Alfa Romeo Forums banner
1 - 20 of 26 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter · #1 ·
Hi there gang,
I'm hoping some of you will be able to shed some light on the cam timing/ crankshaft marks/ distributor position.
I have a 1983 Spider that I have had for several years.
About five or six years ago, with about 85,000 miles, a screw that holds the shifting forks to a shifting rods came off inside the gearbox, meaning I was always stuck in second gear. Instead of just addressing the gearbox issue, I decided to take on a full engine rebuild. After removing and disassembling the engine, I took the engine head over to Rick at RML in Daytona for servicing. He did a valve job and seems to have beautifully reconditioned the engine head, replacing one of the cam sprockets. That was five or six years ago and as life got in the way, I never reassembled everything until recently. The car and engine parts have been stored in a garage since that time.
I'm sorry for this level of detail, but I just want folks to know what's going on so I can get a good troubleshoot and diagnosis.

Upon rebuilding, I very carefully followed the reassembly procedures in the overhaul manual sold by IAP (I believe this is just a reproduction of the factory overhaul manual). The step where I was especially concerned was at the point that the front cover gets installed onto the block. I was very careful, in fact resetting it several times to be sure I had the distributor aligned properly. As best I can tell, I was to set the engine at TDC and then install the front cover so that the distributor rotor pointed to the index mark indicating the position of the number one spark. I believe I did this properly.

After proceeding with everything else, I am able to get the engine cranked, HOWEVER, I am seemingly having a serious issue with a lack of power.
I have replaced 3 of 4 fuel injectors that I thought were suspect, but at this point, I am beginning to think they were fine. As I hit the accelerator, the engine almost wants to die unless I push it with a feather light touch and wait for it to catch up with my foot. Even so, at take off, I really notice the car barely wants to roll unless I really rev the engine and then let go of the clutch. As the car gets moving, the engine does seem to develop power, but still at a very slow rate and still without a finely tuned sound that I recall when I pulled this decently-running engine apart. The car is certainly NOT running properly.

I have checked stuff and rechecked stuff, pulled things and replaced them. What I keep coming back to is that this sounds like a timing/misfiring issue.
Now, to give further explanation, when the car is first cranked, I use an inductive timing light on plug wire #1 and the pointer appears to sit at the "F" mark for a few moments and then (maybe after it's warmed up?) the "F" appears to roll counter clockwise and hide under the water pump.

By the way, for whatever reason, the car is idling at roughly 2,000 RPMs. I haven't addressed that yet.

I am attaching some pictures. In them, you will see that I've set the crankshaft pulley at the "F" mark. At the same position, you'll see the exhaust and intake cam timing marks are NOT at the index points. And also at the same time, note the position of the distributor to the index mark for cylinder #1 spark. Please note (take my word for it at this point) that if I set the crankshaft pulley to the "P" mark, the intake and exhaust cam timings are almost spot on and the distributor rotor is still generally pointing toward cylinder #1 spark, although obviously not in the identical position as when the pulley is on the "F" mark because it naturally rotates with the crankshaft.
As another note, This is NOT an adjustable distributor.
Please guys, help me. I'm nearly numb from re-doing different steps on this engine. Did I screw up something?
 

Attachments

·
Registered
Joined
·
4,322 Posts
I'm not familiar with the Bosch Spiders but the cams should align when you're at the 'P' mark and the distributor is nothing more than a rotor and cap so I'd say you're okay with that stuff.
 

·
Registered
Joined
·
96 Posts
This may sound off the wall, but do you have the vacuum port at the back of the head blocked off or going to the brake booster? I'd block it off with a cap to rule out a vacuum leak there.
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #4 ·
This may sound off the wall, but do you have the vacuum port at the back of the head blocked off or going to the brake booster? I'd block it off with a cap to rule out a vacuum leak there.
I did replace the brake booster hose, but I have also tried blocking the ports using my fingers to see if it improved but to no avail. As an added note, as I'm cranking the engine over, I can hear a repeated momentary sound of an air leak, but I have not found any disconnected ports. Also, I did replace the idle control o-ring but can't seem to tighten that valve down enough.
I'll try capping ports. More ideas guys?
-Bryan
 

·
Premium Member
Joined
·
3,868 Posts
Never mind.

