Jump to content


  • Content Count

  • Joined

  • Last visited

  • Days Won


PT81Jan last won the day on April 27 2018

PT81Jan had the most liked content!


About PT81Jan

  • Rank
    Senior Member, have way too much spare time on my hands
  • Birthday 04/12/1971

Profile Information

  • Gender
  • Location
    Germany; Friedrichshafen
  • Interests
    Especially Bikes and Cars of the 30s and 40s with Flathead engines (others are also welcome!)
  • My Project Cars
    - 1939 Plymouth PT81 Pickup Truck<br />
    - (1942 HD-WLA)

Contact Methods

  • Biography
    born 1971, married, children, 1st occupation: patternmaker, 2nd occupation: engineering technician
  • Occupation
    Designer / Engine Development


  • Location
  • Interests
    Still love my PT81

Recent Profile Visitors

870 profile views
  1. PT81Jan

    Throttle linkage

    Not sure, if this shows what you are looking for ... ? Of a 1939 Plymouth truck, but should be the same like on 1939 Dodge trucks.
  2. PT81Jan

    Show your tools.

    Does anyone of you know a Sirometer ? I always wanted to know the rpm of the engine when traffic forces to rush a bit on the main roads. Sure, I did calculate the rpm inr elation to a specific speed, but I always felt uncomfortable at main road speed where the engine starts to sound like a circular saw. So I was looking for a 6V 6 cyl. rev counter which I finally found and installed some days ago. But after a first test I was very disappointed. With just a bit throttle it indicated about 3.000 rpm. Then I found a tiny screw on the backside of the instrument, which allows to adjust the indication over a fairly wide range. But how to adjust it when you don`t know the real rpm ??? Here comes the Sirometer ! This mechanical rpm measuring device has been my Dad`s pride and joy since he was a young man. He did RC model plane stuff and took the Sirometer to tune his model engines. I went to him but he mentioned that he unfortunately lost it some years ago (he still mourns after it). So I did a www. search and to my surprise the company who made it still exists ! I ordered two (one he will get to his 79th birthday this year 🙂 How does it work ? It simply analyses the revolutions through the vibration of the engine which are led to an adjustable wire. When it swings it has picked up the exact rpms and shows it on a scale. Super simple in application but certainly not simple to invite and develop such a thing ! If of interest -> http://www.treysit.com/english/
  3. PT81Jan

    Lets see pic of your trucks

    Location: Very South of Germany A quick prestory to the pictures ... Today I went to the Lake to go for a walk with the dog and taking some pictures of my 1939 PT ... But first a quick jump to the last weekend. Winter suddenly has stopped, rain had washed away the salt from the roads over night. I went to the lake early in the morning. Sun was just before rising up. I could see a yellow orange stripe along the horizon, super clear water, swans slowly waking up. What a panorama !!! From our side of the shore you can see the mountains of the Swiss Alps, if the sky is clear. That morning they where super clear, white shining snow on top. Simply perfect ! Unfortunately I neither had a camera nor my PT with me. So I decided to come back the next weekend ... Today morning , Feb. 23rd, 2019 something between 6.00 and 6.30 a.m. Knowing that there is just one access to the shore and it is strictly forbidden to enter it with a vehicle, I arrived a bit too early. Drove in with a slight bad conscience. Nobody was there. But today, no mountain view, just a grey haze. No swan just some scattered ducks. No orange horizon. Damned. Since I took the risk to get serious trouble, I yet decided to take some quick shots with the camera and quickly sneak away off of the shore. Jumped into the truck, wrooom, rear wheels scrabbled in the sand, ooops. A bit less throttle, but too late. Rear wheels went deeper and deeper .... then a man walked by, he was looking a bit wrathful / surprised. I probably like a caught little boy. But hey, that was a colleague from work !! I quick explained my situation, he just: ohooohhh. Now to make it short. He rushed to his home, came back with his car and a rope. (Still nobody else came to the shore - biiig trouble, if the sheriff or a conservationist would have appeared). Hooked in the rope and towed me out of my awkward situation. Yesss !!! I asked him what he wants to get, but he did refuse ... "hmm, maybe a ride in the PT !?" he said. So yes, I gladly will take him to a tour along the lake !!! So here some adventure pics I shot, although they are certainly not perfect: Was it worth it ? For me YESSS !
  4. PT81Jan

