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Zip tying the pump up and out of the way will work, but I've also saw them begin to leak at the hose attachments after doing this, so be a little careful and pay attention. The hose can be old and brittle and just tying the pump up, can create a sharp enough angle at the attachment point that it puts enough stress at the connection to create a leak path.
Long term solution: You can find cars being parted out. This is not a high demand item, is easy to remove and provides good protection. Find another, a previous owner was probably too impatient to deal with removing the guard to get to the pump.
Zip tying the pump up and out of the way will work, but I've also saw them begin to leak at the hose attachments after doing this, so be a little careful and pay attention. The hose can be old and brittle and just tying the pump up, can create a sharp enough angle at the attachment point that it puts enough stress at the connection to create a leak path.
Long term solution: You can find cars being parted out. This is not a high demand item, is easy to remove and provides good protection. Find another, a previous owner was probably too impatient to deal with removing the guard to get to the pump.
Agreed… should be easy to find. But would advise to not get distracted by it and return to the original hard start / poor idle/ fuel leak issue. (Says me who spent Sat polishing his car when what it really needs is a new exhaust).
It will start about 50% of the time if I don't use the choke and instead slam the gas pedal. It still won't idle right, but even just slightly touching my foot without any force to the gas pedal keeps it running. Could that be an idle speed or mixture adjustment thing? And if so how do I go about getting a tachometer working to adjust it? Could my missing tach and inverted ignition be because of my igniter and coils? Or could that be timing? I'm trying to find somewhere in Arizona that has an rx7 for parts i can pull from. For instance, the axle shaft that was damaged when my wheel fell off. Or my speedometer cable, which is missing that center probe and is just an empty cable at the transmission side of things. Thanks for all your help so far everyone!
It will start about 50% of the time if I don't use the choke and instead slam the gas pedal. It still won't idle right, but even just slightly touching my foot without any force to the gas pedal keeps it running. Could that be an idle speed or mixture adjustment thing? And if so how do I go about getting a tachometer working to adjust it? Could my missing tach and inverted ignition be because of my igniter and coils? Or could that be timing? I'm trying to find somewhere in Arizona that has an rx7 for parts i can pull from. For instance, the axle shaft that was damaged when my wheel fell off. Or my speedometer cable, which is missing that center probe and is just an empty cable at the transmission side of things. Thanks for all your help so far everyone!
Good thread on tach here. https://www.rx7club.com/1st-generati...985-gs-826572/
If you are able to get a tach running, let me know and I'll talk you through the mixture and idle speed adjustment. Its not hard, but there are a couple of variations on where exactly the screws are, and some confusing advice on how to do it.
A bad wire, coil or igniter could indeed be related to the hard start and not running except with light touch on gas pedal. One of my spark plug wires came loose yesterday on the way to Cars and Coffee, and left me down one spark plug. Exact same symptoms... tried to stall at idle, but would keep running with a light foot continuously on the gas.
Personally I would wire up the car starting at the coils through the dizzy and to plugs the way the factory manual says it should be. Then see if you can check you are getting spark at all four plugs.
Just to check other possible causes, are you still seeing fuel on outside of carb body or on top of carb under air cleaner?
For parts watch the for sale section of this forum daily. There are often people parting out cars. I have also had very good luck sending a shopping list to riggsvintagemazda.com. They have a bunch of pick and pull style RX7 wrecks that they are willing to search for what you want and quote prices for. I was able to source some hard to find parts from them after not finding them elsewhere. And extend your search to Australia if shipping costs allow, there is a huge RX7 following there, and just received some unobtainium rear light rubber trim from there!
Yes, I am still seeing fuel around there. Just did my diff fluid, tranny is next whenever I move it to a spot where I can jack it up to access it. Not sure what oil I should go with so im holding off some on that, it looks semi ok. Tomorrow I will for sure be looking into the ignitors, spark, and compression. I do believe the seafoam actually helped some, maybe not by much but progress is progress. I will be amazed if I can get my tach working, great step in the right direction!
