philipj Posted March 5, 2023 Share Posted March 5, 2023 (edited) Would anyone know the original part number for the head bolts on a 1936 Oldsmobile F36? It would also be beneficial to have the bolts specifications to source new ones if originals cannot be found... On the other hand, would it be beneficial to use studs instead of bolts to minimize stress on the cylinder block? Edited March 5, 2023 by philipj (see edit history) Link to comment Share on other sites More sharing options...
GARY F Posted March 5, 2023 Share Posted March 5, 2023 If you have a sample of one take it to Fasinal .I bought all new ones from them for my L-37 Olds. Link to comment Share on other sites More sharing options...
philipj Posted March 5, 2023 Author Share Posted March 5, 2023 (edited) No, I do not have a sample yet, and also waiting for a parts book, so my hands are tied... Just trying to find some things I need before I receive the vehicle so I can get to work on it ASAP... If you study the photo you can see that: a) there is a problem with the head gasket b) the wrong horn is installed, and may be part of the problem c) missing two of the correct bolts plus the correct horn bracket or horn? d) the incorrect coil is also fitted... e) damaged fan blade? water pump reseal is also questionable... So many wrongs can come out of just one photo! Edited March 5, 2023 by philipj (see edit history) Link to comment Share on other sites More sharing options...
Bloo Posted March 6, 2023 Share Posted March 6, 2023 (edited) I wouldn't necessarily replace the head bolts. condition is everything. If they are not damaged, I would leave them alone. Postwar metallurgy is better though. They will have modern markings and possible a different thickness of head. If you replace them get alloy steel, grade 8 or similar. Studs are better because you are not removing them every time the head comes off, so the threads in the block won't get damaged. They have one distinct disadvantage though, corrosion can and often does cause the head to get permanently stuck to the block. It's a real headache. I wouldn't use them on this. Are you sure that horn is wrong? I don't think this is the first time I saw something like that on on Oldsmobile. The horns themselves look a lot like the optional dual horns on my 36 Pontiac, except for the fact they are mounted to the engine, but an Oldsmobile does not have a "silver streak" between the halves of the hood to mount them to. I'm also looking for that coil and have been for years. Good luck. Store brand NORS shows up occasionally on ebay. Delco? Never. Some will tell you you shouldn't be running the original anyway and that they don't work well after all these years. I am going to keep the original setup until I am forced to change. Mine works fine but is physically damaged. I don't see any armored cable or metal cap hanging there, so there is probably more missing than just the coil. The armor ran all the way to the key switch, so chances are it is wrong too, or too hacked up to use the original way. If the fan is damaged, don't run it. I can't see that in the picture. If there's doubt about an original fan, get it magnafluxed. I need to do that too, but don't know where to go. I believe the water pump if original has a packing nut. I wouldn't condemn that off the bat. It should seep very slightly and is adjustable. If it has a modern seal, and this is quite likely as GM and others offered retrofits for older cars, it should not be leaking at all. Those are pretty easy to fix if you have a press and if nobody has hacked up the pump body. Kits show up on ebay, but inspect your internal parts and compare to a seller's pics carefully. There might be several versions. That 3-relay voltage regulator doesn't belong either, but might represent a worthwhile upgrade if the generator that goes along with it is there. Edited March 6, 2023 by Bloo (see edit history) Link to comment Share on other sites More sharing options...
philipj Posted March 6, 2023 Author Share Posted March 6, 2023 (edited) Hello Bloo, Thank you for your input here... You raise a good point, replace only what is needed, and very good observation about dealing with corrosion if you have to remove such a large head later on... As for the horn, if you look at the photo carefully you can see that the horn mount (at least) belongs to another car and someone used nuts under it to be able to make it work on this block... The next photo illustrates what seems to be the correct mount for it. I think that there are other coils that could work if you find the other small parts.... Something like this: https://www.bowtiebits.com/store/store_product_detail.cfm?Product_ID=5627&Category_ID=11&Sub_Category_ID=151 If someone went through the trouble of removing the armoured cable but left the original switch, you can rewire the switch... The challenge would be to find the armored material and re-attach to the switch. The only other part missing would be the cover that fits over the coil, where the armored cable threads into... and voilà you have something that looks period correct... Now why should we never be running original Delco coils with armored cables? I know that some cables short out. Condition is everything... Regarding the fan blade, it appears that it was bent as someone tried to spin the motor over... You cannot see it on that photo though. Will a 37 Pontiac blade fit that water pump? The water pump may be fine, my gripe is the way it was installed with gobs of silicone! I hated silicone in the 90's and I still do today... It is garbage and it does not belong in a prewar car... Lastly, should the generator be the type with a cutout relay on top? Similar to my 39 Chevrolet truck, which also has a special light switch through which you control the charging rate... Bummer, more stuff to change! Edited March 6, 2023 by philipj (see edit history) Link to comment Share on other sites More sharing options...
