So my rebuild had a big breakthru last night. I finally managed to get the car to start. Unfortunatly, i only made this happen by pouring oil down the carb. Without it, and after the car would theoretically have burned through the oil dumped, it will die and or not start again. Is this an OMP issue? Whats going on? Ideas?

Also, the car smokes like a bat out of hell when it is running. Like to the point i couldn't see down the street lol. The smoke almost completely disapears if the car is held at about 2500-3k rpm but is thick and ridiculous at any lower rpm.

Also the car wouldnt idle after it was warm. Could this be a timing issue since I havent timed it yet?

The car is a 1984 GS 12A

 

i have an 82 gs that sat for 2 yrs and i was told to do this to the carbs before turning over the first time to lube the apex seals. she started right up. how much oil did you put in there? it should only be from a few drops to an ounce. also it should quit smoking after 10-15 mins. not sure about the timing though.

 

Yeah it only ran for about 5-10 so im not too concerned about the smoke yet. Lubing the seals makes sense, but shouldnt the OMP take over the work after it starts?

 

Sometimes those seals stick after sitting for so long and take alot to unstick... Try some seafoam through the engine if you can?

 

Should they be sticking in a freshly rebuilt motor though? I cleaned out all the carbon I could from the rotors.

 

Correct timing is very important. If timing is off enough it will not idle. If its off too much it won't even start.
Check out this thread.
https://www.rx7club.com/1st-gen-archive-71/ignition-main-pully-timing-525909/

 

I did the whole line up the marker pulley and install the distributor bit correctly I know. The car would run fine at 600rpm or above but if i brought it down too low (around the 300 marking) it would sputter to a stop. I'm thinking maybe i just need to adjust the idle screw and fine tune the timing.

Any ideas with the OMP stuff? Should I just pull the lines after the car is warm and see how much they are putting out? Should I just keep putting oil in the carb and see if eventually the OMP will start it without the extra oil in the carb?

 

Did you replace the oil control o-rings and thier carriers? My first rebuild was a test to see if I could do it and what problems I might run into. Only new parts were the gasket kit. The oil control o-rings were so worn that I went through 6 qts. of oil and 5 gal. of gas. The neighbors came over cause they thought the garage was on fire.

Add some pre-mix to the fuel tank. If that doesn't help with building compression for starting, then you have too much fuel and it's washing down the combustion chambers. reducing compresion to the point it won't start. Did you do any porting? If so, it's possible that you ported too far allowing oil to bypass the ontrol rings.

When I do a fresh rebuild, I use lots of assembly lube that's less susceptable to fuel washing.

There's no reason for you to have the engine idling below 600 ppm, Get the timing set at 750-800 rpm, then turn the idle screw up to 2k and let the engine run at that rpm for 20-30 minutes for breakin, keeping a close eye on temp and oil pressure.

Please list what parts you replaced during the rebuild any mods, particularly porting and post pics of that if you have any, also whose template did you use .

 

I'm fairly sure you won't get any rotary to idle well (if at all) at 300rpm. That's only 5 shaft rotations per second. These engines are pretty low-mass; not a lot of stored inertia.

 

I purchased the Master Rebuild kit from Atkins. I replaced all the gaskets, the oil filter, side seals and springs, apex seals and springs, oil rings and the inserts, front and rear main seals, oil pump chain, needle bearings, and the corner seals and springs. I didn't do any modifications to the motor dispite my temptations lol.
I also replaced the oil (20W-50), the coolant, the radiator, the water pump, the coolant temperature sensor, and a vacuum delay valve that i snapped when removing the engine.

I should also mention that my exhaust is shot and the pipe between my last catalytic converter and my muffler over the axle pipe is broken straight off. I don't think this should make any real difference with the back pressure since it ran like that before the rebuild. I'm getting a new exhaust soon as it is.

The engine idled here:



when it was warm before the rebuild. So I should set it so idle at about 750rpm when warm now?

 

Yeah, she should idle around 750 rpms. Then head over to www.sterlingmetalworks.com and read the article on "Idle Tuning" to get the carb set. Then check your timing.

Try starting it with Seafoam instead of oil, then do what Trochoid said in regards to breakin.

 

Only problem with the premixing bit is I have no idea how much gas is actually in the tank at the moment. Could the same thing be achieved by just continuing to dump oil down the carb?

Oh I should also mention that yesterday when i started the car to run it a bit, i noticed that the engine temp was normal but the oil pressure was steady at 15 and not budging no matter the revs. I shut the car off to discover the fitting for the oil return line from the oil cooler to the front cover, the fitting on the front cover, was leaking badly. How do you tighten that fitting exactly?

 

with a box wrench. you may need new crush washers you can get them at napa. anyway clean the oil up, turn the car on and tighten till theres no more oil leaking.

 

Last thing you need during break in is an oil leak. It doesn't take long to chew up the bearings in rotors and stationary gears, learned that one the hard way. When I lost all the bearings on my first rebuild it was due to a simple assembly error. I forgot to install the o-ring between the front cover and the front iron. Which resulted in no oil pressure and the loss of all 4 bearings and the e-shaft, in just 6 hours of run time. Had I not used copious amounts of assembly lube, the engine would have siezed long before that.

Next thing to do is go over every connection, vacuum, electrical or otherwise on the engine. Does the choke work? When cold, the **** should stay out when pulled out until the engine reaches operating temp. If not, it's either not hooked up correctly or the #2 temp sender on the backside of the water pump housing is either not plugged in or one or both of the wires coming from it are broken.

Once the engine is warm, turn the idle screw up to 750 rpm and time the engine. Correct timing is critical for break in as is fuel mixture. If you didn't rebuild the carb, you should have. Too lean of a fuel mix creates hot spots, too rich leads to excessive carbon buildup.

I would also drop the oil viscosity rating down to 10W30 for break in, no need for the 20w50 during break in. The purpose of break in is to allow the parts to wear themselves to each other for better mating/sealing.

 

Well I dumped some more oil in the carb today and fired her up. Changed the idle to roughly 750rpm, and let her run for a while. I dumped a little oil into the carb during the break in just to be safe. 10 minutes later all signs of smoke are gone and the car is idling smoothly right at 750rpm. I figure a couple more days of break-in and the car will be ready for the road at this rate.

I also fixed my oil leakage on the front coupling so all the gauges were reading normal. Only thing is I have to pump the **** out of the pedal to get it to start. Should this improve with time after the break in you think? The engine was warmed up, and no choke, but a lot of pumping and it would fire up. Havent tried to start it again since. Gotta add more coolant first =D

 

Check the timing. Also, in regards to setting the idle and tuning the carb, read up at www.sterlingmetalworks.com

Lots of info there.....

 

i'm glad you got it sorted out. however, i do think it's funny that you can rebuild your engine and didn't know it was supposed to idle at 750 rpm . and i'm not meaning to offend you nor anything, i just think that's a funny.

 

thats weird I've seen my fb idle at that mark :|