PP is Ford Long, not Merc B&B. Looks like a pretty nice flathead!
I would suggest using a different way to lift the short block, as your 3/8" bolts through a chain result is side load that could crack the intake bolt bosses. Better to use a flat plate or angle irons bolted in place of the intake, imo.

 

Thanks Bob for those observations...I wouldn't have caught those updates. I've got to figure the numbers out to narrow it down more. On a positive note I got really good rotation. Will drop the pan soon and look at that end. I'd sure like the opportunity to just hone the cylinders and avoid the machine work.....but I'd like to consider a cam upgrade too. However long the road I choose is... I may put the original heads and intake and try a run or so. Spent 2hours blowing and vacuuming crap out of the water passeges... it's pretty clear now I think....but do plan to go back for another round.
I got it on a stand now.

 

So I got to taking a better look at the motor.
A question for the group....one of my valve guied retainers was missing...not sure when or how. But on a closer inspection there's some deep pitting on the valve guide bushing. Pictured below....I'd assume this needs to be replaced or ?

Here's it is on the stand....very clean I believe. I am considering if it could get a diy cylinder tidy, replace the bad/missing valve components...new gaskets and run.... or am I pressing my luck?

 

Oh...I made this to better support the block ad I fiddle with it. 3/8s steel plate.

 

And finally...any insight on sizing up the requirements on "clearances " for using these Weiand heads? I don't know anything on the current cam...if that a component of the answer. It does have a 4in Merc crank.

 

Can you use a little children's clay in the combustion chamber, rotate engine, to get a good estimate if valve to head clearance?

 

Good idea. I had another recommend the same thing. I'm studying up on it now. Thanks

 

The intake that you pictured is for an earlier flathead. You can use it on your engine but you will have to add a PCV system or some other means of venting the crankcase.

 

Are you talking about this intake?

 

Here's a new question to start the day with.... I have spent hours so far dislodging and blowing rust scale out of these water passeges to clear them out. At what point does the level of pitting tip the scale of rebuilding? Here's an example pic of a deeper pitted area at the top inside cylinder wall...I'd suspect that the remaining cylinder wall thickness is an 8th to 3/16 in these deep pit areas. Thoughts on when to walk away from a block with a significant level of water passage pitting.

 

Kinda like what they did here but hopefully a tad more elegant....

 

Just going off of the piston tops I think you can get away with a honing of the cylinder walls. That and the crank looks really clean. I think you scored big time.

 

The stock Mercury cam is a good choice for a heavy car, like a shoebox etc. I don't think the rust in the block looks too bad. You should at least pressure test it before you make any decisions. As to the valve train, someone at some time decided that they'd do a quick fix on a valve or two and found out how difficult working with the flathead valve train can be.

 

You are thinking about putting the heads back on that rusty deck surface and running it? Waste of time to me. And they don't give head gaskets away nowadays.

Maybe the pistons and bearings are good. Maybe the cam and lifters will be fine. But I think you should completely disassemble and clean. You can keep all the parts in proper order and put them right back where they came from. But get all of the block clean first.

Then maybe lap the valves (great time to check clearance and grind tips if needed), hone the bore and new rings, and a new gasket set.

 

^^^^^ What @alchemy says. While you're at it, take a look at the head bolt holes at the front of the engine on the passenger's side. Top front bolt hole next to the exhaust valve looks like it's stripped, the one next to the cylinder looks the same and the one between the front two intake valves looks like it's pulled. There is what appears to be part of the bolt hole standing proud of the deck surface. It may just be the pictures but it sure doesn't look right to me. Run a thread chaser through all the bolt holes and get all the crap out of them.

 

I agree a light hone to the cylinders should clean em up nicely. I believe I may have got a little lucky with this 1 week old Marketplace ad.

 

Your exactly right on the one that has been pulled above the surface.....as for all of them.....I need to check. I'd guess that with any thread damage a potential exist for bad sealing of the head and possibly leaks. I will look into them all. Thanks

 

I only noticed one valve issue so far since it was happy to slip out without that keeper. But noting the amount of pitting on the top of the guide.....I'd say I might better pull and inspect all

 

Another thing that is necessary. Use thread sealant on those bolts going back into the water passages. If you don't, you're going to find water in places where it's not supposed to be.

 

If I were to button it up as is minus a few obvious nessary repairs...I'd go ahead and try to diy clean up the decks. I'd not let them go at their state.
However...the more I read here the more I'm inclined to get in a hurry to button up.

 

Also, don't chase the head bolt threads with a standard tap. Use a cleaner tap. You can make one by cutting a slot in a bolt if you don;t have access to a cleaner tap. And when you bolt the heads back on make use you seal the threads so as not to get water leaks. My machinist recommended #2 Permatex but others have different thoughts. JMO.

 

You didn't mention any cracks, You are VERY lucky. Anything else can be fixed.

 

Can't say on that yet but at a minimum I'll get the ol wire wheel out and clean up t ok check....not a legit magna flux

 

Always heard the head bolt threads are Ford specific rounded threads & a good cleaning as 51504bat said is the preferred method.

 

Good advice here. I would add to not get in a hurry on your flatty. Tear it down, clean it well, magna-flux it thoroughly on all sides, inside and out, especially in the valve seat area under the valves, and maybe even sonic test it. Then you will know 100% what you've got. I know it's a lot of time and work, but it will save you much more in terms of time and headache in the long run. I'm hoping you've got a cherry one on your hands -Seth