nacmlamerikx Posted June 5, 2023 Share Posted June 5, 2023 (edited) I'm hoping someone can help me with making our 612 run properly, I'm out of ideas.. I have around 4 bar (60lbs) compression (cold) on al 6 cylinders, great spark on all cylinders but it sounds like its only running on 3. Does not start withouth start pilot and after a small ride the first 3 cylinders are significantly colder than the last 3. I cleaned the carburator and made sure that all jets are good. Replaced all the ignition parts (spark plugs, wires, condensor, coil, breaker points). Set the spark plug gap to 0.6mm (0.023"). Distributor shaft does not have excessive play. The car has 0 power and I have to advance the ignition fully to get it somehow moving, which causes the engine to run hot on a warm day. The breaker point gap is set on 0.5 mm (0.02"). Yesterday I pulled the valve covers and inspected them, everything looks good and loose, still have to check the valve lash but on first sight it doesn't look abnormal. I'm out of idea's, was thinking about pulling the head off to check the head gasket/pistons but it's not easy to get a new head gasket for this model in Europe. Does anyone have some tips I can check before pulling the engine apart? Engine running and drivingValves from the first 3 cylinders Edited June 5, 2023 by nacmlamerikx (see edit history) Link to comment Share on other sites More sharing options...
JFranklin Posted June 5, 2023 Share Posted June 5, 2023 Make sure the ignition is working properly before tearing into the mechanicals. Faulty ignition can act like what you describe. Link to comment Share on other sites More sharing options...
Bloo Posted June 5, 2023 Share Posted June 5, 2023 Inspect your distributor cap under a bright light. Also crank with the distributor cap removed, so you can see which way the rotor turns. Once you have verified which way it turns, double check the firing order. Look at how the rotor connects to the distributor cap at the center. Some distributor caps have a spring loaded carbon brush. Others have a carbon contact that does not move, but those types use a flat spring contact on the rotor that reaches up to touch. Either way the two must touch. Make sure nothing is missing or bad there. Is there anything odd about the ignition system? Dual points or dual coils or any other complications? Link to comment Share on other sites More sharing options...
Graham Man Posted June 10, 2023 Share Posted June 10, 2023 Careful on the firing order, these are set up just like a Dodge, you have to index the distributer drive when installing the cam shaft so most likely it is about 15 degees off (from factory pictures), just check number 1 TDC. Link to comment Share on other sites More sharing options...
nacmlamerikx Posted July 10, 2023 Author Share Posted July 10, 2023 Hello guys, we checked all of the ignition parts again, I went to a guy who has some oldschool sun engine testers, we put the distributor on a testing bench and everything is good. Coil, condensor and firing order was also good. The car still runs poor. I checked the spark plugs again today and they were all 6 black. I was wondering it could be a jetting issue so removed the main jet and to my suprise there was a solex X130 jet in it. There was also a normal plug to close the main jet hole, in all exploded views I see main jet adjustment (zenith C71-21). I want to buy this main jet adjuster and a correct main jet, does anyone know the correct size for a graham 612? Link to comment Share on other sites More sharing options...
Peter R. Posted July 10, 2023 Share Posted July 10, 2023 What distributor and carburetor are you using on your car….? 🤔 Link to comment Share on other sites More sharing options...
Graham Man Posted July 10, 2023 Share Posted July 10, 2023 1 Link to comment Share on other sites More sharing options...
Graham Man Posted July 10, 2023 Share Posted July 10, 2023 1 Link to comment Share on other sites More sharing options...
nacmlamerikx Posted July 11, 2023 Author Share Posted July 11, 2023 (edited) 10 hours ago, Peter R. said: What distributor and carburetor are you using on your car….? 🤔 It has a remy delco 639v distributor and zenith 11644 (Z1-162) carburetor. 8 hours ago, Graham Man said: Thanks again for this info graham man, but the ignition parts are 100% good. We checked the distributor and all components on a test bench. And we resetted the timing as described in the manual you shared. This is how my spark plugs look. And this is what I found in the zenith manual. I know the number of article 56 but I need part 54 for my carb. The Solex X130 jet that was in it looks way different than in this exploded view. Edited July 11, 2023 by nacmlamerikx Added more pictures (see edit history) Link to comment Share on other sites More sharing options...
Peter R. Posted July 11, 2023 Share Posted July 11, 2023 I think I can help you with an adjustable main metering jet. Does your engine have sufficiently compression on all cylinders? Make sure there are no air leaks in the intake set-up (carburetor flange, excessively worn throttle shaft, manifold gaskets, cracks in the casting, heat riser etc.). Link to comment Share on other sites More sharing options...
