tii Warm up valve - help needed please

[classicman]

Hi Guys

After warming up, the cone on the top of my warm up valve only extends by about 7.5-8mm. All the references I have come across state that it should lift to 10mm. Is this adjustable or do I have to just replace the unit? The car hasn't run for 10 years, so I was hoping that it was just stuck and would work loose.

The problem is that I can't set her up to run properly with it like this. The idle is OK and the CO mixture is correct at just over 2% at idle. I can't get her to rev up nicely though and she breaks down at about 3,500rpm. The CO is a bit lean at this point and she backfires slightly on the overrun.

Any advice will be greatly appreciated. Thanks in advance

[bnam]

I have a similar situation wrt to the warm up regulator.

When your regulator is cold is the piston that extends somewhat below the rim of the regulator?

In my case it is about 2.5mm below and extends about 7mm above for about 9-10mm of total travel.

When your car is fully warm is the cone fully lifted off the eccentric arm below the cone? If it is, then your warm running problem is probably not due to the warm up regulator. Once the cone has lifted off the arm and the screw on the other end of eccentric has hit regulator body -- there is no fuel enrichment happening.

So your problem of not revving above 3500 could be caused by something else.

BTW, have you set that "verboten" screw gap at 2.6mm as per the manual? If it is more than 2.6, then the enrichment happens for a longer time and if it is less it happens for a less.

The regulator is adjustable. I intend to try adjusting it this weekend and will take some pics. At 68F the regulator piston is supposed to be flush with the threaded rim. If it is below then the regulator takes longer to close. There is a 3mm allen screw that needs to be loosened and then the piston that moves can be rotated around the threaded shaft and raised or lowered.

My car runs well when warm. It idles well when cold. But in between - when the temp gauge needle is at the top of the blue (cold section) or the bottom of the white (warm section), the regulator is still open and letting air in and causing my car to idle too high -- at 2500rpm. Then when it warms up a little bit more, the regulator closes and idle drops down to 900rpm after that and runs well.

Byas

Hi Guys

After warming up, the cone on the top of my warm up valve only extends by about 7.5-8mm. All the references I have come across state that it should lift to 10mm. Is this adjustable or do I have to just replace the unit? The car hasn't run for 10 years, so I was hoping that it was just stuck and would work loose.

The problem is that I can't set her up to run properly with it like this. The idle is OK and the CO mixture is correct at just over 2% at idle. I can't get her to rev up nicely though and she breaks down at about 3,500rpm. The CO is a bit lean at this point and she backfires slightly on the overrun.

Any advice will be greatly appreciated. Thanks in advance

[Richard]

Take the warm up regulator off and clean it??? They are infamous for sticking...

[ray_]

Check your ignition system.

GL,

Ray

[pilotnbr1]

Even though you may have a gap between the warm up transmitter washer and the lever arm of the regulator, when it is warm you may be running lean. The lean condition is caused by an incomplete shutoff of the auxilliary air. My understanding is that you can adjust the fuel relationship somewhat by adjusting the position of the regulating lever and grub screw gap however aux air is only shutoff by the complete extension of the warm up transmitter rod.

The Macartney manual has a method of adjusting the warm up transmitter which eliminates some of the variables of our old worn cars.

[BillWilliams]

If you think you are getting some air through the warm up regulator, spray some carb cleaner or unlit propane at the slits in the warm-up regulator when your car is running and after it comes off of the warm-up cycle.

If leaking you will hear the motor rev a bit.

If no rev, check elsewhere, Remember "90% of your fuel problems are in your ignition"

[bnam]

I too think that running problem above 3500 is not related to the regulator.

Anyhoo... here're a couple of pics I took today on adjusting the regulator. These are on my spare which sat about 1 to 1.5mm below the threaded rim at 68F.

I heated it up in some water

The allen screw is visible. There are 3 ramps/slots along the edge of this piston. Air is let in thru these slots. As the piston rises these slots get smaller (as they are ramped) and let in less air. Once the piston rises about 8 or 9 mm the slots are closed. So, if the piston sits low, then it lets in air for longer.

