Bloo

Maybe there's a different sensor but I doubt it. This is pointing strongly to a problem with the gauge itself.

No. In some cases the pump itself might need to be wet to work though. This is undesirable and is caused by check valves that don't seal very well. If the pump can pump, it will fill the line to the carb.

The fuel is probably just evaporating. Once the fuel is pushed into the carburetor bowl, there's no way for it to escape back through the fuel pump.

This back plate looks really nice. It might be worth having, as long as it's not full of Bondo or something.

On a closer look you might have to make gaskets. It looks like the bypass hole is not there, but it also looks like there's another port below the mounting bolt by the hose. I don't know what that one is for. I don't think the gasket in the pics will seal it. I made gasket patterns for the Pontiac and then cut my own from the patterns. It's all in the thread. I don't know if I could have bought them, maybe, but Best Gasket's 37-up Pontiac gaskets are all over Ebay, and not a sign of any 33-36. Like Olds, 37 was a change. As previously mentioned, if anyone has them Olson's would.

The back plate is notched. See your earlier picture. If the gasket is like the one you posted earlier, the hole is rather large and out of the way. I believe you are on the right track.

Typically having no vacuum on that port would cause it to run super rich all the time except high speed full throttle. I doubt it could have run well.

Is the fuel gauge accurate? What happens if you disconnect the wire at the temp sensor? The little flasher can thingie affects both gauges. If one gauge is OK, it is probably OK. I believe the little can should be "on" about 50% of the time. If the fuel gauge is accurate, we can probably rule out the little can. Gauges are thermal so always rise slowly. It does sound like a shorted wire, but if you have tried another wire I guess not. If the temp gauge goes all the way down when you disconnect the wire, It is probably fine. I have the ohms measurements in a book somewhere but I can't get to it. I just found in an old forum posting that a Ford sender (with this type of system) is 75 ohms cold and 10 ohms hot. I can't verify. I believe you could check sending unit ohms at room temp (cold engine) on any other 60s or early 70s Ford you might have available that has a factory temp gauge (not a light) and it should be very close to the same. It wont be exact though. The tolerance is a bit loose. Measure from the sending unit post to the block with the wire disconnected. Best guess is the new temp sensor is bad, but I would measure it at room temp and compare to another Ford. If they are close to each other, then the gauge itself is probably bad. Before condemning the gauge, make sure it is getting it's 50%-ish interrupted power from the little can like the gas gauge does. If the temp gauge is running on pure 12 volts, that could cause your trouble. I doubt you would get any satisfaction by adding resistors. You could bring down the gauge that way for sure, but the amount of swing per degree could easily be way off. It's hard to predict. It might be OK and it might be a mess. Better to find the actual problem. One last thought: Are the engine and body grounded together? Welcome to the forum!

It's *probably* a critical vacuum signal for enrichment control, and *probably* used a gasket about like this to connect the vacuum signal originally. I even think I see it in the rust shadow on your friend's carburetor. @carbking will know for sure.

Take a good close look. A poor connection will do that. It's possible they cooked it from the inside. The rockers are probably worn too, not that I think it makes much difference, but it does affect preload. At least check the preload when you assemble. Don't soak your lifters because that makes it too tough to do. Ford's instructions in the manual are bad advice according to the guy who ground the cam, and he was probably correct because careful measurement of my original parts (1970 390-2V) revealed Ford wasn't following those instructions either when they built it. Not even close. If I remember correctly he told me to shoot for .030-.060. Tighter is OK if necessary, but you wouldn't want to be looser for obvious reasons.