I was wrong.

Good luck,

Vin
 

·
Administrator
Joined
·
18,170 Posts
Did you install the flywheel in the correct position? There are 6 ways it can be bolted to the crankshaft - 5 wrong & 1 right.

You really do not need a timing light to set the ignition timing. With the crank pointer at 'P' and the #1 cam lobes facing away from each other (i.e. #1 at TDC on compression the rotor should be aligned with the mark on the distributor. (your photo shows it very close - likely good enough). Further igntion timing/advance is computer controlled (assuming the flywheel is correctly installed...).

Is the wire harness connected to the AFM (Air Flow Meter)? Does the flap in the AFM move smoothly through is range?
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #7 ·
Did you install the flywheel in the correct position? There are 6 ways it can be bolted to the crankshaft - 5 wrong & 1 right.

You really do not need a timing light to set the ignition timing. With the crank pointer at 'P' and the #1 cam lobes facing away from each other (i.e. #1 at TDC on compression the rotor should be aligned with the mark on the distributor. (your photo shows it very close - likely good enough). Further igntion timing/advance is computer controlled (assuming the flywheel is correctly installed...).

Is the wire harness connected to the AFM (Air Flow Meter)? Does the flap in the AFM move smoothly through is range?
Eric,
I heeded your warnings, in addition to that of others in prior postings when I installed the flywheel, knowing what a mistake it would be to do it incorrectly. I was very particular to follow the steps and locate the proper index mark and make sure it was at the 12 o'clock position when the crank was at whatever position called for, I believe TDC or when rotor pointed to plug 1? But I certainly followed the book on this and I didn't have any trouble finding the index mark on the flywheel.
 

·
Super Moderator
Joined
·
12,255 Posts
if I set the crankshaft pulley to the "P" mark, the intake and exhaust cam timings are almost spot on and the distributor rotor is still generally pointing toward cylinder #1 spark,

Did I screw up something?
I know very little about Bosch injected Alfas. But from reading this thread, my guess is that the major stuff (cam timing, distributor timing, flywheel indexing) is OK, and the problem is something minor (loose vacuum hose, hung-up AFM, etc).

If the flywheel were 60 degrees off, I doubt the engine would run at all. Similarly, if the distributor was 180 off. The fact that the engine starts and runs, albeitly badly, suggests that the internal parts were installed OK.
 

·
Registered
Joined
·
9,966 Posts
My first thought is the VVT solenoid is stuck on.
Then I see you have an 83, so maybe do not have the solenoid operated VVT. (it came in somewhere around 83/84 I believe)

But looking at that disc on your inlet cam sprocket in the photo, you probably have the centrifugal VVT, right?

What if this is somehow stuck on?
You did mention your mechanic changed "one" of the camshaft sprockets....which one and why?

I don't know the faults of the centrifugal VVT enough to comment, but somebody here will know how to test correct operation.

If you do have the solenoid VVT then check that the little pusher rod is not stuck on (you can see thru the inspection hole)

Just an idea:)
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #10 ·
Jay, I am going to check those hoses again and replace anything that doesn't look right. I'll also check the AFM and other stuff around the intake plenum.

spiderserie4, I do indeed have the centrifugal VVT. I don't know or recall if that was originally on this engine or not. I have the old cam that Rick at RML took off of my engine head. The old one looks like the exhaust side because it doesn't have any VVT on it, but I suppose he would have just moved the VVT over to the replacement cam shaft so I wouldn't necessarily have any way of knowing.

Also, if the VVT were stuck open, would I see the "F" mark roll counter clockwise or do they not have anything to do with one another since (maybe?) the VVT is operated independently of the firing of the cylinders?

