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post #46 of 97 (permalink) Old 03-22-2005, 11:58 AM Thread Starter
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According to the Montreal site...

"Cylinder numbering from front to back is 1-2-3-4 right side, 5-6-7-8 left side. Montreal manuals indicate that the upper distributor arm (B circuit) feeds cylinders 2-3-5-8. This can be misleading because the firing order for this circuit is 2-3-8-5. The order of the plug leads clockwise from the front of the distributor should be 1-3-4-8-6-5-7-2, which gives the correct firing order 1-5-4-2-6-3-7-8."

This is the way my car is set up. Each cylinder has the number stamped on it and the Marelli distributor cap is also labelled so its kind hard to get it wrong.
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post #47 of 97 (permalink) Old 03-22-2005, 12:49 PM
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Ok. However, I've found that trusting the numbering on a replaceable distributor cap can lead you astray if it's not meant for that particular engine or the distributor was turned from the intended factory orientation. Whenever dealing with an engine new to me, I'll rotate the engine to #1 power stoke, confirm it by looking at the valves, line up the crankshaft pulley index, then check the position of the rotor in relation to where it should be pointing, as well as physically verify that the wires are going to the correct cylinder regardless of how the cap may be labeled.

Crossed up plug wires have miffed an awful lot of people.

It sounds as if you're going to have to remove the injection pump to fix the oil leak anyway. If it turns out to be a bad cup seal in the microswitch, I think I might have a serviceable replacement for you. BTW, they are no longer available. Also, for information, the oil level in the Logic Section will normally be less than a quarter of the apparent capacity. That's where the overflow drain holes are (going to the engine sump). Basically there's enough oil in there for the bottom part of the 3D cam assembly to run in. It then splash lubricates the rest of the Logic Section.

John Stewart
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post #48 of 97 (permalink) Old 03-25-2005, 09:57 AM Thread Starter
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Spent some time today preparing for the removal of the pump.

I can see the small gap at the bottom of each barrel but there is no movement of this when throttle is moved.

I plan to take the pump out tomorrow.

With respect to the timing marks .......I can find the timing marks on the spica pump sprocket and casing.

On the main flywheel, I have the following marks
1P
AM
(three horizontal while lines)
5P
AF

The Monti manual gives information on 1P,5P, AF and AM but I guess there should also be a 'I' mark --- maybe thats the third marking....

I guess to be safe, I will just line up the spica pump timing marks, then mark the main flywheel and ensure that the engine does not move....
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post #49 of 97 (permalink) Old 03-25-2005, 10:33 AM
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For the curious sorts,

1P = TDC for cylinder #1
5P = TDC for cylinder #5
AF = Fixed ignition timing mark (idle setting) for the "A" ignition circuit
AM - Maximum ignition advance for the "A" ignition circuit

There should also be a "PMS" mark (Punto Morto Superior or top dead center) which is used only to properly align the flywheel on the crank.

Of the three white lines, I bet that one of the lines is shorter than the others. This would be the letter "I" to indicate the injection pump timing mark.

Jim

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post #50 of 97 (permalink) Old 03-25-2005, 11:08 AM
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I don't have a Monty SPICA book, but the Spiders are timed at 70 deg BTDC of the intake stroke. I would expect the V-8 to be close to the same.
Here's a picture of the "I" (iniezione) stamp and the index stamp on a Spider crankshaft. See if your mark is similar.

It's important that the SPICA pump is timed correctly. Although the engine will run, you might get flat spots in throttle response, but it just won't be "right" unless timed correctly.
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Last edited by Roadtrip; 03-25-2005 at 11:12 AM.
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post #51 of 97 (permalink) Old 03-25-2005, 12:36 PM
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Quote:
Originally Posted by ar15625
I tried out the test of the sender by using a test lamp

Wiring diagram as follows:


Starter motor live] <-------test lamp -----> fuel pressure sender

With the ignition on, test lamp is on (lit)
Once I switch to the last point on the ingition, the fuel pump kicks in and the
test lamp goes out after about 1 second.

I think not run the engine to idle (as I did not get time today) to see if there
is any issue as the engine is run.

Given the sender looks ok, I will try to trace the wiring back to the dash to see what wrong .... but it look like I have at least 7psi...
ar15625,
I'd like to interrupt for a second. I have been following this thread and have yet to hear what the fuel pressure between the fuel pumps and the injector pumps,is? I saw an asumption you have at least 7 lbs pressure, but have you actually measured it with an inline fuel pressure gauge yet? What was the figure? Or.. If you disconnect the fuel supply line from somewhere between the tank and pumps and the FI pumps so its free and you turn on the ignition key don't try to start just turn it on will it shoot gasoline for 20 feet ?or shoot it into a see thru container and does it fill quickly. Maybe I missed something?
Ross

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post #52 of 97 (permalink) Old 03-25-2005, 12:48 PM Thread Starter
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I haven't actually tested the fuel pressure using a gauge (as I dont have an inline one ).

Since the car was running ok up to the point I was 'messing' with the injectors lines --- I am continuing with the assumption that the fuel pressure is ok. The air idles fine and reved freely to max revs in neutral--- only when in gear, the car seriously lacked power.