Some ideas, sort of in reverse order. #4 is where the trouble probably lies. 1) Is it moving the diaphragm? The way this works is not quite what it seems. The arm follows the cam inside the engine, but the diaphragm does not necessarily follow the arm. There is typically a spring that keeps that arm following the cam but that's all it does. The arm LIFTS the diaphragm, but that is all. The big coil spring pushes the diaphragm down all by itself, and diaphragm doesn't come back down at all if the float valve in the carburetor is closed. As soon as the float valve in the carburetor opens, the big coil spring and the diaphragm start pushing fuel again. The big coil spring is the main part that determines fuel pressure. 2) Is it moving the diaphragm enough? It is hard to find a spec for how much the diaphragm moves, but sometimes it comes in the rebuild directions. Sometime you have to guess. A worn out fuel cam inside the engine is what you are looking for if you test this. I've done it by attaching one side of the housing with the diaphragm attached at the stem but flopping in the breeze, and cranking with the ignition disabled. As an example my 36 Pontiac pump had about 0.25" if I remember correctly. Maybe slightly less. It is a small pump so that seems reasonable. A huge pump with a larger diaphragm is probably designed to move more than that. 3) Speaking of diaphragms, you want quite a bit of "pull" on the diaphragm when you tighten the screws so you aren't limiting the motion by having the diaphragm stretched too tight at the ends of travel. This has more to do with long diaphragm life and won't keep it from pumping. 4) And now the check valves. If they leak you are going to have a bad time. I would start by connecting a vacuum gauge to the fuel inlet and pumping the FUEL pump by hand. A mityvac with it's gauge will be fine, you'll need one anyway. The pump should be able to create quite a bit of vacuum and hold it. It wont hold it forever, but definitely should not leak right down. If it won't make or hold any vacuum, you have a problem. To get good pumping both check valves must seal. In the old days there was an unwritten rule to NEVER mess with a check valve that seals good. Good advice then, but now the fuel has ethanol in it, and if there is any rubber or rubberlike parts in a check valve, you must use the new parts. If the check valves are hard phenolic it's probably best to leave them alone just like in the old days if they work, or at most change the little springs. One valve is easy to test. Connect a mityvac to the fuel inlet (where the tank line normally connects). An el-cheapo mityvac copy from Harbor Freight will do fine. Suck up some vacuum. if it won't hold any vacuum do whatever it takes to get the check valve sealing. It won't hold forever, but shouldn't leak right down. The other check valve needs to seal too. Testing that one is tougher. You have to figure out how to rig something to suck on it with the mityvac from INSIDE the pump body. Both of these valves let fuel flow toward the carburetor but not back. That's why the first one is easy and the second one is tough.

Pontiac and Ford have the wrong valve order. Both have a 4 branch intake manifold. The wildly underrated Ford has a separate port for every intake valve. The Pontiac has the two inner branches of the intake manifold feeding siamese ports.

4.44 is typical of prewar Buick Specials.

I would be kind of surprised if the gasket kit fits. Maybe? That is another parts book question. I guess if the pump will bolt on it is possible. In fact, the rust pattern on the front of your block looks like it might have been using that same gasket on the block side on your car. I can't imagine using some pump that won't quite fit, especially when you have one that does. If it is the modern bearing you want, I would keep looking. Pontiac made backdated water pumps for their earlier engine with modern guts. I am using one right now (but I am changing back when I get the authentic one assembled). Buick did too. I believe the aftermarket made backdated pumps for Pontiacs and Buicks too. I would be extremely surprised if backdated pumps do not exist for Oldsmobile. If a modern bearing pump is what you are wanting, keep watching ebay. If I were you, I would use that pump you have, or the one in the third set of pictures. If I were guessing whether the later water tube might work, well... you are on the right track. If the headgasket is the same as 37-up, the chances are good. The other thing to look at is the number of intake ports/runners on the intake manifold. If the head gasket and the manifold branching is the same, it's almost a slam dunk that the later tube could be modified to work. If the headgasket is not the same, but the head length is the same and the manifold branching is the same. that is still promising. If the chances look good I would just buy a later one and compare. In fact, that is what I did with the Pontiac. To be completely clear, what would make the chances really good is if the valve locations in your block are the same as the redesigned 1937 engine, because the water tube probably squirts under the exhaust valve seats. Example, a Mopar six has 3 branches on the intake manifold, and the exhaust manifold goes to the far ends of the engine. The valve order has to be E-I-I-E-E-I-I-E-E-I-I-E. A Pontiac six on the other hand has four intake branches, and the exhaust manifold also goes to the far ends. It has to be E-I-E-I-I-E-E-I-I-E-I-E or E-I-I-E-I-E-E-I-E-I-I-E. I'm pretty sure Pontiac is the former, but it has to be one of those. It can't be like the Mopar because there is an intake manifold branch in the center of the block on the Mopar, and an exhaust branch in the center of the block on the Pontiac. A comparison like the one above on 36 Olds vs 37 Olds combined with head or head gasket spacing would tell you if the exhaust valves were in the same spot in the later engine. That might already be the later tube in your car. It doesn't appear to fit well, though that doesn't prove anything. I couldn't find a picture of a 36 Olds tube anywhere. It would sure be useful to see one.

