Jump to content
  • When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

New '72 Tii engine running problems


Recommended Posts

Hi, All -

My car's resto is mostly finished.  I put in the seats and the center console.  I am down to making it run well.  After diagnosing a bad temp/time switch (a new part!), I put bought and put in a spare.  Now the car starts immediately, since the 5th squirts for 1-2 seconds.  After the two seconds is over, it runs poorly.  I have to massage the throttle to keep it running.  After a minute or two, it runs by itself with the throttle stop in the tuna can cranked up a bit, though it "hunts".  It should run all by itself, right? ? BTW, I have a reworked Kugelfischer pump, reworked injectors, and a reworked distributor.  

 

I have been messing with the throttle stop and the CO screw in hopes of better behavior with some luck.  Before I melted my timing light lead on the exhaust manifold, I tried retarding the timing 4-5 degrees.  Slightly better, though when I drive down the driveway and back, it feels doggy.  I pulled a plug - slightly on the rich side, probably ok for now.  Maybe the engine is just new.   I would be interested in anyone's thoughts, thanks!

DSC_1645[1].JPG

  • Like 1
Link to comment
Share on other sites

Cold start valve is like a primer pump on a carb.

Warm up regulator is like the choke on a carb.  Check it's settings.

 

It takes 30 seconds for the flame to stabilize in any engine, and needs quite a bit of choke.  After that the enrichment tapers off quickly. 

  • Like 1

A radiator shop is a good place to take a leak.

 

I have no idea what I'm doing but I know I'm really good at it.

Link to comment
Share on other sites

I always encourage people to put their location in their profile. There are so many knowledgeable guys in many parts of the country (but especially CA, OR, and WA) who could help you in person way faster than working through a few pages of a thread. 

 

With that said, on my Tii, if it hunts, it has a vacuum leak, causing a lean condition. Check the little hose coming out the right side of the throttle body, ensure you have a cap on the bottom of the throttle body, and check your long hose coming from the warm up regulator in to the upper intake. Can also leak vacuum from the hose to the booster and the booster itself (usually only when brakes are pressed).

  • Like 2

'74 2002Tii Sienabraun: Henrik

'67 Ford Galaxie 500: Grandpa

Link to comment
Share on other sites

3 hours ago, Stein-man said:

After a minute or two, it runs by itself with the throttle stop in the tuna can cranked up a bit, though it "hunts".  It should run all by itself, right?

 

Do as @xavier296says first.  Then start your engine and wait for the WUR to extend completely.  It could be leaking and allowing uncontrolled air to enter the system.  It (the piston) should also extend to free up the enrichment lever on the pump.  You can test the seal of the WUR by clamping the air hose on the back of the unit with long needle-nose pliers.  If the engine changes RPM then the WUR is allowing air into the system.  If no change, you can continue with your tune.

 

Turn off the engine.  I would back-off the air screw  in the tuna can completely as per the injection manual, and turn it back in 1 1/2 turns to allow some air into the throttle body.  Restart the engine.  It will likely hunt.  You then back off the air screw 1/16 turn and listen for a change in the frequency of hunting.  Rev and hold the engine at 3000 rpms and listen for a change in rpm, as well.  Continue to back off the air screw until the hunting disappears at idle and at 3000 rpms .  You will likely have to increase the idle with the idle screw on the outside of the tuna can.

 

Hope that helps.

 

Car looks great!

 

 

Edited by PaulTWinterton
  • Like 1

73 Inka Tii #2762958

Link to comment
Share on other sites

To All -

I am in Boulder, Colorado.

 

Jim K -

Thanks for your words of wisdom.  I have avoided the whole topic, since I sent it out for full rebuild.  As things go, the 2-3mm gap in the preheater in the cold position was zero.   It's still hunting and doesn't want to idle.  

 

Xavier -

Thank you for the good ideas.  A vacuum leak makes some sense around here, since coughing back through the throttle is part of current behavior.  The little hose coming off the throttle body tees into the larger hose that vents the valve cover and goes to the air cleaner.  It should run fine with no air cleaner, right? 

