blown240 Posted July 10, 2015 Report Share Posted July 10, 2015 Yesterday I was helping Tolkmod work on his car. We installed a Petronix electric ignition, and set timing. His timing was a 1 degree AFTER tdc. I set it to 10 degrees BTDC at idle. Right now his idle is about 1300, and i can't get it any lower. It looks like the idle screw isn't even toughing the throttle shaft at all. That makes me think that there may be something off inside the carb. Vacuum is good and there appears to be no leaks. Could the butterflies be installed upside down? The PO says the carb was recently rebuilt, and its pretty clean. Here a re some pics: 1 Quote Link to comment
banzai510(hainz) Posted July 10, 2015 Report Share Posted July 10, 2015 choke still on?????????? 2 Quote Link to comment
blown240 Posted July 10, 2015 Author Report Share Posted July 10, 2015 I don't think so, the car was nice and warm. But maybe the choke isn't opening up enough. Is there an adjustment for that? Quote Link to comment
Dirttrack510 Posted July 10, 2015 Report Share Posted July 10, 2015 Vaccum leak? Maybe gasket under carb or vacuum cap/hose off or broken? Quote Link to comment
datzenmike Posted July 10, 2015 Report Share Posted July 10, 2015 Choke on or not shutting off Fast idle cam on or stuck on or part on. Throttle cable too tight Foreign object stuck in primary throttle plate 1 Quote Link to comment
blown240 Posted July 10, 2015 Author Report Share Posted July 10, 2015 Vaccum leak? Maybe gasket under carb or vacuum cap/hose off or broken? All vacuum hoses are new, and carb gasket good. Vacuum seems good. Choke on or not shutting off Fast idle cam on or stuck on or part on. Throttle cable too tight Foreign object stuck in primary throttle plate These are all possibilities, except the throttle cable. It has a tiny bit of slack. Quote Link to comment
banzai510(hainz) Posted July 10, 2015 Report Share Posted July 10, 2015 make sure the carb vacuum advance hose is comming from the carb to the distributor and not from the intake manifold, THis has happened before. otherwise go back to above staements stick finger on plate to make sure its fully or more closed ans see if idle goes down can you seee if carb float bowl is over full ??Highly dought this but Im only reaching here now. 1 Quote Link to comment
Doctor510 Posted July 10, 2015 Report Share Posted July 10, 2015 Pull off the top of the air cleaner and LOOK to see IF the coke plate is vertical. NEVER assume anything, it's like being a "little bit" pregnant. Quote Link to comment
Stoffregen Motorsports Posted July 11, 2015 Report Share Posted July 11, 2015 If it was recently rebuilt, did it get assembled properly? Sometimes the linkage pieces and their associated spacers/bushings get bound up. Try loosening the nut on the throttle shaft (maybe both of them) and see if anything changes. Try disconnecting the linkage rod that goes to the vacuum diphragm and se if that helps. Go from there. Quote Link to comment
datzenmike Posted July 11, 2015 Report Share Posted July 11, 2015 Never assume we know every person or vehicle. I had to look this up but we're talking about someone else's car, a '74 B210. Helpful info as some carbs have specific problems their owners know about and can comment on. First there's a report that this carb was recently rebuilt by a previous owner. (this is deathly bad info, as POs are known to be idiots. Might also be the reason this was passed into Tolkmod's hands?) (j/k) So we know it was definitely messed with and nothing is off the board... anything could be missed placed, upside down, wrongly adjusted. The idle screw is not bottomed on the stop but this is not necessarily indicating that the throttle plate is open. Maybe, maybe not. The secondary could also be stuck slightly open and gas and air for a fast idle could be getting to the engine through it. I've had this happen on a Z24 engine, drove me nuts finding it. A push with a pencil on the secondary plate closed it and fixed the problem. It was just stuck. The dash pot may also be stuck or poorly adjusted and holding the throttle away from it's stop.. One other source is the servo or throttle opener in the first picture. It has a vacuum source and may be on when it shouldn't. I can't find evidence of a BCDD on this carb and maybe the throttle opener is a substitute for this. I had a '76 and there is a switch inside the speedometer that holds the throttle slightly open above 10 MPH. When slowing to a stop I noticed the car would slow at a steady rate and suddenly drop at 10. The part open throttle reduced unburnt gas emissions on deceleration. I think the throttle opener is the round thing in this picture... . 1 Quote Link to comment
Stoffregen Motorsports Posted July 11, 2015 Report Share Posted July 11, 2015 If the vacuum line is disconnected (and the source plugged) and the idle drops, this is your problem. There's an old saying, "never let your neighbor touch your carburetor." 1 Quote Link to comment
datzenmike Posted July 11, 2015 Report Share Posted July 11, 2015 If the vacuum line is disconnected (and the source plugged) and the idle drops, this is your problem. There's an old saying, "never let your neighbor pack your parachute." 1 Quote Link to comment
Tolkmod Posted July 11, 2015 Report Share Posted July 11, 2015 do you guys have a link to a product sheet or break down of this carb? I don't even know what type it's called, or what part # to look up. I want to do some research on it, see if I can start figuring out what you all are talking about lol I rely to heavily on Blown240's skills, I want to try to bone up on it as best I can so that I can at least try some of the suggestions you guys are giving. Thanks! Quote Link to comment
Stoffregen Motorsports Posted July 12, 2015 Report Share Posted July 12, 2015 Crickets... Quote Link to comment