In my opinion, the odds are against it being OK. If I was in as far as you are, there is no way I would put it back together without knowing. It looks like my guess about the hole was right. I see two clean pumps after yours. The middle one has a hole up high for bypass, and assuming it would even bolt to the block, the hole would be up high and just squirt water on the ground. As I recall, that hole connects to a hole in the head of the later Olds engine and a special grommet seals it all up. A year or two ago someone in the forum was looking for that grommet. I don't know if he was ever able to source any. I think I see a drain hole on this pump implying a modern style bearing and seal (as several makes would have used from 1938 forward, I am unsure exactly when Oldsmobile made the switch). The fan hub and shaft still look like something from a packing pump, but that might be an illusion. It's a shame they didn't show it from the top. The last clean pump looks like another pump for an earlier engine, maybe like yours. The hole is down low, and I think I see the "bowl" structure in the nose that would imply a pump with oil cups. It's kind of hard to tell. I think the pump you already have is the one you need. If there's nothing wrong, I would fill the oil cups up with turbine oil (zoom spout) or 10w motor oil and let it soak some up. I might take the back plate off, make it a new gasket, and see how close the impeller clearance at the front of the blades is. I've not seen a spec, for 1936 Olds, and I doubt it is super critical, but I don't think I would want .080 or .100 for instance, that would probably be too much. Discount endplay if you check this, as the impeller should pull all the way forward against the thrust surface in use. As for the endplay itself, there's probably a spec in the shop manual. I have looked at a lot of Oldsmobile rebuild kits since some of the parts look suspiciously like Pontiac, and one thing I have noticed is Oldsmobile (and LaSalle) had a stepped shaft on some models, maybe all(?) in 1936, but not 1935. Pontiac went to a needle bearing in front halfway through 1936 to increase durability. I believe 1936 Oldsmobile went to a stepped shaft and a larger front bushing for the same reason. If this is correct, you may find a larger bore for the bushing in the front of a 1936 pump compared to 1935. It is probably unique to that 1936 and earlier engine. I have seen the crescent shaped ones on ebay that were for Oldsmobiles newer than yours. The shape of the outlet hole in the back of your pump is not crescent shaped like that. It's closer to Pontiac's weird trapezoid, but not really the same as Pontiac either. I must admit not looking that close at Olds water tubes I saw in the past. Pontiacs, which I would be looking for a substitute for, are a 10 port block. Is yours? I thought not, but reviewing the pictures of the parts ramair had for sale until recently I am not so sure. If it's a 10 port block, with 4 legs on the intake manifold, the valve order is wrong compared to Mopar. Since the tube is supposed to squirt on exhaust valve seats, there was no way one of those Mopar tubes was going to line up on a Pontiac. I doubt Mopar would just fit Olds but you never know. A direct comparison would be needed. You should know the Mopar sixes come in two lengths, with heads either 23" or 25" long. I can't help but wonder if the 37 Olds tube could be close enough to modify. There's some of those on Ebay. I have no way to look that up. You are for sure going to need a parts book. I imagine they are hens teeth for Oldsmobile, so good luck.....

If you were able to take the radiator out, you are already way ahead of where I was on the Pontiac. Good luck with it. 👍

Miles per GALLON of oil chart from a 1936 Pontiac shop manual. What was considered normal in the prewar era might shock you. There was nothing particularly unusual about this. Postwar overhauls with modern piston rings, or better yet modern pistons and rings did much better. Take a good close look.....

Some cases? Nearly all. Craftsman is not what it was. It's a lot of gimmick tools. If you look around be a little choosy, you can *definitely* do better at Harbor Freight. You can usually do better with Home Depot and Lowe's house brands too (like Kobalt, etc.). As for the old Craftsman, I wouldn't turn it in.

