Engine Burning a Lot of Oil

[beatnavy]

The next chapter (or saga) in restoring the '72 914 I found this summer:

I was finally able to get the engine started after 12 to 15 years of sitting in someone's barn and yard. I've replaced all the fuel lines and vacuum lines, reconditioned the injectors, installed a reconditioned ECU, and changed all ignition components. Once the rebuilt fuel pump arrived this weekend, I knew I had everything I needed. Sure enough, I was able to get the engine firing and running on Sunday, but very roughly with lots of junk and smoke spitting out the tailpipe (smoke everywhere!). I guess that's to be expected with a car sitting that long. This morning I discovered the #1 and #2 spark plug wires were crossed (that will explain the rough running), and I was able to get it running to something approaching an idle after it warmed up a bit, with less crud spitting out of the tailpipe. I like that throaty exhuast! The problem is that it is still spitting out a few oil particles and LOTS of smoke. I've probably only run it 5 minutes total now, as I didn't want to smoke out the neighborhood too much. I managed to put it in 1st gear and drive it back into my garage (although the engine wanted to die each time I put it in gear). So after 10 weeks of work, I've finally driven it 20 feet!

It's a '72 1.7L with stock FI. As mentioned, I pretty well replaced the ignition and fuel systems completely. I have not attempted timing (static or otherwise), but I have changed the oil. When I originally brought it home, I poured a little oil/Marvel Mystery Oil in the spark plug holes to try to lubricate the cylinder walls after all that time sitting in one place.

MY QUESTIONS:
Before I a) look to rebuild/replace the engine (arg!), or b) at least assume a ring job is necessary, is there anything else I should check or do? Should I run it a little longer hoping valves or rings seat better? Or is there something else I can check?

Thanks for everyone's help.

[Dave at Pelican Parts]

I'd say run it a while and see if it starts clearing up. You already put oil into the chambers, and it might take some time to burn off. And oil that has made its way into the exhaust will take still longer.

Run it for a half-hour or so, if you can stand it, and see if it's still smoking.

--DD

[NORD]

I'd say run it and see if it clears up. When you open the oil fill cap, how much blowby is coming out the cap? That is a way to tell if there is a lot of blowby past the rings.

[beatnavy]

Thanks Dave, thanks Nord. I managed to find some time after work this evening to try run it as you suggest. It's cold out now (mid thirties), and it takes me a while to get it started (pushing gas pedal, cranking quite a few times). Once it gets started, I have to keep a close foot on the pedal as the engine wants to die until it warms up some, then it idles high, at about 2,000 RPM.

I ran it for about 10 minutes before I thought the neighborhood might get annoyed with the noise and smoke. I'll keep trying to find time to run it, maybe up and down the street where the smoke can dissipate a little better, and see if it starts to clear up.

Nord, I opened up the oil filler cap while it was running, and I didn't obviously see oil spittle coming out of there (held a paper towel over it). There is still oil spittle coming out of the tailpipe. Either getting by the rings, leftover from what I put in initially, or both.

I know I still have timing and a couple vacuum issues to deal with, and I'm sure after all this time the MPS and CSV may not be serviceable. I guess I need to start looking at how to get a smooth start up and idle.

[NORD]

Probably won't see oil spitting out but may be able to feel a lot of blow by pressure coming out of the filler cap. Check that. Hope it clears up for you

[Nostril Cheese]

Do a compression check.

[beatnavy]

Awesome, thanks for the input. It's Saturday, which I means I have time to work on the car, and I have some "new data" that might be helpful.

I replaced most of the rubber vacuum elbows, including the big one attached to the throttle body, the one at the PCV valve by the oil filler neck, and one that connects to the manifold from the PCV valve. Vacuum situation is probably still not perfect, but it has to be better. I also made sure the connection at the cylinder head temp sensor was good and clean (that's the sending unit near cyclinder #4, right?). Here are my results (I had the air cleaner removed during all of this):

I got the car started and took it for my first drive around the neighborhood. I'm actually very impressed with the low-end torque and handling. It IS fun to drive, and I found no obvious issues with the drive-train, suspension, or handling. Yay! During the process of getting it started and driving it around, it went through three almost distinct phases:

1. Starting and initial warm-up. Still VERY hard to get started, and you have to give it some gas and crank several times. Once it starts, it REALLY wants to die every few seconds, and you have to keep your foot on the pedal to give it more gas to keep it running. BTW, it's in the high 40's outside right now.

2. Initial Stable Operation. After the first two minutes, it seemed to stabilize, idle nicely at about 1200 RPM, and I didn't see much if any smoke coming out of the tailpipe. I thought "I'm good!"