Loosen the allen screw by half a turn. Now the piston will rotate around the central threaded shaft. I turned it out little over a turn -- each turn is 1mm.

Almost flush now. Actually when I measured inside the regulator it was closer to 71. At 68 it was completely flush.

Byas

[classicman]

Thanks guys, this has been quite helpful. I will try the ajustment over the weekend and see if it makes a difference. I haven't checked to see if the cone is flush or recessed when cold.

With regards to the ignition, the points, condensor, plugs, plug leads and coil are new. I went back to points as my pertronix ignitor is faulty. I'm still running the 40,000 Flame Thrower coil though and have disconnected the external ballast resistor as I have the required 3ohms across the coil. Could this be the problem?

[c.d.iesel]

........all that, above, plus

(i'm blue in the face)

-correct valve adjustment

--good even compression readings

---FUEL PRESSURE TEST READINGS

----igniton timing set at 2500 rpm

-----NEW gas in the tank

------clean , not gas deluted motor oil

everyone will contribute to your running problems

[classicman]

OK, so I've checked my cone and it is virtually flush when cold, so I guess it's sticking more than out of adjustment. Is relatively simple to strip, clean and reassemble this unit? The BMW manual says not to try.

@c.d.iesel - lol, I haven't been ignoring your advice. The motor is newly built, rebored with NEW 89.5mm pistons and rings, so I'm pretty sure the compression is good and equal (raised to 10.0:1 from the std Euro 9.5:1). The car is newly restored, so all the fuel lines, filter etc are new and the gas tank was cleaned and new fuel added to a dry tank. I haven't checked the fuel presssure, but I checked the return flow to the gastank, and 1L of gas is pumped back in 30sec which falls into the 0.8-1L that I have read in the manual.

The timing was set statically - the points just about to open with piston #1 at TDC on the firing stroke. I don't have an adjustable timing light, so any advice on how to set the timing at 2,500rpm will be appreciated.

[bnam]

Before you take apart the regulator -- take the regulator off and check to see if the coolant passages are clear. Put the regulator in boiling water and see if it does rise to 10mm.

But, before you do that -- so some more checks:

1. When the engine is warm does the eccentric screw bottom out? If it does not, it would indicate there is continuing fuel enrichment. Loosen the nut over the cone on the regulator to make sure the screw bottoms out when hot. This takes the fuel enrichment out. Do you still have the issue?

2. Again, when engine is warm, clamp off air hose that connects the warmup regulator to the bottom of the throttle body. This takes the warm up circuit out of play. Any change?

I think the regulator can be taken apart, but start with the above.

Byas

[BillWilliams]

he needs to get his timing right before anything.

Do a site search on timing a tii, hundreds of threads

[c.d.iesel]

don't over think it - 'advance' timing not needed$$$

just use basic timing light without

advance function - hold rpm's

steady at 2500 and rotate the distrib untill

you align the "BALL" mark in the inspection

hole as illustrated below. The timing being off

can cause uneven performance. Once you set it at 2,500 rpm,

never touch the timing again - move on to injection linkage,

warm-up regulator, injector nozzle pressure testing with spary pattern

and leak testing - injectors must be in good condition........... cont.

[classicman]

It's amazing how easy it actually is when you know what you are doing!!

Thank you all for your advice, and yes it was the ignition and not the pump settings. I replaced the points as the set that I had were faulty, set the dwell angle to about 60deg, and the timing as advised at 2,500 rpm. Hey presto, she is running quite beautifully. There is a bit of pre-ignition (run on) when I switch her off though, so I might need to back off on the timing a little.

I still need to check the CO readings, but this should be a cinch now. I had also sprayed quite a bit of penetrating oil on the cone of the warm up valve, and it is now opening the full 10mm. Luckily I didn't even need to take it off.

THANKS AGAIN GUYS! Tomorrow I road test.

[ray_]

Whatcha idling at? I think tii's are spec'ed at 1100? Too high an idle may contribute to run-on.

And bad gas. And timing....

Cheers,

Ray