Rebuilding a 300 L6

That is if it is saveable... picked it up from demondog last weekend in the hopes that I can replace the tired 240 in my van. The situation... 66 Ford truck with collision damage on the frame being sent off for scrap... 300 still sitting mounted in there. So the motor ran, but that was at least 20 years ago! The good thing... the motor hasn't been sitting on the ground. The bad... well, it is seized, to say the least. Here's a few pics of the teardown!


1965 engine block


crud found upon removing head, pitted rust on 4 & 5


crud / rust close up


after blowing it out


underside of the head

I've soaked the crank bearing surfaces in ATF and have the piston crowns now soaking in ATF (about 36 hours now)... still not budging. I may just take it as is to get tanked. Hopefully, it's a good candidate for a rebuild!

There have been a number of threads on the HAMB for unsticking engines.
Along with ATF, try some diesel (50-50).
Remember that the pistons will be discarded for the rebuild and that they should be considered sacrificial to save the block.
I'd soak the undersides too (flip the assembly over) to try to free up from that side and the wrist pins. Just remember that there is fluid in the top before turning!

Just curious, but are running used 300 fords scarce enough to warrant spending $$$ on rebuilding one in that shape ?

Finding one of the vintage years from those vans and trucks are scarce here. Can find lots of newer stuff, but different intakes and such.
He wants to keep it close to stock. The motor was free.

Rod, I did do that... Thanks. Actually got pistons 1 thru 3 removed last night.
4 thru 6 don't want to budge though (yet).

Digz... yeah, what demondog said. I'm going to try to risk as little money as possible. Who knows... maybe this block has already been bored over, and the rust in 4 and 5 is catastrophic (can't bore over anymore)... In that case, I have to get my Grimstone van done ASAP so I can park the ambulance. But maybe the 300's good...

I should be able to transplant the manifolds from off the 240, being that the age of the blocks are similar. It would be cool to find a later 300 though. Can't afford it right now though.

I think if I was to do it right, I would just rebuild the 240 so the van keeps the original engine. Maybe eventually, that's what I'll do. I am torn though... keep it completely original, or toss in an extra 60 cid? If I lok into my crystal ball, in two years from now, the 240 will have been rebuilt and put back into the ambulance, and the 300 will be good to drop into another Econoline!

If nothing else demondog, I am having fun tearing the engine apart. Your gift of the 300 is very generous. You may end up getting it back for one of your pickups!

If this engine is too far gone or will cost too much to fix, I won't bother... I'll get my other van on the road, and then try rebuilding the 240 in the ambulance. I don't think I'd go to the trouble of having it sleeved.

I don't think I would be as committed to keeping it original if it weren't for the special history of the ambulance. Any other Econolines are fair game for modernization! I might even go EFI L4 out of a Ford Tempo or something if it could get a van rolling better than the old 144.

The 300 cyl. looks like I see some cross thatching from a hone job. Seeing those lines makes me think the engine was done or was taken care of before the accident that parked the truck.
The real way to know is have it tanked for a night and let the rebuild shop look it over. Like the shop I mentioned to you. Ask for Calvin. He knows me.

Boy, I let this topic slide for a while... cool offer Scott... would only require some doghouse mods (oh and motor mounts, oh then tranny mounts... but could be fun, right?)!!!

I fear that I am wasting my time with this block... the pistons in 4, 5 and 6 do not want to come out at all. I'd almost bet that this truck was driven around on a farm with the frame all messed up, until the engine died... There was lots of gunk clogging up the water jacket at the back of the block, and I suspect that the engine overheated either to the point where the piston skirts expanded OR the piston rings have gotten wedged between the piston and cylinder wall... I'm expecting a bit of carnage there. It's been a couple weeks of soaking and pounding... The rest of the engine came apart fine.

I guess I'm back where I started... my 240 needs a rebuild, and my best bet is to find an old F150 with a 300 in it, hopefully for a couple hundred tops. Wish me luck.

As bad as that block is, deeply scored and rust, your gonna end up with a rebuild, pistons are going to be toast,, here are some thoughts???????
The 240 and the 300 dimensions are identical, only differences are in the crank and rods, front pulley, with the 300 usually a double pulley crank dampner.
Heads are different of course. Of these, main important difference is adjustable rockers or non adjustable rockers. ALWAYS use adjustable, when a valve job is done, and the head milled it changes the height of the top of the valve in relationship to the cam lobes. To properly "SET" that height, you grind the tip of the valve to a specific height, using a special height gauge for it. However, it doesn't account for head gasket thickness and or any milling on the block and or the head,,, you CANNOT adjust it EXACTLY where it needs to go,, period. The difference in the heads also include different shaped combustion cylinders, and size also. So,, I try to use an early 240 head, to bump the compression up slightly, and get adjustable rockers at the same time
Reason for mentioning, is suggest you use your 240 head on the 300.
Having owned an automotive machine shop, I have lost track of how many heads and engines I have done, and can speak from the machinists side."
You will need the 300 crankshaft if it is "VIRGIN", meaning never ground yet, as you will want to get it reground as little as possible, IE: .010/.010 the best.
Also, you will need the rods. EVERYTHING else is the same. Uwe HYPERTHETIC pistons for the build, as strong as forged, however you don't
need to bore it with as much piston clearance to compensate for forged pistons expanding more when started and gettting up to running temp.
Also, when you torque the flywheel or flex plate,, MAKE SURE YOU do it in steps, and also, IN INCREMENTS like you are supposed to,, the big sixes are VERY PRONE to the rear seal leaking if you don't. In fact most good rebuilders already install a seal saver just to be on the safe side. You won't believe the torque differences between the two motors?????? completely change your tire and gear sizes, CRUISE up hills without downwshifting and putting your foot in the carb.
vic