3. Further Warming. After about five minutes (complete guess), the idle then climbed back toward 2000 RPM, and it started smoking again. Not nearly as bad as initially reported, but still leaves a little bit of a "trail" as I drove it around. Again, the engine felt pretty solid, just idled high. If I cranked the throttle body screw all the way down it took it down to about 1700. If I pulled the vacuum hose at the PCV valve, the rubber elbow closes up on itself from the vacuum and the RPM's also drop a 100 or 200 RPM. When I shut the car off, I noticed a lot of smoke coming out of the blower motor assembly (probably just old crud burning off inside the heat exchangers, right?). The car does start more easily when warmed up.

Nord, I definitely feel some air moving around from the oil filler cap, but I honestly don't have anything to compare it too, so I can't characterize it very well. I don't see significant "spittle" coming out anymore. Nost. Cheese, I did do a compression check when I first brought it home in August. Cyl 1, 2, and 4 seemed to check out within tolerance. For whatever reason, I could not, for the life of me, get the instrument to thread into Cyl 3 (even thought the spark plug is in there ok), so I don't have a reading there.

I'm trying to use Anders' D-Jet Troubleshooting Guide, but if, based on this info, you can help me narrow down the search in terms of better starting, less smoke, and lower idle, that would help greatly. I still haven't attempted to adjust or check ignition timing or do valve adjustments. Could the car be running much too richly after warm up? Would that cause smoking as well?

[wndsnd]

I just went through the same but I found my issue with my new carb set-up.

It would idle and run fine and then after I drove down the street, it would race around 3000 rpm.

I was going crazy, checking distributor advance, vacuum leaks at the carbs, Throttle cable, linkage, ball joints.

Make sure your throttle cable is not wrapped around the clutch cable.
You will need a little mirror and I found it was best to back light in the tunnel from the Shift Rod opening. I have a little flex shaft flashlight that I put in from there and aimed it to the front of the car. Then reach in with your mirror from the front where the linkage enters the tunnel at the belcrank. You will need to be a contortionist, but it is good to clear up the cable wrap possibility.
You can also push in the clutch while running and see if that effects your idle.
If it does, that is another indicator that the cable might be binding.

My engine just returned from the dead as well, and I have to say it smoked quite awhile. I would say it cleared up after 1/2 hr or so of tinkering and running.


There are a lot of good injection mechanics on the board, you will get better answers from them re vacuum leaks, pcv, and other injection related issues.

Good luck!

John

[Nostril Cheese]

Originally Posted by beatnavy

Awesome, thanks for the input. It's Saturday, which I means I have time to work on the car, and I have some "new data" that might be helpful.

I replaced most of the rubber vacuum elbows, including the big one attached to the throttle body, the one at the PCV valve by the oil filler neck, and one that connects to the manifold from the PCV valve. Vacuum situation is probably still not perfect, but it has to be better. I also made sure the connection at the cylinder head temp sensor was good and clean (that's the sending unit near cyclinder #4, right?). Here are my results (I had the air cleaner removed during all of this):

I got the car started and took it for my first drive around the neighborhood. I'm actually very impressed with the low-end torque and handling. It IS fun to drive, and I found no obvious issues with the drive-train, suspension, or handling. Yay! During the process of getting it started and driving it around, it went through three almost distinct phases:

1. Starting and initial warm-up. Still VERY hard to get started, and you have to give it some gas and crank several times. Once it starts, it REALLY wants to die every few seconds, and you have to keep your foot on the pedal to give it more gas to keep it running. BTW, it's in the high 40's outside right now.

2. Initial Stable Operation. After the first two minutes, it seemed to stabilize, idle nicely at about 1200 RPM, and I didn't see much if any smoke coming out of the tailpipe. I thought "I'm good!"

3. Further Warming. After about five minutes (complete guess), the idle then climbed back toward 2000 RPM, and it started smoking again. Not nearly as bad as initially reported, but still leaves a little bit of a "trail" as I drove it around. Again, the engine felt pretty solid, just idled high. If I cranked the throttle body screw all the way down it took it down to about 1700. If I pulled the vacuum hose at the PCV valve, the rubber elbow closes up on itself from the vacuum and the RPM's also drop a 100 or 200 RPM. When I shut the car off, I noticed a lot of smoke coming out of the blower motor assembly (probably just old crud burning off inside the heat exchangers, right?). The car does start more easily when warmed up.

Nord, I definitely feel some air moving around from the oil filler cap, but I honestly don't have anything to compare it too, so I can't characterize it very well. I don't see significant "spittle" coming out anymore. Nost. Cheese, I did do a compression check when I first brought it home in August. Cyl 1, 2, and 4 seemed to check out within tolerance. For whatever reason, I could not, for the life of me, get the instrument to thread into Cyl 3 (even thought the spark plug is in there ok), so I don't have a reading there.

