So, my tii is being frustrating... Is it worth it?

[irdave]

Wow.

 

Thank you all so much.  That's a little bit overwhelming.

 

And knowing that there is someone, at least in Colorado, that knows something about this beast is reassuring.  Thanks Paul.

 

Maybe I'll step back for the next week, read a little bit about the fuel injection, get some linkages coming, and start next week fresh.

 

Thank you all.  Really, I appreciate it.

[chargin]

18 hours ago, AustrianVespaGuy said:

Just one sec while I finish zipping up my flamesuit. . . there! Ok ready!  So, plenty of differing opinions out there I'm sure, but if I had a tii that was giving me K-fischer troubles, I'd remove most of it except for the intake, change it over to EFI, and then sell the rest of the Kuglefischer parts to other tii-purists in need to offset the conversion.  Not something I'd recommend to someone 'looking for' a tii, but since you've already got it and are considering your options, figured I'd chime in.  Not that there's anything wrong with carbs either mind, but helps keep that second 'i' in the tii, ya know?

 

Yea, like bringing home a Victoria Secrets Angel to have her do your dishes

 

All joking aside, if the Tii is not your cup of tea I would sell it and by a Twin Carb 02 before I'd retro grade a Tii. Just my opinion and only worth what you paid......$0.00

 

I was at a local tuner and did see a Tii converted to carbs, as well as a full Megasquirt fresh build at SoCal Vintage and that car actually won an award

 

 

[jimk]

FAQer cpolyak knows where to have it adjusted for high elev.

[golftii]

16 hours ago, mvliotta said:

 

The first couple of steps, which were critical for me, were to 1) replace all the ignition components and 2) eliminate vacuum leaks. Then proceeded to timing, injector cleaning, and tuning. A wideband O2 meter (AFR sensor) was great to have for the latter steps. 

 

 

 

 

 

++ on the ignition and air leak comments in addition to the usual suspects of linkage and throttle adj. Combination of pertronix ignitor and replacing black induction tubes with the steel/silicone set from Top End Performance have my 72 running and idling best ever (of course, keep the OEM plastic tubes for next owner or your future concourse shows )

[saaron]

I have nothing to add to the (much more informed) opinions than mine, above, other than keep going at it.  I'm not big on working on it, myself, but I sponged up all the info out there, so at least I know how it works.  I have adjusted some things in the tuna can to make it run better, so it can be done by dummies, or at least dummies that read a lot, and ask questions of experts.  

 

I would agree that starting with the MacCartney book might be a good idea, because his basic approach is to adjust/work with what you have, vs. "set everything like the factory says".  His view is the cars are old, and nothing is close to factory spec anymore, so don't be obsessed by that.  

 

I do know enough to know that if your car was set up to work at lower elevations, the overall fuel mixture is probably incorrect, which is probably going to cause problems in warm up, idle, and warmed up running.  It is probably running too rich, I would guess.  

 

One thing for sure is that the ignition timing is a big deal.  I had my distributor rebuilt by Advanced Distributors in Minnesota, and learned how to set the timing myself.  That did make the car run a little smoother, and it has better throttle response now.  Also spark plugs matter, and the gap.  So research that so you have that little detail correct.  

 

I agree with others' view - once it is working OK, you never need to mess with it.  I've had mine since '87, and while I have improved how it runs, it basically has always run decent, and nothing in the injection has ever failed.

 

Scott

[inkatouring]

I've had 4 tii's over the years and could never get them running right myself -- myself.  And I do almost all work on my cars, including building multiple motors.  Once properly tuned by someone who could do it, they're the best.  Period.

[Einspritz]

I was perusing the discussions and came across your post, which I might be able to lend a few ideas.

 

MarkMac has the right progression, but I would like to add to that, as you didn't mention much of the current state for us to go on.

 

You can replace the linkages, but that won't do much if the balls are worn; otherwise you need to seek out new balls with threaded fitments, press out or drill out the old and in with the new. You can cheat for a short time by slicing a thin piece of silicone vacuum line and putting it into the cup to take up the errant space, but not too much as the linkage may pop off.

 

If the linkages are worn it is probable that all the other bushings in the bellcrank linkages from the pedal to the intermediate shaft are worn too, and it would be wise to replace those to avoid any "racking" of the arms.

 

Check the plastic bushing cup for the bottom of the intermediate shaft, as well as the ball there. Axial movement there makes it hard to keep a setting from changing.

 

On high mileage cars, the shaft for the cam in the throttle body does wear either the shaft and / or the aluminum body. The cheap repair for the shaft is to fill it with JB Weld and file to fit. I recommend and rebuild the corresponding surfaces with a bronze bushing to avoid further wear. I use Krytox grease to avoid any future wear.

 

Check the rubber boot on the bottom of the throttle body as these tend to be overlooked, and crack and leak, affecting the idle with false air. I don't know if they are available, and if not, you can use "liquid electrical tape" and do a nice job of painting the outside to seal it up. More can be done on rebuilding the throttle body, but I won't go into it here.

