1986 N/A FC

Shortly after buying my FC in April I visually noticed 1 of the 4 meterng oil lines did not have oil flowing through it. I started premixing as a precausion and then parked it in the garage when the weather got nice enough to drive the Z every day.

First I swapped out the pump with another I had lying around but the problem persisted. I drove it for a few hunderd miles and still no oil flow.

Now I have taken off the upper intake manifold and removed the oil injector nozzel. (see attached pics) I can easily blow air through the oil nozzel so I do not believe that is the issue. Beyond that what could it be? Clogged oil line? Weak vaccum source on the nozzel?

There can't be much to the s4 metering oil system. Am I missing anything? I want to make sure I correct any POSSIBLE issues before I put it back together.

Thanks,

Steve

 

I would just replace the line. I bet there's a small leak at one of the fittings, making any decent suction/pumping/pressure impossible. You know how screwed you are if the straw you are drinking Pepsi with gets even a tiny crack in it... Time for a new straw.

Either way, I've got a spare you can have. You'll have to come down, and while you're at it--check out the latest collection of FC's, lol. I've got a day off tomorrow, so let me know mang.

 

It's always possible that THREE DOLLAR BILL rebuilt the engine or his brother in law did, and instead of using a gasket on the front cover, he used RTV in lieu of the gasket. The RTV blocked the oil feed hole on the left side of the front cover and therefore you have no oil supply to the OMP.

OR, try this first. Remove one of the lines AT the OMP. It's just a 10mm banjo bolt. Now start the engine and get it fully hot. Hold the rpm at 2000 rpm while at the same time lifing fully up on the OMP rod AT the throttle linkage. Oil should pour out of the hole left by the removed banjo bolt. Well not pour, oooooze out would be a better term. IF it does, then the front cover idea suggested above is ...................not the cause. Write back and tell us what happened.

OMP don't fail unless they've been taken apart and screwed up on reassy.

 

make sure the banjo bolt on that line in the OMP is in tight and everything. mine was stripped and someone put teflon tape on it to tighten it up a little.

also might be a clogged injector. (seems more likely)

 

take the car for a ride, crack the line off start it up and see if it leaks out (with the revs at 3k)

I would suggest a new line and possible new injector.. I may have an injector if u need one Ipulled mine to premix the car had 75K when I did

 

i didnt see that you had already blew through it. by nozzle do u mean where the "vacuum line" hooks up? just to clarify there is no vacuum on that side. its a filtered air line.

 

yeah the air line is hooked up to the TB and the air source is before the throttle plate.

 

IF the air line was clogged..........the injector would inject a lot more oil than required. Just FYI. Like I say just remove one any one of the banjo bolts on the OMP and start the engine up. Oil should come out the hole on the omp especially If you manually raise the omp lever AT the throttle body while maintaining a fairly high rpm.

At idle, little to NO oil is injected so be sure to LIFT the omp rod when doing that.

The LUBRICATION section of the FSM shows how to tell if a omp is delivering enough oil. Somewhat as I suggested but collect the residue coming out of the omp in a give time frame.

 

Erik, the previous owner who installed the engine bought all bran new OEM oil lines. They appear to be in great shape but I was going to take that one off to see if there were any problems. I'll come down tonight and grab a spare though.

 

The engine was rebuilt by the Engine builder for Atkins Rotary and used in his own personal car before it was installed in my car. The engine has 25,000 miles on it and frankly is the strongest NA rotary I have ever experienced. I don't believe anything was messed up on the rebuild.

Both OMP's I have tried were in great working order as far as I can tell. I have vast experience with these and 3 or the 4 lines are getting oil flow.

 

Remove all that clear aquarium air pump line from the engine. Those lines collaps after they heat up and vacuum is applied to them. Not saying thats your issue since the OMP pumps fluid through the lines.

 

This I did not know. Good info.

Yes the oil injector nozzel is what I was refering to when I said I could blow through it. I was expecting this to be clogged and be an easy fix, but no dice.

 

I am very suspect of these guys. I am going to buy some silicon hose and replace those. Not sure who did that.

 

****Both OMP's I have tried were in great working order as far as I can tell. I have vast experience with these and 3 or the 4 lines are getting oil flow.
************************************************** ***********

Missed that when I scanned the thread.

If you can blow thru that injector from the nipple towards the engine but can't suck in the other direction, that's of course good.

If you can blow thru the oil line from the injector to the omp.........that's good.

How about swapping the injector with one that is flowing oil and see if your problem travels with the swap? And while swapping the injectors, looking down in the bore of the injector to see if something is blocking the entrance to the inside of the rotor housing. Crud in the small hole is what I mean.

Or how about swapping the oil lines AT the OMP to see what happens? Swap a *performer* with the non performer. Lines might reach from one banjo to another....maybe.

 

Thanks for the suggestions. I am going to take the line off and make sure there are no cracks and try some of the suggested things above.

I shined a light down the "bore" on the rotor housing and could not tell one way or another if there was an obstruction. Nothing obvious but its not like I was stairing at a apex seal or anything.

 

About the injector bore being clogged...........this idea is a bit of work. Get a piece of vacuum line a foot or so long. Attach it to the suspect injectors top nipple.

The hose that WAS on top of that injector goes to the spider with the other three air hoses. So put a bolt in the end of that one so it won't cause a vacuum/air leak.

Now route the NEW hose somewhere that you can get to its open end once the intake has been reinstalled.

Start the engine. As the car idles, feel the open end of that NEW hose and feel for vacuum. Vacuum should be there. It's the suction of the rotor on the intake stroke. No vacuum? Either the injector is clogged or the tiny hole doen in the bore for the injector is stopped up.

The bad part of this is you have to take the intake back off and remove the NEW vacuum hose and reinstall the original hose from the spider.

On one of my car I installed the spider on the firewall. The four lines to the oil injectors are just long. Much longer than stock. Anyway anytime I want I can idle the engine and while at idle remove any of the four injectors air hose and feel for vauum. Always have vacuum from the injectors. I'm not really sure why I did this on that car. It;s been a few years since I did that.

Back to the other ideas mentioned. Personally I'd remove that banjo bolt for the bad actor and rev the engine and see if oill is ooooozzzzing out of that bore or not. I can't see now it could not be coming out that bore and coming out the other three. Odd indeed.

Keep in touch and let us know what caused the problem.