Read my Pontiac cooling system thread and all will become clear. The parts do not interchange, but the design is nearly identical. This isn't just Oldsmobile and Pontiac. It also applies to Chrysler products, junior Packards, Grahams, and probably a bunch of others. No picture showing that? I can't even tell from those pics what kind of bushings or bearings it has or whether it has a packing nut. From your description I'm guessing it has a packing nut and is probably original. The hole is the bypass that allows the thermostat enough flow to function without trying to boil the back of the engine first. There have been detailed threads in the Buick section about how this works, but I don't know how to find my way back there offhand. Buicks had a spring loaded valve that the factory advocated replacing with a hole later on. Being overhead valve, the Buick stuff looks very different but functions the same. I have seen a reference to soldering up a hole on an Oldsmobile water pump somewhere too. My best guess is that the hole on a 37 pump does not land in the right place on the earlier engine and would just squirt water. A bypass of some kind is almost necessary, and considering you have a hole in your block that lines up with the plate, I am guessing that is all correct. The fan thing may be a red herring. Around 1937-38, Chevrolet had some water pump changes that required updating the fan due to flange height issues. I've seen clues that something similar happened at Pontiac in 1937 or 1938, but no proof so far. In any event, the most likely reason to change a fan was it did not fit anymore after a water pump update. The internal construction of many automakers water pumps changed from bushings and packing to cartridge ball bearings and carbon seals in the 1936-38 period. That can have a large impact on the length of the nose of the pump, and perhaps more importantly, shaft diameter.

That looks like a piece of the ball separator for a ball bearing.

You mean the one in the center, don't you? The one the front doors hang on in a 1935? To the best of my knowledge no one makes a kit. If anyone still did, I think it would be KC. Fisher made the wood first and put the metal skin on after. A guy I met with a 35 Pontiac sedan (that post is almost identical) made 3 pieces, one to fit in the front of the post (facing the front of the car), one to fit the rear, and a piece with flat sides to fit in the middle. He then glued it all together inside the post. There are people on this forum who can make custom wood, but they will need to have the whole body present in order for it to fit right.

I don't know, but SAE 140 oil in place of SAE 160 didn't do that. Lots of people have made that substitution. I believe you are correct that SAE 250 is closer to SAE 160 than SAE 140 is. I just don't believe you could have hurt it with that substitution. Maybe some bushing or thrust washer is getting ground up in there. Maybe not. What bothers me is that unexplained noise you said it was making. Synchros are literally friction devices, brakes. They have to cut through and remove the oil film to work. I have been using Redline 75W140NS in the Pontiac. Original was SAE 160. Any wear is going to show up as flakes. If it's minimal, and most of that brass color is really just an oil/water emulsion, maybe there is no big problem. The only reasons I can think of to want super thick oil in a synchromesh transmission are gear noise and or leakage. If the gears were designed around thick oil, they might have too much lash to run quiet in thinner oil. My take is the synchros would be much happier in something really light, like some synchromesh oil, lightweight tractor oil, or motor oil. Basically any oil that does NOT have extreme pressure additives in it, and the lighter the better within reason. The synchros are probably huge if they were meant to run in SAE 160. They had to scrape it off to stop the gears. If you manage to protect them so well that the brass doesn't wear at all, the gears will just grind. When gear oil attacks brass chemically, I believe it turns the brass dark, so that probably didn't happen either.

You didn't do anything bad to the synchros by running thin oil. You could run thinner oil and the synchros would probably love it.

What on earth am I looking at? Is it a water/oil emulsion? Is it metal? What was the "wrong" oil? If that's metal, something is really wrong.

Well, I didn't get that out of it at all. Are you sure we read the same post? I don't see any hate for those who choose to hire things out, just maybe a little side eye for those who failed at something and never got back on the horse. That's not the same thing at all. I agree there's room for all of us in here. 👍 In my own experience, in any given year, there will be a short list of people or shops to whom I can hire out specific jobs, and trust things to go well and the job to be done correctly to a high standard. Probably all of us have a list like that whether we wrote it down or not. If something I need does not fall on that list, and I just have to pick someone... well.... things don't turn out acceptably more than half the time. I do a lot of stuff myself, and often take on things I haven't done before so I don't have to be in that situation. I don't judge or look down on people for hiring things out. I cringe in silence because I want it to go well for them and I think the odds are against a good result. If it turns out OK I breathe a sigh of relief. I also agree with skidplate anyone can learn this stuff and improve over time if they want to, and there is no requirement to be "mechanically inclined". I think that is a myth like "musically inclined" when the reality is hours and hours of practice.