We have already found that the pump leaks oil, the oil filter was extremely dirty --- according to 'Alfa Bible' by Braden this can lead to rack sticking.

I will see if I can find a fuel pressure gauge and check it out.

The montreal has two electric fuel pumps (3 port) mounted at the rear of the car close to the tank. I am also going to replace the pumps with a more modern single pump from a 164 (or similiar)

Any other advice welcome !
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post #53 of 97 (permalink) Old 03-25-2005, 01:49 PM
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Since the fuel low-pressure warning light is out, there should be sufficient pressure to run the pump. As a further test, you can fit a "T" into the fuel lines and check the actual pressure. With the engine not running, you will get a steady reading. With the engine running and the microsurges that the plungers create, you'll get a wildly fluctuating reading unless you have a dampened gauge. DO NOT check the fuel pressure with a deadhead reading. The fuel pumps can create very high pressure and blow a line. The SPICA fuel system is a re-circulating one.

Regardless, the pump has to come off to find the oil leak and fix that. While it's off, we can remove some inspection plates and check the operation of the various components.

I'd hold off on replacing the existing pumps. In the 4c system, you can use the fuel supply pump from the L-jet cars, if you narrow the restrictor to maintain adequate pressure in the injection pump fuel manifold. The Monty's restrictor is in the rear rather than in the outlet port of the injection pump. I don't know if the L-jet pump is going to give you sufficient flow and pressure for an 8c motor without modifying the restrictor a bit. I'm sure there's some Monty Alfisti out there on the Monty BB that knows for sure.

John Stewart
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91 164S

Last edited by Roadtrip; 03-25-2005 at 01:53 PM.
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post #54 of 97 (permalink) Old 03-25-2005, 01:54 PM Thread Starter
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thanks. I will see if I can find a suitable T connector.

Should it be connected on the inlet fuel line after the filter but before the
spica pump ?

Last edited by ar15625; 03-25-2005 at 02:00 PM.
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post #55 of 97 (permalink) Old 03-25-2005, 02:13 PM
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Yes, after the front filter and before the injection pump. You want to measure the fuel pressure that is getting to the fuel pump. Keep in mind that without the alternator running, the battery will be powering two high draw fuel pumps, so make sure the battery is fully charged. In a 4c Alfa, you'll typically get 10 psi on battery only, and 13-15 psi or so with the alternator running (putting out slightly higher voltage than the battery). Even slight voltage changes can make a large difference in the pump performance. That's why the wiring to the fuel pumps needs to be in good condition.

John Stewart
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post #56 of 97 (permalink) Old 03-25-2005, 03:30 PM
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Quote:
Originally Posted by Roadtrip
I don't know if the L-jet pump is going to give you sufficient flow and pressure for an 8c motor without modifying the restrictor a bit. I'm sure there's some Monty Alfisti out there on the Monty BB that knows for sure.
Yes, a single L-Jet pump does work in the Monty. Have a friend who did just that a number of years ago and with no mods to the restrictor. Will try to get a pic of the installation this weekend.

Jim

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post #57 of 97 (permalink) Old 03-25-2005, 04:01 PM
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I wonder why Alfa put two supply pumps in the Monty, then. Certainly one would be able to feed the fuel demand of the V-8, so I'm thinkin' that maybe the other is there to keep the flow up for cooling two pump sections, especially ones that sit on top of the engine and get the brunt of heat, vice a 4c with the pump sitting down low on the cool side of the engine. I'd be interested to know what the fuel restrictor at the tank looks like and what the size is. When fitting an L-Jet pump to a 4c car, you have to narrow the restrictor from 3/32" to 1/16" diameter to keep the pressure up due to the lower volumetric efficiency of the L-Jet pump vs. the original.

John Stewart
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post #58 of 97 (permalink) Old 03-25-2005, 05:55 PM
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Good thoughts and questions, John, to be sure. The only other bit of info I recall is that the pump came from a Milano. I'll try to find out more.....

Jim

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post #59 of 97 (permalink) Old 03-25-2005, 09:14 PM
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if you have gage just remove the low-pressure warning light switch and put the gage there.
as a side note the by-pass in the front filter should be bypassing. I can hear mine. the by-pass is also the regulator so if the spring in side is rusted and broke it could give very low PSI. so checking with a gage seems like the right thing to do.

and fix the light . when driving with out the light you could have a pluged filter and lean out with out knowing and burn a piston. I have had the happen with just one tank of gas on a new filter. I got a tank full of crap at one of the cheap no name gas-n-go
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post #60 of 97 (permalink) Old 03-26-2005, 01:05 PM Thread Starter
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Hi John

Got some time today to start pump removal.

I have found the 'I' mark on the flywheel --- its in line with the three horizontal lines but stamped in there so its difficult to see easily....

The spica socket timing marks are lined up also.

The TA is removed, the control rod for the accerlator disconnected, the CSS wire is disconnected.

I have removed the two rear bolts and 3 nuts at each side at the front of the pump so the pump is basically ready to lift out.

Only problem now is the pump is fairly solidly attached still to the engine block so my next questions are;

a) is it ok to tap it with a rubber mallet and wooden block to free it out
b) the belt is the toothed type and looks quite difficult to remove without moving the sprocket and cam (other end of the belt)

Photos attached....
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