engine and drivetrain Newbie with a tii...

[pilotnbr1]

Hi all, I have been a long time lurker on the forum and been watching for the right car to come along. 2 months ago I found a 74 tii down in Florida went and checked it out and made the leap!

The car had not been driven for a number of years and had already had the fuel system gone through by a pro. Tank boiled out, fuel lines changed, fuel pump changed, fresh filter. All but the KF injection pump and injectors. Everything else seemed functional and relatively rust free, minus brakes and clutch. After I bought the car I had the KF injection pump rebuilt by Fairchild Industries, which I highly recommend. After the rebuilt pump was put on by a shop in Florida they got the engine to start. At that point I was done with the shop and had the car shipped to my home in Atlanta Georgia.

Heres where it get interesting and I am open to all ideas and suggestions. Upon receiving the car it starts but only after some extended cranking and the gas pedal to the floor. Once it starts I have to hold the gas at about 4000 rpm to prevent the car from dying. After a minute or so of this it warms up and I no longer have to hold the gas pedal. Then as it further warms and rpm drops it dies abruptly at about 2500 rpm. When running at 4000 rpm it seems fairly normal with no smoke and a great sound! RPM lower than 4000 and you can feel some roughness.

Other problems are that something is creating smoke right below or at the number 3 spark plug(im thinking below as the wires are sooty and it doesnt smell or look like oil cooking off) and a fuel leak causing an accumulation in a nook of the transmission above the clutch slave.

The smoke and fuel leak I will track down with more time. It is the engine performance that I am hoping someone may have some pointers. I pulled the spark plugs and they are some variety of bosch platinums that seem incorrect with the number 3 plug oily and a gap of only 025 vs about 035 on the others. The wireset was in poor shape as well. I got some NGK BP6ES at autozone but they didnt have bosch or NGK spark plug wiresets in stock. So I was unable to try them on the engine. I know this is not alot to go on but was hoping you guys might have some ideas.

I have only had the car a day, and spent time getting the clutch back up and working so I could get the car up our sloped driveway and off the street. I would describe myself as a shade tree mechanic in terms of ability. Thanks for all the help and the education I have gotten so far!

[ray_]

Welcome!

Get rid of the platinum plugs, do a tune up and valve adjustment and compression check, go here are get this:

http://thetiiregister.com/kb/59

And then: http://www.bmw2002faq.com/content/view/66/32/

Read everything and come back. And then read http://my2002tii.com/

GL,

Ray

[dubois]

First you have to go back to basics: compression test, adjust the valves, points, condenser, get rid of your vacum leaks, etc, etc

The tii fuel injection system is an engineering marvel. It is actually very simple and very efficient. The injection pump is the black box, of the system, it is set at the factory or in this case at the rebuild. It can actually be fine tuned for your motor, but should be the last thing you should attempt. The rest of the system connects the pump to your air butterfly synchronizing air/fuel. This has to be correct, with no bindings or play. Idle speed is set by adjustments in this part of the system, which consist of a cam, and several linkages with screws that set the idle stop and full throttle stops. The third part of the system has to do when the car is cold. There is a cold start injector and it is controlled by a "computer", which shoots gas when the engine is cranked, there is a warm up regulator that tricks the pump to deliver more gas, and slowly returns it to normal as the motor gets warmed up.

Obviously this is the condensed version. You need the tii manual http://2002tii.org/kb/tag/manual and I strongly suggest getting hold of a wide band air/fuel meter.

Note: above link has a "click here" to download a pdf file of the manual.

I would get the basics in shape, then tackle the tii injection system after

[pilotnbr1]

Thanks for the responses! I am going to go through it and get everything back to stock with manual tolerances. Today I am going to replace all the hoses that have anything to do with the vacuum side of things. I can see where the vacuum hose going to the brake booster is suspiciously wrapped with tape.

[jp02ti]

It sounds to me like the timing is off and you're only getting it to run when the advance is kicked in.

Where in Atlanta are you? There are a few of us around the city, i'm up close to the MOG but there are others itp.

JBird was planning a get together next weekend, maybe you'll be sorted enough to meet up with us!

Jon Poole

[pilotnbr1]

Hey Jon thanks for the response! Unfortunately I will be out of town next weekend but look forward to meeting local 2002 people. I am in Smyrna just outside the perimeter.

As far as the car goes I am still sorting it out... It has had some modifications done such as a K&N air filter and a MARK 10 C ignition system which I know nothing about. Should I go back to stock with all of it? I do have the original air box in the trunk of the car and would be willing to go back to a stock ignition setup if the Mark 10 system is going to be a headache.

Question for you guys- How do you disable the fuel injection pump to perform a compression test? I pulled the number 12 8amp fuse which the legend on the sticker says is the fuel pump but then the starter would not engage...

[ray_]

K&N sucks. Please put the correct airbox back on.

There are wiring schematics on the tiiregister site. The fuel pump fuse is not on the starter circuit.

GL,

Ray

Hey Jon thanks for the response! Unfortunately I will be out of town next weekend but look forward to meeting local 2002 people. I am in Smyrna just outside the perimeter.

As far as the car goes I am still sorting it out... It has had some modifications done such as a K&N air filter and a MARK 10 C ignition system which I know nothing about. Should I go back to stock with all of it? I do have the original air box in the trunk of the car and would be willing to go back to a stock ignition setup if the Mark 10 system is going to be a headache.

Question for you guys- How do you disable the fuel injection pump to perform a compression test? I pulled the number 12 8amp fuse which the legend on the sticker says is the fuel pump but then the starter would not engage...