 

IIRC you mentioned that it is a '72. do you have the plastic runners? If so make sure that there are no air leaks at the o-rings, they tend to flatten over time. I do not recommend just tightening the clamps, particularly on old tubes as the ears tend to break. If you are replacing with new ones be sure to either heat them in boiling water or with a heat gun, but not so much as to melt the ears. Remember: these are sealed by the o-rings, not particularly the clamps. Resist going to your local hardware store for replacement o-rings..they are not the same.

 

You didn't mention what you did in your "adjustments", and hope that you didn't "turn the screw" on the pump; particularly if you didn't measure and record what you did.

 

I have experience tuning these systems for altitude; I used to drive regularly from sea level to almost 8000 feet and lived at 7000 feet for many Summers. The thing to understand is that the air at, say 6500' is about 80% as dense as at sea level. So yes, you will at least have to lean out the idle. I wouldn't recommend adjusting the fuel curve at this juncture just to chase an idle issue. The car will idle at your altitude, but yes, be rich. In addition, see below about the gas as a cumulative effect on your tune.

 

But the elephant in the room, and the thing that all the books and articles NEVER address is the gasoline. This is not 1972. The Kugelfischer systems are tuned run via fuel density. And 100 Octane. Gas in California and I assume in Colorado is a blend of ethanol (<20%) and gas. Moreover, there is at least in California a Winter and Summer formula. As such, my Tii and Turbo need to be tuned twice a year when the gas changes for the optimal tuning.. I notice a 2mpg loss in the Winter formula. Or use 100% gas or race gas and not mess with that. Ideally, the pump should be calibrated for the gas that you use, and not the OE spec.

 

My point is that all those books, articles, and manuals are a starting point to a good Tii tune. So, begin there; check for vacuum leaks, make sure that the distributor curve is correct and set properly, the coil is good, you have proper fuel pressure and flow (check the amperage draw on your fuel pump) , the cold start system is working, all the other stuff the manuals tell you to check. You need to establish a baseline. Then and only then can you get to the root of your problem.

 

One last comment about changing to carburetors; yeah, they can be fun, but you will never be able to drive 80 mph @ 4000 rpm for hours on end and get 30-32 mpg....with more power on tap...In fact, when I restored my 2002, I ditched the carburetor engine with all its non-SMOG compliant headers and Weber, and installed a Tii motor with 9.6:1 CR and  the "Euro" cam in the pump. More power, better gas mileage, no SMOG and passed emissions with flying colors. A faux Tii.

 

" Once properly tuned by someone who could do it, they're the best.  Period. "

 

Yup.

 

HTH

 

Ted

 

 

 

 

[irdave]

Again, thank you all for the support.  A little time away, spending a few days with friends, has been helpful; as have been all of your suggestions.

 

A little background- the car is a '72 tii with the plastic intakes with 242,000 miles.  It was abandoned for 30 years.  I replaced all the fuel lines and installed a new pump, cleaned all screens and replaced any filters that couldn't be cleaned, disassembled the injectors as much as easily possible, and the car ran on all 4 cylinders and was somewhat driveable.

 

I spent some time, as suggested, studying the injection system and reading through the blue service manual and other sources, understanding the progression of adjustments- and the reasons for such...

 

I found a place to test the injectors- they're all opening at about 350 psi and not sealing well.  The WUR is adjusted very wrong, which is interesting- at about 68 degrees F, the 'cap' is recessed 7 or 8 mm down in the WUR...  I have a spare that is adjusted the same way, but moves the required 10mm on warm up, so I'll pull the current one and test and adjust or replace as necessary.  Both of these, obviously, will contribute the running very rich issue.  I did find a thread about shimming the injectors to increase the opening pressures.  I'm trying this and will retest.

 

I found a place in town that can spin my distributor.  It will be dropped off on Monday, along with the spare, to see how off they are.  With as much as everyone talks about the timing been the main fuel injection issue, I'm thinking about a 123 distributor to take that out of the equation. The car has a Motorola electronic ignition- from what I do not know.

 

Is it preferred to try to replace all of the stock throttle linkage with NOS parts or is it thought ok to build a new kit from parts through McMaster Carr?

 

The car runs non-ethanol 91 as it's available at the pump here in town.

 

The TEP steel intakes.  Are the plastic ones that bad?  I'm really looking for something that runs well and is moderately reliable- I don't need it to be stock...  So if the plastic ones should just be replaced-

 

Again, thank you all.

[ray_]

Excellent progress!

 

If you've ensured the plastic intake tubes are leak-free, no need to replace.

 

Have you read all the tii-related articles here?

 

https://www.bmw2002faq.com/articles.html/technical-articles/engine-and-drivetrain/

 

Cheers,

[adawil2002]

I have an extra set of '73-'74 aluminum intake runners and plenum I'll sell for less than the $325 TEP runners.