The hose from the warm up regulator to the intake plenum is new, and firmly cinched down.  

 

Paul -

I have clamped the hose from the WUR to the intake plenum when the engine is hot, and nothing changed.  I also have messed unendingly with the CO screw and the throttle stop screws.  The throttle stop screw needs to be screwed way in just to keep the engine running.  Your injectors are working great, though!

 

- Rob

Link to comment
Share on other sites

Rob - nice tii! I am in Arvada, and my daughter is in Boulder at CU. If you get to a point where you need somebody to look at it, the one guy I have found in the area who knows tiis is Mark Hutto. He rebuilt my '74tii head and lower end a couple years ago. He knows what he is doing. 

 

Good luck!

 

Andy74tii

  • Like 1

FAQ Member #126

Link to comment
Share on other sites

You might need to get off the beaten path a bit from factory settings due to your elevation. Finding someone local who’s done it before would be a great shortcut but I would work through the factory set up procedure to familiarize yourself with everything and go from there. An AFR gauge is invaluable for tuning but you should be able to get a smooth idle easily without one. 

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

Hi, Andy -

Thank you for the kind words.  Mark H. and I have spoken a few times during the past 18 months, during which I put my car back together.  He's reluctant to do a house call, but maybe it'll happen this time.  Before I saw your post, I called him and left a message.  

 

Hi, Mike -

I am on the path to finding someone local that can be my Kugelfischer whisperer.  I have read and pretty much memorized the factory procedure and one from Jaymic.  They both say pretty much the same thing.  I thought a WUR would do it, but it didn't make anything better.  Hmmm.

 

- Rob

Link to comment
Share on other sites

Are the throttle body and injection pump a 'pair' since new?  I think for most of our cars the answer is probably not or don't know.

If they are not a pair then the injection handbook's setup with the 4mm stop in the tuna can doesnt work, as the 4mm stop was factory-set as part of the matching of pump/mechanism/engine, i believe.

Its not a big deal, just go through the setup routine in the FI manual, but dont use the 4mm stop, position the D cam part-way over or completely covering the 4mm hole and then finalise the setup per the book. This alters the sync of throttle body to the injection pump, effectively putting the injection pump 'higher up' the fuel delivery curve for a given throttle opening (means richer). Remember, the tii system is completely 'dumb'...its beautiful mechanically optimised combination of parts, but its got only throttle position and engine speed as inputs...and that throttle position input assumes everything is mechanically as it left the factory.  The actual throttle opening or manifold pressure it doesnt 'know'...it 'assumes' these and fuels accordingly. You can alter that assumption by moving the D cam over the 4mm hole during setup.

 

 

  • Like 2

'59 Morris Minor, '67 Triumph TR4A, '68 Silver Shadow, '72 2002tii, '73 Jaguar E-Type,

'73 2002tii w/Alpina mods , '74 2002turbo, '85 Alfa Spider, '03 Lotus Elise

Link to comment
Share on other sites

Have you bought an innova 5568 timing light yet? This site recommends it over and over, and it does work well. Even lean, it shouldn't cough through the intake, so I would be worried about timing and dwell being  correct, both which can be set using that timing light.

 

I went to the school of mines, and had boulder friends, so am very familiar with your area. I agree with the statement about finding other high elevation friends who have good running Tiis since the lower oxygen will definitely change your tune. 

  • Like 2

'74 2002Tii Sienabraun: Henrik

'67 Ford Galaxie 500: Grandpa

Link to comment
Share on other sites

D -

I get what you are talking about with moving the eccentric to mod the AFR of the engine.  I will try this today.  Thanks for the tip!

 

Xavier -

A day or so ago, I melted my #1 plug pickup lead on my timing light.  I just ordered an Innova 5568, they look great.  

 

All - 

I have spoken with a local wizard.  Since everything else is brand new, we decided that I should focus on the throttle body, which reflects what D says.  Also wizard recommends capping the tap that ties into the valve cover vent pipe.  I'll be working today, it seems!