We're back ON AGAIN... the last three pistons gave up their grip. Luckily, it appears that it was the skirts holding the pistons in, rather than the rings having blown out.

Now, I have the block stripped and the crank ready to be checked. I'm anticipating getting the cylinders bored over, so I was less than gentle removing the pistons... they are done! I wonder what the shop will say about the rods and crank though.

Almost finished disassembling the head. Quick look at the block with a straight edge tells me that it'll likely need to be decked too.

I cannot tell if this engine is a 300 or not... I'm told it is. I guess if you were to look back at the pic I took of the head, that you may be able to tell if it's a 240 head or not.

I don't plan on separating the existing engine's stuff to hop up the 300... as a matter of fact, the 300 is a temporary solution. I want to put the 240 back into the Shambulance when it gets rebuilt... I made a promise to try to keep it original. Besides, the 240 / C4 combo has good kick to it! So maybe at the end of the day, demondog will reacquire the 300 for his Econoline! You are right though, I will probably like the way the 300 feels compared to the 240, much like how I liked the difference going from the 170 to the 240!

So anyway, it's GAME ON!!!

I dropped the block, crank and pistons off on Monday. First thing they noticed is that from the crank and connecting rod length was that the engine is a 240, not a 300.

Quick check with the shop, the crank would need to be ground 10 10, and the cylinders need to be bored out. They will check this against the cylinder with the most rust. Now, they did say they have a 300 crank available. So they will price out the short block rebuild as a 300 rather than adding the expense of grinding the crank... but the bottom line is that the engine is good.

Also heard from the other shop out in Warman... sound like good guys who work their shop outside of their day jobs. Their prices are much better, and I may leave the other engine in their care. They also sound confident that they can repair the head I broke the valve guide on. So I will probably go that route too.

The 240 I got for free to rebuild... before:



After getting tanked, bored .060 over, and detailed... will be fun to build this!!!

any updates corey

Got a little more information on the FordSix.com forum... Apparently back in 65, the crankshafts were different. If I was to happen to buy a crankshaft from say 1970 240 or 300, I would have to have a machine shop trim it to fit a particular journal... cranks changed after 66 I guess. So I will get the existing crank tuned 010 over when I can afford it.

No other news for now, except my van is giving me fits, and I wish I was ready to swap this one in tomorrow!

I figured the jugs were just rusted shut,, have smashed pistons out of blocks like that my the hundreds,,,LOL... Big sledge and a 4 x 4 stub,,, he,he,,, lots of wd 40....
You should never regret bumping up to a 300,,,,,,,,,,,,, its NOT the cubes, its the TORQUE,,,, the 300 will outrun that 240 two to one, and you wont believe the difference in gearing!!!!!!!!!!!!!! short example,,,,, strong 240,, always looking for one more gear at 80??????? 3:50 gears,, rocket out of the hole. Changed to 3:25's,, to get more top end speed,, fair to a dog out of the hole, LOOSER up the hills, great at 90 on a FLAT ROAD. Wanted my 3:50's gears back.
Put in the 300 (stock),,,, now considering going to 3:00's,, keeps pulling 80 easy,,, up long grades,,,,,,,,, its a torque monster, and twice what the 240 could ever think of...
A good point on a 300, is to put in an ADJUSTABLE valve 240 head, little beter combustion chambers, and a little higher compression,, easy way to get the max out of it,, all the rest of the stuff,,,, is a bolt on no brainer,, consider of course a good 4 core radiator is a must,, even better a Taurus electric fan and shroud setup.. the very least a fan shroud, and the six blade fan. Forgot also,, use the GENII 300 air cleaner, its a bolt on, with a fresh air intake port, and a paper filter..
vic

I almost stripped my current engine and used it's internals in the "new" block... I broke down, but was able to get my engine to run putting my Holley 1904 in place of my Ford 1101... So I'll be buying a reman this week to keep the van original.

Good points on the 300, but sourcing all the guts has me scared, plus I have all the parts to build it as a 240 (except the pistons which I have access to)... I learned that 240 and 300 pistons have different crown heights, and pre 67 pistons have smaller pin diameters than newer ones... I can't afford to buy all the new components (crank, rods, pistons). I have to do all this on the cheap, as my living expenses are now impacted by the fact that I lost my roommate that covered $500 of living. I hope I can find someone very soon so I can put more resources into my engines and to buy some new music gear.

