Have a GMC p/u with 54 Chevy 235 hydraulic lifter engine that can't be rebuilt (was .80 over last rebuild). Bought complete 235 truck engine w/ head casting # -848, year unknown, but found head is cracked and not usable. The head gasket from newer truck engine lines up w/ all the holes in the car engine head - anyone know if it will work?
The same heads were used typically on 235s for car and truck service, with some variations depending on model year. What is the casting number of the head you are looking to use? And what is the date code on the engine block (raised letter-number sequence sort of behind and above the starter)?
OK, those numbers from the head look like they are from the passenger side - they don't help. The casting number that IDs the head is on the driver's side, forward of the carburetor, over one of the exhaust ports. Very easy to see and will be 7 digits long. First photo shows where to look (red arrow), and the second photo is an example of the head casting number (this one from a '54 235).
The J suffix in the engine serial number IDs the block as a later 235, a Thriftmaster engine for truck service, as you know. Would need the date code (raised cast letter/numbers from near the starter) to date the block more precisely. The third photo shows an example of the date code, and where it is on the 235s (red arrow). For this example, F decodes to June, 7 is the day of the month, and 4 decodes to 1954.
Hope this helps... a bit more to confirm the head specifics, but I should have said yesterday, it will probably work.
I just took the head to shop for magnaflux to make sure its good - engine ran well until oil passage plugged up and spun rod bearing. Will post head number when I get it back.
All 1953-62 235 heads will interchange, there is a slight difference in compression ratio on some. 1953 is not drilled for the four bolt valve cover, and 1956 and later have a larger hole for the temperature sender, but there is a common adapter made for that if you are using a mechanical gauge.
A cracked head is not necessarily junk, it's just that most machine shops these days lack the skill or the work ethic to repair cracks. Mostly, they're just too lazy. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
PJ, what's the casting number on the head you want to consider running, not the one that was on the truck engine? BTW, 848 heads are fairly common, were used on cars and trucks '56-'62, and not too hard to find.
The code you posted for the 235 truck block dates it as a November 5, '61 block. Good starting point.
Never believe me, but I always thought that if the block and head had the same number of bolt holes (15 or 18), they would work....with the 848 caveat. Like drilling holes in my 848 head for coolant circulation to match what's in my 261. The 18 bolt pattern is the same.
34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
I think you can use any 18 bolt 235 head on a 261, not just the later/common "848" higher compression heads".
All of those 235 heads should have the 6 extra coolant passages drilled in them (at a slight angle, I recall - maybe someone will post a link to that drilling procedure/instructions?).
34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
The other thing you want to be cognizant of is the rocker assembly your are using. If your block is a 59 or later block, those blocks had a slightly different oil supply system to the head, more of a pressurized higher volume system. The block had a larger orifice then did the earlier blocks, the connector tube on the rockers was pinched off, and rockers had the groove to supply the oil dribble hole off set. The 55-58 blocks used a small orifice and the grove for the dibble hole in the rocker arms directly intersected the dribble hole. So if you use a 59 and up block, and the 55-58 rockers, you will likely get too much oil to the rockers, actually spitting over the rockers. So generally you want to use the rockers that match the block.
That being said, this is where the famed drilled head bolt and plug come into play. The bolt and plug arrangement restrict and redirect the oil flow to the head from a later 59 and up block so you can use the 55-58 rockers.
All that being said, if the 59 and up motor has some miles on it, the oil to the rockers may already be compromised just from increasing clearances in the motor due to normal wear and tear so using the 55-58 rockers might work. Its all about the dribble. No spitting, the rockers need to dribble.
I was going to post a picture of my 261 head with the holes drilled but Tim's link has a good picture. If I understand it correctly when I did mine the angle is so the hole you drill is directly in the water jacket and not just half way.....to put it in simple terms!
Got '54 car engine head back from shop - told it has cracks in 2 combustion chambers. Engine ran OK before oiling prob stopped it, did not do compression test tho. The '61 truck engine head had prior crack repair that failed, machinist said its very hard to do it right and would be very expensive if I can find someone who does this.
I guess they do things differently out there than we do in Tennessee! Or maybe stuff that was routine 50-something years ago is too difficult these days! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Sorry to hear that, PJ. "It will be expensive" is a tip off the shop doesn't want to deal with it, of course. Anyway, '848 heads aren't that hard to come by. Try putting a "parts-wanted" post in the Truck Parts Wanted section of the Swap Meet forum of this group? That should turn up some candidates for you.
If that doesn't work out for some reason, James at JJ Inlines usually has '848 heads available, and he will supply magnafluxed parts (or fully rebuilt with warranty) if requested, although he's not cheap (but he does ship for a reasonable freight charge). His website only lists a fraction of what he has, so direct contact recommended. James responds best to email.
I'm having the same sort of issue with a machinist who really doesn't want to grind a crankshaft my way. That's one of the big reasons I went ahead and bought a grinder for my own shop. I did find an old geezer (2 years older than me) who agreed to grind a prototype shaft to my specifications for half what the other guy wanted. That will allow me to get a dyno test engine assembled while the equipment and power wiring is getting rearranged in my shop for several pieces of equipment that require 3 phase power. Once that's done, I will be able to modify crankshafts, cylinder heads, and blocks without relying on anyone else to "do it my way"! Frank Sinatra was not the only guy who ever believed in that principle! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
some time ago there was a shop here in Spartanburg that specialized in repairing diesel engine heads but not sure if they are still in business. perhaps check some diesel shops in your area. I understand head repair like this was common...........back in the day, maybe still is??
It's usually reserved for big commercial engines that replacement parts tend to be extremely expensive- - - - -patching up an automobile block or head is usually prohibitively expensive unless the part is extremely scarce. The machine shop where I ran the connecting rod reconditioning department sort of specialized in commercial Diesels, and they sublet their crack repairs to a company called "Diesel Cast Welding". The technology exists, and has actually improved over the past few decades, but it comes at a price that will make your checkbook need CPR! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