Bloo Posted March 6, 2023 Share Posted March 6, 2023 (edited) 3 hours ago, philipj said: As for the horn, if you look at the photo carefully you can see that the horn mount (at least) belongs to another car and someone used nuts under it to be able to make it work on this block... The next photo illustrates what seems to be the correct mount for it. I cant help but wonder if the bracket is just bolted on the horns backwards. Even if it is, you are still missing the front support bracket. My car has something similar, although it hangs from above, and I think it is important. There's a lot of horn hanging out there, and the metal is thin. 3 hours ago, philipj said: I think that there are other coils that could work if you find the other small parts.... Something like this: https://www.bowtiebits.com/store/store_product_detail.cfm?Product_ID=5627&Category_ID=11&Sub_Category_ID=151 Probably. Maybe not that exact stuff. It's similar. If I remember correctly the factory coil replacements for 36 Pontiac had a removable cup on the bottom of the coil where it engages the top cap, but the originals probably did not. Probably those were fixed. I believe these are in both cases the same coils as Oldsmobile, but I can't prove it as I have no Oldsmobile books that cover this period. 3 hours ago, philipj said: If someone went through the trouble of removing the armoured cable but left the original switch, you can rewire the switch... The challenge would be to find the armored material and re-attach to the switch. The only other part missing would be the cover that fits over the coil, where the armored cable threads into... and voilà you have something that looks period correct... My guess is if you don't have all of it, it would be easier to find another one. In Pontiac, that is all one piece, never meant to be taken apart. Chevrolet calls it "Electrolock" It's actually the second generation of Electrolock, the first version had the armored cable going to the distributor to short out the points. I don't believe Chevrolet ever advertised that there was a difference, but it is useful to know if you start Googling "Electrolock". Anyhow, I suspect the electrolock on a 36 Pontiac is the same as a 36 Oldsmobile because I have seen Oldsmobiles with the original coil still hanging, and its in the same spot. If the key is in the center of the dash on a 36 Oldsmobile, it it almost certain to be the same Electrolock. Again, I have no book to verify. A 36 Chevrolet Electrolock is different. They mounted the coil on the engine, and the armored cable is longer. The coil is almost right, but the mounting bracket is welded on, and in the wrong place. You wouldn't try to take it off. The bracket is pretty thick but the coil sides are paper thin. I think this is how some previous owner damaged the Pontiac coil that is on my car. When I bought the car, the coil was hanging loose in an incorrect bracket. If you do need to replace the wire inside the armored cable, you have to take the switch apart, and remove all the internals to get to the bottom where the wire is. The switch is staked together. Nothing about this sounds like fun, but it's doable. There are people on the VCCA forums you can hire to do it, or so I'm told. Mine still works with the original wire. The cap doesn't come off of the cable. That's kind of the point. It doesn't come of the coil easy, but can be released with a feeler gauge to remove the coil. In order to hide the cap and cable, they would have had to remove the switch, take it out through the engine compartment because the hole in the firewall is not big enough to go the other way, reassemble with the cap, cable and all inside the car under the dash, and then add a piece of wire to go through the firewall to the coil. You might find that. I'll bet you find a hacked up mess instead. I hope I'm wrong. 3 hours ago, philipj said: Now why should we never be running original Delco coils with armored cables? Supposedly there have been a lot of failures of coils of this age in more recent times. It's probably true. I am stubborn and am going to keep pushing my luck. Your mileage may vary. 3 hours ago, philipj said: Regarding the fan blade, it appears that it was bent as someone tried to spin me motor over... You cannot see it on that photo though. Will a 37 Pontiac fit that water pump? I doubt a Pontiac fan would fit but maybe? Don't try to run it if it turns out to be bent. 3 hours ago, philipj said: The water pump may be fine, my gripe is the way it was installed with gobs of silicone! I hated silicone in the 90's and I still do today... It is garbage and it does not belong in a prewar car... I agree completely The Olds pump is similar in construction to the Pontiac one. There's a flat plate on the back. It might be hot garbage. Someone may have gooped it up out of frustration. I have 2 33-36 Pontiac back plates. One came on a remanufactured pump and is rusted out beyond any reasonable use. The other one that came to me mounted on the car is sort of OK, but I discovered that there was erosion on the gasket surface that was not initially obvious. It was a pain to get sealed up. Paper gaskets and Indian Head weren't getting it done. The plate just wasn't flat enough. There are lots of things you could use though that don't leave silicone turds sticking out everywhere. Hylomar (blue) is the obvious one, but it's a little difficult to source. Permatex Anaerobic Sealer is probably what I used. Even some thick shelllac putty like Permatex #2 probably would have been fine. 3 hours ago, philipj said: Lastly, should the generator be the type with a cutout relay? Similar to my 39 Chevrolet truck, which also has a special light switch with a resistor through which you control the charging rate... Delco 936T generator and 5588 regulator, probably. I believe that is a small frame third brush generator, similar to a 1936 Pontiac generator, with a fixed third brush, an external field terminal, and meant to be used with a 2-relay voltage regulator (cutout and regulator, probably firewall mounted). Edited March 6, 2023 by Bloo (see edit history) Link to comment Share on other sites More sharing options...
