72 2002Tii running, starting issues.

[Golfcar]

Car- 1972 2002 Tii.

 

Problem- hard starting on new rebuild. 

Engine has run some but removed spark plugs to check compression.

#1 & 4 were darker but 2 & 3 hardly looked like they had run at all. 

Compression ok, 120 or so for all cyl. 

 

History- this is an original engine to make a matching numbers car. 

It was rebuilt with new pistons, ring, bearings, and head was rebuilt at reputable machine shop.  

Injectors were sent to FAQ guy to be checked. 

KF was rebuilt 5+ years ago but has had warm-up regulator rebuilt in last few weeks. 

All the KF tools were used to set the rods and controls of the warm-up regulator to specs. 

 

We had a leaking hose from KF to engine so had to stop and fix that. 

The control for cold start is one of the electronic ones from another FAQ guy. 

 

We've checked the spark, and cracked each fuel line at the KF during cranking to make sure fuel was going to the injectors. Yes on both. 

We had the timing set with a timing light when we had it running before. Got ball in sight at 2500 RPM as per the manual. 

We do have the blue books and some allied info about the KF and start up control box. 

 

Today I checked the dist to make sure it was pointing at #1. I did move it one notch over to get it dead on. I'm know that messed up the timing but feel sure I'm pretty close. At least to start. 

 

Experience- built many engines, mostly M30 and S38. Ground up restoration of a 72 E9. Long time BMW owner of an 88 M5, 72 3.0CS and 72 Tii. 

 

Today- fires, spits and sputters. Moving timing it was popping out the exhaust and the other way it did the uh,uh,uh with too much advance. 

 

I may try another coil. Spark was good at a plug held to engine but under compression it may not be enough. 

 

This engine is basically brand new with no $$$$ spared. 

It should start and run like a clock. 

 

At wits end. 

 

What say you??????? 

Thanks, 

Gary Beck 

 

@tomphot

@wegweiser

@thehackmechanic

 

 

 

 

 

 

[wegweiser]

Take it to a tii specialist. The "book" will only get you so far. The rest relies on intuition, experience, and data acquisition..... like how much gasoline squirts during a 5 second pulse of the cold start valve? Does the cold start valve weep when under 29 psi of pressure? Does the cold start valve get voltage and ground when the car is cold and key is in START position? have you tested the thermo time switch in the upper coolant manifold? 

 

"Got ball in sight at 2500 RPM as per the manual".... that just means that your ignition timing is perfect at that particular rpm. Who the hell knows what it's doing at idle? At 3800 rpm? In between? Get an adjustable timing light. Mark TDC on the crank pulley UP FRONT...and graph / map the advance curve every 500 rpm to 5000 rpm. If you're using a whiz-bang 1-2-3 unit... well.... try an analog one instead. 

 

 

Money is no substitute for expertise. Start with having the distributor rebuilt / properly curved at "Advanced Distributors" in MN. He's GOOD.  

 

 

HTH!

 

Paul

 

 

[OriginalOwner]

If you've still got points, here's the one that I learned decades ago:  The Point Gap.  I had starting problems on my '74tii and when I checked the point gap, it was nearly closed.  Re-gap'ing to spec solved the problem.

 

And I earned brownie points with a pal a few months later.  Her VW had begun the hard-start problem.  I checked the point gap:  yep, too small.  Re-gap'ed to spec and problem solved.

 

Cheers,

 

Carl

 

[dlacey]

Hey Gary,

Have you run it long enough to get it warmed up? Does the cold start injector spray ok during initial cold start?
Assuming valve timing/clearance and ignition timing are OK  then its gotta be mixture... can you reach-in with one hand to push down the enrichment lever on the back of the KF pump??  With that you can roughly richen the mixture...can you find a position where it runs better? If yes then it confirms weak mixture...then you can search for the cause.

[tomphot]

1 minute ago, dlacey said:

Hey Gary,

Have you run it long enough to get it warmed up? Does the cold start injector spray ok during initial cold start?
Assuming valve timing/clearance and ignition timing are OK  then its gotta be mixture... can you reach-in with one hand to push down the enrichment lever on the back of the KF pump??  With that you can roughly richen the mixture...can you find a position where it runs better? If yes then it confirms weak mixture...then you can search for the cause.

