Motschrocker Posted May 7, 2017 Report Share Posted May 7, 2017 Ive got a 1966 datsun roadster with a 73 L18 swap in it. Last year i had it driving pretty nice. Good power and acceleration. Its got a knockoff chinese hitachi on it btw. Towards the end of last fall it started to lack power and to get it home i had to choke it out. I am trying to get it right this spring. I adjusted valve lashes. Check and adjusted points. Double checked timing and made proper adjustments. It will idle really nice no misses that i can hear but under load it falls on its face and wants to die. Once i let off the gas it idles fine. I thought stuck float which a little tapping on the carb did change the idle, but same results driving. Fuel filter is clear. Tried a different coil which seemed to improve its ability to rev without stalling out but when i drive it stalls out. Do you think all these issues stem from the cheap carb? Quote Link to comment
racerx Posted May 7, 2017 Report Share Posted May 7, 2017 Do a compression check, check if engine is good. 1 Quote Link to comment
Roadster-ka Posted May 7, 2017 Report Share Posted May 7, 2017 Sounds like primary jet is clogged. You can try to clear it by revving the engine to 3k and covering the top of the carb for 2 seconds to try and pull the debris out of the jet. If this doesn't work, the jet would need removal to clean it. 1 Quote Link to comment
banzai510(hainz) Posted May 7, 2017 Report Share Posted May 7, 2017 primary jet clogged as mentioned. if runs better with choke pulled mean your running on the 2ndry side of carb to make it home changed the coil? and hope its a matching POINT only coil otherwise it will start popping iof you but a EI coil n there as it will use to much current and arch out the points 1 Quote Link to comment
datzenmike Posted May 7, 2017 Report Share Posted May 7, 2017 Primary jet part clogged and running lean. You can confirm by taking for a long drive and then pulling the plugs. The whiter they are the leaner it's running. They should be light brown or tan. Quote Link to comment
Motschrocker Posted May 8, 2017 Author Report Share Posted May 8, 2017 Sounds like everyone is in agreement. This will be my first carb cleaning. I found another thread in which datzenmike described how to clean the jets. I will follow that and keep you posted. 1 Quote Link to comment
Motschrocker Posted May 9, 2017 Author Report Share Posted May 9, 2017 I did a jet clean with the carb on the car using carb cleaner and it definitely helped, but the acceleration is still inconsistent. Hesitating and such. When i floor it and get the second barrel going it will accelerate nicley. Looks like i will need to pull the carb and do a thorough cleaning. Quote Link to comment
banzai510(hainz) Posted May 10, 2017 Report Share Posted May 10, 2017 do a Hawaiian tune up Rev motor to 6k then put a rag over the carb so it sucks the jets clean and hopefully don't suck the dirt from the rag into the carb 1 Quote Link to comment
Motschrocker Posted May 28, 2017 Author Report Share Posted May 28, 2017 Still not having luck. I pulled the carb off the car and did a deeper clean of the jets. Sprayed through them with cleaner and some wire. I also pulled the plugs and they were black. I cleaned them up as well. It runs a little better but now i have to floor it to get consistent acceleration. It otherwise stutters and feels like it is missing. Not sure what to try next. Quote Link to comment
Motschrocker Posted May 28, 2017 Author Report Share Posted May 28, 2017 What do i need to adjust? Do i need to retard the timing? Quote Link to comment
racerx Posted May 28, 2017 Report Share Posted May 28, 2017 I thought u said u adjusted timing already and was good. If running rich, the carb needs adjustment. U running su Quote Link to comment
Motschrocker Posted May 28, 2017 Author Report Share Posted May 28, 2017 Its a knock off hitachi and yea the timing looks good to me. Ive adjusted the csrb every which way but still having issues. The car has idled alot while testing. Could that blacken the plugs. Could fuel be the issue? The fuel in the tank is from last fall. It sat all winter so its about7 months old at least. Quote Link to comment
spdcrazy Posted May 28, 2017 Report Share Posted May 28, 2017 vac leak at the base? I had a heck of a time with mine. 1 Quote Link to comment
racerx Posted May 28, 2017 Report Share Posted May 28, 2017 It stutters cuz ur plugs r black, need to be cleaned so that sparks have a good path. Quote Link to comment
Motschrocker Posted May 28, 2017 Author Report Share Posted May 28, 2017 Cleaned the plugs already with about the same result. Sprayed some carb cleaner by the gaskets and im not detecting any vac leak. I could try a different set of plugs. Quote Link to comment
spdcrazy Posted May 28, 2017 Report Share Posted May 28, 2017 what plugs are you running? gap? what ignition system? Quote Link to comment
racerx Posted May 29, 2017 Report Share Posted May 29, 2017 Same results with plugs cuz you did not lean adjustment. When u said that you adjusted the carb, which way did u go? How many turns? Quote Link to comment
Doctor510 Posted May 29, 2017 Report Share Posted May 29, 2017 You may have a hidden vacuum leak, take the vacuum line off the diaphragm unit and plug the line. If the unit will not hold vacuum, the diaphragm is broken and leaks. Quote Link to comment
Motschrocker Posted June 11, 2017 Author Report Share Posted June 11, 2017 Never would have guessed it and I feel silly. Turns out the issue was a wire off the alternator had come off. The wiring is a bit of a mess in the car and I didn't notice it at first. Crazy. I hooked it up fired up the engine and let it warm and before you know it I was cruising down the road with all the power she should have. Quote Link to comment
hang_510 Posted June 11, 2017 Report Share Posted June 11, 2017 ...when you think its fuel, its electrical. Quote Link to comment
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