TwoLousGarage Posted January 10 Share Posted January 10 Hi all, I got my replacement ‘38 engine painted in the correct color green and am getting ready to install it in my ‘38 coupe. I noticed the head was only provisioned for the later 2 bolt valve cover and then researched the part number to reveal it’s a ‘51 263 head. The block decodes to a ‘38 model. My question: Will I have any other issues running this engine as is besides the valve cover bolt differences? This engine came with my car as a replacement for the original. It looks like it was fully rebuilt and run at one point, but does have 1 bent pushrod which is making me question its viability. Thanks! Link to comment Share on other sites More sharing options...
DonMicheletti Posted January 10 Share Posted January 10 If the rockers are not oriented on the shaft correctly you will bend pushrods because the holes in the head ill not allow the rods to match the rockers correctly 2 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 10 Author Share Posted January 10 49 minutes ago, DonMicheletti said: If the rockers are not oriented on the shaft correctly you will bend pushrods because the holes in the head ill not allow the rods to match the rockers correctly Is there a certain process to ensure that they are oriented correctly? The rocker is currently just placed on there with a few threads started in each bolt. I need to remove it to replace the bent rod anyway Link to comment Share on other sites More sharing options...
buick looks fine for 39 Posted January 10 Share Posted January 10 I agree with Don, and the 38 shop manual has a picture of the correct rocker arm sequence. Also I'm intrigued by your head. It definitely has a later type thermostat housing but the water pump shouldn't work. Check to see if there are any missing or missaligned bolts on the water pump. I tried to check the head part number but my parts book didn't cover that time span. Link to comment Share on other sites More sharing options...
EmTee Posted January 10 Share Posted January 10 The rocker arms do not look like they're installed on the shaft properly. Both the pushrod and valve ends do not align. As Don and Leif said above, the shop manual identifies how they are supposed to be installed on the shaft. This doesn't bode well for the rest of the engine 'rebuild'... I would pull the oil pan and check everything. Perhaps pull a rod and main cap and use Plastiguage to verify clearances. Also, once the rocker arm assembly is sorted, I would verify the TDC mark on the flywheel and roll the motor through the firing order to check valve timing. If there's any doubt, pull the balancer and remove the timing cover to verify cam timing. The proper crank/cam timing mark alignment isn't intuitive for anyone not familiar with these engines. Again, refer to the shop manual for proper timing set alignment. 4 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 10 Author Share Posted January 10 I’ll get some better pics this afternoon if the WP and rocker. The rocker is not currently bolted down, just has a few bolts started 1 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 10 Author Share Posted January 10 Photo of the water pump and rocker shaft. Rocker arms clearly don’t align consistently even though they are only partially bolted down. What are the groups thoughts on that water pump? Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted January 10 Share Posted January 10 I don't know about the water pump but the rocker arms do appear to be installed wrong. They must be assembled on the shaft in a certain order. Ben 2 Link to comment Share on other sites More sharing options...
pont35cpe Posted January 10 Share Posted January 10 Not sure if a 263 rocker assembly is different, but here is on for sale. https://www.ebay.com/itm/374092975858 1 Link to comment Share on other sites More sharing options...
buick looks fine for 39 Posted January 10 Share Posted January 10 I agree with EmTee. You might consider finding a 38 head and cannibalizing the 263 head. A 39-40 248 head will work but they have 2 bolts for the valve cover not 3. Also the water pump looks jacked, the inlet for the thermostat housing should be vertical and not at an angle. The mating surfaces between the water pump and block might also be wrong and you don't want to restrict water flow Thanks Leif 1 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 10 Author Share Posted January 10 This info is invaluable for a 28 year old trying to revive an old coupe with his dad. So let me first say THANK YOU for the quick and informative replies. So I have the original engine out of the car that is frozen solid. My parts book shows the part number on this head to be for 1940-1945 (1302277), but it has 3 valve cover studs. It also doesn’t have the same paint as the block so I imagine it was swapped at some point. Can I swap this head onto my “new” 38 engine after cleaning it up and making sure the valves are good? 1 Link to comment Share on other sites More sharing options...
