effects of distributor a tooth off? and other frustrations

[Pablo M]

6 hours ago, John76 said:

Pablo, 

Are you sure the rotor is pointing to the #1 plug tower at TDC on the compression stroke ... not the TDC of the exhaust?

IMO the TDC mark and the 25-degree BB on the flywheel are more accurate and easier to see than the notches on the front pulley.

John

Absolutely positive. When I took it apart I went to great pains to make sure I had the marks on the crank pulley lined up as well as the marks on the cam gear lined up with the oiling tube. When I pulled the distributor the rotor was on #1
On reinstallation I again made sure the cams were in their right positions. 

 

I’ll have to take it all apart and check everything again. 

 

5 hours ago, Stevenc22 said:

Pablo, if the car is running, just rotate the distributor 5 degrees one direction and see if the motor smooths out, if not, try rotate the distributor 5 degrees to the other direction. You can get the timing close just by listening to the engine.

it’s not running very smooth at all and needs throttle to keep it stalling until warm. Once warm it still rough, much rougher than before with dead cylinder. 
 

I actually did try this, turning the dizzy in both directions to see what effect it had. The engine did change but never got to a place it ran smooth or well. I was turning the dizzy easily 3/8” or more to get an extreme effect. 
 

 

5 hours ago, jimk said:

He has a 123 dizzy and needs to re-synch it to the engine again.  The timing map is worthless if the zero of the 123 is not on the zero of the engine.

the 123 is not installed yet. I wanted to wait to avoid too many variables. I’m wondering now if I should install it now, if it would help, or wait to sort this out. 
 

 

4 hours ago, tzei said:

Check if wp bolts are tight enough.

I will, but I didn’t touch the water pump so if it wasn’t leaking before I don’t know why it would leak now. Except for the hose that attached. It appears to be coming from there so I suspect a dry rot hose, like a lot of the other hoses I replaced. 
 

3 hours ago, Mikesmalaga72 said:

Seems you have a Tii correct? Have you conducted the proper sequence procedure for your linkage prior to start up? 

 

 

Yes, a tii. The linkage was not disassembled as part of this work. It operated fine, if not without some play, prior to removing the head. Would it not work if I just put it all back as it came out? The only point that got disconnected was the attachment at the TB. But the entirety of the linkages from throttle to kfisher stayed connected together. 

[Mikesmalaga72]

I would assure baseline measurements of linkages per the provided diagram if not done already and verify all filter screens in the fuel system are verified clean prior to going to other faults to rule these variables out. Once the fuel system is dialed in move on to spark... making sure TDC @ nr 1 and stab the distributor so as to line up rotor tip on the notch on the distributor housing. An extra set of eyes could help if there are any around. Good luck you`ll get there soon...   

Edited November 12, 2023 by Mikesmalaga72

[Mark92131]

19 hours ago, Pablo M said:

When I took it apart I went to great pains to make sure I had the marks on the crank pulley lined up as well as the marks on the cam gear lined up with the oiling tube.

 

Just to clarify, the cam timing mark is on the cam, not on the cam gear.  You set the motor to TDC using the flywheel "OT" mark, align the cam as shown, then install the cam gear.  The marks on the crank pulley are not always correct or accurate.

 

Mark92131

[Pablo M]

2 hours ago, Mark92131 said:

 

Just to clarify, the cam timing mark is on the cam, not on the cam gear.  You set the motor to TDC using the flywheel "OT" mark, align the cam as shown, then install the cam gear.  The marks on the crank pulley are not always correct or accurate.

 

Mark92131

Correct, mark on the cam, not the gear. 
I followed the head removal instructions in Haynes Manual, the Factory Service Manual and in my research here. None of which mentioned using the OT marks on the flywheel. In fact, I'd not even become aware of the OT marks on flywheel until researching how to set the timing after it was all reassembled, researching timing specifically (didnt come up in in searching anything head related). 

Edited November 12, 2023 by Pablo M

[Pablo M]

22 hours ago, Mikesmalaga72 said:

I would assure baseline measurements of linkages per the provided diagram if not done already and verify all filter screens in the fuel system are verified clean prior to going to other faults to rule these variables out. Once the fuel system is dialed in move on to spark... making sure TDC @ nr 1 and stab the distributor so as to line up rotor tip on the notch on the distributor housing. An extra set of eyes could help if there are any around. Good luck you`ll get there soon...   

I'm having trouble understanding why I should start with the linkage. Basic troubleshooting I learned in HS auto shop was to start with the things you modified or changed first before starting down the overall list of what could cause this. The throttle and linkage was working fine before head removal. Engine ran, throttle worked, but ran a little rough and was way down on power. Discovered the dead cylinder and addressed that. Now, with everything reassembled it barely runs, wont idle. So I don't think the linkage is where I should start troubleshooting. Sure, linkage probably needs to be looked at and the bushings replaced, but not as part of this troubleshooting. Help me understand why my reasoning isn't correct.

So to me timing seems to be first thing to check, and I'll have to retrace my steps, reset TDC at #1 compression stroke: marks on crank pulley, marks on cam, dizzy rotor at #1, then check the cam lobes visually to be sure as well. I'm 100% certain I did all this in reassembling it but will recheck my work. 

 

I'll have to post a video of the engine running. I can start it and it runs. Starts hard, runs poorly, not smooth at all. Except fully up to temp it wont idle on its own and needs coaxing from constant throttle management. Once at temp, idles but VERY rough. 

 

The car has tons of issues, but I thought addressing the dead cylinder would at least get me a running, driving car. It was a running, driving car before, even with the dead cylinder, but just ran poorly (rough idle and no power). By no power I mean it would struggle to get to 75mph, foot on the floor. 

