Randy D Posted August 22, 2021 Share Posted August 22, 2021 Looking for a few opinions. My 1920 big Six Studebaker runs good but has a knock that I'm not certain is normal. I know old engines are noisy, just wondering if I should plan a rebuild this winter. 25k miles, 1 family, mostly all original. Runs good otherwise. Doesn't use oil. Had the pan off last winter and everything looks great. New clutch Lining and radiator core also. Now the water pump leaks badly and I'll need to tear into it again anyway. Can I even get parts if needed? Any idea where I can get a repair manual? Link to comment Share on other sites More sharing options...
edinmass Posted August 22, 2021 Share Posted August 22, 2021 While running the engine at a fast idle, short out one plug at a time and see if the noise goes away as you check each hole........80 percent of the time, it will tell you where your problems are at. Also, more or less noise when it’s warm versus cold? Link to comment Share on other sites More sharing options...
Stude Light Posted August 22, 2021 Share Posted August 22, 2021 Just to expand on what Ed suggested....If there is too much clearance in one particular connecting rod bearing, you may get a knock vs a tick. What you are doing as you ground each spark plug is eliminating the downforce on the connecting rod and rod bearing at the crank during the power stroke. If you do a have bad rod bearing, you will generally hear a change in the level of knock. It may not totally go away but it should be a noticeable change. I would just use screwdriver to ground each plug to the head (make sure it has a well insulated handle). Another reason an engine may knock is too much spark advance so you should try fully retarded vs advanced or just put a timing light on it and verify you have correct ignition timing. Also, do you notice the knock getting worse when you apply more power? Like when you open the throttle rapidly at idle (you don't need to hold the throttle open and keep it revving, just during the time you are accelerating the crankshaft). Good luck! Link to comment Share on other sites More sharing options...
old car fan Posted August 23, 2021 Share Posted August 23, 2021 If the water pump shaft is good,repack it. No need to take it apart. Link to comment Share on other sites More sharing options...
nvonada Posted August 24, 2021 Share Posted August 24, 2021 You might get lucky. On my car if the dipstick rotated to a certain angle it will hit a crank counterweight when the engine is hot. Sounds just like a rod knock. I about had a heart attack! Now there is a line painted on the dipstick to keep that from happening... Link to comment Share on other sites More sharing options...
Randy D Posted August 24, 2021 Author Share Posted August 24, 2021 Noise seems consistent while accelerating under load but I can't hear it at idle. Also, is this the water pump packing nut? Do I just tap it tighter with a punch? Sorry but can't find a service manual anywhere. There's no dipstick that I'm aware of. Just a float. Link to comment Share on other sites More sharing options...
George Rohrbach Posted August 24, 2021 Share Posted August 24, 2021 Here is some info on the water pump. Link to comment Share on other sites More sharing options...
Stude Light Posted August 25, 2021 Share Posted August 25, 2021 I would still do the spark plug grounding test. Just use a wire with alligator clips and ground one plug at a time, do a quick drive and accelerate and see if one of the plugs makes a difference. It's not going to run so great on 5 cylinders but it's just a noise test. If you find one where the knock goes away then you know what cylinder to go after to dig a bit deeper. 1 1 Link to comment Share on other sites More sharing options...
Bloo Posted August 25, 2021 Share Posted August 25, 2021 You could use a punch I guess, carefully, but a tiny pit of prying with a screwdriver ought to do it. We are not talking about very much force at all. Go slow and watch what happens. Don't overdo it. Make it slow down a lot, then maybe carefully get it down to a drop every few minutes. If you make it seal completely it will just burn the shaft up and you will need a new shaft. The nut just compresses the packing, it is not "tight" in the traditional sense. If it is so hard to turn that you would need a punch to move it, it is probably out of packing and bottoming out. In that case it needs more packing. That one looks like it would be tough to get more packing in. If you have to take it off of the car anyway, it would be prudent to have a good look at the shaft and bushings. Link to comment Share on other sites More sharing options...
dl456 Posted August 25, 2021 Share Posted August 25, 2021 Randy, You can replace the water pump packing on the car. It is much easier with a spanner but can be done with two screwdrivers. No punches allowed. Time consuming but doable with the right curse words. These engines have some of the best Babbitt material from stock You may have a rod knock but I would suspect piston/wrist pin issues before bearings. Just a quick question,did you set the dipper clearance to the troughs when you had the pan off ? We’re all the dippers present and good shape? These are usually die cast. Dennis Link to comment Share on other sites More sharing options...