Update: the tach works and it idles! Ignition is no longer flipped! I cleaned my igniters with wd40 and everything just started working, so im going to do spark plugs soon. It idles high tho, at about 2200 rpm. Any guides on timing it? And adjusting idle so that its not so high, unless the tach is off by some. Thanks for all the help!
Update: the tach works and it idles! Ignition is no longer flipped! I cleaned my igniters with wd40 and everything just started working, so im going to do spark plugs soon. It idles high tho, at about 2200 rpm. Any guides on timing it? And adjusting idle so that its not so high, unless the tach is off by some. Thanks for all the help!
Excellent!
To see if tach is close…. Here is the sound of my FB at 2200 (your speed) and at idle 800. Compare to sound of your engine and see if it sounds close enough.
Best approach is to work on the idle, then timing only if needed. Here are instructions on adjusting idle and fuel mix. You do them at the same time. The throttle adjust is waaaaay under there…. Look for two screws close together, it’s the larger one on the left. Helps to have a really long cross head screwdriver and a flashlight. Some people even dab them with nail polish to make ‘em easier to find next time.
Let me know if your carb does not seem to have the screws in the locations shown.
It definitely sounds more like 2200 rpm, maybe even higher. Mine is missing the back half of the exhaust so its very easy to tell if its revved higher or lower than normal. I just have to hope that it will idle that low, since it still wont start on its own and the carburetor is still of questionable integrity. Driving it around, it seems to stutter and do little backfires alot, so im not sure if thats a sign of anything bad or just adjustments needing to be made. I will put new spark plugs in it and do a compression test soon!
Good compression test video here. Using a cheap piston engine compressor will give you enough info to tell if you need to rebuild engine or move on to timing and carb
Just got some time to look at my rx7 again, I tried to adjust the idle via the idle speed screw, and it did absolutley nothing. Still stuck at 2200 rpm. Idles closer to 3100 when cold, anything that could be overpowering the idle speed screw when it comes to idle? Still waiting on avalibility of a friend to do a compression test.
Just got some time to look at my rx7 again, I tried to adjust the idle via the idle speed screw, and it did absolutley nothing. Still stuck at 2200 rpm. Idles closer to 3100 when cold, anything that could be overpowering the idle speed screw when it comes to idle? Still waiting on avalibility of a friend to do a compression test.
How’s the throttle cable adjustment? Follow the throttle cable housing to where it enters the carb and you will see see a threaded adjuster with a nut. The throttle cable housing stops here, and the throttle cable itself continues to where it attaches to the linkage. That section of the exposed cable should be slightly slack, not pulling on the linkage at all. I will send pics from service manual later today.
Do get the compression test done. You can set the gauge up so you can film it from the drivers seat so a one person job. If the symptoms you described initially are bad compression then deal with the resulting need for a rebuild first as all other work would be wasted time. See the recent thread on this forum entitled ‘No start on 85 12a’
Nothing specific for adjusting the throttle cable at the carb end in my factory manual. But I am looking at my 81FB this morning and all cables going to the carb… throttle, choke, hot start… are set the same way. The bare cable as it emerges from its housing and adjuster near the carb has a little slack. With the engine running and warmed up if I push my finger against each cable and move it maybe 1/4 inch the rpm’s go up. Check each cable and make sure they have a little slack rather than being tight and pulling the carb open.
I looked at one of the cables going to my carburetor, and I can just move the whole thing off with my fingers. I was tired when I went to go work on it (3am realization) and also tried fixing my headlights. Now they pop up, but refuse to go down. I think I put the switch back together wrong, does anyone have a piture of the internals of the switch and the switch rocker orientation? I finaly have somw time to work on it again so compression test and spakrk plugs are soon to come!
Cables should be attached with their clips and adjusting nuts. See pic below. You may have fewer cables if you don’t have cruise or start assist. Important thing is at idle none of the
cables should be pulling on its linkage, each should be adjusted to have a little slack. Imagine if the throttle cable were slightly tight; it would be like running your engine with your foot in the gas.