[Mikesmalaga72]

Methodical diagnosing procedures should be looked into. While you have done a lot of great work the air/fuel section should be examined on the Tii`s. Sure you can run it but they can be finicky if not eliminating possible variables due to what I mentioned. Kugelfischer belt timing marks are another scenario as well as fuel injector function, delivery valve, and suction valve function filter screens on Kufi pump inlet and pump screens, testing fuel volume over time etc. So in summary...    

Some of the hard starting/running could be related to the cold start valve section thermo time switch and, or warm up regulator and or linkage/throttle valve incorrectly positioned and missing/broken throttle shaft cup at the bottom of it @ the Kufi pump. Once those variables are tackled one could move to fire/spark. plug wires @ proper firing order, valves adjusted, properly gapped plugs and ignition points clearances cap condition.   

Wishing you the best  

[ray_]

(One of) the problem(s) is in the ignition circuit.

 

Or I'll eat my hat.

Edited November 13, 2023 by ray_

[Pablo M]

Drive over to garage for some tools and cold started it. Actually sounds better than first time. Still won’t hold a steady idle or high idle. Even on steady throttle it surges. 

IMG_1298.mov

 

Edited November 13, 2023 by Pablo M
spelling

[jgerock]

Please tell us more about your intake manifold.  Looks like some various parts here.

[Pablo M]

3 hours ago, jgerock said:

Please tell us more about your intake manifold.  Looks like some various parts here.

Nothing special. It’s a 72 tii and could never get the plastic tubes to seal, so I replaced the intake plenum, tubes, manifold with aluminum ones from 74 tii.  Painted tubes black just for period look. 

[cda951]

I re-read this thread---if the engine is not running well and surging, it is difficult to verify the exact ignition timing. You can confirm that basic ignition timing is correct by looking at the timing light while someone else cranks the engine with the fuel pump fuse removed to prevent the engine from starting. It should be somewhere in the zero to ~10 degrees BTDC while cranking, even +/- 5 degrees on either end of that range the engine should start and run well enough. Ignition timing being off would not cause surging as shown in the video, that is an air/fuel ratio problem.

 

You just installed a rebuilt cylinder head along with the intake manifold. I agree with the advice to re-check the basic throttle linkage/D-cam settings as outlined in the factory manual, along with re-checking that there are no vacuum leaks. Make sure all the intake runners and hoses are good and tight. Then go back and check the tii basics, and see how the engine runs with the warmup regulator "hat" fully extended. You can block off the cold start extra air throttle body bypass hoses if need be to eliminate their influence on warmup, and then see how the engine runs after it has fully warmed up.

[Pablo M]

10 hours ago, cda951 said:

You just installed a rebuilt cylinder head along with the intake manifold. I agree with the advice to re-check the basic throttle linkage/D-cam settings as outlined in the factory manual, along with re-checking that there are no vacuum leaks. 

To be clear, I only installed the head. Intake was already on from before. I had been fighting vacuum leaks in my quest to get engine running, and had identified and cured many, then to discover the dead cylinder. Could there be another vacuum leak? Sure. But I've replaced many if not all the hoses already. The replacement intake solved many of the vacuum leaks and engine ran way better after installing it. I've been looking to see if there might be more leaks but haven't identified any. I can keep looking. 

[cda951]

13 hours ago, Pablo M said:

To be clear, I only installed the head. Intake was already on from before. I had been fighting vacuum leaks in my quest to get engine running, and had identified and cured many, then to discover the dead cylinder. Could there be another vacuum leak? Sure. But I've replaced many if not all the hoses already. The replacement intake solved many of the vacuum leaks and engine ran way better after installing it. I've been looking to see if there might be more leaks but haven't identified any. I can keep looking. 

 

OK, If you are confident that most if not all of the vacuum leaks are fixed, then you need to get back to the tii basics as mentioned before. When these engines surge like that, it is a mixture issue. Set the throttle linkage/D-cam and mixture and idle adjustment screws back to the baseline as prescribed by the factory manual and tune from there.

 

Edited November 14, 2023 by cda951

[Pablo M]

1 hour ago, cda951 said:

 

OK, If you are confident that most if not all of the vacuum leaks are fixed, then you need to get back to the tii basics as mentioned before. When these engines surge like that, it is a mixture issue. Set the throttle linkage/D-cam and mixture and idle adjustment screws back to the baseline as prescribed by the factory manual and tune from there.

 

I think, first, I will go back and search for vacuum leaks as they seem to be the most likely cause. I'll run the engine and spray the various areas with carb cleaner (or whatever suitable spray I should be using-I'll research). I think I used carb cleaner before. Its within the realm of possibilities I screwed up a gasket somewhere on the intake system reinstalling it.

Then I'll go back and retrace my steps on assembly. Check linkages, etc. 

[larry_in_socal]

Hi Pablo,

I've been reading your posts, when you put in the rebuilt head, did you do a valve adjustment? did you use the old eccentric at the valve adjustment. just my too cents here. When I was getting my 93' Toyota pickup back on the road, I did some reading about the valve adjustment studs and how they can basically mushroom to look like a turtle shell, in other words they are not perfectly flat when measuring the valves. I purchased new totally flat adjustment screws and the valve adjustment was perfect.

 

Are the eccentrics in your engine the originals and are they in good shape? If they are all "chewed" up perhaps they are not allowing a proper valve adjustment. Can't speak for the BMW eccentric , but on my Toyota, the new valve adjustment screws allowed me to dial in a great valve adjustment.

Just going back to basics here.. did you do a simple compression check across all cylinders to verify that the compression was withing range across the engine. Not sure exactly what the percentages are but having compression that is off could make the engine run like crap.  If you are past all of this, that's cool.. just adding my 2 cents here..