Glazedham42

iTrader: (4)

Hey guys. I’m very close to being done with this project car, but I am about to go crazy right now. I don’t think that the engine is running right, and it is giving me fits trying to figure out what is wrong. I am so fed up with it, that I have heavily considered selling it a couple of times recently. It is missing and sputtering quite a bit at idle, and it does so more and more as you rev it up. It misses so bad in the higher revs that I can’t even get past 6000 RPM. When you start to rev it up, it bucks and misses and spits and shakes rather violently. I know that I should expect a few blips in the throttle, but this thing isn't smooth at all. Rotaries are supposed to be smooth!! The engine shakes and quakes and rattles for no apparent reason. It isn’t burning or leaking any oil or coolant, so everything is okay in those departments. I am wondering if I have a bad apex seal, and the poor compression is causing some “blow-by” into the next rotor face. I don’t know if this is common or not. I am just trying to think of every possible situation. To me the whole thing seems like an ignition problem, almost like it is misfiring. I’m not sure what “detonation” is either, but from some other descriptions I’ve read it may be that?? I’ve cranked the car without the plugs in, and it makes nice “PFFT” noises on the entire rotor faces. So from what I can hear the compression seems to be very good. I realize that I could try to explain my problem in numerous lengthy paragraphs, but I decided to put together a small video instead so you could actually see and hear the car running. Before you see the video, let me brief you quickly on the basic setup of the car just so we know what we’re up against.

The car is a 1985 GS with a 12A & 5 sped. manual tranny. It was originally a 4 speed auto, but I hated the auto so I swapped it out for the 5 speed. The original 12A engine in the car had been overheated several times before I purchased the car. This is not a good thing as we all know. The engine smoked a lot and I figured I would be better off to get it out of the car. I put a new engine in it that I got from a local junkyard, and it has about 90k on it. I am also using a racing beat light steel flywheel, with my old counterweight off of the automatic.

As far as fuel goes, I have pretty much replaced the whole fuel system. I cleaned and lined the inside of my fuel tank, replaced all my fuel hoses, and filter. I trashed the stock fuel pump, and I am using a Carter 5 lb. fuel pump instead. It works great and supplies plenty of fuel pressure at all times. I cleaned out the fuel supply line leading to the carb with compressed air. It has no blockages. I am running a Holley fuel regulator, to my Nikki carb. I regulate the fuel pressure at 2 psi to 2.5 psi. The Nikki was recently rebuilt by our resident carb. master Sterling. He removed all the emissions equipment for me, and I believe he also put in bigger jets. I am ignorant when it comes to the guts of the carb though. I am trusting his work on the carburetor because it worked great on the old engine. I have also capped off all the nipples on the carb spacer, and taken the butterfly out of the intake. I have new cork gaskets everywhere on the intake and carburetor that I installed with plenty of Hylomar gasket coating. I have replaced every inch of hose on the car, and have new clamps on all the hoses. I think it is highly unlikely for me to have a vacuum leak, but it could happen.

For air delivery I am using a chopped up stock air cleaner box, and a K&N filter. Nothing fancy, but it should be getting all the air it needs. Finally comes the ignition which I believe may be causing the problem more than anything. When the junkyard engine was delivered to me the timing marks on the front pulley were completely gone. The pulley was also pretty rusty, so you couldn’t really even see the indentations where the paint marks were supposed to go. After cleaning it up quite a bit I made some comparisons between the pulleys of my old engine and the new one. I noted the configuration of the front bolt pattern on the pulleys and matched them up as close as I could. Through this method I believe I was able to find the timing marks on the new engine, by comparing to the old one. I am 98% sure that the marks on my pulley are correct. I hate to rule anything out though. I replaced the stock spark plug wires with a nice set of Accel wires. They are the ones that you have to cut to the correct length and then attach the ends yourself. I’m wondering if there is a chance that I screwed it up somewhere and the wires are causing a misfire. This is the first time I’ve made my own plug wires, but I followed the directions on the box. I don’t believe this is likely, but I’m not ruling it out either. I’ve got four brand new NGK BR8EQ14 spark plugs in the engine. I guess I could wire brush them off a little bit, but I don’t think they are the problem. I have replaced the old coils with two brand new MSD Blaster 2 coils.