DonMicheletti Posted January 10 Share Posted January 10 There is a lot of head swapping that is OK on the straight 8's. The cover studs dont mean a thing. If you can find old issues (online) of the original Torque Tube (TT) magazine, head swapping is discussed at length and is very informative. Maybe some of the other posters can help on finding the old TT's 1 Link to comment Share on other sites More sharing options...
Rock10 Posted January 10 Share Posted January 10 The rocker arms angle slightly to the left and right. Your new one seems out of wack. Check with the old one to see. They are fairly easy to take apart and reorder. 2 Link to comment Share on other sites More sharing options...
Rock10 Posted January 10 Share Posted January 10 And you will get tons of excellent advice here. I know I have. 1 Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted January 10 Share Posted January 10 As Rock said! It is not a difficult job to dis assemble and re assemble the rocker arms. If you have a Buick Shop Manual it is detailed therein. I believe the last head you show is for the '37. Ben 1 Link to comment Share on other sites More sharing options...
pont35cpe Posted January 10 Share Posted January 10 (edited) TwoLous, another little tidbit.. Once you get the rocker assembly lined up correctly, and bolt it to the head, be sure to seal the threads of the short bolts, of the 8 towers. If not sealed, eventually oil will weep down the threads, and oil will puddle around the spark plugs. And tower #8 has a stud/nut in place of a short bolt, a bolt would interfere/damage the temperature gauge bulb. Is that a Florida Gators hat in the background? Edited January 10 by pont35cpe (see edit history) 2 Link to comment Share on other sites More sharing options...
EmTee Posted January 10 Share Posted January 10 The thermostat housing looks wrong. Maybe that's original to the head (i.e., later than '38). Can you swap the thermostat housing from the original engine? From what I can see, the thermostat housing on the original engine looks correct. 1 Link to comment Share on other sites More sharing options...
Daves1940Buick56S Posted January 10 Share Posted January 10 Iirc the rockers should toe in. Somebody assembled them toe out. Swap each one left to right. One would think a shop would have caught that. 1 Link to comment Share on other sites More sharing options...
EmTee Posted January 10 Share Posted January 10 The bad news is even when the orientations are corrected, the rocker arms are probably not where they were originally. That means they're going to have to wear-in again to become 'comfortable' in their new locations... 3 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 11 Author Share Posted January 11 (edited) So I read through the shop manual and think I can handle getting the rocker assembly right. Both water pumps have the same part number (1307344). It’s strange they capped off the “new” engine WP. Perhaps I can just swap the thermostat housing and be ok? Also- all the work benches are filled with various 72 GS 455 Convertible side projects. So I used the GS as today’s work bench. Edited January 11 by TwoLousGarage Wrong jnfo (see edit history) 1 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 11 Author Share Posted January 11 3 hours ago, pont35cpe said: TwoLous, another little tidbit.. Once you get the rocker assembly lined up correctly, and bolt it to the head, be sure to seal the threads of the short bolts, of the 8 towers. If not sealed, eventually oil will weep down the threads, and oil will puddle around the spark plugs. And tower #8 has a stud/nut in place of a short bolt, a bolt would interfere/damage the temperature gauge bulb. Is that a Florida Gators hat in the background? Thanks for this! No gators hat here, I think you see a welding mask in the background next to my Philadelphia eagles hat. 1 Link to comment Share on other sites More sharing options...
pont35cpe Posted January 11 Share Posted January 11 Gotcha, that is a wild looking welding helmet. Link to comment Share on other sites More sharing options...
MCHinson Posted January 11 Share Posted January 11 6 hours ago, DonMicheletti said: There is a lot of head swapping that is OK on the straight 8's. The cover studs dont mean a thing. If you can find old issues (online) of the original Torque Tube (TT) magazine, head swapping is discussed at length and is very informative. Maybe some of the other posters can help on finding the old TT's The Link to the old Torque Tube magazines is on the 36-38 Buick Club website. On the home page, scroll down for the red Torque Tube Link. http://www.3638buickclub.org/ I have not searched the issues for anything about this subject, but they are all accessible there. The first document is an index of all of the issues. Link to comment Share on other sites More sharing options...