philipj Posted March 7, 2023 Author Share Posted March 7, 2023 For all of you guys who are annoyed to see how one topic can deviate so much-have nothing to do with the title, here it is.... The original head bolts on a 36F were made of a chrome-nickel alloy, GM # 399872 or 7/16"-14 x 2 7/8" to be used with washers GM# 836819... Also unobtanium...;( Now if you can't find any originals you will have to go with a shorter grade 8 bolt (2-3/4") unless you get a 3" bolt and cut it... In my case, being that I have only 2 missing bolts, I think I will go with the shorter bolt and call it a day.... Interestingly enough, the workshop manual does not give you any torque specs for the head bolts, it only tells you "tighten cylinder head bolts in order shown in figures 3 and 4, drawing all bolts down evenly, repeating the operation until they're normally tight" then run the engine to normal temp and give them a final tightening... If I had to guess I would try to get at least 40-45 lbs across the head, anything more than that with something that old I think you risk breakage... One last thought, is a grade 8 carbon alloy steel stronger than a chrome nickel alloy? 1 Link to comment Share on other sites More sharing options...
Bloo Posted March 7, 2023 Share Posted March 7, 2023 (edited) I don't know. It is likely that grade 8 would be better in every way, but hard to say for sure. Steel making knowledge advanced rapidly during WW2. Torque wrenches weren't a common thing in the 30s, and most manuals don't list torque until 1941 or so. On some cars, you can just look in a newer book. That works on 1936 Pontiac, because the engine designs are so so similar from 1933 forward. On the Oldsmobile F Six though, 1937 appears to be a fairly major engine redesign. It appears to be more than just closing in the water jackets around the cylinders as many makes did around that time. Other things got moved on the side of the block and the overall look changed. If you could verify somehow that the head bolt size is the same on 1937 F as it is on 1936 F, I would just use a later Olds F torque spec from the 1940s. If by some chance the headgasket is the same, you could probably use a later torque sequence too. 40-45 lb-ft sounds low to me, but maybe you have smaller bolts than I do. Edited March 7, 2023 by Bloo (see edit history) Link to comment Share on other sites More sharing options...
philipj Posted March 7, 2023 Author Share Posted March 7, 2023 (edited) Hello Bloo, My new bible though incomplete, has some very useful information....;) It lists the same head gasket for 37-48, but not for the 35-36... As for the head bolts, GM# 399872 and washers, GM# 836819, they are the same! So, if I had a later workshop manual, I could find out what the torque specs for those bolts are... Furthermore, you are absolutely correct, 1937 is a major change in every respect for these cars... Besides the redesign and other technical improvements, in terms of parts, you now have parts kits or packages for the different groups which is nice... Nicer even if you could find those today; you can find a lot more stuff... I do see a big difference parts-wise... 37 and up seem plentiful compared to 35-36... Edited March 7, 2023 by philipj (see edit history) 1 Link to comment Share on other sites More sharing options...
Bloo Posted March 7, 2023 Share Posted March 7, 2023 Looks like 65-70 lb-ft. A 1940 Oldsmobile manual is here: http://www.oldcarmanualproject.com/manuals/Olds/1940/index.html Link to comment Share on other sites More sharing options...
philipj Posted March 8, 2023 Author Share Posted March 8, 2023 Thank you! that is certainly a great place to start... I might go about 10lbs under to be on the safe side to start with, and get to the 65 on the final retorque... Link to comment Share on other sites More sharing options...
Bloo Posted March 8, 2023 Share Posted March 8, 2023 It is desirable to go in at least 3 stages to avoid stressing the cast iron too much when the gasket compresses. Nothing wrong with more. Link to comment Share on other sites More sharing options...
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