Keep firing away, guys. Thanks. When I can get to the car, hopefully tonight, I'll be checking over all of this stuff.

-Bryan
 

·
Super Moderator
Joined
·
12,255 Posts
You did mention your mechanic changed "one" of the camshaft sprockets....which one and why?
Hmm, I like spiderserie4's reasoning. It might be worth asking Rick/RML why he changed one sprocket (they usually last forever). Was he eliminating the VVT?
 

·
Trained (ex)Professional, , 1953-2018 RIP
Joined
·
16,232 Posts
Curious to know if the upper flywheel sensor is connected to the black harness connector and the lower sensor to the gray connector.
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #13 ·
Jay, he wasn't eliminating the VVT, because the VVT is still on the head. But Rick changed the entire camshaft, if I wasn't clear about that, I'm sorry. I have the old shaft that appears to have more wear on the lobes than either of the two shafts currently installed. Can a centrifugal VVT be stuck open? how can I check this? I do have the 55mm spanner wrench from totallyalfa

papajam, I was waiting for you to chime in since I've read dozens of your posts also. As to the wiring, I already made that mistake. And it's been corrected, several weeks ago and I inspected both sensors and neither of them had so much as a scrape. The car does crank and run, just not very well.

-Bryan
 

·
Premium Member
Joined
·
2,039 Posts
Spark plug wiring order correct? If not, it will run poorly, but it wouldn't explain the 2000 rpm idle.
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #15 ·
Rich,
Spark plug wiring order is definitely correct.
-Bryan
 

·
Administrator
Joined
·
18,170 Posts
Can a centrifugal VVT be stuck open? how can I check this?
Yes, they can stick 'open'. The centrifugal VVT is operated by oil pressure. Centrifugal force moves a small weight against spring pressure to open a port that allows oil pressure to affect the move (advancing the camshaft).

If you remove the intake cam cap and have a source of air pressure ~ 50-60 psi you can manually move the weight (#15 in the exploded diagram) and, with air pressure applied to the small hole in the cam bearing area (#9 in the exploded diagram), see the cam move.
 

Attachments

·
Registered
Joined
·
18 Posts
Discussion Starter · #17 ·
Eric,
Excellent information. Where did that sheet come from? I'm also attaching more pictures. In these, notice that I've set the crankshaft at "P" and see the timing marks on the cam shafts, first the exhaust and then the intake. Also note the location of the rotor relative to the cylinder #1 index point. Additionally, I'm attaching a photo of my VVT.
-Bryan
 

Attachments

·
Registered
Joined
·
9,966 Posts
Now with the P mark lined up, the cams look dead on, rotor looks dead on too.

I like that info sheet on the centrifugal VVT from Eric..........that is what I would start to investigate now.......you never know and at least you eradicate one more possible.

Apparently the early centrifugal VVT is a very good system.........of course it has to work:)
 

·
Registered
Joined
·
18 Posts
Discussion Starter · #19 ·
spiderserie4,
I agree with you re: eliminating the possibility. In some small way, I kind of hope it's the problem so I can just get on with it all. I'm beginning to wonder what the thread life is on some of these screws, off and on and off and on. :)
-Bryan
 

·
Richard Jemison
Joined
·
8,308 Posts
issues

This isn`t a cam timing / vvt issue. Motor would run adequately with VVT disabled.
Easy way to confirm is to put a exhaust cam & vernier sprocket on the intake side and set LC to 102 (not the 114 mark on the cam cap)

I would suggest trobleshooting the Bosch system. If you replace the pointer type distributor with a points/advance type distributor, and remove the large white wire from the coil (tape it up) the distributor will control the FI pulse timing and ignition timing rather than the computer.
If that corrects the problem, buy a good electronic distributor to keep on the engine. If that is beyond your mechanical accumen let Ric do it.
 
1 - 20 of 26 Posts
Top