The dizzy has a brand new cap and rotor. I have noticed however, that there are significant grooves on some of the pickups inside the dizzy cap, while others show no wear at all. Also, I have left the vacuum pots on the dizzy uncapped. I don’t know if this is correct or not but it is what I have done. Also, I have the little black bullet plug by the dizzy unplugged. Is this the vacuum advance?? I still don’t know anything about vacuum advance, so I may be making some mistakes as far as that is concerned. I installed the dizzy into the engine exactly like the Haynes says to. I aligned the leading timing mark on the pulley with the indicator pin. Then I lined up the indentation on the dizzy shaft with the indicator notch. After doing this I dropped it straight into the engine. Checked the timing and both my leading and trailing marks were right on. The car was still running like crap though. At first I thought that I may have screwed up the dizzy installation. I wondered if I was off by a tooth one way or the other. But since then I have re-installed it probably ten times just like the Haynes says, and I get the same results every time. The car sputters and misses every time I start it. I’ve wondered if I have a bad igniter, which I’m guessing is a distinct possibility, but all four of the spark plugs are still firing. I put my timing light on any one of the four plug wires as a method to check for spark, and the timing light will flash on all four of them. I’m assuming that this means they are all getting spark. Is it possible for an igniter to work intermittently? I have also heard about the timing being 180 degrees off. I would’ve thought that out of the ten times I installed the dizzy, I would’ve gotten it right at least once. Or does it not work like this??

I’m also getting a lot of smoke while it is running, but like I said, it doesn’t burn ANY oil or coolant. I think the smoke is just coming from my unacceptably rich premix that is in the tank. I think I need to add about 5 gallons of straight gas to thin out the premix mixture. Also, the car doesn’t like to idle below 1000 RPM. Is this because I have the Racing Beat steel flywheel? I don’t think this is the case, but the engine hates being below 1000 RPM. It starts shaking and missing like there is no tomorrow. The rebuilt carb always allowed my old engine to idle smoothly all the way down to 500 RPMs. I really think it all goes back to the ignition.

Now that you have learned all about the car and my setup HERE IS THE VIDEO!!!! I have uploaded it in quicktime format. Hopefully you guys will be able to view it. If not, you can download quicktime for free from Apple’s website. Listen very carefully to the way the car sputters at the very beginning of the video. This is what I am talking about. You will hear it miss and sputter through the exhaust better than any other time in the video. When the car is revved up it makes a constant "buh-duh-duh-duh-duh-duh-duh" through the exhaust. This is not natural, and it makes the engine shake when this happens. Watch how the engine shakes and misses when it is revved up....


RIGHT CLICK HERE, "SAVE TARGET AS" TO WATCH THE MOVIE!!!

This whole thing just has me angry and confused right now. I know that this is the best place to get help with a problem, so here I am. Please watch the video if you are able. I know some people still have dialup like I do, so I understand if it is too much to download. The video is 16MB, and is about 1 minute long. It’s not monstrous, but it is rather large. If you have any suggestions or questions at all PLEASE FIRE AWAY! I’m ready and willing to answer.

IF ANY OF YOU ARE LOCAL TO ME AND WOULD BE WILLING TO COME TO MY HOUSE AND HELP WITH THE CAR SOME WEEKEND YOU ARE MORE THAN WELCOME!!! I WOULD APPRECIATE SOMEONE TO HELP ME TROUBLESHOOT THE CAR, AND FIND OUT WHAT IS WRONG!

Glazedham42

iTrader: (4)

Here are some pictures that will provide a little better visual for you than the video does....

Glazedham42

iTrader: (4)

Some more pics...

Glazedham42

iTrader: (4)

Anyone? Have you guys even bothered to read the novel I just wrote...

satoacs

....im scared

txredneckmedic

Ummm...maybe plug that mysterious wire into the black wire??

Rusty Shackleford

the mystery wire if im not mistaken does either coolant level or temp..not 100% i have seen it though the dizzy should be T's and run to one of the openings on the carb i think first...

does the wires coming off the dizzy going to the coils have to be in any order maybe switching those??? or checking the plug wires for the right wire to plug...

mar3

iTrader: (8)

I, too, am scared to follow the "Save Target As" advice to see the movie...