Tolkmod Posted July 13, 2015 Report Share Posted July 13, 2015 Crickets... Hate those things.... seriously, hate'm :sneaky: Anyway.... so I've done some serious research and looked up a ton of stuff, and after comparing it to what some of you have posted I started in on some simple diagnostics. I noticed first off that my choke butterfly (after fully warming up the engine) was no where near fully open at idle, so i played with it for a bit, holding it fully open and watching as the idle dropped and ran smoothly, so with a small amount of confidence I figured out how to adjust the choke and moved it one notch leaner (now at top center with the notches). As soon as I did that, I now get a really beautiful 800-900 idle. After about an hour test drive it was still staying consistently @ 800-900 RPMs on idle but i want to drive it for a few days before I pat myself on the back. What I have noticed though is that with the lower idle I get a lot of drops in voltage from my alternator, sometimes it'll even flash the "charge" light. And I can't even run my headlights when at idle, it chokes and tries to die off before i gas it a little. I'm guessing that the PO (I'm gonna say the PO's mechanic, as I'm confident he wasn't able to work on the car himself) compensated with the idle to not only help with the charging issue, but also the vacuum leaks we found previously. With all those fixed (and hopefully the right fuel mixture/choke settings dialed in) I can now start diagnosing other issues. I've read a few of the alternator threads here on ratsun, but most of them point to 510's and 620's and such. Anyone have any experience with higher amp b210 alternator alternatives? I'm putting in more power munching items, as well as my sound system here soon. If my alternator is already having issues (and yeah I have a voltmeter on order to confirm that) I'd rather just get a higher amp one now, than have to worry about it later. Any ideas, suggestions, links or points in the right direction? Oh, and a serious thanks to all those that responded so quickly! It really helped! Quote Link to comment
Stoffregen Motorsports Posted July 13, 2015 Report Share Posted July 13, 2015 I don't buy new alternators anymore. I have a local guy that rebuilds all my starters and alternators. Usually when I'm having one built I will ask if there are any upgrades available and I almost always have him up the amperage. A totally custom built unit from him is usually about $100. That's starting with a core. Glad you figured it out. Quote Link to comment
Tolkmod Posted July 13, 2015 Report Share Posted July 13, 2015 Well, lol, I THINK I figured it out, we'll see in a few days. Then I'll be a little more confident about the fix. Do you know of anyone on soCal that rebuilds alts? Quote Link to comment
banzai510(hainz) Posted July 13, 2015 Report Share Posted July 13, 2015 since this is a B210 I assuem the smallest alt out there. Try another one as this one is going out soon. I have stack of Nissan alternaors from the dealer. Those are good. But lately they are now expensive. I dont know how the alternator is mounted in a 210 maybe a 510amper will fit but most have bigger hole size the the ears so mike shake around and thats not good Quote Link to comment
datzenmike Posted July 13, 2015 Report Share Posted July 13, 2015 The PO adjusting the choke richer to raise the idle is.... well to be kind... is just plain stupid. That's what the idle speed screw is for. To make sure you have maximum power available at idle .... clean the battery terminals and the cables. Check the belt is tight and not worn out. Worn brushes replacements used to be about $5. Any car alternator before '78 were external regulated and will fit your B-210. They were all about 50/60 amp. Quote Link to comment
Stoffregen Motorsports Posted July 13, 2015 Report Share Posted July 13, 2015 Here's a shop in Riverside, but they look more like the ones I try to avoid. http://www.alternatorstartersuperstore.com/ May be worth a call though. Quote Link to comment
Tolkmod Posted July 17, 2015 Report Share Posted July 17, 2015 Okay, so my little fix didn't work. After all the crud I've been through trying my hardest to research and read up on everything I can, blown240 and I have concluded that I have a choke issue with this thing. And with that statement, it makes me wanna go all homer simpson on this carb right now and choke it to death. :mad: I'm seriously considering just buying that webber upgrade carb and tossing this out in the street and running over it a few times for good measure. Quote Link to comment
datzenmike Posted July 17, 2015 Report Share Posted July 17, 2015 The choke is simple. When on a linkage pulls the fast idle cam on as well. Choke off the fast idle is off. Find which is causing the fast idle and adjust. It may just need WD-40 sprayed on it and work the linkages back and forth. Get a shop manual, cheaper than a weber. Don't run from an Hitachi to a weber to get away from the choke and fast idle.... Webers have chokes too you know. Quote Link to comment
Tolkmod Posted July 17, 2015 Report Share Posted July 17, 2015 But why does it run like crud when the idle is seemingly perfect? It sputters and feels like im loosing a ton of HP and just dumping fuel into it. But when i have a high 1.3k idle it runs great, no sputter, no HP loss... And it switches between those to states at will, i can go a day and have it high idle and running good, next day, nice low idle, runs like crud. Sometimes it even switches off when i stop the car, go do something for an hour and come back to start it. Lol I seriously need to find a big fat "datsuns for dummies" book. Quote Link to comment
Tolkmod Posted July 17, 2015 Report Share Posted July 17, 2015 So after calming down a little and venting my hatred for carbs, i found a good dealer service manual on ebay and bought it... Hopefully some light study will keep me from beating down this carb and alow some zen to retun to my Datsun motoring experience... Quote Link to comment
Stoffregen Motorsports Posted July 17, 2015 Report Share Posted July 17, 2015 But why does it run like crud when the idle is seemingly perfect? It sputters and feels like im loosing a ton of HP and just dumping fuel into it. But when i have a high 1.3k idle it runs great, no sputter, no HP loss... And it switches between those to states at will, i can go a day and have it high idle and running good, next day, nice low idle, runs like crud. Sometimes it even switches off when i stop the car, go do something for an hour and come back to start it. Lol I seriously need to find a big fat "datsuns for dummies" book. That is a good question. Maybe it's not carb related at all. Maybe the weights in the distributor are sticking...? And the high idle helps keep them "afloat". Quote Link to comment
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