Randy D Posted August 26, 2021 Author Share Posted August 26, 2021 I only know that the dippers were all there and everything was nice and clean. Didn't know they could or should be adjusted. I'll try grounding each plug and driving tomorrow, weather permitting. Turning the packing nut a little fixed the problem. Thank you. 2 Link to comment Share on other sites More sharing options...
Randy D Posted August 27, 2021 Author Share Posted August 27, 2021 Well look what I found buried in my fathers stuff. Surprised I haven't seen this before now. This should help immensely. 3 Link to comment Share on other sites More sharing options...
Randy D Posted August 27, 2021 Author Share Posted August 27, 2021 Number 6 is knocking. Any sources for at least gaskets? Rod bearings? I don't want to disassemble if parts are not available. Also noticed bubbling around a couple cylinder head nuts like a leak. Link to comment Share on other sites More sharing options...
edinmass Posted August 28, 2021 Share Posted August 28, 2021 One step at a time. If it’s knocking, you need to figure if you can do the job, if you can afford to do the job, and a worst case scenario of time and money. Nothing is cheap today. Sit back and think on it, ask around what others spent on doing an engine. A half ass fix would probably run a grand, and it may hold up for an minute, an hour, a day, or a lifetime. What’s your expectation for the car? If your not in love with it.......think long and hard before you jump in. Take a few days. Did the cylinder power balance test help you ID the hole? Link to comment Share on other sites More sharing options...
Stude17 Posted August 28, 2021 Share Posted August 28, 2021 On 8/26/2021 at 8:30 AM, dl456 said: Randy, You can replace the water pump packing on the car. It is much easier with a spanner but can be done with two screwdrivers. No punches allowed. Time consuming but doable with the right curse words. These engines have some of the best Babbitt material from stock You may have a rod knock but I would suspect piston/wrist pin issues before bearings. Just a quick question,did you set the dipper clearance to the troughs when you had the pan off ? We’re all the dippers present and good shape? These are usually die cast. Dennis I agree with DI456 that Studebaker had very good Babbit bearings and that your knock may be a loose piston wrist pin (Gudgeon pin). If it were my engine I would remove the head to see if there is any evidence of the pin damaging the bore. Loose pins can damage the bore to the extent that it will require sleeving to save the block. https://www.google.com/url?sa=i&url=https%3A%2F%2Fgrassrootsmotorsports.com%2Fforum%2Fgrm%2Fwrist-pin-walk%2F179274%2Fpage1%2F&psig=AOvVaw0mpMYORk9vDHiMccKIrWcu&ust=1630229058409000&source=images&cd=vfe&ved=0CAgQjRxqFwoTCNDU6eq00_ICFQAAAAAdAAAAABAQ Link to comment Share on other sites More sharing options...
edinmass Posted August 28, 2021 Share Posted August 28, 2021 Stude “didn’t have good Babbitt bearings”, they had a good engine design. Babbitt bearing quality is directly related to the craftsmanship of the person doing it. I have seen high instances delaminated bearings particularly on Cadillac/LaSalle, Pierce Arrow, and Stude. The failure was caused by adhesion issues.......not bearing design or lack of oil. Just dropping a cap on engines with original bearings can cause failure today...... Link to comment Share on other sites More sharing options...
dl456 Posted August 28, 2021 Share Posted August 28, 2021 Studebakers did have superior Babbitt compared to most makes of the times. I have been inside many early special and big six engines from 16 to 24. I don’t recall fracturing or delamination unless caused by a known oiling problem. I agree more investigations are the next step. Can the knock be heard on a video? Does it come and go under load? Does it change when 6 is shorted? Dennis Link to comment Share on other sites More sharing options...
dl456 Posted August 28, 2021 Share Posted August 28, 2021 Sandy Olsen has your gaskets and hard parts are available from several sources. Are you a member of ASC? Link to comment Share on other sites More sharing options...
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