Re: Two of your pics...




There should be a condensor screwed onto the distributor body or near the distributor body that the black wire goes to...






Coolant temperature sensor....should be screwed into the block under the beehive cooler mess, thereabouts...oil pressure is a flat head connector...

cdrad51

Too tired... I'll answer tomorrow.

13B4port

try maybe retarding the timing some, also try unhooking the vacum advance on the dizzy, try more fuel, try less fuel. check all the little things.

Rusty Shackleford

the movie is fine to download....isnt this a rebuild engine??? because i have eben following your rebuild since the start...and shouldnt the engine be broken in first to settle the seals and once everything is set then it will run alittle smoother..?

Glazedham42

iTrader: (4)

The engine is not a rebuild. It's a fairly low mileage one that I got from a junkyard in Ohio. The engine has about 90k on it, and looked like it had never been tampered with before when it arrived. It still had factory NGK plugs in it, and all the stock parts were still installed on it as a longblock. I find it hard to believe that it has a bad apex seal. I wonder if it has a little carbon buildup and I just need to blast it out?? I've thought about steaming the engine also to see what that would do for it.

13btnos

iTrader: (1)

Check your timing from the picture of the distributor and the position of hold down bolt for the distributor, in reference to the distributor, it looks to be a bit retarded. Timing light will remedy this or do it by ear, works for me, advance it a little and and see if there are any changes in the motor. Check for vaccum leaks a can of carb spray will help. Spray carb cleaner anywhere you think you might have a leak and you will have a change of tone in the motor when you find a leak. Hope this helps out a little. And since this was a junkyard motor do a compression check on it. Just because it appears to be good on the outside doesn't mean it's good on the inside. A compression test will tell you alot about the condition of the motor.

lovintha7

fuel pressure looks a little low. I think Nikki's run at around 3-3.25

Glazedham42

iTrader: (4)

Please don't be scared to download the video guys. I promise you it is okay.

I've tried a few things and here is where I currently stand.

1) I plugged the black wire into the condensor on the dizzy body like suggested. I thought this was where it was supposed to go. I noticed no change after plugging it in, however it is now connected as suggested by Mar3.

2) I'm not sure about the fuel pressure setting. I have always known Sterling to recommend a fuel pressure of 2-2.5. I wondered about the fuel pressure myself and I have tried settings from 1 psi all the way to 5 psi. I haven't noticed much of a change with any of these different fuel pressure settings.

3) I sprayed most of the things in the engine bay with carb. cleaner and didn't notice any difference in the condition of the engine. This leads me to believe that the problem is not a vaccuum leak. I didn't really think that it was anyway, but this confirms my suspicions even more that it is an ignition problem.

4) I have tried setting the timing with a timing light and even when the light shows that the timing is dead on, the car still runs like crap. I think I'm going to try setting the timing by ear and forget messing around with the light and the timing marks on the pulley. They obviously havent worked for me thus far, so I think I'm going to try and do it by ear and see what happens.

5) The brown mystery wire IS NOT for the coolant temp sensor. I already have that plugged in and it works fine. If anyone has an 85 GS I would appreciate them tracking down this wire and seeing what it is supposed to plug into. I can tell you DEFINITELY that it is not for the coolant temp sensor or the oil pressure bulb.

That is where I'm at right now. No new findings really, except that I'll probably try to set the timing by ear...

Keep the suggestions coming! Thanks a bunch so far guys....

gsl-se addict

iTrader: (3)

The brown wire should be for the coolant level sensor (on top of radiator).

Rx7carl

I'll get to the vid later.

1- are you sure the replacement engine is an 83-85? The counterweights would be different on earlier engines. I also hope you took care to heed Mazdatrix's advice regarding the front spacer and thrust bearings.

2- lots of hylomar? Your supposed to use this stuff sparingly, like a thin coat or paint. Any excess will squeeze out all over the place, including into your intake tract.

3- Thats an impossible way of indexing the pulley. The bolt pattern is symetrical. Ya cant do it that way. Only by the woodruff keyways is it possible to tell. I think theres a pic about that on my cardomain site.

