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1971 1750 Berlina FI hard start

8K views 119 replies 10 participants last post by  max71 
#1 ·
Looking to help a friend with his Alfa. I have a lot of experience with carbs, not so much with FI.

Are there main culprits to check to cure hard starting? He says initial and all starts there after take quite a while. Rough running then warmed up - smooth. Rough at cold seems normal.

Suggestions are gratefully welcomed.
 
#3 ·
when set up right, they start easily, even in REALLY cold environment. does your friend have wes ingram's spica manual? he should, it will be the best money he spends on the car. when wrong, there is no simple magic bullet. works same as carb car - start at the beginning and work your way methodically through to the end. the worst thing, is since has been wrong for a long time, might have been subjected to any number of "short cuts" to compensate, try to find a quick fix. hard to predict what state is in now. verify everything - TDC, cam timing, ignition timing etc. then can look to the spica. simple stuff - make sure no air leaks. the manual has dimensional specs and trouble shooting guides.
 
#4 · (Edited)
Thanks so much for the reply barboncino!

I suspected as much. Here's my plan. All suggestions or critique is welcomed:

1. Check Ignition dwell (60?) and timing
2. Check Fuel pump pressure
3. Check Timing of the FI pump + checking specs. I would need to know the offset for this pump which I believe is in the PDF's he's given me. I'm interested to know how to check for the alignment marks.
4. Spark Plugs & gap if not the original style
5. Injectors checked and cleaned if necessary ( if possible)
6. I would check valve clearances but with overhead cams I'm not qualified

Will check to see if he has the Ingram manual

Appreciate your extremely knowledgeable suggestions.
 
#5 ·
valve clearances and valve timing is #1, you measure on the heel of the cam perpendicular to the tappet with a feeler gauge (stone cold). the adjusting - removing the cam(s), changing the shims & resetting the timing is the tricky part.

then set the points followed by ignition timing, then SPICA timing. Of interest would be the cold start solenoid and the micro(cut-off) switch. One test when cranking is to crack open a feedline at an injector, if no gas comes out and there is fuel going into the SPICA pump an internal problem with the SPICA pump is indicated.

the injectors are high pressure, and need to be tested in a specific manner, not a backyard job

in addition to the Wes Ingram manual there is a factory SPICA manual that is a very good reference, also the Autobooks Giulia Manual has a section on SPICA.

Replacing the main fuel filter and cleaning/replacing the pre-pump screen filter is also a good place to start.

the factory airbox is best.
 
#6 ·
I'm good at setting valves although I've never done it with overhead cams. I can measure though. I had a feeling the injectors wouldn't be shadetree possible.

"then set the points followed by ignition timing, then SPICA timing. Of interest would be the cold start solenoid and the micro(cut-off) switch. One test when cranking is to crack open a feedline at an injector, if no gas comes out and there is fuel going into the SPICA pump an internal problem with the SPICA pump is indicated."

Good suggestion!
 
#7 · (Edited)
I would also like to test the cold start solenoid (CSS). Do I need a special wrench to loosen and tighten the CSS?

NOTE:: The photo is from a post found here on the forum. It is NOT an actual photo of the car I would be working on.

This is what I found:

This adjustment controls the amount of "extra" gas that is injected while the starter motor is operating. This adjustment affects how easily your Alfa starts.
• A) With the engine at operating temperature and all other Fl adjustments completed, allow the engine to idle. Disconnect the wire to the Cold Start solenoid and connect one end of a jumper wire to the positive battery cable at the starter solenoid. Temporarily, connect the other end of the jumper wire to the Cold Start Solenoid. If the Cold Start Solenoid is adjusted correctly, the engine will continue to idle, but at a speed 100 to 200 rpm slower than before.
• B) If the engine immediately dies when the Cold Start Solenoid is jumped, the solenoid is allowing too much gas to be injected. Use a punch and hammer to loosen the lock nut at the base of the Cold Start Solenoid. Turn the solenoid counter clockwise one eighth turn and retest. Continue until the engine idle speed drops a couple hundred rpm when the solenoid is jumped. Tighten the lock nut when the adjustment is correct.
• C) If there is no change in idle speed when the solenoid is jumped, the solenoid is not allowing enough gas to be injected (or is not operating). Turn the solenoid one eighth turn clockwise to increase the fuel flow. Retest. Repeat this step until the idle speed drops approximately 150 rpm when the Cold Start Solenoid is jumped. Tighten the lock nut.
 

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#8 · (Edited)
No special wrench needed. Adjust the CSS so that there is about a quarter inch between the casting and the bottom of the CSS.

If that doesn't help, I would do a complete tuneup/readjustment of the system. It could be that the Thermostatic Actuator (T/A) is not adjusted correctly, the short and/or long rods are not adjusted correctly, or that the relay crank idle stop and wide-open throttle stop screws are not adjusted correctly.

It's probable that previous owners have fiddled with the system not having a clue what they were doing. It's possible for the system to be very far out-of-tune, and still actually run, but not optimally of course.

If you need the Spica Technical Manuals, send me a PM.