Peter R. Posted July 11, 2023 Share Posted July 11, 2023 I don‘t think your car was originally equipped with a Zenith carburetor so the carburetor you are currently using may just be a bad choice. What‘s the size of the venturi tube? Be careful what you are using, a wrong carburetor can ruin your engine. Link to comment Share on other sites More sharing options...
Graham Man Posted July 11, 2023 Share Posted July 11, 2023 The 2nd wet plug looks fouled, not firing. Link to comment Share on other sites More sharing options...
nacmlamerikx Posted July 12, 2023 Author Share Posted July 12, 2023 21 hours ago, Peter R. said: I don‘t think your car was originally equipped with a Zenith carburetor so the carburetor you are currently using may just be a bad choice. What‘s the size of the venturi tube? Be careful what you are using, a wrong carburetor can ruin your engine. Hello Peter, the compression on al 6 cyl is about 4 bar. I have no leaks or cracks on the inlet. From what I can find is that carb is orginal for a graham paige 612. I found some info about the standard size main jet the carb comes with and it should be a Zenith C52-6-25. The adjusting is C71-21. Is that something you can get you're hands on? I see you are located in Switzerland so that would be awesome. 15 hours ago, Graham Man said: The 2nd wet plug looks fouled, not firing. Yes, the strange thing is that the last time when I checked the spark plugs cyl 3 was fouled. At first I thought I had bad piston rings on that cylinder but now it is cyl 2 so it could be a jetting issue. Link to comment Share on other sites More sharing options...
Peter R. Posted July 12, 2023 Share Posted July 12, 2023 I think this is the jet you need. I‘ll send you a PM so you can provide me with your shipping address. Link to comment Share on other sites More sharing options...
Peter R. Posted July 12, 2023 Share Posted July 12, 2023 9 hours ago, nacmlamerikx said: From what I can find is that carb is orginal for a graham paige 612. The Graham-Paige 612 was factory equipped with a Johnson carburetor (auxiliary air type carburetor). There are two major issues with these carburetors: 1. The Johnson was not a good carburetor (Correct, Ed?) 2. The Johnsons used on Graham-Paige were made out of pot metal. They crack and fall apart over time. There‘s probably not one good Graham-Paige Johnson carburetor out there on this planet. This explains why someone replaced it with a Zenith Z1-162 (11644) carburetor. By the way, Z1-162 is a rather primitive carburetor that was used on industrial applications such as stationary engines or tractors. No acceleration pump because of constant rpm operations etc. 11644 was a replacement carburetor for Buda, Continental and Gardner-Denver engines and other applications, such as Oliver, Schramm and John Deere etc. I assume it is too small for your 612 and therefore is running too rich. But hey, since you‘re using a tractor carburetor, it is okay when your car is running like a tractor….🙂 However, I would replace your Zenith with a Carter BB1A or BB1D Universal Carburetor (or a Stromberg SF). 1 Link to comment Share on other sites More sharing options...
Peter R. Posted July 12, 2023 Share Posted July 12, 2023 Some info on the Carter replacement carburetor. 1 Link to comment Share on other sites More sharing options...
Graham Man Posted July 13, 2023 Share Posted July 13, 2023 Johnson was junk when it was made, Graham-Paige only used them one year, then went to Detroit Lubricators (also expensive), Have never used Zenith, Strombergs are good. I run a Carter BB1 (1 1/4") on my 610 and 45, starts and runs great. They are getting more expensive. I look for them at swap meets. https://www.ebay.com/itm/185977926492?epid=5010773560&hash=item2b4d25f35c:g:v4gAAOSwX0phroNn&amdata=enc%3AAQAIAAAA4D7LpUhHcdgqfjIN9L4Gzg9xCzqxFgM8U%2FvG80V3zIY57p7haIcnUiEYmx37bbOuYsRfota%2BrANxYoTFU7OK%2Fh9Cr2iFXjN4JyTgKxqArzDQvxNluSY%2Bp5kyPDZ8Wo9qda%2Bd7T9WG87n3N0R29aEwunbmakD7X6KPAxlwgWavNDBTrG61h8qteb316%2F5gS95gQ4v8Zv3w4pnSaAQcgg4w%2FbKWHOcY01ox6EM4u9YBSw8gTlrRV2Nk6PeHjIWuVvnfd%2BpzpROJqp9Z798Ej3NWQKefi3qSV6rBAi9%2Fv3plpJw|tkp%3ABFBM3MmH1qli Link to comment Share on other sites More sharing options...
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