EmTee Posted January 11 Share Posted January 11 These look like the right pieces to assemble for your car: The coolant bypass should not simply be blocked-off, as it will cause wild internal temperature variations as the thermostat opens and closes. However, DO modify the bypass valve to lock the valve in the 'closed' position. When the valve is closed, there is still a space around the circumference that allows for some coolant flow when the thermostat is closed. I modified my valve by installing a length of copper tubing inside the spring that locks the valve in place. At a glance, the assembly looks normal, but the tube holds the valve so that it can't move. Read the Cooling System description in the shop manual (Chapter 6, I think) and it describes how the bypass was intended to work. Problem is the 80 year old spring gets weak, allowing too much coolant to bypass the radiator when the engine is hot. As long as the "equivalent 1/2-inch hole" is preserved (as described in the shop manual), the cooling system will allow for proper coolant flow when the thermostat is closed, with the minimum bypass after warmup. 1 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 11 Author Share Posted January 11 Today’s update: I took the housing off the 51 head to compare with my original. That’s going to be a no go. I’m going to bite the bullet and get the early head rebuilt. My NEW question: Can I harvest the valve springs and valves from the 51 head to reuse on the 37-40 head? Bob’s lists the intake/exh valves as 34-52, and springs as 36-52. I can compare after disassembly, but figured I would ask first. It sure would be nice to save $300+ Newest batch of photos for your viewing pleasure. The old ‘38 248 has seen better days. I believe it to be original to the car… 2 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 11 Author Share Posted January 11 Additional photos: 1 Link to comment Share on other sites More sharing options...
DonMicheletti Posted January 11 Share Posted January 11 Boy, that must have really been an oil burner! I think the spring re-use would be OK. Valve reuse would depend on head diameter differenceand length and valve stem condition and wear. If you go with new guides, Id replace the valves too. . These are not race car engines. 2 1 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 11 Author Share Posted January 11 9 minutes ago, DonMicheletti said: Boy, that must have really been an oil burner! I think the spring re-use would be OK. Valve reuse would depend on head diameter differenceand length and valve stem condition and wear. If you go with new guides, Id replace the valves too. . These are not race car engines. Last inspection sticker on the car is 1971.. my other projects weren’t even in production then! 1 Link to comment Share on other sites More sharing options...
drhach Posted January 12 Share Posted January 12 18 hours ago, TwoLousGarage said: Last inspection sticker on the car is 1971.. my other projects weren’t even in production then! Neither were you 1 1 Link to comment Share on other sites More sharing options...
Morgan Wright Posted January 20 Share Posted January 20 (edited) I don't know if the 263 head fits on a 248, but I do know that if the 263 came off a car with a Dynaflow it would be different than a standard, but I think maybe it's just the head gasket itself that's different. The head gasket specified for the DynaFlo is thinner, to increase the compression (and horsepower) a little. As for whether the head fits, the 263 has the same stroke but a slightly bigger bore than the 248. http://www.carnut.com/specs/gen/buick50.html That means the bore in the underside of the head would be bigger than the bore in the block, I really have no clue if it would fit. Edited January 20 by Morgan Wright (see edit history) 1 Link to comment Share on other sites More sharing options...
TwoLousGarage Posted January 25 Author Share Posted January 25 Thanks Morgan. We have the old 248 head scheduled to be dropped off at the machine shop Monday. It just makes the most sense to do right by the car and get the correct head on the replacement 38 block. We are hopeful we can swap the valves and springs over, but will order new if needed. I started cleaning the old rocker assembly and have cleaned every pushrod I have in stock. 3 Link to comment Share on other sites More sharing options...
EmTee Posted January 25 Share Posted January 25 I suggest that you carefully compare the pushrods to ensure they are all the same length and are not too worn or damaged. 2 Link to comment Share on other sites More sharing options...
danhar1960 Posted January 26 Share Posted January 26 Check that your rocker shaft isn't packed with old oil crud and all the feed holes to the rockers are clean an clear before installing it. Just washing the outside doesn't get the crud from inside the shaft. Also check the wire mesh screen in the oil feed line is not caked up with old oil crud. Danny 3 Link to comment Share on other sites More sharing options...
Rock10 Posted January 26 Share Posted January 26 Yes. Ours was packed solid with nasty, crusty stuff. Link to comment Share on other sites More sharing options...
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