I have a new set of .030 over pistons, and a rebuilt set of rods,, need to dig em out, and confirm they were 300's????????? I bought them both on e bay a LONG time ago in prep for a build,,,, will get the part #'s tomorrow IF you are interested????????????????. How does $50 bucks sound for them??????? On my own I pretty much just go a small block anymore. Less hassles about the same $$$$$$$
vic

Darned,, forgot also, have a LOW mileage later 300 head (pedestal rockers), ex UPS truck cylinder head I had bought also,,, dont even think it really needs anything except some paint,, LOL,,, $100 same as I pd..
vic

This block is already .060 over. The one currently in the van remains to be seen... it's still turning. At any rate, I don't have a block they would fit. Plus I'm a long way from CA to ship a head! I've gotta fork over a couple hun for my new carb this afternoon, so I'm broker than broke... I can't imagine being able to afford changing either of these old 240 blocks to old 300 blocks.

I wish I could get an old UPS engine though... that 300 head is surely a decent investment.

If your new block is standard and the jugs aren't all beat up,, it may take a .030 bore,, but they usually go .040 to avoid the last one that wont clean up,, LOL,,
You are more than likely gonna bore youre new block anyways,, thats why I offered up the pistons.....The 300 is a stroker, so doubt a simple re-ring would hold on a normal rebuild let alone beating the pistons out of it,,meaning I SUSPECT rust pitting where the rings were sitting????
vic

I'll keep it in mind. For clarity, the "new" block is the one currently in the van that is tired... I bet it's a standard bore. If I can find a pre-67 300 crank, then we're in business! I would probably use one of the 240 heads I have.

The "old" block, which has the green pan, lifter cover and valve cover, has already been bored .060 over in the clean-up process... engine had been sitting for probably 20 years. It's also a pre-67, so I'm dealing with the same crank journal issues from the design change.

My plan is to rebuild the .060 over block as soon as I can afford it (at least build up the short block with the new pistons and have the shop machine the original crank from it). When I have it ready, I'll swap it into the Shambulance and see where I'm at with the current block. That one, I'll probably rebuild it and save it either for myself or for DemonDog (we're in kahoots, being the only two Econoheads in our locality, he's helped me get vans and parts and store stuff). So both engines have a future, only I can only afford to go the 240 route with the green engine right now.

I picked up my carb today, but it wasn't quite plug-and-play. It's installed and not leaking, but van wouldn't start yet... didn't have many daylight hours to fiddle with it. Maybe tomorrow...

Hmmmmmm,,, it must be harder to get engines there??? I can get 300 VIRGIN stripped engines ( block and head only) for easy $150 all day long. I am not sure I would really like a .060 over bore block???? As you say????????? it has already been bored,, that SHOULD MEAN you already have the pistons which I think that is what you are saying? ,, OR, did he bore it close and is planning on a final hone to size to match the pistons when you get them???????? I have a reason for asking. First off, all piston sets are not kept to that tight of a tolerance, so usually don't finish sizing without the pistons in hand to measure. ALSO I use the hypertectic pistons, as they are as strong as forged pistons, however you don't have to bore them out with extra clearance (slap and noisier until operating temp) like needed for forged.

If it were myself, and here, I would simply buy a virgin 300 short block here for say $100 bucks. Take it home, and bore it out automatically to .030, take my 240 head and put it on it, with a 300 carb (not the 240), use the big bore 240/300 intake and run it forever???? Just throwing that out there to chew on???? Point being, everything from the 240 is a bolt on, to include the gears,cam and lifters,, all the same. no hassles with different crankshafts, I always tell people to get a virgin engine if they can, as its never been monkeyed with.
vic,,,,, food for thought,,, I see them in the bone yrds here real often??? Wished I could send you one. dratzzz

When I tore down the seized engine and took it to the shop, it needed .060 to clean the cylinders of pitting... shop told me it still needs a final hone. Pistons, rings, crank service and bearings are all I need to get started on the green engine. The shop did quote me on the necessary pistons, but the cost per cylinder is like $25... quite high when the eBay ones are less than $10.

Heck, replacing my carburetor for $200 hurt like hell, but I finally got the dang van running this morning! Just gotta recheck the rocker clearance, tweak the carb and button it all up. Some stuff for these engines are not cheap up here. I think my options would be easier if I has a seventies 300, but I'm sooo scared of buying stuff for these two engines if the block and crank design changed so quickly (like a couple years of configurations like mine, and then decades for the new style), kind of needle-in-haystack stuff.

The last couple times I was out to the boneyards around here, I was surrounded by V blocks and four-bangers. Now, with my van running again, I wanna go trolling the boneyard to see what's out there. My friend actually is trying to sell a credit she has at one when she refunded a faulty alternator... it would be cool if I could find a newer FI rig out there!

Just a thought... what if I wanted to put a big six into my 62, knowing I need a late crossmember, is there a big six version of the 3.03 three-on-the-tree?