Also below is clear pic of where the idle speed adjustment screw is, just to make sure you are turning the right screw. It’s a cross head. Left to slow idle, right to speed it up. When I get home in a couple of days I will look and see if I can observe what the idle screw pushes against
and if its possible to see if it’s actually mechanically doing anything or if a tight cable or a bent / hung up linkage is over-riding the adjustment screw.
Your high idle may also be a vacuum leak. But rule out cable tension and idle speed screw first as they are easier to diagnose.
Don’t worry about the lights. Concentrate on idle, hard start and choppy running. Plus car looks cooler with lights up.
I believe it is indeed the throttle cable, just did compression and plugs. I heard something about a 65 psi death knell, mine gets 65 psi. Not 100% sure if I did it right, I had my buddy crank it so I could get a better camera angle, and he didn't crank it for very long. It was in intervals of 35 to 65 psi bursts, all equal distance apart. Does this mean anything bad? Or should I test it again and do it longer.
Take a video of the compression tester gauge, and crank for 10 seconds or so, hold for a
few seconds then crank again for 10 seconds. Do this for front and rear rotors, so send us two videos. Do the test after running the engine long enough for the temp gauge needle to climb above the ‘C’.
Do the test again and send the videos by posting them to YouTube and posting a link here. What you saw is bad news, and would be good to double check with a second test to confirm the numbers are repeatae. 65 is very low, indicating worn apex seals or wear to inside surface of housing. The pulsing between 35 and 65 tells us one seal is particularly bad.
I cant test it tonight, but i have footage of the previous tests I did. Turns out I left that anti backflow valve in the tester, thats what I did wrong. I now also have a video of after fixing the throttle cable, it will die if not idling at 2000rpm. Not exactly sure how I would even begin a rebuild, I dont have enough garage space or any engine removal tools... Ive also learned the reason the car tried to start, is because if i have the hazards fuse in, it will attempt to crank when it has power.
You mentioned that you think you left the none return on the compression tester. Do go ahead and remove that none return and test again, posting a video of the compression gauge during testing. The none return valve will mask a bad seal as it will record the highest pulse and bridge right over a low pulse.
Its been a while, my jeep just had some suspension things I had to take care of. But now I've fixed all the gauges, and I'm still taking care of the rear axle. I haven't gotten around to a compression test again, but hopefully I will soon. Did all the fluids but coolant and it still dies, the furthest back cable is what I've been adjusting for it to idle.
Its been a while, my jeep just had some suspension things I had to take care of. But now I've fixed all the gauges, and I'm still taking care of the rear axle. I haven't gotten around to a compression test again, but hopefully I will soon. Did all the fluids but coolant and it still dies, the furthest back cable is what I've been adjusting for it to idle.
I finaly got around to doing a correct compression test. The front rotor was about 80, and rear was 90. I have videos and pictures and will add them soon. Maybe I can just get away with a carburetor rebuild while I wait to move to somewhere with garage space to start a rebuild? Or anything else keeping it from idling under 2800 RPM. The fuel lines seem pretty rusted, not sure if that or fuel delivery would effect that. Also anything vacuum wise I should look into? I know my carburetor is pretty iffy on its cable positions and adjustment so whats the factory spec on the idle and air fuel screws?
Once started, turn the throttle adjustment screw clockwise. Does the screw turn and does the idle speed go up? Then turn it counterclockwise, does the idle speed go down?
What happens to the mixture screw if you do the same things?
Is there slack in the exposed wire of each of the throttle, choke and assist cables as they enter the carb. To rule out cable issues, what happens if you start the car and then remove all the cables?
I have not messed with the mixture screw, but my idle is currently being held by one of the cables holding tension. Its the cable furthest to the rear, tightened most of the way so it won't die since it won't idle lower than 2k. Would mixture help that or am I looking in the wrong places? And what do you mean by cables, battery cables? Or throttle, choke, etc
10-02-23 | 11:53 AM