 

Thanks for the response.  I have bought 2 of your WUR kits - 1 for the one in the car and another for an extra I had on hand.  When we first started the engine, it got going, without too much effort, sounded rough at low rpm's but good when at higher rpms, we then worked on timing with the ball and thought we had it.

I then noticed a leak at the only hose I didn't replace going into the WUR.  Changed it out, then went through the whole Kfish adjustment manual.  mad sure all linkages were perfect from pedal to tuna can.

Went to start again and no go as you see above.

We haven't check the cold start spray volume but know that it is spraying due to the gas in the tube leading to the air filter which is not attached.  All those components worked fine before. 

[Mike G]

120 seems low for a rebuilt tii. 

[tomphot]

15 minutes ago, Mike G said:

120 seems low for a rebuilt tii. 

 

Yes , we may need to check his 30 year old gauge and attachments 

[dlacey]

1 hour ago, tomphot said:

Went to start again and no go as you see above.

We haven't check the cold start spray volume but know that it is spraying

The engine should start on this spray alone, even if KF was in-op for some reason it should still start on the cold start spray.

 

? triple check the firing order?

[tomphot]

12 minutes ago, dlacey said:

The engine should start on this spray alone, even if KF was in-op for some reason it should still start on the cold start spray.

 

? triple check the firing order?

First thing in the AM!!

[torquewrench80]

A 72 with the plastic intake runners? Make sure the o-rings for those runners are in position properly. It is not at all difficult to get them installed incorrectly. Otherwise, massive vacuum leaks will occur, and the engine may not even start.

[tomphot]

11 hours ago, torquewrench80 said:

A 72 with the plastic intake runners? Make sure the o-rings for those runners are in position properly. It is not at all difficult to get them installed incorrectly. Otherwise, massive vacuum leaks will occur, and the engine may not even start.

Thanks, I was meticulous when installing the plastic runners.  I had 6 to choose from and thought I had picked the best.  Doesn't mean there isn't a leak.  I will do a cigar test later.  I still have the Alum runners that were on another engine that I have just in case. 

[tomphot]

14 hours ago, Mike G said:

120 seems low for a rebuilt tii. 

 

Yes we thought that as well however everything hasn't even had a chance to seat in properly yet.  It's only run for about 15 minutes.

[Stevenc22]

Rig the cold start injector with a switch to power and ground and see if you can start the car by manually firing the cold start Injector.

[Golfcar]

On 9/18/2024 at 4:46 PM, wegweiser said:

Take it to a tii specialist. The "book" will only get you so far. The rest relies on intuition, experience, and data acquisition..... like how much gasoline squirts during a 5 second pulse of the cold start valve? Does the cold start valve weep when under 29 psi of pressure? Does the cold start valve get voltage and ground when the car is cold and key is in START position? have you tested the thermo time switch in the upper coolant manifold? 

 

"Got ball in sight at 2500 RPM as per the manual".... that just means that your ignition timing is perfect at that particular rpm. Who the hell knows what it's doing at idle? At 3800 rpm? In between? Get an adjustable timing light. Mark TDC on the crank pulley UP FRONT...and graph / map the advance curve every 500 rpm to 5000 rpm. If you're using a whiz-bang 1-2-3 unit... well.... try an analog one instead. 

 

 

Money is no substitute for expertise. Start with having the distributor rebuilt / properly curved at "Advanced Distributors" in MN. He's GOOD.  

 

 

HTH!

 

Paul

 

 

The only specialist I know in Atlanta is currently out for months with back surgery. 

This engine ran fine with the current dist before the rebuild. When it was on the bench and we installed the points we checked the movement of the advance weights by holding the shaft and turning the rotor. Also oiled the felt under the rotor. Don't think this is the problem but thanks for chiming in. 

[Golfcar]

On 9/18/2024 at 7:41 PM, tomphot said:

 

Yes , we may need to check his 30 year old gauge and attachments 

Yes, the gauge is old and so is the operator. New rebuilds take time for the rings to seat to achieve a complete seal for compression. This engine has only run 15 minutes. I'm sure the values will go up after a few hundred miles. Sure concern is noted.