 

- Rob

Link to comment
Share on other sites

10 hours ago, Stein-man said:

D -

I get what you are talking about with moving the eccentric to mod the AFR of the engine.  I will try this today.  Thanks for the tip!

 

Xavier -

A day or so ago, I melted my #1 plug pickup lead on my timing light.  I just ordered an Innova 5568, they look great.  

 

All - 

I have spoken with a local wizard.  Since everything else is brand new, we decided that I should focus on the throttle body, which reflects what D says.  Also wizard recommends capping the tap that ties into the valve cover vent pipe.  I'll be working today, it seems!

 

- Rob

Brand new parts doesn’t necessarily mean they are good. Ask any mechanic about this.

Jim Gerock

 

Riviera 69 2002 built 5/30/69 "Oscar"

Link to comment
Share on other sites

Are you sure your intake runners o-rings are seated correctly? It’s super easy to roll an o-ring out of position when installing the intake runners. 
 

ask me how I know.....

Edited by gwb72tii

72 2002tii

1988 535is  “Maeve”

Link to comment
Share on other sites

Having tuned my tii at both sea level and at 7800 feet, I can second the need for a WBO2 or AFM sensor.  Everything else is really guesswork. Also, I don’t believe the D cam in the tuna can affects fuel ratio in a linear manner, it’s not a matter of simply rotating it until the mix is sufficiently lean or rich.  As Preyupy explained it to me at a show once, those brilliant German engineers took advantage of Hemholtz resonation to stuff more air into the engine at some speeds, accepting some losses at other speeds.  The fuel cone is therefore an asymmetrical cone, to provide more relative fuel at some points, less at others. Synchronizing the D cam is effectively aligning the fuel cone and throttle body relative to that Hemholtz affect.  

 

However at 5,200 feet, if your car and pump weren’t previously set for that altitude, you’ll likely need to adjust the Verboten screw, which *does* affect the fuel ratio across the board.  I’ve also heard some amount of this adjustment is also needed for modern fuels, which seems reasonable too.  My tii took over 2.5 turns to find the right mix, and now it really rips!

Edited by Solarphil
  • Like 3

1987 E28 535is -- Buttercup

1974 2002tii -- Pretty Penny

1994 E34 M5 -- Horehund

2001 E36/7 M Roadster -- Shaggy

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • BMW Neue Klasse - a birth of a Sports Sedan

    BMW Neue Klasse - a birth of a Sports Sedan

    Unveiling of the Neue Klasse Unveiled in 1961, BMW 1500 sedan was a revolutionary concept at the outset of the '60s. No tail fins or chrome fountains. Instead, what you got was understated and elegant, in a modern sense, exciting to drive as nearly any sports car, and yet still comfortable for four.   The elegant little sedan was an instant sensation. In the 1500, BMW not only found the long-term solution to its dire business straits but, more importantly, created an entirely new
    History of the BMW 2002 and the 02 Series

    History of the BMW 2002 and the 02 Series

    In 1966, BMW was practically unknown in the US unless you were a touring motorcycle enthusiast or had seen an Isetta given away on a quiz show.  BMW’s sales in the US that year were just 1253 cars.  Then BMW 1600-2 came to America’s shores, tripling US sales to 4564 the following year, boosted by favorable articles in the Buff Books. Car and Driver called it “the best $2500 sedan anywhere.”  Road & Track’s road test was equally enthusiastic.  Then, BMW took a cue from American manufacturers,
    The BMW 2002 Production Run

    The BMW 2002 Production Run

    BMW 02 series are like the original Volkswagen Beetles in one way (besides both being German classic cars)—throughout their long production, they all essentially look alike—at least to the uninitiated:  small, boxy, rear-wheel drive, two-door sedan.  Aficionados know better.   Not only were there three other body styles—none, unfortunately, exported to the US—but there were some significant visual and mechanical changes over their eleven-year production run.   I’ve extracted t

  • Upcoming Events

  • Supporting Vendors

×
×
  • Create New...