The loose wire there connects to the chassis white wire that runs along the right side of the engine compartment.
 
#9 ·
Thanks!

That photo was taken from a thread here and not an actual photo of the engine. My friend bought the car from his brother who had the engine completely rebuilt (according to him) and I do not think he tweaked it afterwards. That doesn't mean it was set up correctly - which apparantly it was not with the issue stated.

I have to learn how to adjust the TA as that is on the list to check. I have a FI Manual that was created by Alfa called "Instructions and Maintenance Manual for Alfa Romeo 1750 Fuel Injected Models USA Version" - It gives maintenance schedules and basic adjustment but I do not see anything about the Thermostatic Actuator. I'd PM but it won't allow it until I have 4 more posts.
 
#14 ·
Firstly, yea 10!

I've read some many conflicting views on spark plugs -- what is the time and tested replacement for the stock which is NLA?

One thread said NGK BP6ES which is the same for my car except others say its too deep and could hurt the top of the piston.
 
#18 ·
UPDATE

I had to go check out the car because there was confusion on the dizzy and I figured I best look so the right parts are ordered.

1. The distributor is electronic. Rob at Centerline looked at the cap which I wanted ordered with point and said that's what he thinks it is. Correct. So all I can do is check the advance is 'all in' at 5K

2. There was considerable oil around the the injector throats and #2 and #4 has some oil pooled in their throats. #1 and #3 were dry. There seems to be oil all over the rubber that connects the air box to the throat bodies. Its also on the SPICA. I wasn't sure where it was coming from. He says he almost never needs to add oil so what is spraying might have to wait until its fired.

3. After pulling and inspecting the plugs they look correct. No signs of being too lean or rich

4. The CSS is 1/4" to base. I ran a jumper from the battery to the CSS just to test and heard the clunk of it moving. Did it twice to be sure. * I was expecting this to be the issue so I'm a little thrown by it being at the correct height - at least according to you folks.

5. Checked the TA and it measures normal for temp.

6. The collector box (I don't know the name - its the black box bolted to the firewall. One hose goes to the valve cover and one to the air box ad the bottom hose I think goes to vacuum) was oily and signs of rust trails from a loose hose.

6. Aside from the hard start all the time, he claims the car plateaus at 4000 RPM and is very slow to try to reach redline. He says the car seems to have an unnatural amount of torque at low end. According to some here and a couple others - the thought is that the cams are not timed right and are retarded. I will check this out when the parts arrive. I see from other threads a person needs special wrenches and torque to 70 lbs. I have an expensive torque wrench but not those tools so I will look to verify and check the valve clearance then he’s best having a shop do that who has the special tools.

At this point I would be surprised if the cam timing is not off. As far as the hard start I guess I could keep richening the CSS until it does start normally. Of course I'll check to see where the SPICA is set on FNC control. Does that sound like a proper plan? Most ignition thoughts are gone since its electronic.
 
#19 ·
for TDC, have used the hot rod type bolt threaded in sparkplug holder doodad. worked well. the only caveat... do not use w lots of movement from TDC, i.e., get close to TDC w screwdriver sitting on piston if need be... then fine tune w the bolt. if start w crank too far away from tdc, stand a good chance of catching a valve head on the bolt. do not ask me how i know this.
what is an electronic distributor? like an RML or 123? not an Ljet type i hope. if it is, get rid of it and install a good points type distributor. will need correct coil as well to go with.
 
#20 ·
I have a dial guage but no way to have it magnetically lock. I had that bolt you mentioned but worry on this car as its not mine and with a flash light something seems odd. I'm sure its just viewing. I'll try the screw driver and I have a small ruler I use for turntables.

Apparantly according to Centerline its a stock electronic ignition. Here's a pic of the cap. My friend just ordered the part and Rob at Centerline said it was an 80's Alfa part and normal upgrade for older Alfa's. If it were my car I would do as you suggest. If its working I'll just back off.

The rest is a concern.
 

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#21 ·
how the heck does this work? is a spica engine no? are there points inside this thing? if so, not an electronic distributor... if no points - is an electronic one... the Ljet ones are tiny like this but there is nothing inside it but a rotor. if so, is entirely wrong - and no wonder it does not run right. something is wrong - probably me. in any case, more research needed here.
 
#23 ·
You have the Marelli Plex distributor. It is electronic. Alfa used them on the 80 and 81 Spica injected cars. it was also sold as an aftermarket kit.

You won't need any special tools to adjust the cam timing. The tools you probably saw are for the 1980 an later cars that have a VVT intake cam.

You also don't need any special tools to adjust the valves. It can be done with a feeler gauge. You just need valve shims to adjust the clearance.
 
#24 ·
Yes, that's what Rob called it!

I'm looking at this tool enclosed which gave me pause. No problem checking or even shimming the valves. My concern was loosening the cams, adjusting and then getting the proper torque on the nut.

Is there pics of doing this or a thread for this engine? It would make life a lot easier....
 

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#26 ·
Both of your cams will look like the exhaust cam in the video.
 
#28 ·
Yep.
 
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