    Oil Pump Plate Leak - 48 Plymouth 218

    Yes, there is a groove in the oil pump housing for a sealing ring. Red arrow in the picture below. I also had a slight oil leak there. The original ring had a cut. I first put in a standard O-ring but to my own surprise this didn`t seal as expected. Gladly I found a spare oil pump cover sealing ring in my gasket collection which has got a rectangular profile. I additionally applied a thin amount sealant to the area to the flat surface where the 5 bolt holes are located.Blue arrow. Voir là , no leak anymore. There are a lot of posts regarding priming. Maybe you will do a keyword search. I personally like the idea to fill the pump with Vaseline which has been previously posted anywhere here ...
  5. PT81Jan

    Manifold Stud Replacement

    I swapped all the manifold studs on my engine, and yes I did install them myself. I can´exactly remember how many of them are breaking through into the water jacket. Maybe 2 or 3 (?) But this easily can be seen when the specific stud is out. I don`t know, if leakage at that bolts is a common problem. Never had a leak there since the rebuild 5 years ago and regularly use. Good preparation and the right stuff is the basic for success in my opinion. Ah, and I think it is more difficult to get an installed + leaking stud leak-free. But again, ask 5 people, get 5 answers ... Just my experience ...
  6. PT81Jan

    Manifold Stud Replacement

    Ok, not trying to decide, if it is better just to swap those which are obviously no longer good or replace them all. It is fairly difficult to evaluate the condition of the bolts, not being in front of them. My comment in #2 is just what I would feel good about myself. I hate to do things twice (and I did ...). Regarding the risk of leaking studs: If you thoroughly clean the threads and apply a good sealer (I used one for higher temperature) to them there shouldn`t appear a leakage problem. At least I had zero problems on that. Good luck ! Jan
  7. PT81Jan

    Manifold Stud Replacement

    I think you already know what the best would be ... You don`t know the history of the engine, not sure if the studs which goes into the water jacket (not all) are leaking or not, you already have a complete set of new studs. Since this seems to be a rebuild, not a repair, the engine is out anyway. Best chance to get to the bolts (and other parts). You also mentioned that the manifold was cracked presumable due to improper bolting, so it is possible one or more have been over-stressed. Do yourself a favor and replace them all. You would bite yourself in the butt, if a stud breaks while final assembly and eventually already installed in the vehicle ... How to get them safely out ? I would several times apply a good penetrating oil where the studs are bolted to the block. Then put on two nuts to the stud(s) and counter them to each other. Apply a good amount of heat to the area of the block where the studs are located (heat gun, torch, ..). Take a wrench and carefully try to loosen it. Sometimes it is necessary to apply heat and let it cool down several times. If one should break, it is not nice but not a dooms day. (Let`s talk about it when it should happen). Good thing would then be, you know that it was time to replace that stud ...
  8. PT81Jan

    Chrysler/Plymouth Flat head Rebuild

    Thanks for posting this. Was watching part 1 and 2 some weeks ago, but didn`t get part 3 displayed. So for completion, here is part 1 & part 2 (Maybe moderators will move this to the Technical archive section ? Interesting for both the car & truck guys here)
  9. PT81Jan

    Airflow influence: Opel Admiral

    Just a slight data correction / supplement: The Opel Amiral has been produced from 1937 - 39. In the short period of production it had a pretty respectable market share. Even in competition to high class section like Maybach (which formerly was produced in the company location where I am working for). End of production reason was indeed the beginning of WW 2 which was in Sept. 1939. The engine of the Admiral was needed for military trucks then ... Anyway, you are right, the influence of some less successful designs often can be seen on later models of other manufacturers which had more success then. Maybe something for the OT (off topic) section ?
  10. PT81Jan

