Sad day- Last week,on the way home from our wedding weekend,I started the truck and it was randomly misfiring. It had the OG plug wires,and a buddy was foolin with one,so I figured that was the issue. Well,all new plugs/wires later same issue. Busted out the compression tester,and found nobody home at #7. This is my first Flattie,and it has always run perfect...and I mean perfect. The plugs I pulled looked mint and showed no signs of oil consumption with perfect colouring. The engine was a Ford replacement,done way back in the day. I have never opened one of these up,and I am ***uming I have a valve bust,or hung up. Truck as never really had much for blow by,so I'm pretty sure it should be a valve issue. I need some of the Flattie guys to chime in here and point me in the right direction. The truck is a keeper,so I wanna fix it right. I had also always kind of wanted to drop a detroit diesel in the hole(see video),maybe nows the time? http://youtu.be/K2zwd1iazvU
If you want an opnion ... keep the flathead... Rebuild it , maybe hop it up some ... Of course It ain't cheap.
I would like to keep the Flattie,but have no idea what Im in for. I am sure the motor is good except for that valve. Has great oil pressure,hell it even gives up decent mileage. On the Detroit,I'm just saying its a cool option.
A former good running, no smoke flahead that now might just have one burned/hanging valve? I'd be pulling the intake to start with. If it is valve related, I can't see any money worries.
I wish I could give you a cost but I can't - It's an 8ba or 8rt so you'll be able to get parts. I doubt it will cost more than a detroit conversion . It still runs right? SO you're way ahead of most flathead guys.
Sad day, These are easy to work on and you may not need to pull the engine. Could be a sticky,stuck valve.
What am I gonna see by pulling the intake guys? How do you get at the Valves on these engines? And yes,it is running-was running perfect. Would idle at like 400rpm before,never any issues till now. Maybe a stuck valve? Im sure these things dont like running on ethanol enriched unleaded.
If you pull the intake, you can see the spring, check to see if the valve has lash clearance, see if the cam lobe is working.. If you pull just the head, all you can see is the head of the valve, but can't check lash, etc. If the valve needs removing, both the intake and the head has to be removed.
Pull the bleedin' intake & see if those valves move when you crank the beast over. Flatheads are like hammers, you can beat the **** outta them & they still run. Doubtful that you have anything more than a ****py lifter or a bad spring.
Look down the plug hole. Is a valve open? Rotate the engine. Does the valve stay open ? If so put the short end of allen wrench against the open valve and gently tap the long end freeing your stuck valve.
I agree. Take off the intake, you can clean things up in there with kerosene. See if the vavle, probably the exhaust vale is travleing full range. Lossen them up, might be a broken spring. Then you can do a comp test, to see if you have made any progress before you remove the head. You may not have to, so do the intake first. If you wash things up with the kerosene, make sure you do and oil change before you run it. In the old days they would thin oil in the winter with it.
Pull the intake, it will be aparent if there is a valve problem. I guess losing a hole in a flathead is better than finding one!
Ok, This is good news. For some reason,I ***umed the only way to get at the valve was through the bottom end. I gots a feelin its a stuck valve,just by the way it happened,and the fact that there is "zero" compression in that hole. If it was 40 PSI,I would be thinking it was worse. The old lady wont have me doin any of that Detroit ****,so lets forget I said anything about it. She's got a wide on for the Flattie,so its stayin.
If you must run the ethanol gas, use an upper cylinder lube..... I use Lucas in mine, just add a couple ounces on every fill up.
She is a keeper. Anyways,if there was a clean sheet of paper,what can a guy do with a 239 without breakin the bank? The truck has 5.18 gears,which means it spends more time than I like over 3k RPM. I Have a brownie that I am planning on installing,that was gonna happen this spring until the dead hole happened. The thing runs so darned good I am afraid to mess with it too much,but I would love to see an old supercharger under the hood,or a functional multiple carb set up.
Most likely the valve is stuck open as the others have already said. A burned valve would probably have shown some compression. I'd do as they said and pull the intake and crank it over and watch the valves and lifters in that cylinder to see what they are doing. If the valve is stuck take appropriate action to get it unstuck. If the valves appear to be working and the clearance on the lifters seems to be right I'd go ahead and pull the head to see what it looks like there. As much as we try to make these things rocket science now remember that it was the norm for mechanics in the Ford garages to roll one of those trucks into their stalls in the shop at 8 am and drive it out before lunch with a fresh valve job and tune up done. That was a daily occurrence in shops all over the country in the 50's. By that I mean don't panic, you will be out the price of and intake gasket and a head gasket but it shouldn't be a long term or terribly expensive job unless you find more issues when you open it up.
This exactly what I just did with the flattie in my shop. I'd check the valve operation looking through the spark hole first before tearing it apart. It's the easiest and cheapest thing to do.
So,as far as "unsticking" the Valve,just wash it down with kerosene,and make sure the spring is not broken? Whats to keep that from happening again? Are there issues with the guides in these things?
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