I'm trying to use Anders' D-Jet Troubleshooting Guide, but if, based on this info, you can help me narrow down the search in terms of better starting, less smoke, and lower idle, that would help greatly. I still haven't attempted to adjust or check ignition timing or do valve adjustments. Could the car be running much too richly after warm up? Would that cause smoking as well?

Ignition timing and valve clearance are the first things you should check before anything else. They do have a effect on getting the injection working right. The fuel injectors are timed off the distributor. Incorrect ignition timing will affect idle speed. On your car, timing is 27dg. BTDC.

Double check that you have the vacuum lines hooked up correctly. There are diagrams on this site. Also check that the boots going between the plenum and runners are in good shape. How are the gaskets at the heads? How are the fuel injector seals?

The MPS has the biggest effect on mixture. If they start to go out, they can cause a really rich running engine. Check the manifold pressure sensor (MPS) on the passenger side of the engine bay. Grenade looking thing. One one end, there should be a epoxy plug. Has it been drilled though? Take the vacuum hose off the MPS and suck on it. Does it hold vacuum? Look at the troubleshooting guide and check resistance on the terminals.

Check the fuel pressure. There should be a port off the driver's side fuel rail to attach a gauge. Should be around 27-30psi. Id check to see that the fuel pressure holds, with the engine off for 30 seconds or so. If it does, check pressure with the engine running. Does it fluctuate?

I'd also check operation of the Aux. Air Valve. This has a hose going to the rubber intake boot. Turn the ignition on (dont start the engine) and blow through the hose. You should be able to blow through it. After a couple of minutes, try again. It should get harder and harder to blow through. The idea here is to provide extra air when cold until the engine warms up, then it closes. Does it close?

Oil burning.. Have someone rev the engine and see if there is oil flinging around the front of the engine, both from the top and bottom.

[beatnavy]

Great, thanks to everyone for their continued help. Here's my update at this point:

I did get the dwell and timing adjusted on Saturday afternoon, and it runs pretty well after warm up. The good news is that the smoke, to a great if not complete degree, has cleared up! I'm very happy about that. Based on troubleshooting and reading I am narrowing in on the Aux Air Regulator being stuck open as at least one likely suspect in the very difficult warm-up and high idle. I do want to make sure I'm testing it correctly: Nostril Cheese, when you say blow through the hose at the AAR do you mean the one connected to the deceleration valve?

I think adjusting the valve clearance is also an excellent idea, and that's probably going to be my next maintenance item to check. There is no hole in the MPS epoxy, but I have not yet tried to see if it holds a vacuum. I'll check the resistance this week.

Wndsnd, thanks for the tip on the clutch/throttle cables. The pedal does feel "sticky" and it doesn't seem like it's at the linkage. I don't think that's the source of the high idle, but I do think something is probably binding the cable. I may have moved a cable when I was working on the brake lines and fuel pump.

Thanks!

[Dave at Pelican Parts]

For the sticky throttle: Isolate the problem. Disconnect the cable at both ends. Work the cable with your hand--does it stick? Work the pedal by hand. Does it stick? Work the throttle valve with your hand. Does it stick?

If the answer in all of those cases is "no", then hook the cable to the throttle valve and work the whole thing by hand. Does it stick now? If not, unhook it from the throttle and hook it to the pedal. Sticky? Try to isolate the problem.

I don't remember exactly where the decel valve is on the 1.7 motors, but the AAR lives to the left-front of the manifold. (AKA plenum or intake air distributor.) It has one hose that goes to the intake boot, and one that goes to the manifold at the same place the cold-start valve plugs into. Check the "EFI Hose Diags" in the 914 section of the main page to see what I mean.

The AAR should allow air to pass through it when at room temperature (broadly defined), and after the engine has been running 5-10 minutes it should close up so you cannot blow through it.

If the valve in the AAR is stuck open, you will get an OK idle when cold, and a high idle when warm. That is the most common failure mode of the AAR. If it is stuck closed, you will have a very low idle when cold, and a good idle when warm. (Note that monkeying with the idle bypass in the throttle body can move idle up or down, warm or cold.) The other failure modes include the valve taking 15-20 minutes to close because the heating element has failed and just engine heat is what is closing it, and constantly blowing the fuel pump fuse because the AAR power wire (which is shared with the fuel pump power wire!) is shorted to ground.

--DD

[beatnavy]

Thanks for the help. This week I confirmed that the AAR was stuck open. I managed to get inside of it and free it up (it was REALLY stuck) following various guides and instructions on the topic on this site. Now I do think it's actually moving and operating as normal. Once I get the new valve cover gaskets I'm going to adjust valve clearance.

But now I have another problem that may or may not be related -- the engine simply dies when it starts reaching operating temperature. I will start a new thread on that topic.

914: It's my gift that keeps on giving...