4- the vacuum pots wont cause this, and the black wire is for the condensor, that shouldnt cause this either, its more for RFI supression so you dont induce ignition noise into the stereo system.

5- You have 4 possible ways of indexing that pulley, and its probably not an igniter from your description.

6- Hows your PCV setup?

7- Front coil is trailing, rear is leading, you do have that setup right yes?

Youll be getting a bill soon.

Rx7carl

Watched the vid. Sounds like an ignition problem. Possibly. Thats where Id start. Your 25% of the way to all 4 possiblities on the pulley. Oh and its not flooding is it?

The brown wire could be for the cold start assist bulb on the side of the oil pan.

cdrad51

Watched the video too. That was the kind of sputering I was getting when my carb was not jetted right, too big fuel jets, resulting in running excessively rich. Once I changed to smaller fuel jets, problem was gone. Check your spark plugs. Are they black? if so, you might be running too rich and either need to reduce the size of the fuel jets starting with the primaries, or increase the size of the air bleeds. My $0.02.

Glazedham42

iTrader: (4)

Cdrad, checked my plugs. They are all totally black. I do recall Sterling putting some bigger jets in the carb, just as a favor to me. You think this could be the problem? It seems to be running awfully rich, all of the time. It never floods, but it stinks and smokes a lot. What is involved in changing the jets? Is it hard to do? I don't have much exprience working on carbs really....

Carl, I'm positive that the engine is out of an 85 GS, so that eliminates some of the catastrophic problems that could happen.

cdrad51

Ok. Get from Sterling what size jets you have. Get also his recommendation on which to change to what size.

Changing jets on a nikki with no emissions crap is rather easy. I can help you when you get to that point.

cdrad51

Fuel pressure is fine.

steve84GS TII

First thing that popped into my head was your statement about the pre-mix.If your OMP is not working,youll need pre-mix obviously.But too much oil will cause a lean fuel/air situation.Its common to think,"more oil=rich" but its actually the other way around.
In a mixed state,the 2 cycle oil displaces an equal amount of fuel. An ounce of premix,mixed with given amount of air will be leaner than an ounce of reg. fuel mixed with the same amount of air.And since oil doesnt combust like fuel,it furthur hinders the ignition process.I work on 2-cycle equipment at work,and its a very common problem with homeowner's tools that come in for repair.
When I was running premix in my turbo engine for a while,it ran like sh*t when I went too heavy with the oil.Wouldnt boost up and it missfired a lot.After I got the OMP working,it went back to normal once the pre-mix was burned off.Rotaries need very little oil,WAY less than a chainsaw or weedeater.Those run about 50:1,a rotary takes something like 150:1, or something in that range.If the oil metering pump is hooked up and working,get ALL that premix out of the tank before you try more tuning.If the OMP isnt working,make sure its completely out of the picture,oil delivery-wise.Then get your pre-mix ratios under control.Do a search to find out EXACT pre-mix ratios that other guys have succesfully used.....

Glazedham42

iTrader: (4)

Steve,

I've also wondered about the extra oil in the premix causing problems, and misfires. I'm not running an OMP at all, but I can guarantee that my oil is mixed to every bit of 100:1, probably even stiffer than that. I accidentally dumped more oil in than necessary one day and have still been paying the price for it. I've heard most guys say that you want to mix around 1 ounce of oil per gallon of gas. Do you think this is about right, or still too stiff of a mixture? I've been using 2 stroke outboard boat oil in my premix, but I don't like the stuff very much. I'm thinking about using MMO as a premix instead because it seems to burn cleaner. Let me know what you think about this.


Cdrad,

I'll send ol' Sterling an email ASAP and find out what is up with the jets. Maybe I can figure out something from there. I might try thinning out my fuel first though, and see if that fixes my problem...

Glazedham42

iTrader: (4)

Ok guys. Here is a little update. I drained out all the fuel and refilled the tank with fresh correctly mixed gas. I used MMO as a premix this time, and mixed about 125:1. I took out all my spark plugs, and they were all completely black. I wirebrushed them off and put them back in. Started the engine up and it was still gurgling and missing like usual. It seemed to be a little bit better, but I'm not pleased with it still. I'm going to see if I can get some info from Sterling about my carb. jets....