 

Jack Fahuna at JFPro BMW in Van Nuys CA, will make you a new set of linkage rods, you have to call him.

[Einspritz]

I'll comment on the intake runner system first. I don't know what TEP steel runners are, but each of the plastic and aluminum runners are very specific in their length, shape and volume; they are slightly different in dimensions, but the same in how they work.

 

These systems, intake AND exhaust work in concert to create an engine that is much more efficient than your standard M10.The intake runners and plenum are designed such that their shape and volume creates a pulse tuning effect both in the volume of air moving and sonically. What this meas is that whereas say, dual webers can only provide up to 14.4psi (or ambient air pressure) to the engine, the Tii is tuned such that it produces 15.5 psi. at the resonance RPM of 4500 RPM, which is where peak torque is for most of these engines.

 

The Tii exhaust manifold is tuned too. It is a Tri-Y unit that has different lengths (unlike an aftermarket  Tri-Y or 4 into 1 header) that in essence spreads out the torque so that it is not as "peaky" as a race engine.

 

My point being that unless you measure and do the calculations on any modification either intake (TEP) and exhaust (aftermarket header) you are probably going to reduce your efficiency and output from the OE. I kept the plastic runners on the '72 because they are OE and I think they tipify the earlier Tii engines. I think too many people dislike them because they don't understand them and are ham-fisted when it comes to installation.

 

Injectors: I don't know your level of expertise, but rebuilding  the injectors is really not as simple as taking them apart, shimming them and checking the cracking pressure. You say they leak too. Problem. They need to be rebuilt such that not only the cracking pressure is correct, but the spray pattern, the volume of fuel delivery at a certain pressure and  no leaking. Of course, with a non flammable fluid that is the same density as your 91 octane pump gas. AND they need to be exactly the same!

 

Electronic ignition: never heard of a Motorola system, but that should be checked (or removed) , as well as the wiring to / from the coil, the resistor circuit if still enabled, and the resistance of those wires...a lot of corrosion can happen in 45 years. Ditto for the spark plug wires; did you check the insulators for cracking / arcing with the head, and the resistance of the wires themselves?

 

Linkages: You can order them from Jack (support the vendors who help you) , or other vendors, but see my earlier post regarding this.

 

Warm Up: I don't recall off hand, but there is a temperature range e.g. start and end and a dimension for the regulator.....I would have to dig into my references for that, but at this juncture, just make sure that the travel is sufficient to meet spec.

 

Now, the perspective that this project needs to have is that the engine and car is 45 years old and has 240,000 miles. (My faux has over 200K or is it 300K on this engine and over 400K or is it 500K on the car, so i am not prejudiced). So there is merit in thinking that there is sufficient amount of wear both in the valve seating and the rings being able to seal as well. The injection pump will have wear and probably rust on the cam as well. Since the car sat for decades, all sorts of gremlins get in the way. So, you are trying to chase ("just") a perceivable idle  problem at altitude when you have all these other factors contributing against you.

 

Even so, you should still be able to get it running.

 

Best

 

 

[golftii]

3 hours ago, ray_ said:

Excellent progress!

 

If you've ensured the plastic intake tubes are leak-free, no need to replace.

 

 

Agree, was not implying anything wrong with plastic runners, just that it’s critical to make sure they are not cracked/leaking, which is not uncommon. In addition to the tabs on ends cracking off and the o-rings (AKA string rings) not sealing well, I’ve also had tubes crack longitudinally along What looks like the mold separation line. So if you find you already have broken/damaged plastic you have a decision to be made whether to stick with OEM or switch to TEP steel or post-72 alum plenum & runners as Andrew is offering.

[Einspritz]

Yes. Unfortunately the "new" plastic runners are not the same material as the OE runners. It is a stiffer plastic, and in my view, not as good. IIRC the OE tubes were nylon. Yup they can crack, so I always keep a roll of silicone stretchy tape in the trunk in order to wrap the tubes as a "bush fix"......and you thought it was for the other type of "plumbing".

 

That said, a late model intake is probably less than a set of plastic tubes these days........but not OE if that is your thing.

 

It is too bad that BMW only "Talks the Talk" as far as reproduction parts are concerned for older cars. I see this on the E30 M3 and turbos as well. don't even get me started on things like oil coolers and wiring harnesses. I'll source or make my own now, thank you. Good thing though, that I started collecting parts 30 years ago, but could never buy enough.

[deschodt]

I'd keep the Tii as a Tii.... It's where the money is and they are next on the totem pole of collectibles that will be $$$ someday soon. 

 

On the other hand a base 2002 like mine, upgraded to EFI with 318 stuff and a DTA computer, has been rock solid reliable for 10 years with zero tuning... In other words I'd try to fix your Tii, but if I owned a non-Tii I would not think twice about going EFI. It's been amazing in terms of power, start, reliability and total lack of maintenance....

[jgerock]

Worth keeping the tii a tii?  Yes.