[pilotnbr1]

UPDATE: I haven't had much time to work on the car but was able to change plugs and plug wires. I went through all of the fuel hoses and discovered a blockage to the cold start fuel jet. I also replaced the brake booster vacuum line. This car has been completely desmogged with all but the brake booster vacuum line capped. So there is no vacuum line to the distributer. It is only mechanical advance, as I understand the vacuum line on a stock distributer is a deceleration retard type..

The car now starts fairly normally and idles at about 1000 rpm but it is a rough idle. I need to time it and check valve clearances.

My big concern right now is the fuel leak. I cannot find the source. Fuel is gathering on the drivers side of the transmission just below the starter. It only begins to gather after the car has been running. With the engine off and the fuel pump running there is no leak... I've checked the new fuel return line, lines from the KF pump to the injectors, and injectors themeselves... Its hard to see under/in the intake manifold..Ive added a picture of the area under the starter motor. ANY ideas??

I also have a mystery black pvc line coming out of the firewall next to the stainless braided fuel return line. The mystery line does not attach to anything in the engine compartment. Picture enclosed of that as well for anyone with some ideas.

[jgerock]

I would first try to eliminate that fuel leak before driving the car again. This is a safety issue.

The smaller diameter line at the firewall (sorry - almost a poor choice of words in this case) is the vapor recovery line from the fuel tank that connects to the small tube on the tii air cleaner assembly. If your stock air cleaner is not installed, the fuel vapors from the tank will not be vacuumed back into the engine.

Here is the 74tii air cleaner assembly. Not shown in this diagram are the breather hose stub and the vapor recovery stub.

This is a '72/73 air cleaner assembly

Are you sure that the braided hose isn't leaking? That hose connects to a fitting on the back of the injection pump. The fitting regulates the amount of fuel that passes thru the pump. Excessive fuel that gets past the fitting goes back into the tank.

** The sealing ring (o-ring) on this fitting is very difficult to find **.

If you remove the fitting, I certainly hope it doesn't look like this inside.

Be very careful if you decide to remove the internal pieces for cleaning. The circlip is very tiny and will get lost once out of the groove.

[pilotnbr1]

Thanks for the response and explaining what the mystery hose was! I think I am just going to replace the braided fuel line altogether. Then I will know that it isnt the cause of the leak and it will make the engine compartment look more stock.

To get to the bottom of the leak I pulled 3 of the 4 intake manifold "u" pipes off. I didn't discover the leak but am going to pull the fuel injectors and give them a good cleaning while I have the intake apart. Anyone use Chem-Dip on tii injectors?

I got a look at the stems and tops of the intake valves and they are filthy. Solid black crud completely covering the top of the valves.... Picture enclosed of one of them..

[jgerock]

Your valves don't look too bad, especially for an old tii that most likely didn't have proper fuel system maintenance.

I purchased an ultrasonic jewelry cleaner and some solution for cleaning injectors and all the little screens. Works pretty good.

I would soak them before trying to take them apart for a thorough cleaning. Some injectors I have tried taking apart have broken from old age, corrosion and many heat cycles. Make sure to purchase (4) copper washers that go under the injectors for proper sealing.

Have you cleaned your throttle body yet? Now is the time since you are removing the injectors.

Here is what I started out with.

[lilmo]

I wouldn't even consider dumping the injection. You already bit the bullet for a pump rebuild. If you wanted a carbed car you would have bought one, right? And anyway, the KFish should be good if you had it rebuilt. Did you send your injectors and warm up regulator to fairchild with the pump? If so, all should be fine. Double check KFish/crank alignment. Get the airbox back in place, all fuel & vacuum lines sorted, sync pump and TB per tii tuning guide & video, check warm up regulator setup, then do a step by step tune of the ignition. Now drive it to lunch, because all that took less than 2 hours. Just saw a posting here for the special tii tools you'll need.

You'll still need to find a shop with an exhaust gas analyzer to fine tune the mixture, but it won't take long if all else is set up correctly.

Then drive it. Tiis hate to sit.

Good luck!

[pilotnbr1]

Thanks all to your responses! You are correct lilmo that I bought a tii to have a tii and I am already invested in the injection system. I became even more invested in the fuel injection system when I ordered 4 new fuel injection lines for each cylinder to the tune of $125. The old ones seemed brittle and I figured this would be eliminating one more source of the fuel leak.

Only the pump was sent to Fairchild. The injectors sat unused for several years and most likely need a good cleaning and possible rebuild as the fuel became varnish. While I have them out I'll also clean up the throttle body and ultimately put the original air canister back on. As everyone has suggested and when I have time, I am going to go through the process of checking ignition/pump timing, pump linkages, and valve clearances. I have already seen significant engine improvement so far and believe that I can accomplish even more before taking the car to a pro.

Thursday I hope to be able to do some work to the car and will have more updates! Thanks again to all responders!!

[pilotnbr1]

UPDATE: I got the injectors out and they do look a little dirty (pic below). Going to soak them in Chem-dip and find a local place to test them. The good news is when I went to remove the fuel injection hoses from the injectors, cylinders 2 and 3 nuts holding the hoses on were not even finger tight. This explains my fuel leak and engine roughness because it wasnt getting gas.

While I have it all apart I am going to clean the throttle body as well (pic below).

On a side note one of the plastic linkages to the KF pump is cracked and needs to be replaced as well...

[jgerock]

Keep at it! Cleaning stuff is fun.

Purple Power cleaner is tough on grime

Before soaking

After just one soaking. The copper washers even cleaned up. I still have more cleaning to do.

This throttle body is too far gone.