    1940 Radiator aftermarket adapted?

    Hi Dave, as mentioned above I used UHU Plus -> http://www.uhu.com/en/products/epoxy-adhesives-2-component/detail/uhu-plus-endfest-3002-k-epoxidharzkleber-1.html?cHash=70cb5d93b5a76faed4b9eb03ed1cf9eb I don`t know, if this is available in the US but I am sure there are comparable products. Have a look on: 1. on which stuff it is resistant against (Epoxy is resistant against most stuff that we use in our vehicles) 2. the temperature range in use (mine is -40°F to at least 212°F -> I wouldn`t worry with that upper limit, / short term is 356°F ) Jan Hi 40desoto, yupp, I also would have hated it to do it twice. I cannot guarantee, if that works for you. Depending on the condition of your radiator ... for me it absolutely has been worth the attempt. Not really difficult to fix and not much money spent. Still good up to now. Ah and although PITA´s seems to be resistant against high temperatures and water steam, I wouldn`t use it as a radiator 😉 "... most pita are baked at high temperatures (450–475 °F (232–246 °C)), which turns the water in the dough into steam ...." (WIKIPEDIA) Jan
  11. PT81Jan

    1940 Radiator aftermarket adapted?

    Not an answer regarding your aftermarket replacement question, but if I understood you right, you would prefer to keep your original radiator !? Mine already started to mark the territory out of two places of the honeycombs. I had good success repairing the original radiator myself. How ? My first thought was to solder it, but after the research it was more likely to damage it even more that way. Every info source I found recommended a 2-component adhesive. After emptying and pulling the radiator, I had to dry the leaking areas. Therefor I used a hairdryer. That process showed at least 15 - 20 (!) more places which were leaky. Super little but potential candidates to get larger. The warm air dried the honeycombs but the capillarity soaked the rest moisture out trough the tiny fissures. I marked them with a paint pen and dried it until no moisture came out (patience ...). Then I carefully cleaned the places with paint thinner and applied the 2-c adhesive with a brush (I used UHU Plus). (Not too thick, it will run away. In doubt do it in two steps) A bit of warm blow dryer air helps to make the adhesive temporary a bit thinner, so it better soaks into the fissures in the honeycombs. Finally painted the rad with a spray can. The repair was about 1 ½ years ago, no leaks anymore since then. Costs about 20€ / 23$. Maybe worth an attempt ...
  12. PT81Jan

    Interesting photos I have run across.

    I really like it how the adverts once were lovingly designed
  13. PT81Jan

    Enjoyable Christmas decorations.

    Haha, that was a really good one ! I went to the workshop today to visit my 24 advent friends ...yikes, there are just 4 left !!! Probably the other ones also joined to the choir. At least I know now, that they were singing, not I ...
  14. PT81Jan

    48 pu electrical

    Not the specs of a `48, but if it helps, the "how to" should be pretty similar ...
  15. An often discussed issue caught me now too: poor quality breaker points. In this specific case not the points of the distributor but the voltage breaker point of the regulator. Basically the same ... My battery has no longer been properly charged, so I checked the charging system and found that worn pair of points. I tried to file them smooth, but these were so horribly burnt, that not much of the material was left. Besides the material was so soft that it would not have last long until the next failure. Since I did not want to swap the whole regulator, I tried to find replacement contacts. I did not really expect to find one, but … ... long story short, I think I found a source which I think is worth to share and may help others with chunk breaker issues, too: Got them at a supplier* which sells service parts for old pinball gaming machines ! NOT made in China like most at a fairly reasonable price (0.85€/each) ! Point material is tungsten and a file test makes me confident they will work a while. On top is that the diameter exactly is the same as of the original points. They have a small pin on the back side to stick it into the breaker arm and can be fixed with a slight punch to the pin. That`s it. * is in Germany but I am pretty certain that gaming machine services exists almost everywhere in the world

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use