Thanks to all who posted about what engine I should use for my 49 F-3. I will rebuild the original flathead 6.

Now to my new question. A friend was going to sell me his flathead V8, but since I'm rebuilding my 6 I don't need the V8. I said I would try to sell it for him on the internet. The problem is I have no idea on the value of a flathead 8 that needs rebuilding. The engine is complete except for the carb. Can any of you tell me what a flathead 8 is worth?

Thanks,
Danny

 

I've seen non-running flathead V-8's sell for as little as $500 (maybe even less). They are prone to cracks, and it is usually a crap shoot for the buyer. I've also seen completely rebuilt ones with performance parts go for over $5,000.

 

$100 is what they sell for locally, unless the've been proven crack free. The only flathead worth anything really is the 255 Mercury, and that's just for the crank.

 

Flathead 8s are a funny animal. I have talked to people who say they can buy them all day for around a $100 then the next week I will talk to someone who says you're lucky if you can find a stuck one for less than $500. I would think an in the vehicle running flattie is worth around $400-500. If it's sitting in on the floor in a garage, and loose, I would think maybe around $150-200. I like to hear an engine run before putting money down on it. If it's rebuilt, with reciepts, I would say it would be worth $2000+, that's barely the cost of of parts and machine work.

FWIW, I sold a stuck flattie a couple of years ago for $250. I was hoping for $25 but I left the guy make the offer. I told him to make an offer and I wouldn't be offended. He stopped by a year later and told me the engine was complete junk, it was rusted throughout and there was a mouse nest in the oil pan. You just have to find the right person.

 

Is it an 8BA/8RT, or an earlier one? (What year)

 

You just never know what you are buying or selling unless you can fire it up and see for yourself and even then it might end up having a bad cracked block. I buy them for $25-$100 usually without anything but a visual once over. Sometimes you win but mostly you lose. My main goal is to salvage what I can. I sell short blocks that have been tanked and fluxed for $450-$750 depending on how they mike out. A good solid runner that don't smoke or overheat is worth about $1000-$1500. If it is rebuilt and you have the build sheet on it it is worth $2500 and up depending on specs. These are just general parameters that I use and I have been buying and selling these motors for a while. It is mostly a hobby that mostly pays for itself but every now and then I take a hit and every now and then I make a score. I don't do it for the money but because it is better than golf, bingo, or drinking and chasing women, IMHO. Good luck and in the world of flatheads common sense is going to be your best tool.

 

Many of you talk about cracks in the flathead 8 blocks. Are these cracks in one general area that I can look for and will they be visible, or can the cracks be anywhere. I don't want to spend the money to have it maganafluxed to find cracks if selling price of the block will just barely cover the cost of the maganaflux.

The engine came out of a 52 F-2. I have not looked for engine codes to know exactly what he has. He did say it was the 100hp version. I'm not sure he knows what he is talking about. I plan to look at it this weekend (and maybe take pictures).

Thanks again,
Danny

 

You can usually see the cracks once you wirebrush the block surface, but not always. Keep in mind many cracks can be plugged successfully with various chemicals added to the water, as long as you aren't going to use a blower! For an everyday driver, many cracks just get plugged by rust.

The ones that are bad are from a valve seat to the cylinder bore. These are expensive to fix if they are actually allowing water into the cylinder. The most common ones are those that are on the head bolt hole between #2 & #3, and #6 & #7, but don't connect up to anything. (I have this crack between #2 & #3 on mine). These are just because the deck is thin there. As long as you can get proper torque on those bolts, you're usually OK.

A completely separate type of cracking is along the oil pan rail. These are almost always from water freezing in the jackets. There is no fix for that.

Another thing is that many apparently good-running flatties have cracks and they don't show themselves to be a problem until they are discovered after a thorough tanking and inspection. The tanking process can clean out the mud that's plugging them. That's why as mentioned above, there is no substitute for seeing them run, preferably under load.

 

My "good" 255 Mercury I'm building for my truck is cracked just like ALBUQ F-1's is. The machinist who did the work (and worked on them when they were new) told me not to worry about that. I junked the original 239 8BA because it was cracked between the cylinder and valve, with a missing chunk.

 

I've been looking in the N. CO area for flatheads for a few months now, runners are going for around $500-$700 if you can hear them run, I haven't seen to many rebuildables in the area, some in KS have been going for $200-$300.

My uncle bought a complete runner 21 bolt with a tranny for $800 in Ft. Collins, I bought a '51 F3 with a great sounding runner for $600 in Holyoke. I'd say you could get $200 out of it if it can't be fired and looks good otherwise.

 

If anyone is intereseted I have an 8Ba in my 48 f3 that runs and I am taking out. I have no history on motor it is as I bought it. It has studs not bolts holding the heads on dont know if that means anything

 

Are the water outlets on the heads in the center of the engine, or at the front? I don't know of any 8BA's that used studs. How many studs are there? It may be a 59AB, which would be worth some serious money if in good condition.

 

I saw one this AM on Craigslist, in the Albuquerque area. The guy listed it as a Mercury flathead that was running when he parked the car in 1962. He is asking $1500.00.


Yikes.

 

I have found that flatheads are pretty hard to sell on the internet, it's probably just me though.

I agree with everyone that has posted , some people think that if it turns over and looks good it's worth a fortune... others only if it's not cracked (most of mine that have been cracked were cracked between the waterjackets and the cylinder). I have bought most of mine in trucks not running, or from a farmer that has had it sitting around for years. Usually I pay about $100.00 for a good lookin' block, and $300.00 for one in a truck (not running). I don't know what you guys have been paying, but I have bought a few only to find out that they were cracked pretty bad.

Well, hope you sell it.

 

I might call the guy just for grins. Not that I'd likely buy it, but you don't see them come up very often, hate to just sit and watch it go by...Claimed to possibly be a "Canadian" block with heavier walls, not sure that is a fact. If it were a ready to run clean Merc engine, $1500 would be a deal IMO.

I would want to see the crank and bores before I'd pay Merc prices for it, it could be a Ford with Merc heads, I've seen a bunch of those. People put them on thinking the Merc heads are better, mostly, but also some cheaters/posers taking the cheap route to Merc cachet.